JP6941926B2 - Optical device - Google Patents

Description

The present invention relates to an optical device that can be used as a VCS (Variable cross cylinder).

A CC (Cross cylinder) is known as an optical device used for astigmatism inspection (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 05-176893

For astigmatism testing, it is necessary to rotate the cross cylinder. Normally, the rotation of the cross cylinder is performed manually or mechanically using a drive source such as a motor. There is also a method of preparing a plurality of cross cylinders and switching between them. In any case, a high-precision moving part for machine control is required, the cost is high, and the entire device becomes large. Moreover, since it is a precision machine, maintenance is required to maintain its performance. In addition, the manual method has problems such as the burden on the inspector and the variation in accuracy depending on the skill, and is not common in modern times.

Against this background, it is an object of the present invention to provide a cross cylinder that does not require a mechanical mechanism for rotation or switching.

The invention according to claim 1 is a pair of light-transmitting substrates arranged with a gap, a transparent polar liquid having a first refractive index enclosed between the pair of substrates, and the above-mentioned polar solution. A non-polar liquid that is separated from the polar liquid and is transparent and has a second refractive index, a transparent conductive film provided on one of the pair of substrates side for applying a voltage between the pair of substrates, and the other. The pair includes an electrode provided on the substrate side of the A voltage is applied between the substrates by the transparent conductive film and the electrode, and the electrodes are arranged radially on the peripheral portion of the active matrix electrode and the light-transmitting active matrix electrode arranged in the central portion. The lens includes a plurality of light-transmitting electrodes and is provided so as to extend to a region that effectively works as an optical member, and the lens is provided in the first radial direction by adjusting the in-plane distribution. It is an optical device having a first optical characteristic in the above, and having a second optical characteristic in a second radial direction different from the first radial direction.

The invention of claim 2 is the invention according to claim 1, characterized in that the cross cylinder is constituted by the shape of the interface between the polar liquid and the nonpolar liquid.

The invention according to claim 3 is characterized in that, in the invention according to claim 2 , the cross cylinder is rotated by changing the in-plane distribution of the voltage between the pair of substrates. The invention according to claim 4 is the invention according to claim 2 or 3 , characterized in that astigmatism information of the eye to be inspected is acquired from the control parameter of the cross cylinder.

The invention according to claim 5 is the invention according to any one of claims 1 to 4 , wherein the in-plane distribution of the voltage between the pair of substrates is controlled based on the astigmatism information of the eye to be inspected. The lens formed by the polar solution or the non-polar solution is used as an astigmatism correction lens for correcting astigmatism in the eye to be inspected.

According to the present invention, a cross cylinder that does not require a mechanical mechanism for rotation or switching can be obtained.

It is a principle diagram which shows the principle of an embodiment. It is a figure which shows the electrode structure of an embodiment. It is a block diagram of a control system. This is an example of a lens realized in the embodiment. This is an example of a lens realized in the embodiment. This is an example of an ophthalmic apparatus utilizing the invention.

(composition)
FIG. 1 shows a cross-sectional structure of a liquid optical device 100 utilizing the invention. The liquid optical device 100 can be used as a VCS (Variable cross cylinder). In the present specification, a cross cylinder is a lens having a power of two meridians of ± 0.50D, and a VCS (Variable cross cylinder) is a lens having a variable power of two meridians. The shape of the liquid optical device 100 when viewed from the direction of the optical axis has a substantially circular appearance. The liquid optical device 100 is configured by using a pair of glass substrates 121 and 122 arranged so as to face each other with a gap. The substrate may be other than glass as long as it is a material that transmits visible light. For example, a transparent plastic material can be used as the substrate.

The active electrode layer 123 and the high-dielectric film 124 are laminated on the lower glass substrate 121. FIG. 2 shows an outline of the active electrode layer 123 as viewed from the optical axis direction. In the active electrode layer 123, a circular region in the center is an active matrix electrode, and a region other than the center is a radial electrode. In the active matrix electrode, a plurality of electrodes are arranged in a grid pattern. The radial electrode has a shape in which 72 longitudinal electrodes are radially arranged at 5 ° intervals. The number of divisions of the radial electrode is not limited to the number illustrated in FIG. Increasing the number of divisions enables more accurate control, but the structure becomes complicated.

The active matrix electrode and the radial electrode constituting the active electrode layer 123 are composed of a transparent conductive film (ITO film), and each transparent conductive film is provided with the potential of the transparent conductive film (potential with respect to the opposing transparent conductive film 129). The thin film to be determined is connected. The structure around this is the same as that of the active matrix type liquid crystal display. It should be noted that each of the active matrix electrode and the electrode constituting the radial electrode can change the level of the applied voltage in addition to the presence or absence of the voltage application. The variable level of the applied voltage may be continuous or may be a plurality of stepwise steps.

Returning to FIG. 1, as the high-dielectric film 124, for example, PVdF (polyvinylidene fluoride) or PTFE (polytetrafluoroethylene) is used. A water-repellent film 125 is arranged in contact with the high-dielectric film 124. The water-repellent film 125 is a film having water repellency, and for example, Teflon AF (registered trademark) or Cytop is used.

The ring member 126 is arranged in contact with the water repellent film 125. The ring member 126 is a ring-shaped member, which is in contact with the water-repellent film 125 and the high-dielectric film 127, and an internal space 128 is formed inside the ring member 126. The upper high dielectric film 127 is in contact with the upper transparent conductive film (ITO film) 129, and the transparent conductive film 129 is in contact with the upper glass substrate 122. The transparent conductive film 129 is uniformly provided on the entire surface of a region that effectively works as an optical member. The periphery of the ring member 126 is sealed by a sealing material 130, and the internal space 128 is a closed space.

A hydrophilic film 131 is arranged on the side of the internal space 128 of the high-dielectric film 127. The hydrophilic film 131 is a film having a hydrophilic function, and is composed of an inorganic dispersion such as trisilanol or silica. The internal space 128 is filled with a transparent water-based polar liquid 132 and a transparent non-polar liquid 133. Specific examples of the polar liquid 132 include water, methanol, and the like. Examples of the non-polar liquid 133 include oils such as hydrocarbon-based synthetic oils and silicone oils. The polar liquid 132 and the non-polar liquid 133 are selected to be transparent, have a difference in refractive index, and have a property of separating without mixing with each other, such as water and oil. In this example, the refractive index of the non-polar liquid 133 is set to be higher than the refractive power of the polarized liquid 132, and the lens is formed by the portion of the non-polar liquid 133. Of course, by setting the refractive index of the non-polar liquid 133 to be smaller than the refractive power of the polarized liquid 132, the lens may be formed by the portion of the polar liquid 132.

As an example of the dimensions of each part, the size of the effective surface (region that effectively functions as a lens) of the liquid optical apparatus 100 is a circle with a diameter of about 25 mm to 40 mm, and the thicknesses of the glass substrates 121 and 122 are 0.1 to 0.1. 0.5 mm, the thickness of the high dielectric film 124 is 0.3 to 5 μm, the thickness of the water repellent film 125 is several to 500 nm, and the height of the internal space (distance between the water repellent film 125 and the hydrophilic film 131) is 0. .1 to 5 mm, the thickness of the high dielectric film 127 is 0.3 to 5 μm, the thickness of the hydrophilic film 131 is several to 500 μm, and the thickness of the transparent conductive film 129 is 10 to 200 nm. An example is given in which the dimensions of each part of the active electrode layer 123 are values adopted in a known active matrix substrate for a liquid crystal display.

The lens is composed of 133 parts of non-polar liquid. The shape of the lens composed of the non-polar liquid 133 can be controlled. For example, when a relatively high voltage is applied on the outer peripheral side of the active electrode layer 123 and a relatively low voltage is applied near the center, the lens composed of the non-polar liquid 133 has a cross-sectional shape shown in FIG. 1 (A). It becomes a convex lens. This is obtained as a result of the polar liquid 132 being concentrated on the outer peripheral side having a large electric field density, and the non-polar liquid 133 being concentrated near the center.

On the other hand, when a low voltage is applied on the outer peripheral side of the active electrode layer 123 and a high voltage is applied near the center, the lens composed of the non-polar liquid 133 becomes a concave lens having a cross-sectional shape shown in FIG. 1 (B). This is obtained as a result of the polar liquid 132 being concentrated on the central side having a large electric field density, so that the non-polar liquid 133 is thin in the vicinity of the center and thick in the outer periphery.

The electrodes constituting the active electrode layer 123 shown in FIG. 2 can individually adjust the voltage application level. Here, the profile of the voltage application in the cross section along the X-axis direction of FIG. 2 is in the form of obtaining the state of FIG. 1 (A), and the profile of the voltage application in the cross section along the Y-axis of FIG. 2 is shown. If the form is different from that of 1 (A), lenses having different shapes can be obtained in the cross section along the X axis and the cross section along the Y axis. Further, the position of the center of the convex lens or the concave lens can be eccentric from the center by adjusting the applied voltage distribution. Further, it is possible to realize a lens having a cross-sectional shape in which the symmetry is broken.

Further, in the above embodiment, by adjusting so that a voltage gradient in the Y-axis direction does not occur, the cross section along the X-axis is the convex lens of FIG. 1 (A), and the cross-section along the Y-axis functions as a lens. You can get a cylindrical lens that does not. An example of this cylindrical lens is shown in FIG. 4 (B).

According to the above principle, the function of the cross cylinder can be realized. In this configuration, a mechanical moving part is not required for the reversal and rotation of the cross cylinder, and the reversal and rotation of the cross cylinder are electrically controlled by a drive signal supplied to the active electrode layer 123.

In the case of the simplest control, the axial angle pitch (rotation angle pitch) of the cross cylinder in FIG. 2 is 5 ° (because the radial electrodes have a 5 ° pitch). In the active electrode layer 123 shown in FIG. 2, the rotation angle of the cross cylinder can be adjusted in steps finer than 5 °. However, in this case, it is necessary to change the potential of the radial electrode in multiple steps or continuously.

FIG. 4A shows an example of lenses having different spherical powers on two axes (two radial directions intersecting at 90 °) orthogonal to the optical axis. FIG. 4B shows an example in which a cylindrical lens (cylindrical lens) is realized. By adjusting the potential of each electrode of the active electrode layer 123, the lenses of FIGS. 4A and 4B can be realized. Although FIG. 4 shows a state in which the lens is cut into a rectangular shape so that the cross section can be easily understood, the shape of the lens when the liquid optical device 100 is actually viewed from the direction of the optical axis is circular. Depending on how the voltage is applied, an elliptical or distorted circular lens is also possible.

It is also possible to prepare two optical devices having the configuration of the liquid optical device 100 of FIG. 1 and use them in an overlapping manner on the optical axis. In this case, it is possible to obtain a lens in which the concave cylindrical lens and the convex cylindrical lens shown in FIG. 5 are arranged orthogonally. The lens of FIG. 5 can be applied to a lens for astigmatism correction.

(Control system)
The control system of the liquid optical device 100 will be described. FIG. 3 shows a control device 200 that controls the liquid optical device 100. The control device 200 has a function as a computer, and includes a CPU, a memory, and various interfaces. Although the arithmetic unit 200 is configured by using a general-purpose microcomputer, a part or all of the arithmetic unit 200 may be configured by a dedicated electronic circuit.

The control device 200 includes a parameter input unit 201, a calculation unit 202, and a control signal generation unit 203. The parameter input unit 201 inputs information on the S value, C value, and A value of the eye to be inspected. Here, the S value is the spherical power (-myopia, + hyperopia), and is the refractive power of the concave lens / convex lens used for correcting myopia or hyperopia. The C value is the astigmatism power, which is the refractive power of the cylindrical lens used for astigmatism correction. The A value is a numerical value of the angle at which the cylindrical lens for astigmatism enters between 1 ° and 180 °. The C value and the A value are parameters that define the state of astigmatism, and are examples of astigmatism information.

(First example)
By designating the S value, C value, and A value, a VCS (Variable cross cylinder) using the liquid optical device 100 can be obtained. The VCS using the liquid optical device 100 can electrically rotate the cross cylinder around the optical axis by electrical control. In the case of FIG. 2, the cross cylinder can be rotated in 5 ° steps. This rotation is controlled by a control signal supplied to the liquid optical device 100. At this time, only the polar liquid 132 and the non-polar liquid 133 that passively move in response to the movement of the polar liquid 132 physically move, and there is no place where the mechanical parts move.

Since the liquid optical device 100 can easily change one or more values of the S value, the C value, and the A value, the S value, the C value, and the S value, the C value, can be electronically changed without physically changing the lens. A lens in which one or a plurality of A values are changed can be realized by changing the shape of the non-polar liquid 133. Therefore, by using the liquid optical device 100, the cross-cylinder type optometry (astigmatism inspection) can be performed more efficiently. That is, in the cross-cylinder type optometry, the work of reversing and rotating the cross-cylinder is required, but in the liquid optical apparatus 100, this work is performed by electric control. Further, the constant can be easily changed (change of one or a plurality of values of S value, C value, and A value) by operating a switch or the like.

(Second example)
When the S value, C value, and A value of the eye to be inspected are known, a lens capable of correcting the states of myopia, hyperopia, and astigmatism of the eye to be inspected can be produced by using the liquid optical device 100. In this example, the S value, C value, and A value input to the parameter input unit 201 are sent to the calculation unit 202. The calculation unit 202 calculates a lens shape capable of correcting these values to a predetermined value based on the input S value, C value, and A value. The relationship between the S value, the C value, and the A value and the desired lens shape has been investigated in advance, and the data is stored in the memory of the control device 200. Based on this data, the calculation unit 202 calculates the shape of the lens.

Further, the relationship between the shape of the lens and the voltage applied to each electrode in the liquid optical device 100 has also been investigated in advance, and the data is stored in the memory of the control device 200. Based on this data, the control signal generation unit 203 generates a control signal to be sent to the liquid optical device 100, and the liquid optical device 100 forms a lens having a shape calculated by the calculation unit 202.

According to this technique, a lens for correction suitable for the eye to be inspected can be produced by the liquid optical apparatus 100 by electrical processing based on the S value, C value, and A value of the eye to be inspected. Further, since it is possible to make fine adjustments in the optical axis direction of the lens, it is possible to obtain a lens in which optical characteristics that cannot be pursued by the S value, C value, and A value are adjusted according to the eye to be inspected.

(Third example)
FIG. 6 shows the optometry device 400. The optometry device 400 has a function of performing astigmatism optometry (of course, it may have other optometry functions). The optometry device 400 includes a liquid optical device 100A and a liquid optical device 100B having the same structure and function as the liquid optical device 100 of FIG. Each of the liquid optical device 100A and the liquid optical device 100B is individually controlled by the control device 200 shown in FIG.

The optometry device 400 includes a parameter calculation unit 300. The parameter calculation unit 300 calculates the C value and the A value of the eye to be inspected. The C value is the astigmatism power, which is the refractive power of the cylindrical lens used for astigmatism correction. The A value is the angle at which the cylindrical lens for astigmatism enters. The optometry device 400 also has a function of inspecting the S value (spherical power (-myopia, + hyperopia)), but since this is the same as the existing optometry device, the description thereof will be omitted.

The inspection of the C value and the A value is performed as follows. The liquid optical devices 100A and 100B have a cross-cylinder function capable of changing the setting of the angular position and the power. Using this function, an eye examination using a cross-cylinder optotype is performed to obtain a C value and an A value. The method of obtaining the C value and the A value is the same as in the case of the known cross cylinder test. The left and right cross cylinders are not inspected at the same time, and the cross cylinder optotypes are displayed one eye at a time for inspection.

That is, the power of the cylindrical lens realized there can be calculated from the control parameters of the liquid optical devices 100A and 100B when the optimum cylindrical lens is selected in the cross cylinder test. This is the calculation principle of the C value (astigmatism power: refractive power of the cylindrical lens used for astigmatism correction). Further, in the above state, the angle with respect to the reference direction (for example, the vertical direction) of the cylindrical lens realized therein can be calculated from the control parameters of the liquid optical devices 100A and 100B. As a result, the A value can be obtained. In this way, the parameter calculation unit 300 calculates the C value and the A value of each of the left and right eyes to be inspected.

After calculating the C value and the A value, the data are input to the control device 200 together with the separately acquired S value, and the corrective lens suitable for the eye to be inspected is set to the liquid optical devices 100A and 100B by the control described in connection with FIG. Realized in.

A specific example will be described below. For example, as a result of the above cross-cylinder test, it is assumed that the S value: +1.00 degrees, the C value: +1.00 degrees, and the A value: 180 ° for the eye to be inspected. In this case, the active electrode layer 123 is electronically controlled so that the lens shape corresponds to the S value: +1.00 degrees, the C value: +1.00 degrees, and the A value: 180 °, and the potential of each electrode is adjusted. do. As a result, the shape of the non-polar liquid 133 is different in the orthogonal radial direction (see, for example, FIG. 4), and a lens for astigmatism correction corresponding to the above S value, C value, and A value can be obtained.

(Conclusion)
As described above, the liquid optical device 100 shown in FIG. 1 is a transparent first lens encapsulated between a pair of glass substrates 121 and 122 arranged with a gap and a pair of glass substrates 121 and 122. A polar liquid 132 having a refractive index of 1 and a non-polar liquid 133 which is transparent and has a second refractive index separated from the polar liquid 132, an electrode for applying a voltage between the glass substrates 121 and 122, and a glass having the above voltage. A control unit 200 (see FIG. 3) that controls the in-plane distribution between the substrates 121 and 122 and a lens formed by the polar liquid 132 or the non-polar liquid 133 are provided, and the lens adjusts the in-plane distribution. As a result, it has a structure that has the first optical characteristic in the first radial direction as illustrated in FIG. 4 and exhibits the second optical characteristic in the second radial direction different from the first radial direction. ..

This configuration provides a cross cylinder that does not require a mechanical mechanism for rotation or switching. Further, since the shape of the lens can be changed electrically, a lens for astigmatism correction can be obtained based on astigmatism information such as C value and A value.

100 ... Liquid optical device, 100A ... VCS for left eye, 100B ... Liquid optical device for right eye, 121 ... Glass substrate, 122 ... Glass substrate, 123 ... Active electrode layer, 124 ... High dielectric film, 125 ... Water repellent Membrane, 126 ... Ring member, 127 ... High dielectric film, 128 ... Internal space, 129 ... Transparent conductive film, 130 ... Encapsulant, 131 ... Hydrophilic film, 132 ... Polarized liquid, 133 ... Non-polar liquid, 400 Ophthalmic apparatus ..

Claims (5)

A pair of light-transmitting substrates arranged with a gap,
A transparent polar liquid having a first refractive index and a non-polar liquid separated from the polar liquid and having a second refractive index, which are sealed between the pair of substrates.
A transparent conductive film provided on one of the pair of substrates side for applying a voltage between the pair of substrates, and an electrode provided on the other substrate side.
A control unit that controls the in-plane distribution of the voltage between the pair of substrates,
With a lens formed of the polar or non-polar liquid,
A voltage is applied between the pair of substrates by the transparent conductive film and the electrodes.
The electrode includes a light-transmitting active matrix electrode arranged in the central portion and a plurality of light-transmitting electrodes arranged radially on the peripheral portion of the active matrix electrode, and extends to a region effectively working as an optical member. It was set up to be there,
The lens has a first optical characteristic in the first radial direction and a second optical characteristic in a second radial direction different from the first radial direction by adjusting the in-plane distribution. An optical device characterized by that. The optical device according to claim 1, wherein a cross cylinder is formed by the shape of the interface between the polar liquid and the non-polar liquid. The optical device according to claim 2, wherein the cross cylinder is rotated by changing the in-plane distribution of the voltage between the pair of substrates. The optical device according to claim 2 or 3, wherein the astigmatism information of the eye to be inspected is acquired from the control parameter of the cross cylinder. By controlling the in-plane distribution of the voltage between the pair of substrates based on the astigmatism information of the eye to be inspected, the lens formed by the polar liquid or the non-polar liquid corrects the astigmatism of the eye to be inspected. The optical device according to any one of claims 1 to 4, wherein the lens is for correcting astigmatism.

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