JP3320471B2 - Holographic display system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a holographic display system . In particular, the present invention relates to a holographic display system that projects information necessary for a driver, such as speed, through a windshield of a vehicle such as a vehicle or an aircraft.

[0002]

As a method for information display to the driver or the like of the Related Art in the vehicle, a head-up display (hereinafter referred to as HUD)
Has recently been used. This optical information is projected from the light emitting display means such as a liquid crystal display device, reflects the combiner consisting of a half mirror or a hologram or the like provided in the windshield without the driver moves the almost line-of-sight from the operation state Information can be read.

[0003] In particular, those using a reflection type hologram as a combiner can diffract optical information toward a driver to form an image at an arbitrary position, and can produce a high-luminance display virtual image without deteriorating the foreground luminance. because there is obtained that feature, HU
The combiner of D is valid.

[0004]

As for the holographic display system used in the HUD, it is desirable that aberration and chromatic aberration relating to blur and distortion of the display virtual image are sufficiently removed, and furthermore, the fluctuation of the display virtual image due to the movement of the viewpoint. Is desirably removed. Further, when mounted on a vehicle or the like, it is desirable that the configuration be simple and compact in view of the vehicle space and the number of parts be small.

However, since the hologram is intended to be exposed by light from two directions emitted from the point light source, the virtual display image in which the optical information of the origination light display means having a finite size is made by the reflection-type hologram aberration Ji live about (particularly ends of) the blur or distortion, was not sufficient display image is obtained as HUD.

Further, for example when mounting a holographic display system on a vehicle or the like, but mainly the reflection hologram is Ru provided windshield of the vehicle, the inclination of the windshield is determined by vehicle type, commensurate with the inclination angle must be arranged a light-emitting display device as light is irradiated, there is a limit to the arrangement position or the like for the space of the vehicle is small, in the mutual positional relationship between the reflection hologram and the light emitting display means naturally was Tsu limit there.

[0007] When the reflection hologram is irradiated with light rays from the light-emitting display means under such restrictions, aberrations such as blur and distortion occur in the display virtual image formed by the reflection hologram.
There was that drawback.

Therefore, in consideration of the above exposure conditions and arrangement conditions, a reflection hologram is formed or a reflection hologram is formed so that aberrations relating to blur and distortion of a display virtual image formed by the reflection hologram are corrected. It has been proposed to reduce the aberration of the display virtual image by appropriately determining the distance and angle from the light-emitting display means under severe restrictions.

However, when viewing the viewer a virtual display image by reflection hologram, the light emitting display means for emitting light containing information to be obtained is the viewer, to emit light rays comprising a uniform wavelength distribution In the case where the wavelength of the light beam emitted to some extent varies, even if the reflection hologram itself is exposed and arranged so as not to cause aberration in the display virtual image, the reflection hologram itself may be transmitted from the light emitting display means as described above. aberration had occurred in the display virtual image rays is made is irradiated to the reflection-type hologram.

An object of the present invention is to provide Hisage novel holographic display system that solves the drawbacks described above that the prior art had.

[0011]

The present invention SUMMARY OF THE INVENTION has been made in view of the problems described above, a light emitting display means for generating a light beam including information, reflectively diffracted toward the light beam to the viewer It provided to so arranged the a reflection type hologram at least, a holographic display system capable of viewing the virtual display image formed by the reflection hologram image viewer, the light emitting display means, a light beam a light source for generating and a display member to include information on the light beam from the light source has at least a, unlike the wavelength of light emitted from each point of the display surface of the display body at each of points,
Occurs when the wavelength of light emitted from the display is uniform
Distortion in the opposite direction to that of the display image
Ru holographic display system der characterized that you have wavelength distribution of the light beam are determined.

[0012]

[0013]

According to the present invention, since the light beams emitted from the light-emitting display means have different wavelengths at each point on the display surface of the display body, the display virtual image formed by the reflection hologram is exposed to the light of the reflection hologram itself. can aberrations such as distortion which was caused by the mutual arrangement of the conditions and light-emitting display device in the opposite direction in compensation,
As a result, the viewer is cut in certified seen without display virtual image aberration.

[0014] Specifically, if may shift the position of the virtual display image downward toward the periphery from the center of the virtual display image,
Since the display virtual image formed by the reflection hologram is shifted upward as the wavelength of the light incident on the reflection hologram and diffracted becomes shorter, the aberration of the display virtual image is reduced by shortening the wavelength of the light from the periphery of the display body. you reduce.

In particular, when the light-emitting display means is provided with a narrow-band transmission interference filter, the light emitted from the light source of the light-emitting display means is incident on each point on the surface of the narrow-band transmission interference filter at a different angle, so that the light is narrowed. Light rays obliquely incident on the surface of the band-pass interference filter are transmitted through the narrow-band transmission interference filter because they have shorter wavelengths than the light rays incident perpendicularly to the surface of the band-pass interference filter. The light beam emitted toward each point has a different wavelength at each point on the display surface of the display body, and the aberration of the display virtual image formed by the reflection hologram is corrected.

[0016] In the case of mounting the light emitting display means or RaHitoshi one wavelength distribution emitted sulfo b graphics display system in a vehicle or the like, but mainly the reflection hologram is Ru provided windshield of the vehicle, The inclination of the windshield is determined by the type of vehicle, and when the light-emitting display means is arranged so that light rays are emitted as an angle corresponding to the inclination or the distance to the reflection hologram, the display of the light-emitting display means is displayed. Light is emitted from the surface so that there is no variation in wavelength at each point on the surface, so that aberrations such as distortion of a display virtual image are reduced.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a conceptual diagram showing an example of the holographic display system of the present invention. The light-emitting display means 1 and the reflection hologram 2 are arranged with a distance s ₁ therebetween, and a display virtual image 3 to be formed is formed at a distance s ₂ from the reflection hologram 2. Further, the angle of the display surface of the light-emitting display device 1 and the surface of the reflection hologram 2 is alpha _1, the virtual display image 3 formed surface and the reflection hologram 2
The angle between the surface have a alpha _2, the viewer 10 views the virtual display image 3 in the extension of the virtual display image 3 and the reflection hologram 2.

At each point on the display surface of the display body of the light emitting display means 1, the light rays emitted from the light emitting display means 1 have different wavelengths, and the exposure conditions of the reflection hologram are not sufficient, or wavelength distribution of the light from the display body so distorted distortion and reverse virtual display image generated when it is not possible to arrange the light-emitting display device at the position of Tokoro <br/> Nozomu are determined.

FIG. 2 is a schematic diagram showing an example of the wavelength distribution of light rays emitted from the display surface of the display of the light emitting display means in the present invention. The wavelength distribution of light emitted from the central portion A of the display surface of the light emitting display means is indicated by a solid line, the wavelength distribution of light emitted from the peripheral portion B of the display surface is indicated by a short broken line, wavelength distribution of the rays of light emitted from the peripheral edge portion C is indicated by long dashed lines.

In this case, as compared with the central portion A, the peripheral portions B,
C has a shorter wavelength. On the other hand, a light beam with a short wavelength shifts upward at a position of a display virtual image than a light beam with a long wavelength, and as a result, the display virtual image formed by the reflection hologram can return the downward shift of the peripheral portion upward. it can.

FIG. 3 is a conceptual diagram showing an example of the light emitting display means in the present invention. The light-emitting display means 1 has a light source 11 and a display 12, and a light beam from the light source 11 is emitted toward the display 12. The light source 11 and the display 1
2, a narrow-band transmission interference filter 13 is interposed, and a light beam emitted from the light source 11 is perpendicularly incident on the filter surface at a central portion of the narrow-band transmission interference filter 13. The light enters the filter surface obliquely toward the portion. The light transmitted through the narrow-band transmission interference filter 13 is substantially uniformized at a wavelength suitable for the selectivity of the reflection hologram, but the light obliquely incident on the filter surface of the narrow-band transmission interference filter 13 is vertically The light transmitted through the narrow-band transmission interference filter 13 and having a shorter wavelength than the incident light is transmitted to the display body because the light is transmitted to the display body at a peripheral portion of the light having a shorter wavelength. Will be done.

FIG. 4 is a conceptual diagram showing another example of the light emitting display means in the present invention. FIG. 4A shows a case where the light source is closer to the lens than the focal position (focal length f) of the lens.
FIG. 4B shows a case where the light source is farther from the lens than the focal position of the lens.

More specifically, the light emitting display means 1 includes a light source 11
, A display 12, a narrow-band transmission interference filter 13, and a lens 14, and the light source 11 is disposed at a position closer to or farther from the lens 14 than the focal position of the lens 14. The display body 1 is located on the side of the lens 14 opposite to the light source 11.
2 is not arranged, narrow band pass interference filter 13 between the lens 14 and the display body 12 is interposed.

The light beam emitted from the light source 11 is
The light source 11 is refracted by 4 and enters the narrow-band transmission interference filter 13. However, since the position of the light source 11 is closer to or farther from the lens than the focal position of the lens 14 (that is, the light source is not at the focal position of the lens), The refracted light is obliquely incident on the filter surface in the periphery of the narrow-band transmission interference filter 13.

In the above embodiment, the diameter of the lens is about 50 mm, and the focal length of the lens is 100 mm.
Is a degree, the size distribution is the position and the lens of the lenses is not limited to the above embodiments, can change the angle of incident on the narrow band pass interference filter according to the degree of distortion of the corrected are displayed virtual image as Ru is appropriately determined.

FIG. 5 is a conceptual diagram showing another example of the light emitting display means in the present invention. The light emitting display means 1 includes a light source 11
The light beam emitted from the light source 11 is incident on the incident end of the fiber bundle 15.

[0027] In the above embodiment, the distance to the narrow band pass interference filter from the output end of the fiber bundle is about 30 to 50 mm, also the diameter of the fiber bundle but is about 10 mm, the distribution of these fibers bundles The position (distance from the exit end to the narrow-band transmission interference filter, etc.) and the numerical aperture of the fiber bundle are not limited to those in the above-described embodiment. Ru appropriately determined to be able to change the angle of.

The narrow band transmission interference filter 13 is used for the display 1
Are interposed between the 2 and the fiber bundles 15, light rays radially emitted from the emission terminal of the fiber bundle 15, to filter surface of the narrow band pass interference filter 13, the central portion vertically periphery obliquely Incident on. The light beam entering the narrow-band transmission interference filter 13 is transmitted through the light beam emitted from the peripheral portion with a wavelength shorter than that of the central portion, and is emitted toward the reflection hologram via the display.

In the present invention, when a light beam having a uniform wavelength distribution is applied to the reflection hologram, the peripheral portion of the display virtual image formed by the reflection hologram is lowered depending on the position of the light emitting display means and the position of the reflection hologram. When it is determined from the simulation result by the numerical analysis that the position is shifted, the wavelength of the light beam emitted from the peripheral portion of the light emitting display means is made shorter than the wavelength emitted from the central portion, so that the peripheral portion of the display virtual image rises upward. However, when it is determined that aberration occurs such that the peripheral portion of the display virtual image originally formed by the reflection hologram is shifted upward, the peripheral portion of the display virtual image is shifted downward. In addition, by making the wavelength of the light beam emitted from the peripheral portion of the light emitting display means longer than the wavelength emitted from the central portion, the display imaginary is reduced. Aberrations can be corrected, can correct the aberration of the virtual display image by determining the wavelength distribution of the rays of light emitted from the light emitting display device according to various aberrations is determined from the other simulation results appropriately.

Further, in accordance with the exposure conditions of the reflection-type hologram, when the aberrations such as blurring or distortion in the virtual display image arranged in place of the reflection-type hologram and the emission display device so as to prevent light emitting display means It is desirable that the light rays emitted from the display have a uniform wavelength distribution at any point on the display surface of the display body.

[0031] FIG. 6 is a conceptual diagram illustrating a reference example of light emission display unit 1. As shown in FIG. 6A, the light beam emitted from the light source 11 is irradiated on the narrow-band transmission interference filter 13 by the lens 14 as a parallel light beam. Narrow band pass interference filter 13 rays transmitted through the reflection-type incident end as rays of wavelengths Tsu if the wavelength selectivity of the hologram is incident on the fiber bundle 15 close to the narrow band pass interference filter 13, the fiber bundle 15 It arranged from the output end for example as a position separated 30 to 50 mm (and only, Lena physician limited to this distance) is irradiated onto the display body 12.

In the display body 12, a light beam containing desired information is emitted toward the reflection type hologram. At this time, the light beam may be emitted with a wavelength distribution as shown in FIG.
Preferred . That is, the wavelength of the light beam emitted from the central portion A of the display surface of the display body and the wavelength of the light beam emitted from the peripheral portions B and C of the display surface are made uniform, and the reflection hologram is formed by such light beams. The displayed virtual image has reduced aberrations related to distortion, blurring, and the like.

[0033] As such another embodiment of the light-emitting display device 1, as shown in FIG. 6 (b), even without fiber bundle, parallel light rays light rays emitted from the light source 11 by the lens 14 Narrow band transmission interference filter 13
Light is irradiated includes information emitted from the display body 12 has a uniform wavelength at each point on the display surface of the display body 12.

As the narrow band transmission interference filter 13 used in the present invention, for example, a center wavelength of 515 n
m, the half-value width 10 nm, although those of transmittance of about 80% is preferably used, is not particularly limited thereto, Ru determined appropriately according to the exposure conditions of the reflection hologram used.

The distance between the light source and the narrow-band transmission interference filter is appropriately determined in consideration of the size of the light source, the size of the narrow-band transmission interference filter, the size of the light emitting display means itself, and the like . For example as long as the light emitting display means are provided on a vehicle or the like, but this interval is determined to be about 100 mm, Lena had particularly limited thereto.

[0036] Figure 8 is a conceptual diagram showing an example of an exposure method of making a reflection hologram, the hologram photosensitive material 21
A point light source 41 is provided at a position separated by R ₁ and R ₂ from, respectively, and spherical wave exposure is performed from both sides of the hologram photosensitive material 21 at incident angles of θ ₁ and θ ₂ respectively.

[0037] As the exposure conditions, for example, R ₁ = 80 0 m
_{m, R 2 = 100 0 mm} , θ 1 = 40 °, θ 2 = 60 °
A hologram photosensitive material is exposed to form a reflection hologram, s ₁ = 800 mm, s ₂ = 1000 mm,
When the reflection hologram and the light-emitting display means are arranged so that α ₁ = 40 ° and α ₂ = 60 ° (see FIG. 1), the display virtual image formed by the reflection hologram has aberrations such as blur and distortion. It is determined from the simulation result that no light is generated, and a reflection hologram display in which the aberration of the display virtual image is reduced by selecting a light emitting display means that emits light rays with a uniform wavelength on the display surface of the display body. You can get the system.

When the reflection hologram created under the above exposure conditions is used, if the value of s ₁ cannot be set to 800 mm due to the small space of the vehicle, the light emitting display means is used as a light emitting display means. By selecting one that emits light beams of different wavelengths on the display surface, it is possible to obtain a holographic display system in which the aberration of the display virtual image is reduced.

In view of the small space of the vehicle, the exposure conditions are, for example, R ₁ = 400 mm and R ₂ = 1.
If 000 mm, θ ₁ = 40 ° and θ ₂ = 60 °, the reflection hologram and the light-emitting display means are s ₁ = 400 m
m, s ₂ = 1000 mm, α ₁ = 40 °, α ₂ = 60 °
Holographic display system in which the aberration of the display virtual image is reduced by selecting a light emitting display means that emits a light beam with a uniform wavelength on the display surface of the display body. it can.

[0040] As the light emission display unit, there numerical analysis whether the aberration blur or distortion or the like on the virtual display image in the original can be placed a reflection hologram and the light emitting display means in a position that does not cause exposure conditions Is determined by the simulation according to the above, when it is determined that no aberration occurs in the display virtual image, the light emitting display means is selected so that the light emitted from the light emitting display means is emitted as a uniform wavelength from the display surface of the display body. , when the aberration in the virtual display image as a simulation result in the reverse is determined that arising, as its aberrations are reduced, rays of light emitted from the light emitting display means present invention
The holographic display system in which the aberration of the formed display virtual image is reduced can be obtained by appropriately selecting the light-emitting display means so that light rays having different wavelengths are obtained at each point on the display surface of the display body in the above.

Here, a case where the holographic display system of the present invention is mounted on a vehicle will be described.
FIG. 9 is a conceptual diagram in which the holographic display system of the present invention is mounted on a vehicle, and a light-emitting display means is provided below the windshield 61 of the vehicle. but that Hassu information to be displayed in a different wavelength or uniform wavelength by a point on the display surface of the display through the display body 12 as ray. The vehicle windshield 61, the reflection-type hologram 2 is provided with, light described above is diffracted is irradiated to the reflection hologram 2, Ru is visible in a viewing position of the viewer 10.

The information to be displayed in the present invention is appropriately selected by the display application. Speed meter of a vehicle, a tachometer, but more like a variety of warning lamps can be mentioned as an example, when the light-emitting display device of the present invention is not shall be provided in a vehicle is required to viewer if necessary Information is appropriately determined. The observer is mainly a driver of the vehicle, but may also include a passenger and other passengers, and all of them.

The reflection type hologram usually has an area of about several tens of mm square to several hundred mm square, a thickness of about several tens μm, and has a light diffraction function. As the reflection hologram, those called reflection holograms such as an emboss type and a Lippmann type can be widely used . Further, as the reflection hologram material, polyvinyl carbazole,
Various photosensitive materials such as dichromated gelatin, photo resist, photopolymer, silver salt and the like can be used .

Such a reflection type hologram is provided on the windshield, and may be provided, for example, on the surface of the windshield (outside surface of the vehicle) or the inside surface of the vehicle. However, in view of protection of the reflection type hologram. It is preferable to be used by being enclosed in a windshield which is a laminated glass. Between the reflection hologram and the light emitting display means provided in the windshield interposed further several sheets of holograms
May have, an optical member such as a reflector or lens may be <br/> intervene.

The light-emitting display means of the present invention has a function of emitting light for display, and a hot cathode tube (HC) is provided on a display comprising a so-called light-receiving display element such as a liquid crystal display element.
T), irradiates light emitted from a light source such as a fluorescent display tube (VF), a halogen lamp, an LED, or the like , or may have a combination of these functions. As the liquid crystal display device, a transmission type twist Ted Nemachi'<br/> click type liquid crystal display device, super twisted Ted nematic liquid crystal display element or the like can be preferably used.

[0046]

According to the holographic display system of the present invention, the reflection-type limit and the time of exposure of the hologram, distribution and the location and reflection of a light emitting display means in the case of mounting a holographic click the display system on a vehicle or the like distribution is the position of the mold hologram, further wavelength aberration of the rays of light emitted from the light emitting display device as distorted reverse the distortion of the virtual display image arising by restriction such mutual positions and angle between them, the display of the light-emitting display device by different wavelengths at each point of the display surface of the body, kill aberrations such as distortion of the virtual display image with a low reduction.

[0047]

[0048] Thus, especially when the holographic display system of the present invention is provided in the HUD, the reflection hologram is blurred even only one, at a reduced virtual display image viewer is viewing sure aberrations such as distortion And the control of the wavelength distribution of the light emitting display means can be performed by a simple configuration.
System can be simplified and compact.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing an example of a holographic display system of the present invention.

FIG. 2 is a conceptual diagram showing an example of a wavelength distribution of a light beam emitted from a light emitting display surface of the light emitting display means according to the present invention.

FIG. 3 is a conceptual diagram showing an example of a light emitting display means according to the present invention.

FIG. 4 is a conceptual diagram showing an example of a light emitting display unit according to the present invention.

FIG. 5 is a conceptual diagram showing an example of a light emitting display unit according to the present invention.

Conceptual diagram showing a reference example of FIG. 6 is a light - emitting display means

Conceptual diagram illustrating a reference example of the wavelength distribution of light emitted from the light emitting display surface of FIG. 7 Luminous display means

FIG. 8 is a conceptual diagram showing an example of an exposure method for creating a reflection hologram.

FIG. 9 is a conceptual diagram showing an example in which the holographic display system of the present invention is mounted on a vehicle.

[Explanation of symbols]

1: light emitting display device 2: reflection hologram 3: the virtual display image 10: image viewer 11: light source 12: Display 13: narrow band pass interference filter 14: Lens 15: fiber bundle 41: the point light source 61: windshield

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-243689 (JP, A) JP-A-48-57647 (JP, A) JP-A-61-278820 (JP, A) JP-A-4- 283790 (JP, A) JP-A-4-303812 (JP, A) JP-A-4-303813 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G02B 5/32 G03H 1 /twenty two

Claims (5)

(57) [Claims] 1. A light-emitting display means for generating a light beam containing information, and at least a reflection hologram arranged so as to reflect and diffract the light beam toward a viewer , and formed by the reflection hologram. a holographic display system adapted to display a virtual image that is visible to the viewer, the light emitting display means, at least chromatic a light source for generating a light beam, and a display member to include information on the light beam from the light source If you are, unlike the wavelength of light emitted from each point of the display surface of the display body in each respective points, emitted from the display body
This is the opposite of the display image distortion that occurs when the wavelength of the light beam is uniform.
The wavelength distribution of the light beam from the display is determined so that it is distorted in the direction
Is it holographic display system according to claim Rukoto. 2. A light beam emitted from a central portion of the display surface among light beams emitted from respective points on the display surface of the display body is a table.
Holographic display system according to wavelength than light emitted from the peripheral portion of示面 is short I請 Motomeko 1. 3. A light beam emitted from a central portion of the display surface among light beams emitted from each point on the display surface of the display body is a table.
Holographic display system according to the length I請 Motomeko 1 wavelength than light emitted from the periphery of the 示面. 4. Over permeable narrowband between the display body and the light source
Interference with the filter is not interposed, you incident at different angles at each point of the light beam narrowband transparently interference <br/> Wataru filter surface is emitted from the light source enters the narrowband transparently interference filter 請 < The holographic display system according to claim 1, 2 or 3. 5. have fiber bundles or lens between the narrow band pass interference filter and said light source is interposed
Holographic display system according to claim 4 that.