JPH10153943A - Generating method of hologram and hologram - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the quality of a reproduced picture while generating an original picture in a computer by obtaining the optimum arranging region which satisfies a specific condition and arranging the picture in the region. SOLUTION: A personal computer 1 generates an original picture, conducts a Fourier transformation process, repeatedly generates pattern images and stores the image in a floppy disk(FD) 3. A laser scanner 5 reads the repeated pattern images stored in the FD3 and outputs them into a film. Note that the computer 1 and the scanner 5 are directly connected or connected through a network. A region is defined by one side of an arbitrary line which goes through the center of a square having the side length of 2a. Let (r) be the distance from the center. Then, a picture is arranged in the region which satisfies S*F<r/a<M*F (where S and M are constants and F is the function of output pitch) and an original picture is generated. Then, the Fourier transformed picture of the original picture is generated, plural Fourier transformed pictures are made into an array and outputted on a film.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a hologram, and more particularly to a method for producing a hologram for optimizing an optimal arrangement of an original image and a size of a minimum repetition pattern.

[0002]

2. Description of the Related Art Conventionally, when creating a hologram, there is a method in which a Fourier transform image of an original image is created using a computer, a repetitive pattern of the Fourier transform image is created, and the pattern is output to a film or the like.

[0003]

However, when a hologram is formed in this manner, a reproduced image may be deteriorated.

The present invention has been made in view of such a problem, and an object of the present invention is to provide a hologram forming method and a hologram capable of obtaining a high-quality reproduced image.

[0005]

In order to achieve the above-mentioned object, the present invention relates to (a) an area on one side of an arbitrary straight line passing through the center of a square having a side length of 2a, wherein the distance from the center is r. Where S * F <r / a <M * F, where S and M are constants and F is a function of the output pitch. Generating a Fourier transform image of
(C) arranging a plurality of Fourier-transformed images and outputting them on a film.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram of an apparatus for performing a hologram creation method according to one embodiment of the present invention. The personal computer 1 has the original image 3
0 is created, and a process such as Fourier transform is performed to create a repetitive pattern image and stored in the floppy disk (FD) 3. Laser scanner 5 is a floppy disk 3
Is read and output to the film 37 (FIG. 5). The floppy disk 3
Alternatively, an optical disk or the like may be used, the personal computer 1 and the laser scanner 5 may be directly connected, or may be connected via a network.

FIG. 2 is a flowchart showing a method for producing a hologram. First, an original image is created on the personal computer 1 (step 201).

FIG. 3 is an explanatory diagram in the case of creating an original image. In FIG. 3, reference numeral 20 denotes an original image. As an original image 20, a square with CO at the center and one side 2a is considered. The center CO corresponds to the light source position at the time of reproduction. For example, characters, pictures, and the like are arranged in the square of one side 2a. When a Fourier-transformed image is reproduced, the reproduced image is point-symmetrical. Therefore, as the original image 20, characters or the like are arranged only on one side of a straight line 22 passing through the center CO. For example, as shown in FIG. 3, characters and the like are arranged in an area above the straight line 22. The inclination of the straight line 22 is arbitrary as long as it passes through the center CO.

Next, assuming that the distance from the center is r, S * F <r / a <M * F (1) (where S and M are constants and F is a function of the output pitch) Characters and the like are arranged in an area that satisfies. In equation (1), S * F takes into account that when a character or the like is reproduced too close to the center (light source) CO, it cannot be seen with the eyes. Also, in equation (1), M * F
Takes into account that if it is too far from the center CO, it cannot be seen with the eyes due to insufficient light quantity.

When the distance from the center is r, 0.01x <r / a <0.132x (1 ') where x is a character in an area satisfying the output pitch (μm / dot). And so on. In the case of FIG. 3, the area 24 satisfying the expression (1 ′) is the hatched area 24.

FIG. 4 is a diagram showing an experimental result for determining the range of r / a. That is, several original images are prepared such that the edges of the reproduced image become invisible at the time of reproduction, the output pitch is changed for each original image, holograms are created, the reproduced images are observed for each hologram, and the reproduced images are observed. The position where it disappears is obtained and converted into the distance from the center. By conducting such an experiment, Expression (1 ′) was obtained.

Next, in order to create a Fourier transform image,
The original image 20 is rearranged, and an image 30 is obtained. As shown in FIG. 3, the original image 20 is divided into four parts,
23, 25 and 27 are obtained. In order to obtain a Fourier transform image, the center CO of the original image 20 needs to be located at four corners in the image 30. Therefore, the region 21 is located at the lower left on the image 30, and the regions 23, 25, and 27 are hereinafter referred to as FIG.
Are rearranged as shown in FIG.

In this way, the original image 30 is created in step 201 of FIG. Note that the created original image 30 is shown on the right side of FIG. Next, in FIG. 2, a Fourier transform image of the original image is created using a computer. The Fourier transform image 31 of the original image 30 is shown on the right side of FIG. Next, the Fourier transform image is binarized (step 203). That is, the phase is checked for each pixel of the Fourier transform image, and when the phase is from minus 90 degrees to plus 90 degrees, a certain value Tp (for example, transparent) is assigned,
In other cases, binarization is performed by assigning another certain value Tm (for example, black). The range in which Tp is assigned may be other than minus 90 degrees to plus 90 degrees. Further, the range to which Tp is assigned can be determined not from the phase but from the amplitude.

On the right side of FIG. 2, a binarized Fourier transform image 32 is shown. Then, a reproduced image is simulated (step 204). In this simulation, an inverse Fourier transform is performed on the binarized Fourier transform image to obtain a reproduced image, and it is checked whether or not the processing in each of the above-described steps has been properly performed. On the right side of FIG. 2, a reproduced image 33 obtained by the simulation is shown. If the original image is not appropriate, the process returns to step 201 again. Next, the binarized Fourier transform image obtained in step 203 is arranged to a desired range (step 205). For example, an image 34 is obtained by arranging four binarized Fourier transform images 32. Actually, for example, ten images 32 of the minimum unit are arranged vertically and horizontally, for example.

Next, the image is output to the film 37 using the laser scanner 5 (step 206). That is, a hologram is created. FIG. 5 shows an image output on the film 37, and 35 is a minimum repeating pattern.
Then, as shown in FIG. 5, the size A of the minimum repeating pattern 35 on the film 37 is determined as follows. B <A <C (2) where B: output pitch (μm / dot) * minimum number of pixels (dot) required to form a character or picture C: function determined by distance between pupil and film , The number of pixels of the minimum repetition pattern is the number of pixels required to reproduce the detail, and is appropriately determined.

The minimum repeating pattern 35 corresponds to the binarized Fourier transform image 32. The Fourier transform image 32 is image data held in the personal computer 1, whereas the minimum repetition pattern 35 is image data actually output to the film 37. In the equation (2), B is determined by the output pitch of the laser scanner 5, for example, 7 μm / dot * 6.
4dot = 448 μm.

FIG. 6 is a diagram showing a method for determining C in equation (2). In FIG. 6, 41 is an eyeball, 43 is a pupil,
45 is the center of the eyeball 41. If the radius h1 of the eyeball 41 is, for example, 10 mm, the diameter d1 of the pupil 43 is 2 mm, and the distance d2 from the pupil 43 to the film 37 is 20 mm, the diameter d3 of the visible area 46 of the film 37 is d1 / h1 = d3 / (h1 + d2). ), D3 = (h1 + d2) * d1 / h1 = (10 + 20) * 2/10 = 6 mm. This diameter d3 is defined as C in the equation (2). In this way, B and C in Expression (2) are determined, and A is determined so as to satisfy Expression (2).

In FIG. 2, steps 201 to 205 are processed in the personal computer 1, and the image obtained in step 205 is stored in the floppy disk 3. In step 206, the laser scanner 5 reads an image stored in the floppy disk 3 and performs processing. In addition, the image 3 of the minimum unit
2 and the minimum and vertical numbers of the image 32 of the minimum unit to be arranged on the film may be recorded on the FD 3, and the laser scanner 5 may output the image on the film.

FIGS. 7 and 8 are diagrams for explaining the case where an image is reproduced using the film obtained in step 206. FIG. In FIG. 7, reference numeral 51 denotes a person, and 55 denotes a point light source. A point light source 55 is arranged behind the film 37, and when the person 51 looks at the film 37, an image 57 that is point-symmetric around the point light source 55 can be seen corresponding to the image in the film 37. Further, the film 37 may be used as a lens of the spectacles. Such glasses are used as children's toys.

In FIG. 8, 52 is a person, 54 is a mirror, 56
Is a point light source, and 58 is a point light source reflected on the mirror 54. The film 37 is disposed in front of the mirror 54, and a point light source 56 is disposed in front of the film 37. When the person 52 views the film 37, the point light source reflected on the mirror 54 corresponds to the image in the film 37. An image 59 that is point symmetric around 58 can be seen. Note that a reflective film such as a half mirror, glass, or a film on which aluminum is deposited may be used as the mirror 54. As described above, in the present embodiment, step 2 in FIG.
In step 01, when an original image is created in a computer, characters and the like are arranged in order to determine the optimal arrangement range of characters and pictures, so that the quality of a reproduced image is improved.

In step 206, the optimum size of the minimum repetition pattern A is calculated and the image is output to a film, so that the quality of the reproduced image is improved.

[0022]

As described in detail above, according to the present invention, it is possible to provide a hologram forming method and a hologram capable of obtaining a high-quality reproduced image.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an apparatus for implementing a hologram creating method.

FIG. 2 is a flowchart showing a hologram creation process;

FIG. 3 is an explanatory diagram showing an original image creation process.

FIG. 4 is a diagram showing a relationship between an output pitch x and r / a.

FIG. 5 shows a film 37.

FIG. 6 is an explanatory diagram for determining the size of a minimum repeating pattern 35;

FIG. 7 is an explanatory diagram of a case where an image is reproduced using a film 37.

FIG. 8 is an explanatory diagram when an image is reproduced using a film 37;

[Explanation of symbols]

 1 Personal computer 3 Floppy disk 5 Laser scanner 37 Film

Claims (10)

[Claims] 1. (a) In an area on one side of an arbitrary straight line passing through the center of a square having a side length of 2a, assuming that a distance from the center is r, S * F <r / a <M * F. S and M are constants. F is a function of an output pitch. A step of arranging an image in an area that satisfies the following equation: (b) a step of generating a Fourier transform image of the original image; and (c) a step of generating a Fourier transform image. Arranging a plurality of holograms on a film and outputting the holograms on a film. 2. (a) In an area on one side of an arbitrary straight line passing through the center of a square having a side length of 2a, assuming that a distance from the center is r, 0.01x <r / a <0.132x x is a step of arranging an image in an area satisfying the output pitch (μm / dot) to create an original image; (b) a step of generating a Fourier transform image of the original image; and (c) a plurality of Fourier transform images. A method of arranging the holograms and outputting the holograms on a film. (A) a step of creating an original image; (b) a step of generating a Fourier transform image of the original image; and (c) transforming the Fourier transform image with a repetition pattern of size A satisfying the following conditions: B <A <C, where B: output pitch (μm / dot) * minimum number of pixels (dot) required to form a character or picture C: determined by distance between pupil and film (D) outputting an arrayed Fourier transform image on a film. 4. (a) An area on one side of an arbitrary straight line passing through the center of a square having a side length 2a, where r is the distance from the center, and S * F <r / a <M * F. S and M are constants. F is a function of an output pitch. A step of arranging an image in an area satisfying the following equation: (b) a step of generating a Fourier transform image of the original image; Arranging a plurality of Fourier transform images in a repetitive pattern having a size A satisfying the following condition: B <A <C, where B: output pitch (μm / dot) * minimum necessary pixels for forming a character or picture A number (dot) C: a function determined by the distance between the pupil and the film; and (d) a step of outputting the arranged Fourier transform images on a film. 5. (a) In an area on one side of an arbitrary straight line passing through the center of a square having a side length of 2a, assuming that the distance from the center is r, 0.01x <r / a <0.132x. x is a step of arranging an image in an area satisfying an output pitch (μm / dot) to create an original image; (b) a step of generating a Fourier transform image of the original image; and (c) satisfying the following conditions: Arranging a plurality of Fourier transform images in a repetitive pattern of size A; B <A <C, where B: output pitch (μm / dot) * minimum number of pixels required to form a character or picture ( (d) a function determined by the distance between the pupil and the film; and (d) a step of outputting the arranged Fourier transform images on a film. 6. The hologram according to claim 1, wherein the Fourier transform image is binarized, and a plurality of binarized Fourier transform images are arranged on a film. How to make. 7. The hologram creating method according to claim 1, further comprising a step of generating an inverse Fourier transform image from the generated Fourier transform image. 8. An area on one side of an arbitrary straight line passing through the center of a square having a side length of 2a, where S is a distance from the center, and S * F <r / a <M * F. Is a constant, F is a function of the output pitch. A hologram is formed by arranging an image in an area satisfying an output pitch, forming an original image, and arranging a plurality of Fourier transform images of the original image on a film. 9. An area on one side of an arbitrary straight line passing through the center of a square having a side length of 2a, where r is a distance from the center, and 0.01x <r / a <0.132x, where x is an output. A hologram in which a plurality of Fourier transform images of an original image created by arranging images in a region satisfying a pitch (μm / dot) are arranged on a film. (A) generating a Fourier transform image of the original image; and (b) arranging a plurality of Fourier transform images in a repeating pattern of size A satisfying the following condition: B <A <C, where B <A <C : Output pitch (μm / dot) * Minimum number of pixels (dot) required to compose a character or picture C: Function determined by distance between pupil and film (c) Output arranged Fourier transform image on film A hologram made by you.