JP3405465B2 - Manufacturing method of color hologram - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a color hologram.
In particular, the pseudo color holograph
System, and add color information to holograms
It relates to a manufacturing method. 2. Description of the Related Art Recently, Lippmann holograms or volume type
A hologram called a hologram is displayed as a color image,
It has been considered to be used as an anti-formation medium. This
Ip holograms have interference fringes in the thickness direction of the optical recording material.
It is to be recorded. Conventionally, for colorizing a volume hologram,
Shot with multiple exposures using lasers of three different wavelengths
Or two or more holograms with different reproduction colors
There is a method of laminating gram, but these methods are
Process is complicated and lacks reproducibility of reproduced colors
There is a problem. A volume hologram has a single reconstructed wave.
A hologram with a length that can be easily duplicated
And cannot record additional information such as numbers
Was. [0005] As described above, the conventional
In volume holograms, colorization is not easy,
Also, prevent duplication and forgery, and add additional information
It was difficult. The present invention has been made in view of such circumstances.
The purpose of the volume hologram is to
Reproduce pseudo color holograms in continuous tones in a simple way
Colors of different colors that can be easily produced and difficult to duplicate
-By providing a manufacturing method that can add information
is there. [0007] The present invention for achieving the above object.
Ming's color hologram method uses light in the thickness direction of the film.
A hologram in which the interference fringes are recorded.
Is partially shortened to have a spatial distribution
And the reproduction wavelength from that part varies depending on the interval between the interference fringes.
Interference in the production method of color holograms
At least one of heat and pressure is applied to the hologram on which the fringes are recorded.
Is applied with a partial distribution with a spatial distribution.
The interval between the interference fringes in that part is shrunk according to the distribution.
It is a method characterized by making it. According to the present invention, a hologram on which interference fringes are recorded is provided.
The ram has a spatial distribution of at least one of heat and pressure.
By applying partially, the interference fringes in that part
The distance between the lines is contracted according to the distribution, so
Spatial spacing of the interference fringes to correspond to the
Pseudo color hologram in a simple way by distributing
Rams can be manufactured with continuous color tones with good reproducibility. Also,
Numbers, letters, and patterns added from the outline of the part where the raw color changes
Turns can be recognized. In addition, the spacing of the interference fringes is continuous
The hologram reproduction color changes continuously
The resulting hologram has excellent design. Also like this
If you try to duplicate a hologram with extra information added,
The postscript portion is not copied, and that portion becomes a blank portion. I
Therefore, replicating counterfeit products from original products
Becomes impossible. Also, the hologram information and postscript information are the same
Of additional interference information.
If you try to remove or add,
, The history of tampering becomes clear, and tampering and forgery
Can be prevented. DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a method for producing a color hologram of the present invention will be described.
Will be described with reference to the drawings. Volume type
The hologram is on one side of the recording material, such as a photopolymer.
When the object light enters from the other side and the reference light enters from the other side,
Transmittance distribution or refractive index distribution at an interval d in the thickness direction of the recording material
Are recorded, and the interval d between the interference fringes is the wavelength
Is λ, the refractive index of the recording material is n, and the distance between the object light and the reference light is
Assuming that the angle is θ, d = λ / (2n · sin θ / 2) (1). Volumetric hologram recorded in this way
When white light is incident on the ram, only light of wavelength λ is diffracted.
The recorded information is reproduced. Between the interference fringes of such a volume hologram
The distance d can often be expanded or contracted after recording
Are known. For example, in the case of a silver halide photographic film, D-
Swelling after recording with sorbitol allows for
d spreads, and conversely, swells the unexposed silver halide photographic film.
After that, exposure recording is performed and the swelling agent is removed.
The gap d shrinks. When such expansion and contraction processing is performed, generally,
Changes the slope of the interference fringes. As described above, the interval between interference fringes during recording changes.
Then, the interval between the interference fringes at the time of reproduction differs from d in Expression (1).
Value d ', the reproduced wavelength λ' is also the wavelength at the time of recording.
If the distance changes from λ and the interval widens, shift to the longer wavelength side.
If it shrinks, it shifts to the shorter wavelength side. Incidentally, the interval of such interference fringes is recorded.
When it changes continuously from the time interval, the reproduction wavelength also changes continuously.
Shift to the long wavelength side or short wavelength side. See FIG. 1 for this point.
To explain, the hologram 2 on the substrate 1
The distance between the interference fringes 6 is changed from left to right in the figure
If it is formed to increase continuously,
From the area (1) where the interval between the interference fringes 6 is small,
For example, as shown in (1), the wavelength B (500 nm)
The light of the spectral distribution with the center is diffracted and looks blue,
From the area (3) where the interval between the interference fringes 6 at the right end is wide,
As shown in rough (3), for example, wavelength R (600 nm)
Light with a spectral distribution centered on
Also, from the area (2) where the interval between the interference fringes 6 is intermediate,
As shown in the graph (2) of the figure, the intermediate wavelength G
(550 nm) with a spectral distribution centered at diffraction
It looks green. Thus, the interval between the interference fringes 6 is empty.
When the wavelength changes continuously, the reproduction wavelength (color) is also spatial
Changes continuously. The graphs (1) to (1) in FIG.
In (3), λ on the horizontal axis represents wavelength, and r on the vertical axis represents reflectance.
(Diffractive index). Further, the interval between the interference fringes is continuously changed from the interval at the time of recording.
Even if they change not continuously but binaryly,
When the area ratio changes continuously spatially, the reproduction color becomes continuous
Changes to This will be described with reference to FIG. In the figure
The intervals d and d 'of interference fringes in the hologram 2 are schematically shown.
Like this, the interval of the interference fringes is expanded from d to d '
And the interval d 'between the interference fringes in the halftone dot portion is wide, for example, red
(R) light with a long wavelength is diffracted, and
The interval d between the interference fringes is narrow, for example, blue (B) light having a short wavelength.
Is diffracted. Therefore, reduce the size of the halftone dots,
By changing the ratio of halftone dots to the area per unit
And the additive mixture of blue and red produces a color between blue and red.
Can be done. Halftone percentage in hologram 2 is 0%
If it changes continuously from to 100%, the hologram
2 (100% dot area (1), 50% area)
(2), reflectance from 0% region (3) according to wavelength λ
(Diffractive index) r is in a region (1) where the dot ratio is 100%.
Means that the reproduction color spectrum distribution is as shown in graph (1).
In the area (3) which looks red and has a dot percentage of 0%,
The reproduction color spectrum distribution is as shown in graph (3),
It looks like a color and is in the area (2) where the halftone dot ratio is 50%.
Therefore, the reproduction color spectrum distribution is as shown in graph (2).
And the ratio of blue B and red R is green due to the principle of additive color mixing.
The color G becomes visible. In the present invention, the above phenomenon is used.
Color hologram recorded on the film
-Write a pattern. Below, reference examples and implementation
This will be described based on an example. Here, a volume hologram
In some cases, some information may be recorded,
Uniform phase volume diffractometer with no information recorded
It may be a hologram recording a child. FIG. 3 shows a portion corresponding to information to be recorded.
One reference example to increase the spacing between interference fringes of a volume hologram
FIG. 4 is a diagram for explaining a schematic process and operation of FIG.
(A) As shown in FIG.
Using the hologram recording material 3 coated with the agent layer 2
Object light 4 is incident on one surface and reference light 5 is incident on the other surface
The interference fringes 6 are recorded. After development
As shown in (b), the numbers, characters,
Lipman hologra to represent variable information such as turns
Swelling ink consisting of D-sorbitol, etc.
And print 7. This printing requires that the amount of swelling ink
Therefore, the difference is made so that the dot ratio is different. The expansion
The application of the lubricating ink is not limited to printing, and transfer may be used.
No. The applied swelling ink is placed in the volume hologram 2.
Penetrate and expand the layer according to the amount of printing ink
Therefore, as shown in the partially enlarged view of FIG.
The interval between the interference fringes 6 is widened, and the inclination changes. this
Volume holograph with swollen interference fringes 6 of 7 copies
When the white reproduction light 8 is incident on the system 2, as shown in FIG.
In other words, from the other than the 7 copies,
The recorded information is reproduced, and from the 7 copies of printing,
Different wavelengths λ ', λ ", λ"", longer than the recording wavelength λ
The hologram recording information is reproduced in the direction shown in FIG. Accordingly
Number and text added from the outline of the part where the reproduction wavelength differs.
Characters, patterns, etc. can be recognized. The interval between the interference fringes 6 is
It changes continuously from the postscript section to the surrounding area depending on the location.
As a result, the reproduction color of the hologram changes continuously,
Become an excellent hologram. Then, such information is temporarily added.
The wavelength λ is obtained by superimposing another recording material on the Lippmann hologram.
If you try to duplicate using the light source of
Is not duplicated because diffraction does not occur at the wavelength of
It will be a piercing part. Therefore, counterfeit products from original products
Would be impossible to duplicate. Also, hologram information
And additional information are formed from the same continuous interference fringes
So if you try to delete or add additional information,
Tampering history is clarified because of missing part in ram information
Falsification and forgery can be prevented. As described above, in the case of a silver salt photographic emulsion, D-
Printing a predetermined amount using a swelling liquid such as sorbitol
The distance between the interference fringes in the predetermined part of the volume hologram
Although it can be expanded, the weight
When using chromate gelatin, the
Can be applied. Also, it is used as a hologram recording material.
Solvent, plasticizer, monomer
Or print a predetermined amount on the required part with oligomer and
The interference fringes can be selectively swollen by a predetermined amount. Further, using a photosensitive swelling film,
Color hologram can be formed
You. Hereinafter, the details will be described. That is, photopoly
As with the monomer, the monomer or
Photosensitive swelling film made by mixing ligomer, photoinitiator, etc.
Recording with interference fringes such as photopolymer
Before or after adhesion of the swelling film to the material
Then, the swelling film is irradiated with light having a predetermined light quantity distribution.
The monomer or oligomer contained in the swelled film
Is polymerized at a predetermined ratio in accordance with the amount of irradiation light for each position.
Activate to reduce the amount of remaining active monomer or oligomer
And adjust the adjusted amount in the recording material on which interference fringes have been recorded.
Swelling by diffusing into
Predetermined reproduction wavelength by precisely adjusting any predetermined amount at each position
To adjust the color pattern on the hologram.
It is a method to achieve. After swelling by such a method, interference
By irradiating or heating the stripe-recorded recording material,
Diffused monomer or oligomer can be fixed in interference fringes
As a result, holograms with excellent storage stability of reproduced colors can be obtained.
It is. Moreover, the film-shaped swelling material is laminated onto the hologram.
Just irradiate and irradiate with the specified light to achieve stable and accurate
Since swelling is obtained, this method is excellent in workability and reproducibility.
You. The above-mentioned colorization method will be described with reference to the drawings.
I will explain a little more in detail. Figure 4 shows the swelling fill
After irradiating the recording medium with the recording material, light irradiation
Deactivate the swelling agent (monomer, oligomer) contained
FIG. 5 shows the state before the swelling film is adhered to the recording material.
Irradiates light to make the swelling agent contained in the swelling film inert
FIG. 5 is a diagram for explaining the principle of the
In the case of FIG.
3 illuminate object light 4 and reference light 5 from both sides and interfere
When the stripe 6 is recorded, a volume-type photo as shown in FIG.
Program 2 is obtained. Next, as shown in FIG.
A monomer or oligomer in the binder polymer,
A swelling film 10 formed by mixing a photoinitiator and the like is adhered to the film,
Of the permeable monomer or oligomer in the swelling film 10
Before or simultaneously with heating to increase the degree of diffusion, FIG.
1) to (d3), the hologram 2 or the swollen
Light irradiation 11 is performed from the film 10 side. This light irradiation 11
From the active permeable monomer in the swelling film 11 or
Some or all of the oligomers are allocated according to the amount of light irradiation 11.
Polymerized only when it becomes inert and has no permeability (diffusion)
Become. Therefore, in FIG.
In some cases, the active permeable monomer in the swelling film 10
Or oligomers are almost eliminated, and even if heated
It hardly penetrates into the ram 2. So, for example,
In FIG. 3A, a volume hologram 2 is formed at a blue wavelength.
Assuming that the hologram has passed through the swelling process shown in FIG.
Gram 2 hardly swells, diffracts blue light and reproduces
I do. On the other hand, FIG.
In the case of 2), the active osmotic module in the swelling film 11 is used.
About half of the nomer or oligomer becomes inactive and heats
Then, the other half of the permeable monomer or oligomer
Penetrates into the hologram 2 and swells moderately. So
Therefore, the hologram 2 having passed through the swelling process shown in FIG.
Diffracts and reproduces green light longer than the blue wavelength.
Furthermore, in the case of FIG.
Active permeable monomer or oligomer in wet film 10
Remains as it is and when heated, most permeable
Mers or oligomers penetrate into hologram 4 to maximize
Swell. Therefore, the swelling process shown in FIG.
Hologram 2 diffracts red light longer than the green wavelength
And play. In this way, the swelling closely adhered to the hologram 2
To adjust the amount of light 11 that irradiates the moisture film 10
Thus, the reproduction color can be arbitrarily controlled between red and blue. In the case of FIG. 5, FIG.
In (b), similarly to FIGS. 4 (a) and (b),
The volume hologram 2 is obtained. On the other hand, FIG.
As shown in (c3), a monomer is contained in the binder polymer.
Or a swelling mixture obtained by mixing oligomers, photoinitiators, etc.
A room 10 is prepared, and a predetermined amount of light irradiation 11 is performed on the room 10
And active immersion therein by a ratio corresponding to the amount of light irradiation 11.
Part or all of the permeable monomer or oligomer becomes inert
And the permeability (diffusion) is lost. The light irradiation 11 already
Mino swelling film 10 is shown in FIGS.
As shown in FIG.
When heated, the hologram 2 expands according to the amount of light irradiation 11.
Light 11 irradiating the swelling film 10 because the degree of moisture changes
Similarly, by adjusting the amount of reproduction, the reproduction color can be changed from red to blue.
Can be arbitrarily controlled between. By the way, the swelling film 10 is as described above.
So that the monomer or oligomer in the binder polymer
And a hologram made by mixing
It is the same as a photopolymer for recording. Accordingly
Hologram recording photo without special preparation
Polymer can be used as the swelling film 10
You. Now, as described above, the swelling film 10
The reproduction color of the hologram 2 is changed according to the amount of light to be irradiated.
Spatial distribution in the intensity of light irradiation 11
The spatial distribution of reproduced colors (wavelengths)
Can be provided. For that purpose, FIG. 4 (d1)
(D3) or (c1) to (c3) in FIG.
Radiation 11 is described by, for example, a transmittance distribution as shown in FIG.
A mask having a patterned pattern or a net as shown in FIG.
Via a halftone mask having an image drawn by a point distribution
By doing so, the principle explained in FIG. 1 or FIG.
A color image on part or all of the volume hologram 2
Can be added. Hologram 2 before appending is blue
Reproduced uniform phase volume type diffraction grating recorded
When the mask of FIG. 6 is used,
The transmittance of the mask is 100%, and the transmittance of the mask in the portion b is 0.
%, And the transmittance of the mask in the portion c is 50%,
Blue, red, and green respectively at the corresponding positions on the hologram 2
Color can be colored and therefore pseudo
Typical color patterns can be added. Similarly,
In the case of using the mask of FIG.
0%, halftone percentage of part b is 0%, halftone percentage of part c is 50%
, Each at the corresponding position of the hologram 2
Can be red, blue, green coloring,
A pseudo color pattern can be added. Next, the interference fringes in the portion corresponding to the additional information
FIG. 8 shows a schematic process and operation of the embodiment of the present invention for reducing the interval.
This will be described with reference to FIG. As shown in FIG.
Hologram made by applying photopolymer 2 to the surface of plate 1
The object light 4 and the reference light 5 are caused to interfere with each other by using the
And the interference fringes 6 are recorded. Recorded volume hologram 2
In addition, as shown in FIG.
The stamp 9 is heated and pressed. The height of the inscription 9
Or different halftone dot ratios based on the color distribution
It is constituted so that it may become. Then, the interference fringe 6 at the engraved part is
As shown in the partially enlarged view of FIG.
In the meantime, the interval between the interference fringes 6 at the marking position is reduced, and the inclination is also changed.
Become Thus, the volume of contracted interference fringes 6 at the engraved part
When white reproduction light 8 is incident on the mold hologram 2, FIG.
As shown in (c), the recording wavelength λ
The hologram recording information is reproduced in color, and shrinks from the engraved part
Wavelengths λ ′, λ ″, λ ″ ″ shorter than the recording wavelength λ according to the amount.
The hologram recorded information is reproduced in different directions in.
Therefore, similar to the case of FIG.
Numbers, characters, patterns, etc. added from the outline of
The interval between the interference fringes 6 depends on the location and
Since it changes continuously from the part to the periphery, it has excellent design
Program. Then, falsification and forgery can be prevented. What
When the interval between interference fringes changes only by mechanical pressure
Does not necessarily require heating. As another method for reducing the interval between the interference fringes,
Before recording the fringes, swelling agents, other solvents, plasticizers or
Swell the entire hologram recording material using a nomer
After that, interference fringes are recorded on the recording material, and after recording,
Washing extraction using a solvent such as a swelling agent partially from the additional information part
The distance between the interference fringes can be reduced.
Wear. Also in this case, the amount of swelling agent etc. to be washed and extracted for each location
By controlling the color, the color differs from place to place and the reproduction wavelength
Can recognize the added information from the outline of the part with different
In addition, a hologram with excellent design
Tampering and forgery can be prevented. Further, the interval between the above interference fringes is partially widened.
The shrinking method and the shrinking method may be used at the same time. Hereinafter, when a photosensitive swelling film is used,
A specific example will be described. Example 1 The following components were prepared. Binder polymer: Vinac B-100 (polyvinyl acetate) 66.00 wt% Monomer (acrylic): Photomer 4039 (phenol ethoxylate monoacrylate) 17.00 wt% Sartomer 349 (ethoxylated bisphenol-A diacrylate) 3.00 wt% Plasticizer: 4G7 (tetraethylene glycol diheptanoate) 10.22 wt% Photoinitiator: O-chloro HABI (1,1'-biimidazole, 2.2'-bis [O-chlorophenyl] -4,4 ' , 5,5'-tetraphenyl) 3.70 wt% Sensitizer: JAW (cyclopentanone, 2,5-bis [(2,3,6,7-tetrahydro-1H, 5H-benzo [i, j ] Quinolidine-1-yl) methylene]-) 0.08 wt% or more of the composition is mixed with 97 wt% of dichloromethane, 3 wt%
In 2-propanol (22 wt% total solute)
Produced a film in the following manner. Complete coating solution without sensitizer
Stir until dissolved, and add ingredients to solvent while mixing
did. The sensitizer was then added. This step and the next
The process of applying the mixed solution to the rum is performed under red light.
Was. The solution (sensitizer) thus obtained was added to 5
0 μm thick polyethylene terephthalate (PET)
150μm deep gravure on transparent film substrate
Coated with a coater. After coating, dry
25μm thick polyethylene on the film
Laminate a transparent film of
A polymer / photosensitive swelling film was obtained. The high blue-sensitivity file obtained as described above
Argon ion laser 51
As shown in FIG. 4 (a), a blue light having a wavelength of 4 nm
The body light 4 and the reference light 5 are applied, and a volume-type hologram of blue reproduction color is applied.
Gram of interference fringes, and then irradiated with 50 mJ of ultraviolet light
Therefore, the monomer in the recording material is fixed and the volume type photo paper is fixed.
Program was obtained. Thereafter, the photosensitivity obtained as described above is obtained.
Laminate the swollen film on the volume hologram
Was. 8. Measured at 514 nm as an irradiation light source;
0mW / cm ^Two Using a halogen lamp of
The exposure amount was changed by adjusting the irradiation time as described above. [0038] Then, in a circulating oven at 120 ° C for 1 hour
To remove the permeable monomer in the photosensitive swelling film.
By migrating into the gram interference fringes.
The interference fringes were swollen to increase the interval. Thereafter, 100 mJ of ultraviolet light is applied to cause interference.
After fixing the monomer in the stripe, the irradiation time
According to (exposure amount), as shown in FIG.
Everything from blue to red around 500nm ~ 600nm
The diffraction wavelength and the reproduction color of can be obtained. Example 2 Blue-sensitive photopolymer film obtained according to Example 1
Blue of 514nm wavelength of argon ion laser
By the light, the object light 4 and the reference light 5 as shown in FIG.
To describe a volume phase diffraction grating consisting of uniform interference fringes.
After recording, this recording material was irradiated with 50 mJ of ultraviolet light.
The monomers in the mixture were fixed to obtain a volume phase diffraction grating. Thereafter, the photosensitive swelling film obtained in Example 1 was obtained.
The film was laminated on the volume phase diffraction grating. So
As shown in FIG.
The light source of Example 1
And irradiate the light for 1 minute.
Migrating Nomers into Interference Fringes of a Diffraction Grating
I widened the interval. After that, 100 mJ of ultraviolet light was applied to cause interference.
When the monomers in the stripes are fixed,
In this case, the reproduced color spectrum is as shown in the graph (1) of FIG.
It looks like a halo and looks blue, and in FIG.
It looks like graph (3) and looks red, and also, FIG.
Is green as shown in graph (2) in FIG.
Uniform volume phase diffractometer that diffracts blue wavelengths
A color image could be formed on the child. Example 3 Volume phase diffraction consisting of uniform interference fringes in the same manner as in Example 2.
A lattice was obtained. Thereafter, the photosensitive swelling film obtained in Example 1 was obtained.
The film is laminated on the volume phase diffraction grating,
Above is a photo of a pattern whose dot percentage changes continuously as shown in Fig. 7.
The mask is adhered to the swelling film side, and the light source of Example 1 is used.
Irradiate light for 1 minute, and
Migration into the interference fringes of the diffraction grating
The spacing was widened. After that, 100 mJ of ultraviolet light was applied to cause interference.
When the monomers in the stripes were fixed,
In this case, the reproduced color spectrum is as shown in the graph (1) of FIG.
It looks like a roar and looks red.
The color spectrum becomes blue as shown in graph (3) of FIG.
It can be seen, and in part c of FIG. 7, the graph (2) of FIG.
And the additive mixing of the blue wavelength (B) and the red wavelength (R)
It looked green due to the principle of color. In this way, the blue
Color image on uniform volume phase diffraction grating diffracting wavelength
Could be formed. As is apparent from the above description, the present invention
According to the method for manufacturing color holograms, interference fringes are recorded
At least one of heat and pressure is applied to the hologram
By applying a partial distribution with a typical distribution,
Shrink the interval of the interference fringes according to their distribution
The interference fringes correspond to the color pattern you want to draw.
By spatially distributing the intervals, pseudo
Production of similar color holograms with continuous color tone with good reproducibility
Wear. Also added from the outline of the part where the reproduction color changes
Numbers, characters, patterns, etc. can be recognized. In addition, interference fringes
Is continuously changing, so the reproduced color of the hologram
It changes continuously and becomes a hologram excellent in design. Ma
Copy the hologram with this information
Then, the additional information part is not duplicated,
Department. Therefore, counterfeit products can be duplicated from original products.
It becomes impossible to manufacture. Also, the hologram information and
The information is formed from the same continuous interference fringes
So, if you try to remove or add additional information,
System information has a missing part, so the tampering history is clear.
Falsification and forgery can be prevented.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing how a reproduction wavelength changes continuously when the interval between interference fringes of a volume hologram changes continuously. FIG. 2 is a diagram illustrating a state in which a reproduction color continuously changes when an interval between interference fringes of a volume hologram changes in a binary manner. FIG. 3 is a view for explaining schematic steps and operations of a method for manufacturing a color hologram according to a reference example of the present invention. FIG. 4 is a view for explaining steps of a hologram swelling method using a swelling film. FIG. 5 is a view for explaining steps of another hologram swelling method using a swelling film. FIG. 6 is a diagram illustrating an example of a mask having an image drawn by a transmittance distribution. FIG. 7 is a diagram illustrating an example of a mask having an image drawn by halftone dot distribution. FIG. 8 is a diagram for explaining schematic steps and operations of the method for manufacturing a color hologram according to the embodiment of the present invention. FIG. 9 is a diagram showing a state in which the reproduction peak wavelength changes according to the irradiation time for the swelling film. [Description of Signs] 1 ... Substrate 2 ... Volume type hologram 3 ... Hologram recording material 4 ... Object light 5 ... Reference light 6 ... Interference fringe 7 ... Printing 8 ... White reproduction light 9 ... Inscription 10 ... Swelling film 11 ... Light irradiation

Claims (1)

(57) [Claim 1] A hologram in which light interference fringes are recorded in a thickness direction of a film, wherein a part of the hologram has a spatial distribution of interference fringes. In a method for producing a color hologram in which the reproduction wavelength from the portion is shortened and different according to the interval between the interference fringes, at least one of heat and pressure is imparted to the hologram on which the interference fringes are recorded by applying a spatial distribution. A method for producing a color hologram, wherein the distance between the interference fringes is reduced according to the distribution by partially applying the interference fringes.