JPH06171395A - Luminous display device - Google Patents

Abstract

PURPOSE:To reduce the aberration such as dimness and distortion of a display virtual image by correcting the distortion and the like of the display virtual image, generated by the mutual disposition of a luminous display device and a hologram and the limitation of angles and the like, in such a way as to be distorted reversely by the different wavelength on each point of the display face. CONSTITUTION:A luminous display device 1 is formed of light source 11 and a display 12, and the beams of light from the light source 11 are emitted toward the display body 12. When a narrow-band transmission filter 13 is interposed between the light source 11 and the display body 12, the obliquely incoming beams of light onto the filter face of the narrow-band transmission filter 13 are transmitted in short wavelength compared to the vertically incoming beams of light. The beams of light transmitted through the narrow-band transmission interference filter 13 to irradiate the display body 12 and to proceed to a hologram come to have different wavelength at each point on the display face of the display body. Aberration such as dimness and distortion generated by the exposure condition of the hologram itself or the mutual disposition with the luminous display device 1 can be thereby corrected in the reverse direction so as to obtain a display virtual image without aberration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting display device which allows an observer to visually recognize a light beam containing information.

[0002]

2. Description of the Related Art A head-up display (hereinafter referred to as HUD) is used as a method of displaying information to a driver in a vehicle.
Has been used recently. This is because the optical information projected from a light emitting display device such as a liquid crystal display device is displayed on a combiner consisting of a half mirror and a hologram provided on the windshield so that the driver hardly moves his line of sight from the driving state. The information can be read.

In particular, a hologram using a hologram as a combiner is capable of diffracting optical information toward a driver and forming an image at an arbitrary position, and it has a high brightness without impairing the foreground brightness. It is effective as a combiner for HUD because it has a characteristic that a display virtual image can be obtained.

[0004]

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

However, since the hologram is exposed by the light from two directions emitted from the point light source, the optical information of the light-emitting display device having a finite size (particularly in the display virtual image formed by the hologram). An aberration relating to blurring or distortion is generated at the edge portion, and a sufficient display image cannot be obtained as a HUD.

Further, when a holographic display system is mounted on a vehicle, for example, the hologram is mainly provided on the windshield of the vehicle, but the inclination of the windshield is determined by the type of vehicle and is suitable for the inclination. It is necessary to arrange the light emitting display device so that the light beam is emitted at an angle, but there is a limitation in the arrangement position etc. due to the small space of the vehicle, and naturally the positional relationship between the hologram and the light emitting display device is also limited. Was caused.

When the hologram is irradiated with the light beam from the light emitting display device under such a limitation, there is a drawback that the virtual display image formed by the hologram has aberrations such as blurring and distortion.

An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide a light emitting display device which has not been known in the past.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and includes a light source which emits a light beam, and a display which receives the light beam from the light source and includes the information in the light beam. A light-emitting display device comprising at least the above, wherein the wavelength of the light beam emitted from each point on the display surface of the display body is different at each point.

Further, a narrow band transmission type interference filter is interposed between the light source and the display, and a light beam emitted from the light source and incident on the narrow band transmission type interference filter is narrow band transmission type interference filter. Provided is a light emitting display device, which is characterized in that light is incident at different angles at respective points on a surface.

Further, there is provided a light emitting display device characterized in that the wavelength of the light beam emitted from each point on the display surface of the display body is shorter in the peripheral portion than in the central portion of the display surface. Further, the present invention provides a light emitting display device characterized in that the wavelength of the light beam emitted from each point on the display surface of the display body is longer in the peripheral portion than in the central portion of the display surface.

Further, there is provided a light emitting display device characterized in that a fiber bundle is interposed between the light source and the narrow band interference filter. Further, there is provided a light emitting display device characterized in that a lens is interposed between the light source and the narrow band interference filter.

[0013]

According to the present invention, since the light rays emitted from the light emitting display device have different wavelengths at each point on the display surface of the display body, the display virtual image formed by the hologram shows the exposure conditions of the hologram itself and the light emitting display. Aberrations such as distortion caused by mutual arrangement with the device can be corrected in the opposite direction, and as a result, the observer can visually recognize a display virtual image without aberration.

Specifically, when the position of the display virtual image shifts downward from the center of the display virtual image toward the periphery, the display virtual image formed by the hologram has a short wavelength at which a light beam incident on the hologram and diffracted has a short wavelength. Since it shifts to the upper side, the aberration of the display virtual image is reduced by shortening the wavelength of the light beam from the peripheral portion of the display body.

Particularly, when the light emitting display device is provided with a narrow band transmission interference filter, a light beam emitted from the light source of the light emitting display device is incident on each point on the surface of the narrow band transmission interference filter at different angles, thereby narrowing the light. A light beam that enters obliquely as compared with a light beam that is incident perpendicularly to the surface of the band-pass interference filter has a shorter wavelength and is transmitted. The emitted light rays have different wavelengths at each point on the display surface of the display body, and the aberration of the display virtual image formed by the hologram is corrected.

[0016]

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 light emitting display device of the present invention. The light emitting display device 1 includes a light source 11 and a display body 12.
And the light from the light source 11 is emitted toward the display body 12. In addition, a narrow band transmission interference filter 13 is interposed between the light source 11 and the display body 12, and the light beam emitted from the light source 11 is incident on the central portion of the narrow band transmission interference filter 13 perpendicularly to the filter surface. Then, the light is obliquely incident on the filter surface toward the peripheral portion.

The light beam transmitted through the narrow band transmission interference filter 13 is almost uniformized to a wavelength matching the selectivity of the hologram, but the light beam obliquely incident on the filter surface of the narrow band transmission interference filter 13 is vertical. Since the wavelength of the light beam is shorter than that of the light beam that is incident on the light beam and is transmitted, the light beam that passes through the narrow band transmission interference filter 13 and is directed to the display body becomes a light beam having a short wavelength at its peripheral portion and is irradiated toward the hologram. Will be.

FIG. 2 is a schematic view showing an example of the wavelength distribution of the light rays emitted from the display surface of the display body of the light emitting display device of the present invention. The wavelength distribution of the light rays emitted from the central portion A of the display surface of the light emitting display device is shown by the solid line, and the wavelength distribution of the light rays emitted from the right peripheral portion B of the display surface is shown by the short dashed line,
The wavelength distribution of the light beam emitted from the left peripheral portion C of the display surface is shown by a long broken line.

In this case, as compared with the central portion A, the peripheral portion B,
C has a shorter wavelength. On the other hand, since the light ray having a short wavelength is displaced upward at the position of the display virtual image from the light ray having a long wavelength, as a result, the display virtual image formed by the hologram may return the downward displacement of the peripheral portion upward. it can.

Here, the narrow band transmission interference filter has a center wavelength of 515 nm, a half width of ± 5 nm, and a transmittance of 8
Although a 0% filter was used, it goes without saying that the filter is not limited to this.

FIG. 3 is a conceptual diagram showing another example of the light emitting display device of the present invention, and FIG. 3 (a) shows a case where the light source is closer to the lens than the focal position (focal length f) of the lens. ,
FIG. 3B shows the case where the light source is farther from the lens than the focal position of the lens.

Specifically, the light emitting display device 1 includes a light source 11
The display unit 12, the narrow band transmission interference filter 13 and the lens 14 are provided, and the light source 11 is arranged at a position closer to or farther from the lens 14 than the focal position of the lens 14. A display body 12 is provided on the opposite side of the lens 14 from the light source 11.
And a narrow band transmission interference filter 13 is interposed between the lens 14 and the display body 12.

The light beam emitted from the light source 11 is a lens 14
The light source 11 is refracted by the lens 14 and is incident on the narrow band transmission interference filter 13. In the peripheral part of the narrow band transmission interference filter 13, the formed light beam is obliquely incident on the filter surface.

In the above embodiment, the lens diameter is about 50 mm and the lens focal length is 100 mm.
However, the positions where these lenses are arranged and the size of the lenses are not limited to those in the above embodiment, and the incident light enters the narrow band transmission interference filter according to the degree of distortion of the display virtual image to be corrected. The angle to be set is appropriately determined so that the angle can be changed.

FIG. 4 is a conceptual diagram showing another example of the light emitting display device of the present invention. The light emitting display device 1 includes a light source 11, a fiber bundle 15, a display body 12 and a narrow band transmission interference filter 13, and a light beam emitted from the light source 11 is incident on an incident end of the fiber bundle 15.

The narrow band transmission interference filter 13 is the display 1
2 is interposed between the fiber bundle 15 and
Light rays radially emitted from the emission end of the fiber bundle 15 are incident on the filter surface of the narrow band transmission interference filter 13 at the central portion perpendicularly and obliquely at the peripheral portion. The light beam incident on the narrow band transmission interference filter 13 is transmitted with the wavelength of the light beam emitted from the peripheral portion being shorter than that in the central portion, and is transmitted toward the hologram through the display body.

In the above embodiment, the distance from the exit end of the fiber bundle to the narrow band transmission interference filter is about 30 to 50 mm, and the diameter of the fiber bundle is selected to be about 10 mm. The positions (distance from the emitting 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 embodiment, and the narrow band may be adjusted according to the degree of distortion of the display virtual image to be corrected. It is appropriately determined so that the angle of incidence on the transmission interference filter can be changed.

FIG. 5 is a conceptual diagram showing an example of a holographic display system incorporating the light emitting display device of the present invention. The light emitting display device 1 and the reflection hologram 2 are arranged at a distance of s _1. The formed display virtual image 3 is formed at a distance s ₂ from the hologram 2. Further, the angle formed by the light emitting element surface of the light emitting display device 1 and the hologram 2 surface is α ₁ , and the angle formed by the formed display virtual image 3 surface and the hologram 2 is α _2, and the observer 10 The display virtual image 3 is visually recognized on the extension line of the display virtual image 3 and the hologram 2.

At each point on the display surface of the display of the light emitting display device 1, the light rays emitted from the light emitting display device 1 have different wavelengths, and the exposure conditions of the hologram are not sufficient, or the hologram or the light emitting display device is The wavelength distribution of the light rays from the display body is determined so that the display virtual image is distorted in the direction opposite to that generated when it cannot be arranged at a desired position.

FIG. 6 is a conceptual diagram showing an example of an exposure method for producing a hologram of the present invention.
A point light source 41 is provided at positions separated by R ₁ and R ₂ from ₁ , respectively, and spherical wave exposure is performed from both surfaces of the hologram photosensitive material 21 at incident angles of θ ₁ and θ ₂ , respectively.

As exposure conditions, for example, R ₁ = 80 mm,
A hologram is formed by exposing the hologram photosensitive material with R ₂ = 100 mm, θ ₁ = 40 °, and θ ₂ = 60 °.
Under this exposure condition, if the value of s ₁ cannot be 800 mm because the space of the vehicle is small, aberrations such as blurring and distortion will occur in the display virtual image formed by the hologram. A holographic display system in which aberrations of a display virtual image are reduced can be obtained by using the light emitting display device according to (1) and a light emitting device that emits light rays of different wavelengths on the display surface of the display body.

According to the present invention, when a hologram is irradiated with a light beam having a uniform wavelength distribution, if a peripheral portion of a display virtual image formed by the hologram is displaced downward due to the arrangement of the light emitting display means and the hologram, numerical analysis is performed. When judged from the simulation result, the wavelength of the light beam emitted from the peripheral portion of the light emitting display device is set shorter than the wavelength emitted from the central portion, so that the peripheral portion of the display virtual image is corrected so as to shift upward. However, on the contrary, when an aberration occurs such that the peripheral portion of the display virtual image originally formed by the hologram is displaced upward, it is emitted from the peripheral portion of the light emitting display device so that the peripheral portion of the display virtual image is displaced downward. By making the wavelength of the light beam longer than the wavelength emitted from the center, it is possible to correct the aberration of the display virtual image. Wavelength distribution of the rays of light emitted from the light emitting display device according to various aberrations is determined from the simulation results can be corrected aberrations of the virtual display image by determining appropriate.

As described above, nothing is interposed between the light source and the narrow band transmission interference filter.
There is no particular limitation even if a lens, a fiber bundle, or the like is interposed, as long as the light beam emitted from the light source is incident at different angles on each point on the surface of the narrow band transmission interference filter.

The narrow band transmission interference filter 13 used in the present invention has, for example, a center wavelength of 515n.
m, half width ± 5 nm, and transmittance of about 80% are preferably used, but are not particularly limited thereto.
It is appropriately determined according to the exposure conditions of the 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, and the size of the light emitting display device itself. If the display device is provided in a vehicle or the like, this interval is set to about 100 mm, but it is not particularly limited thereto.

Here, a case where the light emitting display device of the present invention is mounted on a vehicle will be described. FIG. 7 is a conceptual diagram in which the light emitting display device of the present invention is mounted in a vehicle, and the light emitting display device is provided below the windshield 61 of the vehicle. Information that should pass through the display 12 and has a different wavelength or a uniform wavelength depending on a point on the display surface of the display is emitted as a light beam. The windshield 61 of the vehicle body is provided with the reflection hologram 2, and the above-mentioned light beam is applied to the hologram 2 to be diffracted and visually recognized at the observation position of the observer 10.

Here, the information to be displayed in the present invention is appropriately selected according to its display application, and examples thereof include a vehicle speedometer, a tachometer, and various warning lamps. When the light emitting display means of the present invention is not provided in the vehicle, the information required by the observer is appropriately determined as necessary. The observer is mainly a driver of the vehicle, but can also include passengers other than the passenger seat, and all these persons.

The hologram is usually several 10 mm square to several 1
It has an area of about 00 mm square and a thickness of about several tens of μm, and has a light diffraction function. As this hologram, a so-called hologram such as an embossed type or a Lippmann type hologram can be widely used. As the hologram material, various photosensitive materials such as polyvinylcarbazole, dichromated gelatin, photoresist, photopolymer, and silver salt can be used.

Such a hologram is provided on the windshield, and for example, the surface of the windshield (the outer surface of the vehicle).
Although it may be provided on the inner surface of the vehicle or the inside of the vehicle, it is preferably used by being enclosed inside the windshield which is a laminated glass in view of the protection of the hologram. In addition, between the hologram provided on the windshield and the light emitting display device,
Furthermore, several holograms may be interposed and optical members such as a reflecting mirror and a lens may be interposed.

The light emitting display device according to the present invention has a function of emitting light to display, and a hot cathode tube (HC) is attached to a display body composed of a so-called light receiving display element such as a liquid crystal display element.
T), a fluorescent display tube (VF), a halogen lamp, an LED, or the like, which emits light emitted from a light source, or may have these functions together. As the liquid crystal display element, a transmission type twist nematic type liquid crystal display element, a super twist nematic type liquid crystal display element and the like can be preferably used.

[0041]

According to the light emitting display device of the present invention, there are restrictions on the exposure of holograms, the position of the light emitting display device when a holographic display system is mounted on a vehicle, and the arrangement of holograms. Position, and the wavelength of the light beam emitted from the light emitting display device so as to distort the aberration such as the distortion of the display virtual image caused by the limitation of the mutual position and angle between the two, and the display surface of the display body of the light emitting display device. By setting different wavelengths at the respective points, aberrations such as distortion of the display virtual image can be reduced.

Thus, in particular, the light emitting display device of the present invention is H
When provided in the UD, an observer can visually recognize a display virtual image with reduced aberration such as blurring and distortion even if only one reflection hologram is used, and the wavelength distribution of the light emitting display device can be easily controlled. It is possible to obtain a simple and miniaturized holographic display system that can be performed by the configuration.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing an example of a light emitting display device of the present invention.

FIG. 2 is a conceptual diagram showing an example of wavelength distribution of light rays emitted from a light emitting display surface of a light emitting display device of the present invention.

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

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

FIG. 5 is a conceptual diagram showing an example of a holographic display system incorporating the light emitting display device of the present invention.

FIG. 6 is a conceptual diagram showing an example of an exposure method for creating a hologram according to the present invention.

FIG. 7 is a conceptual diagram showing an example in which the light emitting display device of the present invention is mounted on a vehicle.

[Explanation of symbols]

 1: Light emitting display device 2: Reflection hologram 3: Display virtual image 10: Observer 11: Light source 12: Display body 13: Narrow band transmission interference filter 14: Lens 41: Point light source 61: Windshield

Claims (6)

[Claims] 1. A light emitting display device comprising at least a light source which emits a light beam and a display which receives the light beam from the light source and emits the light including information. A light emitting display device characterized in that the wavelengths of light rays emitted from points are different at each point. 2. A narrow band transmission type interference filter is interposed between the light source and the display body, and a light beam emitted from the light source and incident on the narrow band transmission type interference filter is of a narrow band transmission type interference filter surface. The light emitting display device according to claim 1, wherein light is incident at different angles at respective points. 3. The light emitting display device according to claim 1, wherein the wavelength of the light beam emitted from each point on the display surface of the display body is shorter in the peripheral portion than in the central portion of the display surface. 4. The light emitting display device according to claim 1, wherein the wavelength of the light beam emitted from each point on the display surface of the display body is longer in the peripheral portion than in the central portion of the display surface. 5. The light emitting display device according to claim 2, wherein a fiber bundle is interposed between the light source and the narrow band interference filter. 6. The light emitting display device according to claim 2, wherein a lens is interposed between the light source and the narrow band interference filter.