JP6762065B2 - Full-color high-resolution computer synthetic hologram display device, its manufacturing method and its manufacturing device - Google Patents

Description

The present invention relates to a hologram display device, a manufacturing method thereof and a manufacturing device thereof, particularly a full-color high-resolution computer composite hologram display device, a manufacturing method thereof and a manufacturing device thereof.

In order to generate a three-dimensional stereoscopic image by color holography, in conventional optical holography, it is necessary to irradiate an object with a three-color laser beam in a dark room and record interference fringes on a recording material. This shooting requires an extremely high level of skill.

In addition, only real objects can be recorded and reproduced by the method described above, and non-real virtual objects (for example, computer graphic data) and large objects (for example, buildings) that cannot be irradiated with laser light can be recorded. Is difficult to visualize.

On the other hand, a computer-generated hologram (CGH) is characterized in that it can reproduce non-existent objects and scenes represented by numerical data. A method of using a color filter for colorizing CGH has been conventionally proposed. For example, Patent Document 1 discloses a method using a spatial light modulator and a color filter. However, in the current spatial light modulator, the display resolution is insufficient by three digits or more in order to obtain a high-quality three-dimensional stereoscopic image, and a high-quality image cannot be obtained even if a large-scale device is used. Further, Patent Document 2 also discloses a reproduction method using a color filter, but the reproduction method is premised on the use of a coherent light source or a complicated optical circuit by a laser device, and is actually exhibited and appreciated. It is very difficult to create a possible hologram.

On the other hand, the inventors of the invention according to the present application calculate an ultra-high resolution CGH of 10 billion pixels or more that can be actually exhibited and viewed, and etch a chrome film on a glass substrate to obtain high-contrast interference fringes. By obtaining it, a high-quality 3D stereoscopic image is obtained by reflecting or transmitting and reproducing it using a simple LED light source. In fact, these CGHs reproduce images with a sense of depth and natural motion parallax that cannot be expressed by conventional stereoscopic image technology (see Non-Patent Documents 1 to 3). However, since this image is obtained by monochromatic light, it is difficult to reproduce it with a white light source or to make it full color.

Therefore, Non-Patent Document 4 discloses an apparatus for color reproduction by synthesizing the reproduction light of three holograms by an optical system. However, it is difficult to actually exhibit because the equipment becomes large.

Japanese Unexamined Patent Publication No. 2008-281774 Japanese Unexamined Patent Publication No. 8-201630 JP-A-2008-122668

K. Matsushima, et al., Appl. Opt. 48, H54-H63 (2009) K. Matsushima, et al., J. Electron. Imaging 21, 023002 (2012) Matsushima, HODIC Circular 32, No. 2, 31-40 (2012) Miyaoka, Matsushima, Nakahara, 3D Image Conference 2014, P-13, (2014)

The present invention is a full-color three-dimensional display that can be exhibited and viewed by a non-coherent LED light source or a white light source using an ultra-high resolution computer composite hologram of 10 billion pixels made of a high-contrast metal reflective film and a color filter. It is an object of the present invention to provide a hologram display device for displaying a stereoscopic image and a method for producing the same.

Further, the present invention is a method for manufacturing a hologram display device using a volumetric hologram generated by transfer, and a method for manufacturing the hologram display device for displaying a full-color three-dimensional stereoscopic image, and a method for manufacturing the hologram display device. The device is intended to be provided.

The present invention has been made to achieve the above object. The hologram display device according to the present invention is
A metal film with interference fringes and
A color filter composed of a combination of color filter segments of multiple colors,
Includes the metal film and a reference light source that illuminates the color filter.
The interference fringes of the metal film are formed corresponding to the individual color filter segments constituting the color filter.
In the interference fringes of the metal film corresponding to the portions where the color filter segments of different colors are adjacent to each other, a guard gap for guarding the illuminated reference light is provided.

By utilizing the present invention, a full-color three-dimensional stereoscopic image that can be exhibited and viewed is displayed by using an ultra-high resolution computer composite hologram of 10 billion pixels made of a high-contrast metal reflective film and a color filter. A hologram display device can be obtained. Further, by utilizing the present invention, a full-color high-resolution computer composite hologram display device that can be mass-produced and has excellent wavelength selectivity and angle selectivity can be transferred using an ultra-high resolution computer composite hologram and a color filter. Can be obtained by

It is a figure which shows the manufacturing method of the hologram display device which concerns on 1st Embodiment of this invention. It is a figure which shows typically the structure of the hologram display device which concerns on 1st Embodiment of this invention. FIG. 3A is a diagram showing an example of the spectral characteristics of the phosphor-type white LED that has passed through the color filter twice. FIG. 3B is a diagram showing an example of the spectral characteristics of the multi-chip color LED that has passed through the color filter twice. It is a figure for demonstrating the positional relationship between the color filter and the interference fringe layer in the hologram display device which concerns on 1st Embodiment of this invention. It is a figure which shows the pixel block composition of the color filter in the hologram display device which concerns on 1st Embodiment of this invention. It is a figure which shows the outline of the drawing method by the lithography using the laser drawing apparatus or the electron beam drawing apparatus. It is a figure for demonstrating the positional relationship between the color filter and the interference fringe layer in the hologram display device which concerns on 1st Embodiment of this invention. FIG. 8A is a diagram showing an interference fringe layer without a guard gap. FIG. 8B is a diagram showing an interference fringe layer provided with a guard gap. FIG. 9A is a diagram showing the effect of the guard gap in a configuration used as a reflective hologram display device. FIG. 9B is a diagram showing the effect of the guard gap in a configuration used as a transmissive hologram display device. It is a figure which shows the color filter which a plurality of segments form a horizontal stripe. It is a figure which shows the reflection type hologram display device which used the amplitude modulation of light, and the reflection type hologram display device which used the phase modulation of light. FIG. 12A is a simplified diagram showing an imaging (recording) form of a conventional transmissive hologram. FIG. 12B is a simplified diagram showing an imaging (recording) form of a conventional reflective hologram. FIG. 12 (c) is a simplified diagram showing an imaging (recording) form of a Denishuk-type volumetric hologram. FIG. 13 (a) is a schematic vertical sectional view of a thin hologram. FIG. 13B is a schematic vertical sectional view of a volumetric hologram (thick hologram). It is a schematic diagram which shows the state of reproduction of the original plate CGH of a metal film high resolution used in the production by transfer | transfer of the Denishuk type volumetric hologram which concerns on 3rd Embodiment. It is the schematic which shows the state of transfer to the recording material of the metal film high-resolution original CGH. It is a figure which shows the manufacturing method and manufacturing apparatus of the full-color high-resolution computer synthetic hologram display apparatus which makes the Denishuk type volumetric hologram produced by transfer of 1st form full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of the full-color high-resolution computer synthetic hologram display apparatus which makes the Denishuk type volumetric hologram produced by transfer of 2nd form full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of the full-color high-resolution computer synthetic hologram display apparatus which makes the Denishuk type volumetric hologram produced by transfer of 3rd form full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of the full-color high-resolution computer synthetic hologram display apparatus which makes the Denishuk type volumetric hologram produced by transfer of 4th form full-color.

Hereinafter, preferred embodiments according to the present invention will be described with reference to the drawings.

[First Embodiment]
1. 1. Configuration of Hologram Display Device FIG. 2 is a diagram schematically showing a configuration of a hologram display device according to the first embodiment of the present invention. FIG. 1 is a diagram showing a method of manufacturing a hologram display device according to the first embodiment of the present invention.

1.1. Configuration of Color Filter Method The hologram display device shown in FIG. 2 uses a color filter 4 to display a full-color computer composite hologram (CGH) by the interference fringe layer 2 of a single plate. In the production of the color filter type full-color computer composite hologram display device according to the first embodiment, first, the interference fringe layer 2 of the single plate is spatially divided into RGB blocks (2r, 2g, 2b) to interfere with each color. Draw stripes. The interference fringes are formed on the metal layer 8 as will be described later. Subsequently, color filters (4r, 4g, 4b) of colors corresponding to each of the RGB blocks are attached to the metal film on which the interference fringes are formed and juxtaposed. The color filter type full-color computer composite hologram display device according to the first embodiment performs full-color reproduction by irradiating the juxtaposed interference fringe layers 2 and the color filter 4 with white light as reference light. This white light is emitted from the white light source (reference light source) 100. The reproduced illumination light of each color that has passed (or passed through) the color filter 4 illuminates the corresponding block, so that the image of each color is reproduced. In general, since a hologram has a characteristic that it can be reproduced even from a part of interference fringes, color reproduction becomes possible by synthesizing images of each color.

The high-precision color filter 4 can be created by various methods. For example, it can be created by a digital silver halide laser printing technique in which image data is drawn directly on a reversal film using a three-primary color laser. By this method, various color filter patterns can be easily and highly accurately created.

1.2. Configuration of White Light Source First, the white light source 100 that irradiates white light as reference light will be described. It is desirable that each of the RGB illumination lights of the white light source 100 has a narrow band. This is because if the band is wide, chromatic aberration occurs in each color, and the image (holography) is blurred. In general, color filters have a wide band and low wavelength selectivity. Therefore, it is desirable that the light source be a laser (ie, monochromatic light) if possible. However, it is not desirable to use a laser for exhibition and viewing. Therefore, in the hologram display device according to the present embodiment, the band of each illumination light is narrowed by using a multi-chip color LED light source (pseudo-white light source). Note that FIG. 3A shows an example of the spectral characteristics of the phosphor-type white LED that has passed through the color filter twice, and FIG. 3B shows the spectral characteristics of the multi-chip color LED that has passed through the color filter twice. An example is shown. From FIGS. 3A and 3B, it can be confirmed that the wavelength band of each color is narrower in the multi-chip full-color LED than in the phosphor-type white LED. In the multi-chip full-color LED, three RGB LED chips are enclosed in one package. As an example of the specifications of the multi-chip full-color LED, there is a view angle of 116 deg and a brightness of 970 to 1940 mcd (simultaneous lighting).

1.3. Configuration with adhesion between interference fringes and color filter Next, the positional relationship between the color filter 4 and the interference fringe layer 2 will be described. Conventionally, in the case of a single-color reflective CGH, as shown in FIG. 4A, a high reflectance film 2 (Cr film or the like) in which interference fringes are formed on the back surface of the light receiving surface of the glass substrate 10 A low reflectance film 14 (CrO film or the like) that protects the glass substrate and the interference fringe layer is arranged. In order to attach the color filter 4 to the configuration shown in FIG. 4A, it is necessary to attach the color filter 4 to the front surface of the glass substrate 10 as shown in FIG. 4B. However, the gap generated between the color filter 4 and the reflectance film 2 causes an error particularly near the boundary of the RGB segment. For this reason as well, it has been conventionally considered that full-color reproduction of CGH by a color filter is difficult.

Based on the above, in the hologram display device according to the present embodiment, as shown in FIG. 4C, the Cr film (high reflectance film 2) on the back side of the glass substrate 10 which has not been used conventionally. The color filter 4 is closely attached to the surface. At this time, the protective film (low reflectance film) may be removed or the film thickness may be reduced.

1.4. Pixel block configuration in color filter Next, (color) filtering for each pixel block will be described. When the color filter 4 is attached to the interference fringe layer 2 on the high reflectance film (Cr film) surface, it is impossible to apply a one-color color filter to one pixel of the interference fringes. This is because the pixel pitch of the interference fringes is as fine as 0.8 to 1.0 μm, whereas the color filter cannot create a pattern on the order of microns. Therefore, as shown in FIG. 5, the (RGB) segment (4r, 4g, 4b) of the color filter is applied to each pixel block (2r, 2g, 2b) of the interference fringe 16.

1.5. Regarding the formation of interference fringes In the hologram display device according to the present embodiment, the interference fringes are formed on the metal film layer by lithography using a laser drawing device or an electron beam drawing device. FIG. 6 is a diagram showing an outline of a drawing method by lithography. A Cr film 8'and a resist layer 6 are laminated on the glass substrate 10 (see FIG. 6A). First, as shown in FIG. 6A, the resist layer 6 is exposed by laser irradiation or electron beam irradiation 12. Next, as shown in FIG. 6B, the resist layer 6 of the exposed portion is removed. Next, as shown in FIG. 6 (c), the exposed Cr film 8 is etched, and finally, as shown in FIG. 6 (d), the remaining resist layer 6 is removed. The layer for forming the interference fringes is not limited to the metal film 8 such as the Cr film 8', and the method for forming the interference fringes is not limited to lithography. Interference fringes may be formed on a member that can be processed to apply a fine pattern and has a high contrast of the applied pattern.

1.6. Method for manufacturing a hologram display device A method for manufacturing a hologram display device according to the present embodiment will be described. FIG. 1 is a diagram showing a method of manufacturing a hologram display device according to the first embodiment of the present invention. First, the design wavelength of each CGH (Computer-Generated Hologram) of RGB is optimized by using the (emission) spectrum data data (and the transmittance spectrum data of the color filter) (104) of each RGB LED as input data. The calculation to be converted is performed by a computer (step S02). At this time, after inputting data on the color of each RGB LED, for example, data on hue and brightness (106), an operation for optimizing the design wavelength of each RGB CGH is performed (step S02). preferable.

Next, using the optimized design wavelength data (see step S02) in each RGB CGH and the model data (102) of the three-dimensional scene as input data, first, CGH interference fringes are formed for each of RGB. , Computer-calculated (step S04, step S06, and step S08) to generate CGH interference fringe pattern data for each of RGB.

That is, in steps S02 to S08, the interference fringe data in the computer composite hologram for each primary color reference light is calculated to generate the CGH interference fringe pattern data for each of RGB (step S09). The calculation of the interference fringe data in the computer composite hologram for each primary color reference light may be different from steps S02 to S08 as long as the CGH interference fringe pattern data for each of RGB is appropriately generated.

In general, color filters are not highly accurate. Further, as described above, the resolution of the color filter is one digit or more lower than the physical resolution of the interference fringes on the high reflectance film (Cr film) surface (1 μm or less, 25,000 dpi or more). Based on these facts, the position error information (data) (108) of the color filter is input to the computer. Based on the color filter position error information (data) (108), the computer generates data for position correction of color filter patterns such as interference fringes by stripes and guard gaps (step S10). The "stripes" and "guard gaps" will be described later.

By inputting the calculated and generated CGH interference fringe pattern (see steps S04, S06, S08) data for each of the RGB and the data of the position correction of the interference fringe by the stripe and the guard gap, the computer has high reflection. Data after synthesis of the interference fringe pattern actually formed on the reflectance film (Cr film) is generated and output (step S12).

The above steps S02 to S12 are performed by the computer based on the input data.

Further, as shown in FIG. 6, the interference fringe layer 2 is formed on the metal high reflectance film (Cr film) 8 by the lithography apparatus (step S14). The high reflectance film (Cr film) 8 on which the interference fringe layer 2 is formed is bonded to the color filter 4 (see FIGS. 5 and 4).

As described above, a hologram display device (110) for full-color CGH is produced.

1.7. Configuration of the guard gap at the boundary of the interference fringes Next, the guard gap formed in the interference fringes will be described. In principle, if the color filter is accurately mounted on the surface of the high reflectance film (Cr film), full-color reproduction by the hologram display device is possible. However, in reality, it is impossible to bond the high reflectance film (Cr film) 8 on which the interference fringe layer 2 is formed and the color filter 4 without causing an error as shown in FIG. 7A. Yes, as shown in FIG. 7B, the positions of the interference fringe layer 2 and the color filter 4 are displaced. In FIG. 7B, the color filter 4 is slightly offset below the paper surface with respect to the interference fringe layer 2. When the positions of the interference fringe layer 2 and the color filter 4 are deviated in this way, chromatic aberration is caused by irradiating the error portion with illumination light having a wavelength different from that at the time of calculating the interference fringes (furthermore, at the time of recording). This will occur and the reproduced image will deteriorate.

For example, the illumination light indicated by the first arrow from the top of FIG. 7B is an illumination light having a wavelength of blue (B), and therefore must be reflected by interference fringes for blue (B). .. However, when the color filter 4 and the interference fringe layer 2 are offset and bonded as shown in FIG. 7 (b), the illumination light indicated by the arrow at the top of FIG. 7 (b) is red (R). It has been reflected by the interference fringes for. Chromatic aberration occurs here, which deteriorates the reproduced image. The same applies to the illumination light indicated by the second to sixth arrows from the top in FIG. 7B.

In order to deal with such deterioration of the reproduced image, in the present embodiment, as shown in FIG. 8B, a gap 18 is provided at the boundary of the interference fringe blocks of each color to give an allowance for an error. The gap 18 is hereinafter referred to as a guard gap (Guard Gap) (FIG. 8A is a diagram showing the interference fringe layer 2 without the guard gap). When the guard gap 18 is provided in the hologram display device shown in FIG. 7 (b) where chromatic aberration has occurred, interference fringes having a structure as shown in FIG. 9 (a) are formed. Since the interference fringes transmit illumination light having a wavelength different from that at the time of recording, which has been a cause of chromatic aberration, these illumination lights do not affect the reproduced light.

For example, the illumination light of the blue (B) wavelength indicated by the first arrow from the top of FIG. 9 (a) is the illumination indicated by the first arrow from the top of FIG. 7 (b) if there is no guard gap 18. It will be reflected by the interference fringes for red (R) like light. As shown in FIG. 9 (b), the illumination light having the blue (B) wavelength is transmitted to the glass substrate 10 because the guard gap 18 is provided here, and as a result, the blue (B) The illumination light of the wavelength does not cause chromatic aberration (it does not affect the reproduced light).

The configuration shown in FIG. 9A is used as a reflective hologram display device, and chromatic aberration is prevented from being generated by transmitting light in a boundary region (guard gap). On the other hand, the configuration shown in FIG. 9B is used as a transmissive hologram display device, and chromatic aberration is prevented from occurring by blocking (not transmitting) light in the boundary region (guard gap). .. For example, the illumination light of the blue (B) wavelength indicated by the first arrow from the top of FIG. 9 (b) passes through the interference fringes for red (R) without the guard gap 18, and then in FIG. 7. It passes through the color filter 4b for blue (B) like the illumination light indicated by the first arrow from the top of (b). As shown in FIG. 9B, the guard gap 18 is provided here, so that the illumination light having the blue (B) wavelength is blocked at the 10 end of the glass substrate. B) The illumination light of the wavelength does not cause chromatic aberration (it does not affect the reproduced light).

As described above, the reflective hologram display device and the transmissive hologram display device have different roles of the guard gap, and therefore need to be designed according to the application.

The inventor has also obtained knowledge that the reproduced image deteriorates when the guard gap width is too wide. As a result of repeating the simulation and the optical reproduction, the inventor has determined that the optimum value is 100 μm for the stripe width and 50 μm for the guard gap width (the stripe will be described later).

1.8. Configuration of a plurality of segments in a color filter Next, an example of configuration of a plurality of segments in a color filter will be described. As shown in FIG. 5, the (RGB) segment (4r, 4g, 4b) of the color filter 4 is applied to each pixel block (2r, 2g, 2b) of the interference fringe 16. That is, the color filter 4 according to the present embodiment is composed of a plurality of segments. Also, a segment adjacent to one segment is different from that (one) segment.

In the color filter 4 shown in FIGS. 2, 5, and 8, a plurality of segments form vertical stripes, but the configuration of the plurality of segments is not limited to this. For example, as shown in FIG. 10, a plurality of segments may form horizontal stripes. Since it is only necessary to consider the error in the vertical direction when forming the horizontal stripe, there is an advantage that the alignment of the segments is easy. Furthermore, horizontal parallax is important in stereoscopic images in the first place. In other words, since it is desirable that errors do not occur in horizontal parallax as much as possible, it can be said that in a hologram display device using a color filter, the reproduced image looks better when the stripes formed by the segments are horizontal rather than vertical. ..

Further, the composition of the plurality of segments of the color filter may be other than the vertical stripe and the horizontal stripe. Although not shown, it may constitute a delta.

[Second Embodiment]
2. 2. Other Configurations of Hologram Display Device The hologram display device according to the present invention is not limited to that of the first embodiment, and various changes and modifications can be incorporated. In particular, examples of other configurations of the reflective hologram display device will be described below. The other configurations of the following reflective hologram display device are basically the same as those of the reflective hologram display device according to the first embodiment, and the differences between the two will be mainly described.

In general, among full-color computer composite hologram display devices equipped with color filters, reflective ones often have a problem that the image is not so bright. The causes are that the manufacturing error of the color filter is not always small, and that light is transmitted at least twice through the color filter whose transmittance is not so high in the reflective hologram.

One of the solutions to the above problems is the use of phase modulation. 11 (b-1) and 11 (b-2) are schematic views of a reflective hologram display device using the concept of phase modulation. On the other hand, FIGS. 11 (a-1) and 11 (a-2) are schematic views of a reflective hologram display device using amplitude modulation of light.

FIG. 11A-1 is a diagram schematically showing opaque interference fringes in a reflective hologram display device using light amplitude modulation. In the reflective hologram display device using the amplitude modulation of light, it is relatively easy to manufacture the opaque interference fringes, but there is a problem that the light utilization efficiency is low and the image becomes dark. On the other hand, FIG. 11B-1 is a diagram schematically showing transparent interference fringes in a reflective hologram display device using phase modulation of light. In a reflective hologram display device that utilizes phase modulation of light, the efficiency of light utilization becomes high and the image becomes bright.

FIG. 11 (a-2) is a diagram schematically showing a cross section of a reflective hologram display device using amplitude modulation of light. FIG. 11 (b-2) is a diagram schematically showing a cross section of a reflective hologram display device using phase modulation of light. As described above, the reflective hologram display device shown in FIG. 11A-2 is configured by laminating a glass substrate 10, an interference fringe layer 2, and a color filter 4. Here, the interference fringe layer 2 is composed of a metal layer.

On the other hand, the reflective hologram display device shown in FIG. 11 (b-2) is configured by laminating a glass substrate 10, a metal film 32, a photoresist layer 22, and a color filter 4. Here, the photoresist layer 22 forms interference fringes. Since the transparent photoresist layer 22 forms interference fringes, the efficiency of light utilization becomes high and the image becomes bright.

[Third Embodiment]
The third embodiment utilizes a volumetric hologram generated by transfer. That is, the third embodiment utilizes the principle of volumetric holograms, in particular the principle of Denishuk-type volumetric holograms.

3.1. Advantages of Thin Holograms and Thick Holograms and Volumetric Holograms (Thick Holograms) With reference to FIGS. 12 and 13, the advantages of thin holograms and thick holograms and volumetric holograms will be described.

3.1.1. Thin Hologram First, FIG. 12A is a simplified diagram showing an imaging (recording) form of a conventional transmissive hologram. In the imaging (recording) mode of the transmissive hologram shown in FIG. 12A, the light emitted from the laser 52 is split in two directions by the beam splitter 54. One of the branched laser beams is applied to the object 64 (to be recorded) via the mirror 56 and the lens 60. The other of the branched laser beams is directly applied to the recording material 70 via the mirror 58, the lens 62a and the lens 62b.

The object light 68, which is the reflected light from the object 64, and the reference light 66, which is directly irradiated on the recording material 70, interfere with each other on the recording material, and the intensity distribution of the reference light 66 is recorded by the recording material as a hologram. .. At the time of reproduction, the recording material 70 is irradiated with the same reproduction illumination light as the reference light 66. At this time, when the recording material 70 is viewed from the side opposite to the reproduction illumination light, the object image is reproduced before passing through the recording material 70. Therefore, the hologram recorded by the photographing (recording) mode shown in FIG. 12A is a transmissive hologram.

Further, as in the photographing (recording) mode shown in FIG. 12A, since the reference light 66 and the object light 68 are irradiated from the same direction (same side) to the recording material 70, the interference fringes are the recording material. Generated on the surface of 70. Such holograms are commonly referred to as "thin holograms" as opposed to "thick holograms" which will be described later.

3.1.2. Thick hologram (volumetric hologram)
Next, FIG. 12B is a simplified diagram showing an imaging (recording) form of a conventional reflective hologram. In the imaging (recording) mode of the reflective hologram shown in FIG. 12B, the light emitted from the laser 52 is split in two directions by the beam splitter 54. One of the branched laser beams is applied to the object 64 (to be recorded) via the mirror 56 and the lens 60. The other of the branched laser beams is directly applied to the recording material 70 from the side opposite to the object 64 via the two mirrors (mirror 58, mirror 59), the lens 62a and the lens 62b.

The object light 68, which is the reflected light from the object 64, and the reference light 66, which is directly applied to the recording material 70 from the opposite side of the object 64, interfere with each other on the recording material, but the intensity distribution thereof is recorded. What is recorded by is a hologram. At the time of reproduction, the recording material 70 is irradiated with the same reproduction illumination light as the reference light 66. At this time, when the recording material 70 is viewed from the side of the reproduction illumination light, the object image is reproduced by the reflection of the reproduction illumination light. Therefore, the hologram recorded by the photographing (recording) mode shown in FIG. 12B is a reflective hologram.

Further, as in the photographing (recording) mode shown in FIG. 12B, the recording material 70 is irradiated from the opposite direction (opposite side) to the reference light 66 and the object light 68, so that the interference fringes are generated. Recording material 70 Three-dimensionally recorded in the depth direction. Such a hologram is generally referred to as a "thick hologram" as opposed to the above-mentioned "thin hologram", and is also further referred to as a "volumetric hologram".

3.1.3. Advantages of Volumetric Hologram FIG. 13 (a) is a schematic longitudinal sectional view of a thin hologram. In thin holograms, interference fringes are two-dimensionally generated on the surface of the recording material 70. On the other hand, FIG. 13B is a schematic vertical sectional view of a volumetric hologram (thick hologram). In the volume hologram, the interference fringes are generated three-dimensionally in the depth direction of the recording material 70. In this case, the interference fringes are recorded as a large number of layered structures substantially parallel to the hologram surface. It is known that volumetric holograms are superior in wavelength selectivity and angle selectivity to thin holograms because regenerated light is generated by multiple interference between fringes.

Then, assuming a "volumetric computer composite hologram" in which the volumetric hologram and the computer composite hologram (CGH) described above are combined, the following (1-a) to (2-b) and the like are obtained. There are many advantages.

(1) Advantages of computer composite hologram (CHG) itself (1-a) No real object is required to create the hologram. A hologram can be created only from a three-dimensional model as data.
(1-b) Data can be stored and transferred as digital data.

(2) Advantages of volumetric hologram (2-a) It is excellent in wavelength selectivity, and even if white reproduction illumination light is used, only the same wavelength as at the time of recording is selected and reproduced. That is, it can be reproduced with white reproduction illumination light.
(2-b) It has excellent angle selectivity and can be reproduced even if the light source of the reproduction illumination light is large.

By the way, depending on the usual method for creating a computer composite hologram (CHG), for example, a method using a printer or a method using a fine processing technique, an interference fringe is generated three-dimensionally in the depth direction of the recording material. Holograms cannot be produced. Therefore, in the third embodiment, the original CGH (computer composite hologram) (interference fringe) is transferred to the volumetric hologram to realize the “volumetric computer composite hologram” assumed above. Since the "volumetric computer synthetic hologram" according to the third embodiment is generated by transfer, mass production is facilitated.

3.1.4. Denishuk-type volumetric hologram Here, the Denishuk-type volumetric hologram will be described. FIG. 12 (c) is a simplified diagram showing an imaging (recording) form of a Denishuk-type volumetric hologram. In the imaging (recording) mode of the Denishuk-type volumetric hologram shown in FIG. 12 (c), the light emitted from the laser 52 and passing through the mirror 56 and the lens 60 passes through the recording material 70 and is transmitted (to be recorded) to the object 64. Is irradiated to. The light emitted from the laser 52 and passing through the mirror 56 and the lens 60 also functions as the reference light 66. Therefore, the object light 68 reflected from the object 64 and the reference light 66 interfere with each other, interference fringes are recorded on the recording material 70, and a Denishuk-type hologram is produced. In producing this Denishuk-type hologram, since the object light 68 is incident on the recording material 70 from the side opposite to the reference light 66, the Denishuk-type hologram becomes a volumetric hologram.

Denishuk holograms that capture (record) volumetric holograms are known to have advantages such as a very simple recording optical system, resistance to disturbances such as vibration, and easy imaging of large objects. .. Therefore, in the third embodiment, a hologram display device is manufactured by transferring the original CGH (computer synthetic hologram) (interference fringes) to a Denisuke type volumetric hologram.

3.2. Preparation by Transfer of Denishuk-type Volumetric Hologram The principle and schematic procedure of preparation of the Denishuk-type volumetric hologram according to the third embodiment by transfer will be described. FIG. 14 is a schematic view showing a state of reproduction of a metal film high-resolution original CGH used in the production by transfer of a Denishuk-type volumetric hologram according to a third embodiment. The high-resolution original CGH (interference fringe) of the metal film here is produced by laser lithography, has a high reflectance of the interference fringe itself, and enables highly efficient reproduction as a reflection type. ..

The metal film high-resolution original CGH (interference fringes) is formed on the surface of the chromium film 88. Further, the surface of the chromium film 88 is closely covered with the glass substrate 90. When the reproduction illumination light 82 is irradiated from the reproduction illumination light source 80 to the surfaces of the glass substrate 90 and the chromium film 88, the reproduction light 84 accompanied by the reproduction image 86 is emitted to the observer 94 on the side of the reproduction illumination light source 80. It will be generated (reproduced) and delivered.

Next, FIG. 15 is a schematic view showing the state of transfer of the metal film high-resolution original CGH to the recording material 105. In FIG. 15, the recording material 105 is attached to the glass substrate 90 that closely covers the surface of the chromium film 88 on which the original plate CGH (interference fringes) of the metal film high resolution is formed. Further, the pinhole position of the spatial filter 98 of the reproduction illumination light source 96 is set so as to coincide with the center position of the virtual reference optical spherical wave for creating the original CGH.

When the reproduction illumination light 82 is irradiated from the reproduction illumination light source 96 to the surface of the chromium film 88 on which the original CGH (interference fringes) are formed, the reproduction light 84 with the reproduction image 86 is generated as described in FIG. It is generated (reproduced). The regenerated light becomes the object light 103, and the regenerated illumination light 82 from the regenerated illumination light source 96 simultaneously becomes the reference light 101, and interference fringes are recorded on the recording material 105. This is a transfer of the metal film high resolution original CGH. At the same time, this is the same as recording the object light 68 light wave of the object 64 placed on the back surface of the recording material 70 in the imaging (recording) form of the Denishuk type volumetric hologram shown in FIG. 12 (c). Is. Therefore, what is produced by transfer is a volumetric hologram.

As the recording material 105 shown in FIG. 15, a silver salt film, a photopolymer, or the like is used. In FIG. 15, the recording material 105 is attached to a glass substrate 90 that closely covers the surface of the chromium film 88 on which the original plate CGH (interference fringes) of the metal film high resolution is formed, but the recording material 105 is made of metal. The film may be attached to the surface of the chromium film 88 on which the high-resolution original CGH (interference fringes) is formed.

As described above, the Denishuk-type volumetric hologram produced by transfer utilizes the fact that the metal film high-resolution original CGH produced by laser lithography enables highly efficient reproduction as a reflective hologram. There is. Since it can be transferred to a volumetric hologram by one step of one exposure, the recording optical system is simple, the resistance to vibration is extremely strong, and a hologram having excellent wavelength selectivity and angle selectivity can be generated. Become.

Therefore, the Denishuk-type volumetric hologram produced by transfer can be a transfer CGH that can be reproduced by various light sources such as a white light source and a large light source. Further, even if a white reproduction light source is used, only the wavelength of the light (regeneration illumination light, reproduction light, and reference light) used at the time of transfer is reproduced. From this, as will be described below, the Denishuk-type volumetric hologram produced by transfer can be developed in a full-color high-resolution computer composite hologram display device.

3.3. Full-colorization of Denishuk-type volumetric hologram produced by transfer Using FIGS. 16, 17, 18 and 19, a full-color high-resolution computer composite hologram display device for Denishuk-type volumetric hologram produced by transfer. The development to is explained.

3.3.1. Method for Fabricating Full-Color High-Resolution Computer Synthetic Hologram Display Device of the First Form FIG. 16 shows a full-color high-resolution computer synthetic hologram display in which the Denishuk-type volumetric hologram produced by transfer of the first embodiment is full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of the apparatus. First, the original CGH / R110r, the original CGH / G110g, and the original CGH / B110b each represent CGH interference fringes of each color of R (red), G (green), and B (blue). First, the original CGH / R110r is transferred to the volumetric hologram R (red) 112r by using the R (red) laser as the regenerative illumination light (in FIGS. 14 and 15) and the reference light (recording after recording). Create material R (red)). Next, 110 g of the original CGH / R is transferred to 112 g of the volumetric hologram G (green) by using the G (green) laser as the reproduction illumination light and the reference light (to create the recording material G (green) after recording). ). Further, the original CGH / R110b is transferred to the volumetric hologram B (blue) 112b by using the B (blue) laser as the reproduction illumination light and the reference light (creating the recording material B (blue) after recording). ..

Finally, the recording materials R, G, and B after recording are superposed to produce a full-color high-resolution computer composite hologram display device. In the production method according to the first embodiment, three original CGHs and three transfer holograms are used, and the number of transfer shots is three. A feature of this manufacturing method is that it is easy to align. Of course, the production order of the recording materials R, G, and B produced by the transfer may be different from that shown in FIG. The order of superposition of the recording materials R, G, and B after recording may also be different from that shown in FIG.

3.3.2. Method for Fabricating Full-Color High-Resolution Computer Synthetic Hologram Display Device of the Second Form FIG. 17 shows a full-color high-resolution computer synthetic hologram display in which the Denishuk-type volumetric hologram produced by transfer of the second embodiment is full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of the apparatus. First, similarly to FIG. 16, the original CGH / R110r, the original CGH / G110g, and the original CGH / B110b each represent CGH interference fringes of each color of R (red), G (green), and B (blue). There is.

First, the original CGH / R110r is transferred to the volumetric hologram R (red) 112r by using the R (red) laser as the regenerative illumination light (in FIGS. 14 and 15) and the reference light (recording after recording). Create material R (red)).

Next, the volume hologram R (red) 112r is superposed on the recording material R (red), and the original CGH / G 110 g is transferred using the G (green) laser as the reproduction illumination light and the reference light to transfer the volume hologram RG (red). , Green) 112 rg of recording material RG (red, green) is created.

Further, the volume hologram RG (red, green) is superimposed on the recording material RG (red, green) of 112 rg, and the original CGH / B110b is transferred using the B (blue) laser as the reproduction illumination light and the reference light to transfer the volume hologram. RGB (red, green, blue) 112 rgb recording material RGB (red, green, blue) is created. In the production method according to the second embodiment, three original CGHs and one transfer hologram are used, and the number of transfer shots is three. The features of this manufacturing method are that multiple exposures are performed and that alignment is difficult. In the production method according to the second embodiment, the order of transfer by the R, G, and B lasers may be different from that shown in FIG.

3.3.3. Method for Fabricating a Synthetic Hologram Display Device for a Full-Color High-Resolution Calculator of the Third Form FIG. It is a figure which shows the manufacturing method and manufacturing apparatus of a synthetic hologram display apparatus. The recording material 120 of the original CGH and the color filter 118 shown in FIG. 18A are metal films on which the interference fringe layer 2 (shown in FIG. 2) according to the first embodiment is formed. And, it corresponds to the color filter 4. Therefore, the recording material 120 of the original CGH includes interference fringe blocks of each color of RGB and a guard gap between the interference fringe blocks (see FIG. 8B). The color filter 118 includes (RGB) segments of the color filter corresponding to the interference fringe block (see FIG. 2).

First, the original CGH is converted into a volumetric hologram R by using the recording material 120 of the original CGH and the color filter 118 and using the R (red) laser as the regenerative illumination light (in FIGS. 14 and 15) and the reference light. Transfer to (red) 122r (create recording material 124 (red) after recording). At this time, the red block portion of the original CGH is transferred.

The approximate positional relationship between the recording material 120 of the original CGH, the color filter 118, the recording material 124 after recording, and the laser for transfer is as shown in FIG. 18 (b). The same applies to the following procedure.

Next, using the recording material 120 of the original CGH and the color filter 118, the G (green) laser is used as the reproduction illumination light and the reference light, so that the recording material 124 of the volume hologram R (red) 122r is superimposed. The original CGH is transferred to prepare a recording material 124 (red, green) of 122 rg of volume hologram RG (red, green). At this time, the green block portion of the original CGH will be transferred.

Further, by using the recording material 120 of the original CGH and the color filter 118 and using the B (blue) laser as the reproduction illumination light and the reference light, the recording material 124 of the volume hologram RG (red, green) 122 rg is superimposed. , The original CGH is transferred to create a recording material 124 (red, green, blue) of volumetric hologram RGB (red, green, blue) 122 rgb. At this time, the blue block portion of the original CGH is transferred. In the production method according to the third embodiment, one original CGH, one color filter, and one transfer hologram are used, and the number of transfer shots is three. The features of this manufacturing method are that multiple exposure is performed, alignment is easy, and a hologram having a higher quality than the original plate is obtained. Also, the color filters are reusable. In the production method according to the third embodiment, the order of transfer by the R, G, and B lasers may be different from that shown in FIG. 18A.

3.3.4. Method for Fabricating Synthetic Hologram Display Device for Full-Color High-Resolution Calculator of Fourth Mode FIG. 19 (a) shows a full-color high-resolution calculator in which the Denishuk-type volumetric hologram produced by transfer of the fourth embodiment is full-color. It is a figure which shows the manufacturing method and manufacturing apparatus of a synthetic hologram display apparatus. Similar to the manufacturing method according to the third embodiment, the recording material 120 of the original CGH and the color filter 118 shown in FIG. 19A each relate to the first embodiment (shown in FIG. 2). ) Corresponds to the metal film on which the interference fringe layer 2 is formed and the color filter 4. Therefore, the recording material 120 of the original CGH includes interference fringe blocks of each color of RGB and a guard gap between the interference fringe blocks (see FIG. 8B). The color filter 118 includes (RGB) segments of the color filter corresponding to the interference fringe block (see FIG. 2).

In the manufacturing method according to the fourth embodiment, the RGB laser (mixed with R (red) laser, G (green) laser, and B (blue) laser) using the recording material 120 and the color filter 118 of the original CGH. Is transferred to the volumetric hologram RGB (red, green, blue) 122 rgb (recording material 124 (red, green, green) after recording) by using the reproduction illumination light (in FIGS. 14 and 15) and the reference light. , Blue) to create). In the manufacturing method according to the fourth aspect, RGB three-wavelength lasers are coaxially superimposed. Further, in the production method according to the fourth embodiment, all of the red block portion, the green block portion, and the blue block portion of the original CGH are transferred.

The approximate positional relationship between the recording material 120 of the original CGH, the color filter 118, the recording material 124 after recording, and the laser for transfer is as shown in FIG. 19 (b). In the production method according to the fourth aspect, one original CGH, one color filter, and one transfer hologram are used, and the number of transfer shots is one. The features of this manufacturing method are that multiple exposure is performed, alignment is easy, and a hologram having a higher quality than the original plate is obtained. Also, the color filters are reusable. Further, since the number of transfer shots is one, the production method according to the fourth embodiment is for more mass production.

2 ... Interference fringe layer, 4 ... Color filter, 6 ... Resist layer, 8 ... Metal film, 8'... Cr film, 10 ... Glass substrate, 16 ... Interference fringe , 18 ... guard gap, 22 ... photoresist layer, 32 ... metal film, 64 ... object, 70 ... recording material, 94 ... observer, 82 ... regenerated illumination light , 84 ... Regenerated light, 101 ... Reference light, 103 ... Object light.

Claims (10)

A metal film with interference fringes and
A color filter composed of a combination of color filter segments of multiple colors,
Includes the metal film and a reference light source that illuminates the color filter.
The interference fringes of the metal film are formed corresponding to the individual color filter segments constituting the color filter.
In the interference fringes of the metal film corresponding to the portions where the color filter segments of different colors are adjacent to each other, a guard gap is provided to guard the illuminated reference light.
The guard gap is a gap that gives an allowance for an error portion between the color filter segment and the interference fringe block at the boundary between the interference fringe blocks of each color.
Hologram display device. The hologram display device according to claim 1, wherein the interference fringes are formed based on a computer composite hologram. The hologram display device according to claim 1, wherein each color filter segment corresponds to a plurality of pixels in an interference fringe. It is a reflective type and the guard gap transmits the reference light.
The hologram display device according to claim 1. It is a transmissive type, and the guard gap blocks the reference light.
The hologram display device according to claim 1. The hologram display device according to claim 1, wherein the reference light source is a multi-chip color LED light source. The hologram display device according to claim 1, wherein the metal film and the color filter are formed in close contact with each other. The hologram display device according to claim 1, wherein a plurality of color filter segments form a color filter pattern. Steps to calculate the interference fringe data in a given computer composite hologram,
Based on the color filter creation accuracy, the color filter resolution, and the color filter position error information based on the interference fringe resolution, the color filter pattern position correction data and the interference fringe position correction data due to the guard gap are obtained. The calculation step, wherein the guard gap is a gap that gives an allowance for an error portion between the color filter segment and the interference fringe block at the boundary between the interference fringe blocks of each color.
A step of generating composite data of an interference fringe pattern based on the position correction data of the color filter pattern and the position correction data of the interference fringes due to the guard gap, and
Steps to form interference fringes on the film based on the composite data of the interference fringe pattern,
With the step of bonding the film with the interference fringes and the color filter
including
A method of manufacturing a hologram display device. Design of computer composite hologram for primary color reference light emitted by each primary color LED constituting multi-chip color LED based on emission spectrum data of each primary color LED constituting multi-chip color LED and transmission spectrum data of color filter Steps to optimize the wavelength and
A step of calculating the interference fringe data in the computer composite hologram for each primary color reference light based on the model data of the three-dimensional scene and the data of the design wavelength in the optimized computer hologram.
Based on the color filter creation accuracy, the color filter resolution, and the color filter position error information based on the interference fringe resolution, the color filter pattern position correction data and the interference fringe position correction data due to the guard gap are obtained. The calculation step, wherein the guard gap is a gap that gives an allowance for an error portion between the color filter segment and the interference fringe block at the boundary between the interference fringe blocks of each color.
A step of generating the composite data of the interference fringe pattern based on the interference fringe data in the computer composite hologram for each primary color reference light, the position correction data of the color filter pattern, and the position correction data of the interference fringe by the guard gap.
Steps to form interference fringes on the film based on the composite data of the interference fringe pattern,
With the step of bonding the film with the interference fringes and the color filter
including
A method of manufacturing a hologram display device.