JP7052577B2 - Optical equipment, video display equipment, and optometry equipment - Google Patents

Description

The present invention relates to an optical device, an image display device, and an optometry device.

In recent years, technologies and products related to virtual reality (VR) and augmented reality (AR) have been attracting attention. In particular, AR technology is expected to be applied to the industrial field as a means for displaying digital information as an added value in a real space, and a glass-type image display device that can be used in an action (work) environment has been developed.

In the glass type image display device, the transmission type (see-through) is the mainstream in order to visually recognize the real space and the digital image at the same time. An image display device that displays a virtual image image in front of the eye via a partial reflection film or an image guide structure, and a retinal drawing type image display device that draws an image directly on the retina via a partial reflection film or the like are beginning to appear on the market. ..

In the retina drawing type image display device, a device is disclosed in which an image generated by a laser beam is once converged in the pupil and then projected onto the retina by using Maxwell vision (see, for example, Patent Document 1). Since the light passing near the center of the pupil reaches the retina regardless of the accommodation of the crystalline lens, a focus-free state can be obtained regardless of the wearer's eyesight, and digital information becomes clear no matter where the focus is in the real space. It becomes possible to visually recognize.

In an optical device such as a retinal drawing type image display device using a laser beam, the image can be visually recognized only when the convergence position of the image ray for drawing the image is positioned in the pupil.

However, in the apparatus of Patent Document 1, since the convergence position of a light beam such as a laser beam cannot be adjusted, the user may not be able to visually recognize the image at a suitable position different for each user.

The present invention has been made in view of the above points, and an object of the present invention is to make it possible to adjust the convergence position of an image ray and the projection direction of an image.

The optical device according to one aspect of the disclosed technique includes a scanning unit that scans light in a first direction, an optical unit that guides the light scanned by the scanning unit to a surface to be projected, and the optical unit with respect to the optical unit. The scanning unit comprises a stance variable section that changes at least one of the positions or orientations of the scanning section, the scanning section has a rotating mirror that scans the light in the first direction, and the stance variable section is described. It has a rotation mechanism for rotating the scanning portion in a first direction and a translation mechanism for translating the scanning portion, and the rotation mechanism is centered on a rotation axis of the rotation mirror. The scanning unit is rotated, and the translation mechanism is arranged on the side opposite to the scanning unit with respect to the rotating mechanism, and translates the scanning unit along the incident direction of the light incident on the scanning unit. It is characterized by that.

According to the embodiment of the present invention, the convergence position of the image light beam and the projection direction of the image can be adjusted.

It is a figure explaining an example of the structure of the image display device which concerns on 1st Embodiment. It is a figure explaining an example of the structure of the scanning mirror which concerns on 1st Embodiment. It is a figure explaining an example of the hardware composition of the control part which concerns on 1st Embodiment. It is a figure which shows an example of the component of the control part which concerns on 1st Embodiment by a functional block. It is a figure explaining an example of the operation of the posture variable part which concerns on 1st Embodiment. It is a figure explaining an example of the action of rotation of the posture variable part which concerns on 1st Embodiment. It is a figure explaining an example of the action of translation and rotation of the posture variable part which concerns on 1st Embodiment. It is a figure explaining an example of the structure of the image display device which concerns on 2nd Embodiment. It is a figure explaining an example of the structure of the scanning mirror which concerns on 2nd Embodiment. It is a figure explaining an example of the operation of the scanning mirror which concerns on 2nd Embodiment. It is a figure explaining an example of the structure of the image display device which concerns on 3rd Embodiment. It is a figure explaining an example of the hardware composition of the control part which concerns on 3rd Embodiment. It is a figure which shows an example of the component of the control part which concerns on 3rd Embodiment by a functional block.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In each drawing, the same components may be designated by the same reference numerals and duplicate explanations may be omitted.

In the embodiment, a video display device including an optical device will be described as an example. The image display device of the embodiment will be described by taking as an example a retinal drawing type head-mounted display (HMD), which is a wearable terminal and draws an image directly on the user's retina using Maxwell vision.

In the embodiment, the image display device for the left eyeball of the “human” will be described as an example, but the same applies to the right eyeball. It is also possible to provide two video display devices and apply them to the eyeballs of both eyes.

In embodiments, images are synonymous with still images and video is synonymous with moving images. Further, a laser beam and a laser beam are synonymous. The laser beam is an example of the "light" described in the claims.

[First Embodiment]
FIG. 1 is a diagram showing an example of the configuration of the video display device of the present embodiment.

As shown in FIG. 1, the image display device 100 includes a laser light source 1, a lens 2, an aperture member 3, a dimming element 4, a first scanning mirror 5, a second scanning mirror 6, and the like. It has a projection mirror 7. Further, the image display device 100 includes a posture variable unit 8, an eyeglass frame 9, a control unit 20, and an operation unit 21. The eyeglass frame 9 includes a vine 9a and a holding portion 9b.

The video display device 100 is an example of the "video display device" described in the claims. Further, the configuration including the first scanning mirror 5, the second scanning mirror 6, the projection mirror 7, and the posture variable portion 8 is an example of the “optical device” described in the claims.

The lens 2, the opening member 3, the dimming element 4, the first scanning mirror 5, the second scanning mirror 6, and the posture variable portion 8 are arranged inside the vine 9a. The projection mirror 7 is arranged on the holding portion 9b. The laser light source 1 and the dimming element 4 may be arranged inside the vine 9a as shown in FIG. 1, or they may be provided outside so that only the laser beam emitted by the laser light source 1 is inside the vine 9a. It may be used as a light source. Further, the control unit 20 and the operation unit 21 may be arranged inside the vine 9a, or they may be provided outside and only the drive signal may be supplied to the inside of the vine 9a.

The divergent light emitted from the laser light source 1 is parallelized by the lens 2. The parallel light passes through the aperture member 3 and the dimming element 4 and is incident on the first scanning mirror 5. The light incident on the first scanning mirror 5 is reflected by the first scanning mirror 5, reflected by the second scanning mirror 6 and the projection mirror 7, respectively, and incident on the inside of the eyeball 50. The light rays incident on the inside of the eyeball 50 once converge in the vicinity of the pupil 52, and then are imaged on the retina 53 at the back of the eyeball 50. The laser light source 1 is an example of the "light source" described in the claims, and the lens 2 is an example of the "optical system" described in the claims.

The laser light source 1 is, for example, a semiconductor laser that emits a laser beam having a single wavelength or a plurality of wavelengths. The laser light source 1 time-modulates and emits a laser beam according to a drive signal from the control unit 20. A monochrome image is drawn by a single wavelength laser beam, and a color image is drawn by a plurality of wavelength laser beams. The image display device 100 may include a laser light source that emits a laser beam having a plurality of wavelengths in order to draw a color image, or may include a plurality of laser light sources having different wavelengths from each other. The laser beam emitted by the laser light source 1 is an example of an image beam for drawing an image.

The opening member 3 includes an opening. The opening member 3 shields a part of the laser beam incident on the opening and passes the rest thereof to shape the laser beam into a desired cross-sectional shape or diameter. The diameter of the aperture of the aperture member 3 is equal to or less than the diameter at the light intensity of 1 / e2 of the laser beam parallelized by the lens ² . Note that "e" is the base of the natural logarithm.

The opening member 3 passes through the opening member 3 and makes the diameter of the laser beam incident on the first scanning mirror smaller than the effective diameter of the first scanning mirror. In the present embodiment, a circular opening is assumed as an example of the opening, but the opening may have a partially distorted shape or an elliptical shape. With the opening member 3, the laser beam can be brought into a desired state, such as by making the cross-sectional light intensity distribution uniform, and the quality of the image beam and the image can be improved.

The dimming element 4 reduces the light intensity of the passing laser beam so as to have an appropriate light intensity in consideration of the safety of the "human" eye. The dimming element 4 is, for example, an ND (Neutral Density) filter in which an optical thin film having a predetermined transmittance is formed on a plate-shaped member made of a resin.

Appropriate light intensity considering the safety of "human" eyes is lower than class 1 defined by, for example, IEC (International Electro-technical Commission) 6025-1, which is an international standard for laser light safety. Light intensity. By setting the laser beam to a desired light intensity by the dimming element 4, a safe laser beam can be projected onto the retina, and the safety of the "human" eye can be ensured.

Although the present embodiment shows an example in which the dimming element 4 is arranged between the opening member 3 and the first scanning mirror 5, the dimming element 4 may be arranged between the opening member 3 and the lens 2. However, it may be arranged in a plurality of places. By optimizing the arrangement of the dimming element 4, it is possible to reduce the size of the image display device 100 and the like.

The first scanning mirror 5 reflects the laser beam that has passed through the dimming element 4, changes the reflection angle, and scans the laser beam in the X direction (horizontal direction) in the figure. The second scanning mirror 6 scans the laser beam scanned in the X direction by the first scanning mirror 5 in the Y direction (vertical direction) in the figure. An image or a moving image is drawn by synchronizing the laser beams and scanning in the X and Y directions. Although not shown, the image display device 100 may be provided with a known synchronization detection optical system or the like in order to synchronize the scanning of the laser beam in the X and Y directions.

The X direction is the main scanning direction in which pixels are drawn continuously in time to form a series of pixel groups. The Y direction is a sub-scanning direction in which a series of pixel groups are arranged. The main scanning direction and the sub-scanning direction intersect. The scanning speed of the first scanning mirror 5 in the main scanning direction is set higher than the scanning speed of the second scanning mirror 6 in the sub-scanning direction.

The X direction is an example of the "first direction" described in the claims, and the Y direction is an example of the "second direction" described in the claims.

The first scanning mirror 5 and the second scanning mirror 6 are, for example, 1-axis MEMS (Micro Electro Mechanical System) mirrors, respectively. The first scanning mirror 5 and the second scanning mirror 6 scan the laser beam by rotating their movable portions around a predetermined axis. The details of the configurations of the first scanning mirror 5 and the second scanning mirror 6 will be described separately with reference to FIG.

The first scanning mirror 5 and the second scanning mirror 6 are not limited to the MEMS mirror, and may be any movable object having a reflecting portion for scanning light, such as a polygon mirror and a galvano mirror. According to the MEMS mirror, it is advantageous in terms of miniaturization and weight reduction. The drive method of the MEMS mirror may be any of electrostatic type, piezoelectric type, electromagnetic type and the like.

The first scanning mirror 5 is an example of the "scanning unit" described in the claims, an example of the "first scanning mirror", and an example of the "rotating mirror".

The posture variable portion 8 translates the first scanning mirror 5 to change the position of the first scanning mirror 5. A translation mechanism is used for translation. The translation mechanism uses the rotation of the connected motor as a drive source to translate the first scanning mirror 5 according to the drive signal from the operation unit 21.

Further, the posture variable portion 8 rotates the first scanning mirror 5 to change the direction of the first scanning mirror 5. A rotation mechanism is used for rotation. The rotation mechanism uses the rotation of the connected motor as a drive source to rotate the first scanning mirror 5 according to the drive signal from the operation unit 21.

The drive source of the posture variable portion 8 is not limited to the motor, and may be, for example, a piezo actuator or the like. By using a piezo actuator, it is possible to reduce the size of the drive source compared to a motor. Further, the drive is not limited to the above-mentioned electric drive, and may be manually driven. Although the example in which the posture variable portion 8 translates and rotates the first scanning mirror 5 is shown, the configuration may be such that only the rotation is performed. By making only the rotation configuration, it is possible to simplify the configuration of the image display device 100 while ensuring the function of changing the projection direction of the image.

The operation of the posture variable portion 8 and the details of the operation will be described separately with reference to FIGS. 3 to 5.

By the way, the laser beam is reflected by the first scanning mirror 5 and then reflected by the second scanning mirror 6. If the translational amount and / or the rotation amount of the first scanning mirror 5 by the attitude variable portion 8 is large, the laser beam reflected by the first scanning mirror 5 may not be incident on the reflecting surface of the second scanning mirror 6. .. Therefore, in the present embodiment, the area of the reflecting surface of the second scanning mirror 6 is made larger than the area of the reflecting surface of the first scanning mirror 5. By doing so, even if the translational amount and / or the rotation amount of the first scanning mirror 5 is increased, the laser beam reflected by the first scanning mirror 5 is incident on the reflecting surface of the second scanning mirror 6. The range of translation and / or rotation of the first scanning mirror 5 can be expanded.

Returning to FIG. 1, the projection mirror 7 is a mirror having a concave reflecting surface. The projection mirror 7 reflects the laser beam scanned by the first scanning mirror 5 and the second scanning mirror 6, converges once in the vicinity of the pupil, and then forms an image on the retina. The image or video drawn by the scanned laser beam is directly projected onto the retina of the user who wears the image display device 100 via the projection mirror 7. Light passing near the center of the pupil reaches the retina regardless of the focal adjustment of the crystalline lens. Therefore, the user can clearly see the projected image or the video in the focused state regardless of the position of the eye in the real space. Such a state is a so-called focus-free state. The user's eye is an example of the "projected surface".

The projection mirror 7 is formed by depositing a metal reflective film such as aluminum on a concave surface processed from, for example, resin or glass as a base material to form a mirror surface. However, a base material such as resin or glass may be mirror-processed without providing the metal reflective film. The shape of the concave surface may be spherical or aspherical. When an aspherical surface is used, the optical aberration of the image formed by the concave mirror can be corrected with higher quality.

Further, the mirror formed on the concave surface may be a half mirror. The half mirror reflects light of some light intensities of the incident light and transmits light of the remaining light intensities. By using a half mirror, it is possible to realize a see-through type video display device that can simultaneously view real space and digital video.

For example, when the image display device 100 is a see-through type, in FIG. 1, among the light propagating from the outside of the image display device 100 in the negative Z direction toward the eyeball 50, the light transmitted through the projection mirror 7 is actually used. The space is visible. On the other hand, the digital image is visually recognized by the laser beam emitted from the laser light source 1 and reflected by the projection mirror 7. The intensity of the reflected light and the intensity of the transmitted light by the half mirror do not necessarily have to be one-to-one. The projection mirror 7 is an example of an “optical unit”.

The control unit 20 inputs video data that is the source of the video to be drawn, and controls the emission of the laser light by the laser light source 1 based on the input video data. Further, the control unit 20 controls the scanning of light by the first scanning mirror and the second scanning mirror by controlling the driving of the first scanning mirror and the second scanning mirror. The details of the hardware configuration of the control unit 20 will be described separately with reference to FIG. The details of the functional configuration of the control unit 20 will be described separately with reference to FIG.

The operation unit 21 supplies drive signals for driving the translation mechanism 8c and the rotation mechanism 8b included in the posture variable unit 8. The operation unit 21 is, for example, an interface such as a dial or a push button provided on the vine 9a. The user can instruct the translation mechanism 8c of the translation direction and the translation amount, or instruct the rotation mechanism 8b of the rotation direction and the rotation amount via the operation unit 21. The operation unit 21 may be composed of a mechanism unit such as a micrometer head, and the translation mechanism 8c may be translated or the rotation mechanism 8b may be rotated by manually operating the mechanism unit. The translation by the translation mechanism includes translation.

In the example of FIG. 1, a configuration having an opening member 3 and a dimming element 4 is shown, but if the safety of the intensity of the light projected on the user's retina is ensured, the dimming element 4 and the like are shown. It is not always necessary to provide.

By the way, the image display device 100 can change the current or voltage applied to the laser light source 1 to change the light intensity of the emitted laser beam. As a result, the brightness of the image or the video can be adjusted according to the brightness of the surrounding environment in which the video display device 100 is used. For example, when the light intensity of the laser beam emitted by the laser light source 1 is maximized, the dimming element 4 passes the laser beam so as to have an appropriate light intensity in consideration of the safety of the "human" eye. Reduces the light intensity of.

Next, FIG. 2 is a diagram illustrating an example of the configuration of the first scanning mirror 5. In FIG. 2, the directions indicated by the arrows are the α direction, the β direction, and the γ direction, respectively. The first scanning mirror 5 includes a support substrate 41, a movable portion 42, a meandering beam portion 43, and a meandering beam portion 44.

The meandering beam portion 43 has a plurality of folded portions and is formed in a meandering manner, one end of which is connected to the support substrate 41 and the other end of which is connected to the movable portion 42. The meandering beam portion 43 includes a beam portion 43a including three beams and a beam portion 43b including three beams. The beams of the beam portion 43a and the beams of the beam portion 43b are alternately formed every other beam. Each of the beams included in the beam portion 43a and the beam portion 43b is independently provided with a piezoelectric member.

Similarly, the meandering beam portion 44 has a plurality of folded portions and is formed in a meandering manner, one end of which is connected to the support substrate 41 and the other end of which is connected to the movable portion 42. The meandering beam portion 44 includes a beam portion 44a including three beams and a beam portion 44b including three beams. The beams of the beam portion 44a and the beams of the beam portion 44b are alternately formed every other beam. Each of the beams included in the beam portion 44a and the beam portion 44b is independently provided with a piezoelectric member.

The number of beams in the beam portions 43a and 43b is not limited to three and may be arbitrary.

The piezoelectric members included in the beam portions 43a, 43b, 44a, and 44b are not shown in FIG. 2, but are provided as a piezoelectric layer in a part of each beam layer formed of, for example, a multilayer structure. In the following, the piezoelectric members included in the beam portions 43a and 44a may be collectively referred to as the piezoelectric member 45a, and the piezoelectric members included in the beam portions 43b and 44b may be collectively referred to as the piezoelectric member 45b.

When a voltage having opposite phases is applied to the piezoelectric member 45a and the piezoelectric member 45b to cause the meandering beam portion 44 to warp, the adjacent beam portions bend in different directions. This deflection is accumulated, and a rotational force for reciprocating the reflection mirror 42a is generated around the A axis in FIG.

The movable portion 42 is formed so as to be sandwiched between the meandering beam portion 43 and the meandering beam portion 44 in the β direction. The movable portion 42 is provided with a reflection mirror 42a in the central portion, and the reflection mirror 42a is rotated around the A axis by the rotational power of the meandering beam portion 43 and the meandering beam portion 44. Due to this rotation, the laser beam incident on the reflection mirror 42a and reflected is scanned in the α direction.

The support substrate 41 is formed so as to surround the movable portion 42, the meandering beam portion 43, and the meandering beam portion 44. The support substrate 41 is connected to and supports the meandering beam portion 43 and the meandering beam portion 44. Further, the support substrate 41 indirectly supports the meandering beam portion 43 and the movable portion 42 connected to the meandering beam portion 44.

The MEMS mirror constituting the first scanning mirror 5 is formed by microfabrication of silicon or glass using, for example, micromachining technology. By the micromachining technology, a highly accurate and minute movable mirror can be integrally formed on a substrate with a driving part such as a meandering beam part.

Specifically, for example, one SOI (Silicon On Insulator) substrate is molded by an etching process or the like. Reflective mirrors 42a, meandering beam portions 43 to 44, piezoelectric members 45a to 45b, electrode connecting portions and the like are integrally formed on the molded substrate to form a MEMS mirror. The reflection mirror 42a and the like may be formed after the SOI substrate is molded, or may be formed during the SOI substrate molding.

The SOI substrate is a substrate in which a silicon oxide layer is provided on a silicon support layer made of single crystal silicon (Si), and a silicon active layer made of single crystal silicon is further provided on the silicon oxide layer. Since the silicon active layer is thin in the γ direction with respect to the α direction or the β direction, the member composed of only the silicon active layer has a function as an elastic portion having elasticity.

The SOI substrate does not necessarily have to be flat and may have a curvature or the like. Further, the member used for forming the MEMS mirror is not limited to the SOI substrate as long as the substrate can be integrally molded by etching treatment or the like and can be partially elastic.

The configuration of the second scanning mirror 6 is the same as that of the first scanning mirror 5. However, while the first scanning mirror 5 is installed in the image display device 100 so as to scan the laser beam incident on the reflection mirror 42a in the main scanning direction, the second scanning mirror 6 sub-scans the laser beam. It is installed in the image display device 100 so as to scan in the direction.

In the case of scanning in the main scanning direction, a voltage of a sinusoidal waveform is applied to the piezoelectric members 45a and 45b provided in the first scanning mirror 5 in opposite phase as a drive signal from the control unit 20. The frequency of the voltage of the sinusoidal waveform is a frequency corresponding to the resonance mode of the movable portion 42 around the A axis. By applying a voltage having a sinusoidal waveform, the first scanning mirror 5 reciprocates at a low voltage and at a very large rotation angle.

On the other hand, in the case of scanning in the sub-scanning direction, the voltage of the sawtooth wave waveform is applied to the piezoelectric members 45a and 45b provided in the second scanning mirror 6 in opposite phase as the drive signal from the control unit 20. As a result, the second scanning mirror 6 reciprocates at a desired drive frequency.

The sawtooth wave waveform can be generated by superimposing a sine wave waveform. Further, in the present embodiment, an example in which the second scanning mirror 6 is driven by the voltage of the sawtooth wave waveform when scanning in the sub-scanning direction is shown, but the present invention is not limited to this. For example, a waveform in which the apex of the sawtooth wave waveform is rounded, a waveform in which a linear region of the sawtooth wave waveform is a curve, or the like may be used. Further, it may have a unique waveform shape according to the device characteristics of the second scanning mirror 6.

FIG. 3 is a block diagram showing an example of the hardware configuration of the control unit 20 of the present embodiment. The control unit 20 includes a CPU (Central Processing Unit) 22, a ROM (Read Only Memory) 23, a RAM (Random Access Memory) 24, a light source drive circuit 25, and a scanning mirror drive circuit 26. These are electrically connected to each other via the system bus 27.

The CPU 22 comprehensively controls the operation of the control unit 20. The CPU 22 controls the operation of the entire control unit 20 by executing a program stored in the ROM 23 using the RAM 24 as a work area (work area), and realizes various functions described later.

The light source drive circuit 25 is an electric circuit that is electrically connected to the laser light source 1 and applies a current or a voltage to the laser light source 1 to drive the laser light source 1. The laser light source 1 turns on or off the emission of the laser beam by the drive signal output by the light source drive circuit 25, and changes the light intensity of the emitted laser beam.

The scanning mirror drive circuit 26 is, for example, an electric circuit. The scanning mirror drive circuit 26 is electrically connected to the first scanning mirror 5 and applies a voltage to the first scanning mirror 5 to drive the first scanning mirror 5. The first scanning mirror 5 changes the rotation angle of the reflection mirror 42a included in the movable portion 42 by the drive signal output from the scanning mirror drive circuit 26.

Further, the scanning mirror drive circuit 26 is electrically connected to the second scanning mirror 6 and applies a voltage to the second scanning mirror 6 to drive the second scanning mirror 6. The second scanning mirror 6 changes the rotation angle of the reflection mirror according to the drive signal output by the scanning mirror drive circuit 26.

The control unit 20 can realize the functional configuration described below by the hardware configuration shown in FIG.

FIG. 4 is a diagram showing an example of a component of the control unit 20 of the present embodiment as a functional block. It should be noted that each functional block of the control unit 20 shown in FIG. 4 is conceptual and does not necessarily have to be physically configured as shown in the figure. All or part of each functional block can be functionally or physically dispersed / combined in any unit. Each processing function performed in each function block of the control unit 20 may be realized by a program executed by the CPU 22 described above, or may be realized as hardware by wired logic.

The control unit 20 includes an emission control unit 31, a light source drive unit 32, a scan control unit 33, and a scan mirror drive unit 34.

The emission control unit 31 inputs video data that is the source of the video to be drawn, and outputs a control signal for driving and controlling the laser light source 1 to the light source driving unit 32 based on the input video data.

The scanning control unit 33 inputs video data that is the source of the video to be drawn, and based on the input video data, scan mirrors control signals for driving and controlling the first scanning mirror 5 and the second scanning mirror 6. Output to the drive unit 34.

The emission control unit 31 and the scanning control unit 33 are realized by, for example, a CPU 22 or the like.

When the image visually recognized at a suitable position has distortion or the like, the emission control unit 31 and the scanning control unit 33 may perform control so as to correct the distortion or the like.

The light source driving unit 32 drives the laser light source 1 by applying a current or a voltage to the laser light source 1 based on the control signal input from the emission control unit 31. The light source driving unit 32 is realized by, for example, a light source driving circuit 25 or the like.

The scanning mirror driving unit 34 drives the first scanning mirror 5 by applying a voltage to the first scanning mirror 5 based on the control signal input from the scanning control unit 33. Further, the scanning mirror driving unit 34 drives the second scanning mirror 6 by applying a voltage to the second scanning mirror 6 based on the control signal input from the scanning control unit 33. The scanning mirror driving unit 34 is realized by, for example, a scanning mirror driving circuit 26 or the like.

Next, FIG. 5 is a diagram for explaining in detail an example of the operation of the posture variable portion 8 of the present embodiment. The posture variable portion 8 has a base member 8a, a rotation mechanism 8b, and a translation mechanism 8c.

The base member 8a is a plate-shaped member made of metal or the like. In FIG. 5, the first scanning mirror 5 is fixed to the surface of the base member 8a on the positive Y direction side. This "fixing" may be fixed by an adhesive, or may be fixed by fitting or screwing. This point is the same in the following. A rotation mechanism 8b is arranged on the negative Y direction side of the base member 8a, and the base member 8a is fixed to the rotation mechanism 8b.

FIG. 5 shows a state before the first scanning mirror 5 is rotated and translated by the rotation mechanism 8b and the translation mechanism 8c, and a state after the rotation and translation.

In FIG. 5, the movable portion 52b shown by the solid line shows the state before rotation and translation, and the movable portion 52c shown by the alternate long and short dash line shows the state after rotation and translation. .. Further, the laser beam 83 shown by the solid line indicates the central scanning ray of the laser beam by the first scanning mirror 5 before rotation and translation. The central scanning ray is a laser beam located at the center in the scanning range of the laser beam.

On the other hand, the laser beam 84 shown by the alternate long and short dash line indicates the central scanning ray of the laser beam by the first scanning mirror 5 after being rotated and translated.

The laser beam 84 is tilted with respect to the laser beam 83 by a rotation angle θ. Further, the laser beam 84 is shifted with respect to the laser beam 83 by a translation amount S in a direction parallel to the incident direction of the laser beam.

The rotation mechanism 8b integrally rotates the base member 8a and the first scanning mirror 5 in the direction of the arrow 81. The rotation axis of this rotation coincides with, for example, the rotation axis of the movable portion 42 of the first scanning mirror 5 (axis A in FIG. 2). It should be noted that this "match" does not require a perfect match, but allows an error to the extent that it is recognized as an error in assembly or processing. This point is the same in the following. Further, in the following, the “rotating shaft of the movable portion 42 of the first scanning mirror 5” may be referred to as the “rotating shaft of the first scanning mirror 5”.

Further, it is desirable that the rotation axis of the first scanning mirror 5 is included in the incident position of the laser beam in the first scanning mirror 5. The cross-sectional area of the incident laser beam is smaller than the area of the reflecting surface of the first scanning mirror 5.

A translation mechanism 8c is arranged on the negative Y direction side of the rotation mechanism 8b, and the rotation mechanism 8b is fixed to the translation mechanism 8c. The translation mechanism 8c integrates the rotation mechanism 8b, the base member 8a, and the first scanning mirror 5 and translates them in the direction of the arrow 82. The translational direction is a direction along the incident direction of the laser beam emitted from the laser light source 1 and incident on the first scanning mirror 5. Such a direction is, for example, a direction parallel to the incident direction of the laser beam incident on the first scanning mirror 5. It should be noted that this "parallel" does not require perfect parallelism, but allows an error to the extent that it is recognized as an error in assembly or processing.

Even when the rotation mechanism 8b, the base member 8a, and the first scanning mirror 5 are translated by the translation mechanism 8c, the rotation axis of the rotation by the rotation mechanism 8b coincides with the rotation axis of the first scanning mirror 5. Translate in the same state.

An example of the operation of the posture variable portion 8 of the present embodiment will be described with reference to FIGS. 6 to 7. First, FIG. 6 is a diagram illustrating an example of the action of rotation of the posture variable portion 8 of the present embodiment. FIG. 6A is a diagram illustrating a change in the laser beam trajectory due to the rotation of the posture variable portion 8. In FIG. 6A, the laser beam is incident on the first scanning mirror 5 and reflected. The reflected laser beam is reflected by the second scanning mirror 6 and the projection mirror 7 and is incident on the eyeball 50.

In FIG. 6A, the laser beam shown by the solid line shows the state before rotation. The laser beam 61 indicates a central scanning ray. The laser beam 62 indicates a scanning ray corresponding to the maximum scanning angle in the positive X direction. The laser beam 63 indicates a scanning ray corresponding to the maximum scanning angle in the negative X direction. The laser beams 61 to 63 converge near the center of the pupil 52, pass through the pupil 52, and form an image on the retina.

On the other hand, in FIG. 6A, the laser beam shown by the broken line shows the state after rotation. For example, this is a case where the first scanning mirror 5 is rotated by the posture variable portion 8 so that the angle of incidence of the laser beam on the first scanning mirror 5 becomes large. The laser beam 64 indicates a central scanning ray. The laser beam 65 indicates a scanning ray corresponding to the maximum scanning angle in the positive X direction. The laser beam 66 indicates a scanning ray corresponding to the maximum scanning angle in the negative X direction.

The convergence position of the laser beams 64 to 66 is near the center of the pupil 52, and all of these laser beams pass through the pupil 52 and form an image on the retina. As described with reference to FIG. 5, the rotation mechanism 8b of the posture variable portion 8 rotates on the rotation axis of the first scanning mirror 5, and the rotation axis of the first scanning mirror 5 is the first scanning mirror 5. It is included in the incident position of the laser beam incident on. As a result, the reflection position of the laser beam on the first scanning mirror 5 does not change before and after the rotation of the posture variable portion 8, and the convergence position of the laser beam by the projection mirror 7 does not change. Therefore, the focus-free state is secured. On the other hand, the position of reflection of the scanned laser beam on the projection mirror 7 is shifted in the positive X direction, and the user can visually recognize the image shifted in the positive X direction.

Further, although not shown in FIG. 6A, when the first scanning mirror 5 is rotated by the posture variable portion 8 so that the angle of incidence of the laser beam on the first scanning mirror 5 becomes smaller. The position of reflection of the scanned laser beam on the projection mirror 7 is shifted in the negative X direction, and the user can visually recognize the image shifted in the negative X direction. Even in this case, due to the above action, the convergence position of the laser beam does not change before and after the rotation of the posture variable portion 8, and the focus-free state is ensured.

By rotating the first scanning mirror 5 by the posture variable portion 8 in this way, it is possible to change the viewing direction of the image by the user while ensuring the focus-free state without changing the convergence position of the laser beam. can. For example, when the user wears the image display device 100, by operating the posture variable unit 8 while visually recognizing the image, the user can adjust the viewing direction of the image according to the user's suitable position for viewing the image. can.

On the other hand, FIG. 6B is a diagram illustrating a change in the laser beam trajectory due to the movement of the eyeball. Similar to FIG. 6A, the laser beam shown by the solid line indicates the state before rotation, and the laser beam shown by the broken line indicates the state after rotation. For example, this is a case where the first scanning mirror 5 is rotated by the posture variable portion 8 so that the angle of incidence of the laser beam on the first scanning mirror 5 becomes large.

In FIG. 6B, the laser beam enters the eyeball 50, converges once in the pupil 52, passes through the pupil 52, and forms an image in the retina 53. The figure shown on the left side of FIG. 6B is a case where the eyeball 50 is facing the front. The figure shown in the center is the case where the eyeball 50 is oriented in the positive X direction (right direction in the figure), and the figure shown on the right side is the case where the eyeball 50 is further oriented in the positive X direction. ..

As shown in the central figure of FIG. 6B, when the eyeball 50 faces the positive X direction, the center of the pupil 52 shifts in the positive X direction. Then, as shown in the figure on the right side of FIG. 6B, when the eyeball 50 faces the positive X direction, the center position of the pupil 52 shifts further in the positive X direction, and as a result, the laser beam is emitted. At the convergent position, the pupil 52 is vignetted and does not reach the retina 53.

If only the posture variable portion 8 is rotated in this way, the user may not be able to visually recognize the image depending on the amount of movement of the eyeball 50.

Next, FIG. 7 is a diagram illustrating an example of the translational and rotational actions of the posture variable portion 8 of the present embodiment. FIG. 7A is a diagram illustrating changes in the laser beam trajectory due to translation and rotation of the posture variable portion 8. Similar to FIG. 6A, in FIG. 7A, a laser beam is incident on and reflected by the first scanning mirror 5. The reflected laser beam is reflected by the second scanning mirror 6 and the projection mirror 7 and is incident on the eyeball 50.

In FIG. 7A, the laser beam shown by the solid line shows the state before translation and rotation. Similar to FIG. 6A, the laser beam 61 indicates a central scanning ray. The laser beam 62 indicates a scanning ray corresponding to the maximum scanning angle in the positive X direction. The laser beam 63 indicates a scanning ray corresponding to the maximum scanning angle in the negative X direction. The laser beams 61 to 63 converge near the center of the pupil 52, pass through the pupil 52, and form an image on the retina.

On the other hand, in FIG. 7A, the laser beam shown by the broken line shows the state after translation and rotation. For example, the attitude variable portion 8 rotates the first scanning mirror 5 so that the angle of incidence of the laser beam on the first scanning mirror 5 is large, and the first scanning mirror 5 is lasered on the first scanning mirror 5. This is the case when the light beam is advanced in the incident direction. The laser beam 67 indicates a central scanning ray. The laser beam 68 indicates a scanning ray corresponding to the maximum scanning angle in the positive X direction. The laser beam 69 indicates a scanning ray corresponding to the maximum scanning angle in the negative X direction. The convergence positions of the laser beams 67 to 69 are deviated from the vicinity of the center of the pupil 52 in the positive X direction (to the right in the figure).

Further, although not shown in FIG. 7A, the posture variable portion 8 rotates the first scanning mirror 5 so that the incident angle of the laser beam on the first scanning mirror 5 becomes large, and the first scanning mirror 5 is rotated. When the 1-scan mirror 5 is retracted in the incident direction of the laser beam to the 1-scan mirror 5, the convergence position of the laser beams 67 to 69 is in the negative X direction from the vicinity of the center of the pupil 52 (left direction in the figure). It shifts.

On the other hand, FIG. 7B is a diagram illustrating a change in the laser beam trajectory due to the movement of the eyeball. Similar to FIG. 7A, the laser beam shown by the solid line shows the state before translation and rotation. The laser beam shown by the broken line indicates the state after translation and rotation. For example, the first scanning mirror 5 is rotated by the attitude variable portion 8 so that the incident angle of the laser beam on the first scanning mirror 5 becomes large, and the first scanning mirror 5 is rotated by the attitude variable portion 8. This is a case where the laser beam incident on the scanning mirror 5 is advanced in the incident direction.

In FIG. 7B, a laser beam is incident on the eyeball 50, converges once in the pupil 52, passes through the pupil 52, and is imaged in the retina 53. The figure shown on the left side of FIG. 7B is a case where the eyeball 50 is facing the front. The figure shown in the center is the case where the eyeball 50 is oriented in the positive X direction (right direction in the figure), and the figure shown on the right side is the case where the eyeball 50 is further oriented in the positive X direction. ..

As shown in the center of FIG. 7B and the figure on the right side, when the eyeball 50 faces the positive X direction, the center of the pupil 52 shifts in the positive X direction. However, unlike the case of FIG. 6, the convergence position of the laser beams 67 to 69 is shifted in the positive X direction due to the advancement of the first scanning mirror 5 by the attitude variable portion 8. Therefore, the laser beams 67 to 69 reach the retina 53 without vignetting in the pupil 52.

In this way, by rotating the first scanning mirror in the posture variable portion 8, it is possible to change the viewing direction of the image by the user while ensuring the focus-free state. Further, by translating the first scanning mirror by the posture variable portion 8, the convergence position of the laser beams 67 to 69 can be shifted. As a result, even if the eyeball 50 moves, vignetting or the like in the pupil 52 of the laser beams 67 to 69 can be prevented.

As described above, the image display device 100 of the present embodiment changes the positions or orientations of the scanning portions such as the first scanning mirror 5 and the second scanning mirror 6 that scan the laser beam and the scanning portions. It includes a posture variable portion 8 and a projection mirror 7 that projects a scanned laser beam onto the user's retina. By translating and / or rotating the first scanning mirror 5 by the posture variable unit 8, it is possible to provide an image display device capable of adjusting the convergence position of an image ray and the projection direction of an image at an arbitrary timing. can.

Since the distance between the pupils (distance between the eyeballs) and the like are different for each user, the position where the image is visually recognized differs for each user when the image display device 100 is attached, and the image may be visually recognized at an unsuitable position. .. In addition, since the suitable position for visual recognition differs for each user, the image may be visually recognized at an unsuitable position.

According to the present embodiment, by operating the posture variable unit 8 while visually recognizing the image, the user can adjust the projection direction of the image according to the position suitable for viewing the image of the user. This allows the user to visually recognize the image at a suitable position. Further, by operating the posture variable unit 8 while visually recognizing the image, it is possible to adjust the convergence position of the image light beam and avoid a state in which the image cannot be visually recognized due to vignetting of the laser beam in the pupil 52. Further, since the adjustment is performed using the mechanical portion, the adjusted state does not change due to vibration or the like, and the suitable state is stably maintained.

Further, according to the present embodiment, since the image is drawn directly on the user's retina using Maxwell vision, the image can be clearly visually recognized regardless of the position in the real space.

These effects are the same in the optical device including the first scanning mirror 5, the second scanning mirror 6, the projection mirror 7, and the posture variable portion 8.

In the present embodiment, the glass-type HMD has been described as an example of the image display device, but the image display device such as the HMD is not only directly attached to the head of a "human" but also has a member such as a fixed portion. It may be indirectly attached to the head of a "human" through the device.

[Second Embodiment]
Next, the video display device of the second embodiment will be described with reference to FIGS. 8 to 10. In the second embodiment, the description of the same components as those of the above-described embodiment may be omitted.

In this embodiment, a fixed mirror and a biaxial scanning mirror are used as a scanning unit for scanning a laser beam. The biaxial scanning mirror scans the laser beam in the biaxial direction.

FIG. 8 is a diagram showing an example of the configuration of the video display device 100a of the present embodiment. The image display device 100a includes a fixed mirror 10, a two-axis scanning mirror 11, and a posture variable portion 8A.

The fixed mirror 10 is a mirror that reflects a laser beam that has passed through the dimming element 4 toward the biaxial scanning mirror 11. The fixed mirror 10 is fixed to the vine 9a of the eyeglass frame 9. The surface of the fixed mirror 10 is not limited to a flat surface, and may have an arbitrary shape such as a concave surface or a convex surface.

The 2-axis scanning mirror 11 reflects the laser beam reflected by the fixed mirror 10 toward the projection mirror 7 and changes the reflection angle to direct the laser beam in the X direction (horizontal direction) and the Y direction (vertical direction). ) Is scanned in the biaxial direction. An image or a moving image is drawn by synchronizing the laser beams and scanning in the X and Y directions. Although not shown, the image display device 100a may be provided with a known synchronization detection optical system or the like in order to synchronize the scanning of the laser beam in the X and Y directions.

The 2-axis scanning mirror 11 is, for example, a 2-axis MEMS mirror. Details of the configuration of the 2-axis scanning mirror 11 will be described separately with reference to FIG.

The 2-axis scanning mirror 11 is not limited to the MEMS mirror, and may be configured by combining a polygon mirror, a galvano mirror, or the like having a reflecting portion for scanning light. According to the MEMS mirror, it is advantageous in terms of miniaturization and weight reduction. The drive method of the MEMS mirror may be any of electrostatic type, piezoelectric type, electromagnetic type and the like.

The 2-axis scanning mirror 11 is an example of the "scanning unit" described in the claims, and is an example of a "rotating mirror".

The posture variable portion 8A rotates the biaxial scanning mirror 11 to change the direction of the biaxial scanning mirror 11. The posture variable portion 8A rotates the biaxial scanning mirror 11, for example, about the axis of rotation of the biaxial scanning mirror 11 in the horizontal direction (X direction). It is desirable that the axis of rotation of the biaxial scanning mirror 11 in the horizontal direction (X direction) is at the incident position of the laser beam incident on the biaxial scanning mirror 11. A rotation mechanism is used for rotation. The rotation mechanism uses the rotation of the connected motor as a drive source to rotate the two-axis scanning mirror 11 according to the drive signal from the operation unit 21.

Further, the posture variable portion 8A translates the biaxial scanning mirror 11 to change the position of the biaxial scanning mirror 11. The posture variable portion 8A translates the biaxial scanning mirror 11 in a direction along the direction of incidence of the laser beam on the biaxial scanning mirror 11, for example. The direction along the incident direction of the laser beam on the biaxial scanning mirror 11 is, for example, a direction parallel to the incident direction of the laser beam on the biaxial scanning mirror 11. A translation mechanism is used for translation. The translation mechanism uses the rotation of the connected motor as a drive source to translate the two-axis scanning mirror 11 according to the drive signal from the operation unit 21.

The configuration of the posture variable portion 8A is the same as that of the posture variable portion 8. The details of the action of the posture variable portion 8A will be described separately with reference to FIG.

The image or video is drawn by a laser beam scanned by the biaxial scanning mirror 11 and directly projected onto the retina of the user who wears the image display device 100a. Since the laser beam passing near the center of the pupil reaches the retina regardless of the accommodation of the crystalline lens, the user can focus the projected image or video regardless of the position of the eye in the real space. It can be clearly seen in the state of being in the state.

Next, FIG. 9 is a diagram illustrating an example of the configuration of the two-axis scanning mirror 11. In FIG. 9, the directions indicated by the arrows are the α direction, the β direction, and the γ direction, respectively. The biaxial scanning mirror 11 includes a support substrate 91, a movable portion 92, a meandering beam portion 93, a meandering beam portion 94, and an electrode connecting portion 95.

The meandering beam portion 93 has a plurality of folded portions and is formed in a meandering manner, one end of which is connected to the support substrate 91 and the other end of which is connected to the movable portion 92. The meandering beam portion 93 includes a beam portion 93a including three beams and a beam portion 93b including three beams. The beams of the beam portion 93a and the beams of the beam portion 93b are alternately formed every other beam. Each of the beams included in the beam portion 93a and the beam portion 93b is independently provided with a piezoelectric member.

Similarly, the meandering beam portion 94 has a plurality of folded portions and is formed in a meandering manner, one end of which is connected to the support substrate 91 and the other end of which is connected to the movable portion 92. The meandering beam portion 94 includes a beam portion 94a including three beams and a beam portion 94b including three beams. The beams of the beam portion 94a and the beams of the beam portion 94b are alternately formed every other beam. Each of the beams included in the beam portion 94a and the beam portion 94b is independently provided with a piezoelectric member.

The number of beams in the beam portions 93a and 93b is not limited to three and may be arbitrary.

The piezoelectric members included in the beam portions 93a, 93b, 94a, and 94b are not shown in FIG. 9, but are provided as a piezoelectric layer in a part of each beam layer formed of, for example, a multilayer structure. In the following, the piezoelectric members included in the beam portions 93a and 94a may be collectively referred to as the piezoelectric member 95a, and the piezoelectric members included in the beam portions 93b and 94b may be collectively referred to as the piezoelectric member 95b.

When a voltage signal having opposite phases is applied to the piezoelectric member 95a and the piezoelectric member 95b to cause the meandering beam portion 94 to warp, the adjacent beam portions bend in different directions. This deflection is accumulated, and a rotational force for reciprocating the reflection mirror 92a is generated around the A axis in FIG.

The movable portion 92 is formed so as to be sandwiched between the meandering beam portion 93 and the meandering beam portion 94 in the β direction. The movable portion 92 includes a reflection mirror 92a, a torsion bar 92b, a piezoelectric member 92c, and a support portion 92d.

The reflection mirror 92a is formed by, for example, depositing a metal thin film containing aluminum, gold, silver, etc. on a base material. One end of the torsion bar 92b is connected to the reflection mirror 92a and extends in the positive and negative α directions to rotatably support the reflection mirror 92a.

One end of the piezoelectric member 92c is connected to the torsion bar 92b, and the other end is connected to the support portion 92d. When a voltage is applied to the piezoelectric member 92c, the piezoelectric member 92c bends and deforms, causing the torsion bar 92b to twist. The twist of the torsion bar 92b becomes the rotational power, and the reflection mirror 92a rotates around the B axis.

Due to the rotation of the reflection mirror 92a around the A axis, the laser beam incident on the reflection mirror 92a is scanned in the α direction. Due to the rotation of the reflection mirror 92a around the B axis, the laser beam incident on the reflection mirror 92a is scanned in the β direction.

The support portion 92d is formed so as to surround the reflection mirror 92a, the torsion bar 92b, and the piezoelectric member 92c. The support portion 92d is connected to the piezoelectric member 92c to support the piezoelectric member 92c. Further, the support portion 92d indirectly supports the torsion bar 92b connected to the piezoelectric member 92c and the reflection mirror 92a.

The support substrate 91 is formed so as to surround the movable portion 92, the meandering beam portion 93, and the meandering beam portion 94. The support substrate 91 is connected to and supports the meandering beam portion 93 and the meandering beam portion 94. Further, the support substrate 91 indirectly supports the meandering beam portion 93 and the movable portion 92 connected to the meandering beam portion 94.

The manufacturing method of the 2-axis scanning mirror 11 is the same as the manufacturing method of the first scanning mirror 5 described in the first embodiment. The driving method is the same as the driving method of the first scanning mirror 5 and the second scanning mirror 6 of the first embodiment.

Next, FIG. 10 is a diagram illustrating an example of the translational and rotational actions of the posture variable portion 8A of the present embodiment. FIG. 10 shows the change of the laser beam trajectory due to the translation and rotation of the attitude variable portion 8A. In FIG. 10, the laser beam is incident on the fixed mirror 10 and reflected toward the biaxial scanning mirror 11. The reflected laser beam is reflected by the biaxial scanning mirror 11 and the projection mirror 7 and is incident on the eyeball 50.

The laser beam shown by the solid line in FIG. 10 shows the state before translation and rotation. The laser beam 71 indicates a central scanning ray. The laser beam 72 indicates a scanning ray having a maximum angle in the positive X direction. The laser beam 73 indicates a scanning ray having a maximum angle in the negative X direction. The laser beams 71 to 73 converge near the center of the pupil 52, pass through the pupil 52, and form an image on the retina.

On the other hand, the laser beam shown by the broken line in FIG. 10 shows the state after translation and rotation. For example, the posture variable portion 8A rotates the biaxial scanning mirror 11 so that the angle of incidence of the laser beam on the biaxial scanning mirror 11 becomes small, and the biaxial scanning mirror 11 is moved to the biaxial scanning mirror 11. This is a case where the laser beam is retracted (away from the fixed mirror 10) in the incident direction. The laser beam 74 indicates a central scanning ray. The laser beam 75 indicates a scanning ray having a maximum angle in the positive X direction. The laser beam 76 indicates a scanning ray indicating the maximum angle in the negative X direction. The convergence positions of the laser beams 74 to 76 are deviated from the vicinity of the center of the pupil 52 in the negative X direction.

On the contrary, although not shown in FIG. 10, the posture variable portion 8A rotates the two-axis scanning mirror 11 so that the angle of incidence of the laser beam on the two-axis scanning mirror 11 is small, and the two-axis scanning mirror 11 is rotated. When the biaxial scanning mirror 11 is advanced (closer to the fixed mirror 10) in the direction of incidence of the laser beam on the scanning mirror 11, the convergence position of the laser beams 74 to 76 is in the positive X direction from the vicinity of the center of the pupil 52. It shifts.

If the translational movement amount and the rotation angle by the posture variable portion 8A are further increased, the incident direction of the laser beam to the eyeball 50, that is, the projection direction of the image is greatly changed along with the deviation of the convergence position of the laser beam.

Further, when the biaxial scanning mirror 11 is rotated by the posture variable portion 8A so that the incident angle of the laser beam becomes small, the convergence position of the laser beam does not change and the projection direction of the image is negative. It changes in the X direction.

As described above, according to the present embodiment, the convergence position of the image light beam and the projection direction of the image can be changed by translating and / or rotating the two-axis scanning mirror 11 in the posture variable portion 8A. Further, according to the present embodiment, the optical device including the fixed mirror 10, the two-axis scanning mirror 11, the projection mirror 7, and the posture variable portion 8A can be miniaturized. Further, the image display device provided with the optical device can be miniaturized.

According to the present embodiment, by disposing the biaxial scanning mirror 11 in the optical path between the fixed mirror 10 and the eyeball 50, the optical device and the image display device provided with the optical device are further miniaturized. be able to.

The other effects are the same as those described in the first embodiment.

[Third Embodiment]
Next, the video display device of the third embodiment will be described with reference to FIGS. 11 to 12. In the third embodiment, the description of the same components as those of the above-described embodiment may be omitted.

The image display device of the present embodiment has a configuration for detecting the pupil position, and the posture variable portion translates and / or rotates the first scanning mirror according to the change in the pupil position with the movement of the eyeball. As a result, the convergence position of the image light beam and the projection direction of the image are automatically adjusted by following the movement of the eyeball.

FIG. 11 is a diagram showing an example of the configuration of the video display device 100b of the present embodiment. The image display device 100b includes a detection laser light source 12, an optical position detection element 13, and a control unit 20b.

The detection laser light source 12 irradiates the laser beam toward the pupil 52 of the eyeball 50. The detection laser light source 12 emits a laser beam having directivity. The detection laser light source 12 is, for example, a semiconductor laser.

The wavelength of the light emitted from the detection laser light source 12 is preferably the wavelength of near-infrared light, which is invisible light, so as not to obstruct the visual recognition of the "human" whose pupil position is detected. However, the present invention is not limited to this, and visible light may be used.

The light position detecting element 13 receives the laser beam emitted from the detection laser light source 12 and reflected by the eyeball 50, and detects the position of the laser beam.

The surface of the cornea is a transparent body containing water and generally has a reflectance of about 2 to 4%. The laser beam incident on the vicinity of the pupil 52 is reflected by the reflection point P on the corneal surface of the eyeball 50 and is incident on the light position detecting element 13. The optical position detecting element 13 detects the incident position of the laser beam on the optical position detecting element 13.

The optical position detection element 13 is, for example, a two-dimensional PSD (Position Sensitive Detector). The two-dimensional PSD detects the current value according to the distance to the electrode in two directions orthogonal to each other from the position of the incident light on the light receiving surface, and the position of the incident light from the ratio of the current values in the two directions. Is calculated and output. The two-dimensional PSD can detect the position of the incident light independently of the light intensity of the incident light. Therefore, even if there is a difference in the amount of reflected light due to the reflected position in the eyeball 50 or the like, highly sensitive position detection is possible without being affected by the difference in the amount of reflected light.

However, the optical position detecting element 13 is not limited to the two-dimensional PSD. One-dimensional PSDs that can detect the position of the incident light in the X direction are arranged in the Y direction, and one-dimensional PSDs that can detect the position of the incident light in the Y direction are arranged in the X direction to XY of the incident light. The position in the plane may be detected. In this case, since the one-dimensional PSD is cheaper than the two-dimensional PSD or the like, the effect that the cost of the optical position detecting element 13 can be suppressed can be obtained.

Further, an image pickup device such as a CCD or CMOS may be used as the light position detection element 13, and the position of the light may be detected or estimated by image processing based on the spatial intensity distribution of the light incident on the image pickup surface.

An array light source such as a VCSEL (Vertical Cavity Surface Emitting LASER) or an LDA (Laser Diode Array) may be used as the detection laser light source 12. When an array light source is used, the light emitting portion is switched according to the movement of the eyeball 50, and the angle of incidence of the laser beam on the eyeball 50 is changed, so that the laser beam reflected by the eyeball 50 is the light receiving surface of the light position detection element 13. It is possible to prevent or reduce the deviation from the above.

A configuration having a detection laser light source 12 and an optical position detecting element 13 and detecting a pupil position is an example of the “detection unit” described in the claims.

The detection signal by the optical position detection element 13 is input to the control unit 20b. The translation and / or rotation of the first scanning mirror 5 is controlled by the attitude variable unit 8 based on the input detection signal.

FIG. 12 is a block diagram showing an example of the hardware configuration of the control unit 20b of the present embodiment. The control unit 20b has a stage drive circuit 28. The stage drive circuit 28 is an electric circuit that is electrically connected to the motor included in the attitude variable portion 8 and drives the motor by applying a voltage. The motor is provided in each of the translation mechanism 8c and the rotation mechanism 8b provided in the posture variable portion 8. The translation mechanism 8c translates with the motor as the drive source, and the rotation mechanism 8b rotates with the motor as the drive source.

FIG. 13 is a diagram showing an example of a component of the control unit 20b of the present embodiment as a functional block. The control unit 20b includes a pupil position estimation unit 35, an attitude control unit 36, and a stage drive unit 37.

The pupil position estimation unit 35 estimates the center position of the pupil 52 based on the received detection signal of the optical position detection element 13. The detection signal by the optical position detection element 13 corresponds to the direction of the normal vector of the reflection point P in the eyeball 50, that is, the three-dimensional shape. The pupil center position is estimated based on the correspondence between the three-dimensional shape and the eyeball model.

More specifically, the pupil position estimation unit 35 substitutes the input detection signal (position data) into an inverse calculation formula for estimating the rotation angle of the eyeball 50, and calculates the eyeball rotation angle. The pupil position estimation unit 35 calculates the pupil center position using the model of the eyeball surface shape based on the calculated eyeball rotation angle.

The pupil position estimation unit 35 is realized by, for example, the CPU 22.

The attitude control unit 36 outputs a control signal for translating and rotating the attitude variable unit 8 to the stage drive unit 37 based on the pupil center position estimated by the pupil position estimation unit 35. As a result, the convergence position of the image light beam or the projection direction of the image is automatically adjusted according to the movement of the eyeball 50.

More specifically, for example, the relationship between the convergence position of the image beam for visually recognizing the image at a suitable position, the projection direction of the image, the center position of the pupil, the translational amount of the posture variable portion 8, and the rotation amount is determined. It is obtained in advance by experiments, simulations, etc., and is stored in a memory such as ROM 23 or RAM 24. The posture control unit 36 acquires the translational amount and the rotation amount of the posture variable unit 8 for visually recognizing the image at a suitable position by referring to the memory based on the estimated pupil center position. The attitude control unit 36 outputs a control signal indicating the acquired translation amount and rotation amount to the stage drive unit 37.

The attitude control unit 36 is realized by, for example, the CPU 22.

The stage drive unit 37 applies a voltage to the motor included in the attitude variable unit 8 based on the control signal input from the attitude control unit 36 to drive the translation mechanism 8c and the rotation mechanism 8b. The stage drive unit 37 is realized by, for example, a stage drive circuit 28 or the like.

If the image at a suitable position has distortion or the like, the emission control unit 31 and the scanning control unit 33 may perform control so as to correct the distortion or the like.

As described above, according to the present embodiment, by controlling the posture variable portion according to the change in the pupil position due to the movement of the eyeball, vignetting or the like in the pupil of the image projected on the retina is suppressed. , It becomes possible to form an image on the retina that follows the change in the pupil position. The user can always see a good image without being influenced by the movement of the eyeball.

In the present embodiment, as an example of the "detection unit for detecting the position of the eyeball", a configuration for detecting the position of the pupil is shown, but the present invention is not limited to this. The "detector that detects the position of the eyeball" includes the position of the pupil of the eyeball (the position of the cornea near the pupil), the tilted position of the eyeball, the rotation position of the eyeball, the rotation angle of the eyeball (rotation angle), the tilted position of the line of sight, etc. May be detected.

The other effects are the same as those described in the first and second embodiments.

[Fourth Embodiment]
Next, the optometry device of the fourth embodiment will be described. In the fourth embodiment, the description of the same components as those of the above-described embodiment may be omitted.

For example, the optical device and the image display device of the present invention can also be adopted as an optometry device. The optometry device refers to a device capable of performing various tests such as a visual acuity test, an optical power test, an intraocular pressure test, and an axial length test. The optometry device is a device that can perform an examination without contacting the eyeball, and controls a support portion that supports the subject's face, an optometry window, and a display unit that projects examination information onto the subject's eyeball during the optometry. It has a unit and a measurement unit. The subject fixes his face on the support and stares at the examination information projected by the display from the optometry window. At this time, since the eyeball position and the easy-to-see projection direction are different for each subject, the optical device of the present embodiment can be used as the display unit. Further, by using the image display device of the present embodiment, it is possible to realize a glass-type optometry device. As a result, the space required for the examination and a large optometry device are not required, and the examination can be performed with a simple configuration regardless of the location.

Further, when it is required to look at one point without moving the eyeball (line of sight) in order to improve the measurement accuracy of the measuring unit, a video display device provided with the pupil position detecting means of the present embodiment can be used, and the pupil position detection can be used. By feeding back the pupil position (line of sight) information obtained by the means to the control unit, it is possible to perform measurement according to the pupil position information of the eyeball.

Although the optical device, the image display device, and the optometry device according to the embodiment have been described above, the present invention is not limited to the above embodiment, and various modifications and improvements can be made within the scope of the present invention. ..

1 Laser light source 2 Lens (an example of optical system)
3 Aperture member 4 Dimming element 5 First scanning mirror (example of scanning unit, example of first scanning mirror, example of rotating mirror)
6 Second scanning mirror 7 Projection mirror 8, 8A Posture variable part 8a Base member 8b Rotating mechanism 8c Translation mechanism 9 Glasses frame 9a Crane 9b Holding part 10 Fixed mirror 11 2-axis scanning mirror (an example of scanning part, rotating mirror One case)
12 Laser light source for detection 13 Optical position detection element 20, 20b Control unit 21 Operation unit 22 CPU
23 ROM
24 RAM
25 Light source drive circuit 26 Scanning mirror drive circuit 27 System bus 28 Stage drive circuit 31 Emission control unit 32 Light source drive unit 33 Scan control unit 34 Scanning mirror drive unit 35 Pupil position estimation unit 36 Attitude control unit 37 Stage drive unit 41, 91 Support Substrate 42, 92 Movable part 43, 93 Serpentine beam part 44, 94 Serpentine beam part 50 Eyeball 52 Pupil 53 Retina 100, 100a, 100b Image display device P Reflection point

Japanese Patent No. 6209456

Claims (11)

A scanning unit that scans light in the first direction,
An optical unit that guides the light scanned by the scanning unit to the projected surface, and
A posture variable portion that changes at least one of the positions or orientations of the scanning portion with respect to the optical portion, and
Equipped with
The scanning unit has a rotating mirror that scans the light in the first direction.
The posture variable portion includes a rotation mechanism that rotates the scanning portion in the first direction, and a rotation mechanism.
It has a translation mechanism that translates the scanning unit, and has a translation mechanism.
The rotation mechanism rotates the scanning portion around the rotation axis of the rotation mirror.
The translation mechanism is an optical device that is arranged on the side opposite to the scanning unit with respect to the rotation mechanism and translates the scanning unit along the incident direction of the light incident on the scanning unit. .. The scanning unit is
The first scanning mirror that scans in the first direction and
A second scanning mirror that scans in a second direction different from the first direction is provided.
The optical device according to claim 1 , wherein the posture variable portion changes at least one of the position and the direction of the first scanning mirror. The light reflected by the first scanning mirror is incident on the second scanning mirror.
The optical device according to claim 2 , wherein the area of the reflecting surface of the second scanning mirror is larger than the area of the reflecting surface of the first scanning mirror. The scanning unit is
With a fixed mirror,
A two-axis scanning mirror that rotates in two different axial directions,
The optical device according to any one of claims 1 to 3 , wherein the posture variable portion changes the position or orientation of the two-axis scanning mirror. The optical device according to claim 4 , wherein the two-axis scanning mirror is arranged between the fixed mirror and the projected surface. Light source and
The optical device according to any one of claims 1 to 5 , which scans the light emitted from the light source to form an image.
An image display device comprising: a control unit for controlling the emission of the light by the light source and scanning of the light by the optical device. The image display device according to claim 6 , further comprising an optical system for parallelizing the light emitted from the light source. The image display device according to claim 7 , further comprising an opening member provided in an optical path between the optical system and the optical device and restricting the passage of the light. The image display device according to any one of claims 6 to 8 , further comprising a dimming element provided in an optical path between the light source and the optical device and reducing the light intensity of the light. The image display device is a device that displays an image on a human eyeball.
It is equipped with a detection unit that detects the position of the eyeball.
6 . _ The image display device according to item 1. An optometry device comprising the optical device according to any one of claims 1 to 5 or the image display device according to any one of claims 6 to 10 .

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