JP3504285B2 - Hologram creation method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hologram creating method and apparatus, and more particularly, to providing a high degree of anti-counterfeiting effect by making optical duplication of a hologram difficult, and a higher level of security. The present invention relates to a method and an apparatus for producing a hologram.

[0002]

2. Description of the Related Art In recent years, holograms have been used in various fields as a technique for displaying three-dimensional information of an object by making good use of light interference and diffraction phenomena. Among them, recently, holograms have been increasingly used in the field of forgery prevention.

That is, for example, in printed matter such as gift certificates and stock certificates, cards such as credit cards and prepaid cards, forgery is a problem. For this reason, a hologram forgery preventing means has been taken for the purpose of preventing itself from being forged.

However, the hologram can be optically duplicated although the image quality is deteriorated, and the data can be easily read by shining laser light or white light. it can. For this reason, not only the counterfeiting attempt to copy the hologram cannot be effectively prevented, but there is a problem in terms of security (data confidentiality is maintained).

[0005]

As described above, in the conventional hologram forgery prevention, not only forgery is easily performed, but also there is a problem in terms of security.

The present invention is a hologram in which a plurality of dot-shaped element holograms are formed on the surface of a base material, and by changing the pattern of reference light for each element hologram,
An object of the present invention is to provide an extremely reliable hologram production method and apparatus capable of imparting a high degree of anti-counterfeiting effect by making optical duplication of a hologram difficult and having a higher degree of security. .

[0007]

To achieve the above object, according to an aspect of how to create a hologram of the present invention, the hologram creation method by forming a plurality of element holograms dot-like to the substrate surface, light Reference light by intensity modulation member
Change the intensity of the pattern for each element hologram,
The pattern of the reference light whose intensity is changed for each element hologram.
The corresponding element hologram is optically recorded on the surface of the substrate by using a lens.

In order to achieve the above object, another hologram producing method of the present invention is a hologram producing method in which a plurality of dot-shaped element holograms are formed on a surface of a base material, and data to be recorded is recorded. Alternatively, enter the image into the computer and set the reference light pattern.
Steps to enter into the computer and enter into the computer
From the applied data or image and the reference light pattern, the step of calculating the pattern on the object light side and the reference light side corresponding to the coordinate position of the light collector on the hologram dry plate, and the step of calculating the light collector on the hologram dry plate. The step of displaying the pattern on the object light side and the reference light side corresponding to the coordinate position on the light intensity modulation member on the object light side and the reference light side, and hologram for the object light and the reference light using at least an optical system. The step of forming dot-shaped element holograms corresponding to each display pattern on the hologram dry plate by causing interference in the light focus on the dry plate, and the coordinate position of the light focus on the hologram dry plate are sequentially moved to perform the above calculation. Repeat the steps of displaying, and forming element holograms to form multiple dot-shaped element holograms on the hologram plate. That consists of a step, and a reference light pattern is focused on the hologram dry plate to form the element holograms while changing for each elementary hologram.

Further, in order to achieve the above object,
The hologram producing apparatus of the present invention is a hologram producing apparatus in which a plurality of dot-shaped element holograms are formed on a surface of a base material, and a moving means for moving a hologram dry plate to a desired position, recorded data or an image and reference. A pattern creating means for obtaining the pattern on the object light side and the reference light side corresponding to the coordinate position of the condensing part on the hologram dry plate from the light pattern, and the object corresponding to the coordinate position of the condensing part on the hologram dry plate The light intensity modulation members on the object light side and the reference light side for displaying the patterns on the light side and the reference light side, and the object light and the reference light on the hologram dry plate at the condensing part on the hologram dry plate. Each pattern of the condensed reference light
An optical system that forms dot-shaped element holograms corresponding to each display pattern displayed on each light intensity modulation member on a hologram dry plate by changing and interfering with each element hologram, and a hologram in which a plurality of element holograms are formed. It comprises a developing means for developing the dry plate, a moving means, a pattern creating means, and a control means for controlling the developing means to create a hologram.

Here, particularly as the light intensity modulation member , an amplitude modulation element such as a liquid crystal panel can be considered, and it is preferable that the hologram dry plate is a Lippmann hologram dry plate.

[0011]

Therefore, in the hologram producing method and apparatus of the present invention, since the pattern of the reference light is different for each element hologram based on the encryption, it becomes difficult to optically duplicate the hologram, and it is extremely advanced. It can have an anti-counterfeiting effect.

Also, as a hologram display pattern,
When data to be read by the sensor is input, it is necessary to use the same light as the reference light at the time of shooting as the illumination light. It is possible to add security (enhance the confidentiality of data).

Further, as dummy data, different data is superposed on different holograms with different reference patterns on the same element hologram so that false reading data can be obtained in case of wrong illumination pattern. -You can also display the data.

On the other hand, the hologram of the present invention is a plane type,
It can be synthesized in one step.

Further, in the manufacturing method and apparatus of the present invention,
By sequentially recording dot-shaped element holograms on the surface of the base material, it is possible to perform recording in a manner similar to that of a conventional dot printer.

[0016]

EXAMPLES The present invention is, in a hologram by forming a dot-shaped plural element holograms on the substrate surface, encryption
Based on the above, by changing the pattern of the reference light for each element hologram, optical duplication is made difficult and the anti-counterfeiting effect is enhanced, and the illumination light is used as a cryptographic key to improve security (data tightness). Sex).

An embodiment of the present invention based on the above concept will be described below in detail with reference to the drawings.

First, the principle on which the present invention is based will be described with reference to FIGS. 1 and 2 in the case where a Lippmann type hologram is used as a hologram.

The production method of the present invention shown in FIG. 2 is similar to the method of recording parallax information in the conventional multiplex hologram shown in FIG. 1, but the multiplex hologram is Whereas only the parallax in the direction is recorded, the method of the present invention records the parallax information also in the vertical direction. In this method, a thick hologram is used to form a Lippmann hologram so that the light to be reproduced has wavelength selectivity, and the vertical parallax is reproduced by white light illumination.

Next, the optical system used in the manufacturing method of the present invention will be described with reference to FIG.

An object light pattern created by a computer from recorded data or an image is displayed on a liquid crystal panel 10o which is an amplitude modulation element as a display means, and the object light which is the transmitted light is hologramed through a lens 12o. The light is focused on the surface (hologram dry plate) 14.

Further, the reference light pattern created by a computer from the reference light pattern is displayed on the liquid crystal panel 10r which is an amplitude modulation element as the display means, and the reference light which is the transmitted light is passed through the lens 12r. The interference fringe pattern of the object light and the reference light is made incident on the light condensing portion 16 of the hologram surface (hologram dry plate) 14 from the opposite direction, and is recorded on the hologram surface 14 as a dot-shaped element hologram.

Then, the hologram film is moved little by little in the vertical and horizontal directions for sequential exposure to expose the entire hologram surface with dot-shaped element holograms. In this case, exposure is performed while changing the pattern of the reference light for each element hologram.

Next, with reference to FIG. 4, a hologram production system using the one-step Lippmann HS will be specifically described.

FIG. 4 is a schematic diagram showing a concrete example of the configuration of the system. In FIG. 4, helium neon ray
The laser beam from the laser 20 is separated into object light and reference light by a beam splitter 22.

Of these, the object light becomes parallel light through the lens 24o, illuminates the liquid crystal panel 10o, and is amplitude (intensity) modulated by the liquid crystal panel 10o. Further, the amplitude-modulated object light is transmitted through the lens 26o and the slit 28.
o, the lens 30o, and the mirror 32o to guide it to a spherical lens 34o having a large power.
O is focused on the hologram surface 14. Here, the lens 26o, the slit 28o, and the lens 30
o constitutes a spatial filtering system for removing the matrix structure of the liquid crystal panel 10o.

Further, the reference light becomes parallel light through the lens 24r, illuminates the liquid crystal panel 10r, and the liquid crystal panel 1
The amplitude (intensity) is modulated by 0r. Further, the amplitude-modulated object light is reflected by the lens 26r, the slit 28r,
Further, it is guided to a spherical lens 34r having a large power through a lens 30r and a mirror 32r, and is focused on the hologram surface 14 by this lens 34r. Here, the lens 26r, the slit 28r, and the lens 30r are
A spatial filtering system for removing the matrix structure of the liquid crystal panel 10r is configured.

On the other hand, the hologram surface 14 has an XY station.
It is fixed to the jig 36 and is movable in the vertical and horizontal directions. Then, while changing the information of the liquid crystal panels 10o and 10r,
By moving the XY stage 36, a dot-shaped element hologram is formed on the entire surface of the hologram surface 14. The entire system is controlled by a personal computer. As the sensitive material used for the hologram surface 14, for example, a silver salt sensitive material can be used.

Next, the HS according to the present invention has the following features.

(A) A parallax in the horizontal and vertical directions can be added, and a complicated image can be displayed.

(B) If a Lippmann type hologram is used, it is basically possible to realize a real color.

(C) It can be synthesized by a small device without using a special optical component such as a cylindrical lens.

(D) When creating a large hologram,
It is only necessary to use the exact same optical system and increase the number of exposure points.

(E) Since the light beam is condensed and used, the power of the light source can be effectively used, and high stability of the optical system is not required.

(F) Since it can be synthesized in one step, it can be used in an automatic system.

Next, referring to FIGS. 5 and 6, an example of the configuration of the hologram creating apparatus (printer) according to the present invention will be described.

Note that, in FIG. 5, in the optical system 48, the two optical systems are drawn so as to form a right angle with each other for convenience of arrangement in the drawing, but in reality, as shown in FIG. , Are arranged on almost the same straight line.

This printer is used in an image like a video printer. The operator can obtain a hologram with a high degree of security by observing the image on the monitor from various angles and setting the output direction.

That is, first, in step A of FIG. 6, the data or image to be recorded is input to the host computer 40.

Next, in step B, the reference light pattern
Input to the host computer 40.

Next, at step C, the hologram dry plate 14 is moved by the film moving controller 46 to set the hologram dry plate 14 at a desired position (origin of the exposure position).

Next, in step D, the graphic processor 42 uses the recorded data / image to
The pattern on the object light side corresponding to the coordinate position of the condensing portion on the hologram surface 14 is calculated, and the pattern on the reference light side corresponding to the coordinate position of the condensing portion on the hologram surface 14 is calculated from the reference light pattern. The calculated frames are stored in the frame memory 44.

Next, in step E, the liquid crystal panel 1
The pattern on the object light side is displayed at 0o, and the pattern on the reference light side is displayed on the liquid crystal panel 10r.

Next, in step F, the shutter of the optical system 48 is opened to expose the liquid crystal panels 10o and 10r, respectively. The laser light extracted from the laser device 20 is divided into object light and reference light by the beam splitter 22, and the object light is amplitude-modulated by the pattern of the liquid crystal panel 10o and the hologram surface 14 The reference light is amplitude-modulated by the pattern of the liquid crystal panel 10r, is condensed on the hologram surface 14 from the opposite side, and one element hologram is formed by the object light and the reference light.

Next, in step G, the hologram dry plate 14 is sequentially moved by the film moving controller 46, and the operations of steps D, E, and F are repeated until the exposure is completed via step H. The hologram surface 14 is exposed so as to fill the entire surface. In this case, in step D, the reference light pattern different for each element hologram is calculated from the reference light pattern, and in step E, the reference light side pattern different for each element hologram is displayed on the liquid crystal panel 10r. Display.

Thereafter, in step I, the developing process of the hologram 14 is performed by the developing machine 50, and the hologram is automatically created.

The graphic processor 42, the film moving controller 46, and the developing machine 50 are C
It is controlled by the PU.

By using such a holographic / three-dimensional printer system, a hologram with a high image quality can be created completely automatically.

On the other hand, the optical duplication of the hologram is performed as follows.

That is, in the case of the Lippmann hologram,
A photosensitive material is overlaid on the hologram, and laser light is illuminated from above. In this case, in the photosensitive material, the illumination light as the reference light from above interferes with the reproduction light of the hologram as the object light from below, and is recorded as a hologram. Since the Lippmann hologram has wavelength selectivity and reproduces an image only under illumination at a certain angle, the incident angle of the illuminating laser is limited to a certain angle.

In this respect, in the hologram of the present embodiment created as described above, since the pattern of the reference light is different for each element hologram, in order to perform optical duplication, It is necessary to change the lighting pattern, and in reality, optical duplication is impossible.

As a result, a high degree of forgery prevention effect can be provided.

Also in reading data, since the illumination light pattern is different for each element hologram, a bright reproduced image cannot be obtained unless the reference light pattern at the time of recording is known. .

Further, as dummy data, different data is superposed on different holograms with different reference patterns on the same element hologram so that false reading data can be obtained in case of wrong illumination pattern. -It is also possible to display the data.

As a result, it is possible to provide a higher level of security (enhance the confidentiality of data).

As described above, in the present embodiment, the data or image to be recorded and the reference light pattern are input, and the recorded data or image and the reference light pattern are set to the coordinate position of the converging portion on the hologram surface 14. The corresponding patterns on the object light side and the reference light side are calculated, and the patterns on the object light side and the reference light side corresponding to the coordinate position of the condensing portion on this hologram surface 14 are referred to as the object light side and the reference light side. Display on the liquid crystal panels 10o and 10r on the light side, and dot-shaped element holograms corresponding to each display pattern are formed on the hologram surface 14 using the optical system.
By sequentially moving and displaying the coordinate position of the light collecting portion on 4 and forming element holograms, a plurality of dot-shaped element holograms are formed on the hologram surface 14, and are condensed on the hologram surface 14. The element hologram is formed by changing the pattern of the reference light for each element hologram.

Therefore, the following various effects can be obtained.

(A) Since the pattern of the reference light is different for each element hologram, it is difficult to optically reproduce the hologram, and it is possible to provide a high anti-counterfeiting effect.

(B) As a hologram display pattern,
When the data to be read by the sensor is input, it is necessary to use the same light as the reference light at the time of shooting as the illumination light, so the reference light pattern is encrypted, that is, the illumination light is the key for encryption. It is possible to provide a higher level of security (enhance the confidentiality of data).

(C) Object light pattern on the same element hologram
Multiple exposures are performed by changing the beam and reference beam patterns, that is, as the data of the dummy, different data are superposed on the same element hologram by different reference patterns. By the wrong lighting pattern,
It is possible to display fake read data, and it is possible to further enhance security (data confidentiality).

(D) In the hologram according to this embodiment, since the image can be reproduced by the dot-shaped element hologram, there is no limitation on the size of the hologram and there is no unevenness on the entire surface of the hologram.

(E) According to the producing method of this embodiment, a three-dimensional hologram can be produced with one optical system. Further, the laser light can be effectively used and the exposure time is short, so that it is not affected by external vibration.

(F) According to the hologram creating apparatus (printer) of this embodiment, it is possible to automatically create a hologram.

The present invention is not limited to the above embodiments, but can be carried out in various modifications as follows without departing from the spirit of the present invention.

(A) In the above embodiment, as the display means,
The case of using a liquid crystal panel which is an amplitude modulation element for amplitude-modulating laser light has been described, but the invention is not limited to this, and the number of pixels is 256 × for use in this system.
An amplitude modulation element capable of expressing 8-bit gradation at 256 or more and capable of displaying an image with low noise even in coherent light illumination is preferable. For example, a mask may be used.

(B) In the above embodiment, the case where the liquid crystal panels 10o and 10e for modulating the light intensity are used as the display means on the object light side and the reference light side has been described. A slit, a light-shielding mask, a film, or the like may be used for one or both of the display means.

(C) In the above embodiments, the case where the Lippmann hologram dry plate is used as the hologram dry plate has been described, but the hologram dry plate is not limited to this, and other hologram dry plates may be used.

(D) In the above embodiments, the silver salt sensitive material was used as the sensitive material, but a polymer photosensitive material may be used for recording a Lippmann hologram with high image quality.

[0069]

As described above, according to the present invention, it is possible to impart a high degree of anti-counterfeiting effect by making optical duplication of a hologram difficult, and a higher degree of security. It is possible to provide a possible method and apparatus for producing a hologram with extremely high reliability.

[Brief description of drawings]

FIG. 1 is a diagram for explaining the principle of a conventional multiplex hologram.

FIG. 2 is a diagram for explaining the principle of a multi-dot hologram which is the premise of the present invention.

FIG. 3 is a schematic diagram showing an optical system of a one-step Lippmann HS according to the present invention.

FIG. 4 is a schematic diagram showing a detailed optical system for Lippman HS synthesis according to the present invention.

FIG. 5 is a schematic diagram showing a configuration example of a holographic printer system of the present invention.

6 is a flowchart of the holographic printer system in FIG.

[Explanation of symbols]

10o, 10r ... Liquid crystal panel, 12o, 12r, 24
o, 24r, 26o, 26r, 30o, 30r, 34
o, 34r ... Lens, 20 ... Laser, 22 ... Beam splitter, 28o, 28r ... Slit, 32o, 32r ...
Mirror, 36 ... XY stage, 40 ... Host computer, 42 ... Graphic processor, 44 ... Frame
Memory, 46 ... Film moving controller, 48 ... Optical system, 50 ... Developing machine.

─────────────────────────────────────────────────── ─── Continuation of front page (73) Patent holder 591211054 Nagaaki Oyama 2-3-9 Kannon, Kawasaki-ku, Kawasaki-shi, Kanagawa (72) Inventor Susumu Takahashi 1-5-1, Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. (72) Inventor Masahiro Yamaguchi 4-1-31-502 Kamada, Setagaya-ku, Tokyo (72) Inventor Kazuo Honda 1913-12 Kitahachisaku-cho, Midori-ku, Yokohama, Kanagawa (72) Inventor Nagaaki Oyama, Kawasaki, Kanagawa 2-3-9 Kannon, Kawasaki-ku (56) Reference JP-A-4-93881 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03H 1/00-5/00

Claims (5)

(57) [Claims] 1. A method for producing a hologram comprising a plurality of dot-shaped element holograms formed on a surface of a base material , wherein the intensity of a pattern of reference light is adjusted by a light intensity modulating member.
Each element hologram is changed for each element hologram.
Use the reference light pattern whose intensity is changed for each
A method for producing a hologram, in which an element hologram to be recorded is exposed and recorded on the surface of the substrate . 2. A method for producing a hologram comprising a plurality of dot-shaped element holograms formed on a surface of a substrate, the step of inputting data or an image to be recorded to a computer, and the step of inputting a reference light pattern to the computer. Calculating a pattern on the object light side and the reference light side corresponding to the coordinate position of the condensing part on the hologram dry plate from the data or image input to the computer and the reference light pattern; The step of displaying the pattern on the object light side and the reference light side corresponding to the coordinate position of the light condensing part on the light intensity modulation member on the object light side and the reference light side, and the object light using at least an optical system. By causing the reference light to interfere at the condensing part on the hologram dry plate, the hologram dry plate Forming a dot-shaped element hologram corresponding to each display pattern; sequentially moving the coordinate position of the light condensing part on the hologram dry plate to calculate; displaying; and forming the element hologram Repeating the steps to form a plurality of dot-shaped element holograms on the hologram dry plate, the element holograms are formed while changing the pattern of the reference light focused on the hologram dry plate for each of the element holograms. A method of creating a hologram, characterized in that 3. A hologram producing apparatus in which a plurality of dot-shaped element holograms are formed on a surface of a base material, and moving means for moving a hologram dry plate to a desired position, and recording data or an image and a reference light pattern. Pattern forming means for obtaining patterns on the object beam side and the reference beam side corresponding to the coordinate position of the light condensing part on the hologram dry plate, and the object corresponding to the coordinate position of the light converging part on the hologram dry plate Light intensity modulation members on the object light side and the reference light side that display the patterns on the light side and the reference light side, and the object light and the reference light are condensed on the hologram dry plate at the light collecting part on the hologram dry plate. Reference light pattern
An optical system for forming dot-shaped element holograms corresponding to each display pattern displayed on each of the light intensity modulation members on the hologram dry plate by changing and interfering with each other for each element hologram; A hologram, comprising: a developing means for developing the hologram dry plate having a plurality of formed thereon; a moving means, the pattern creating means, and a control means for controlling the developing means to create a hologram. Creation device. 4. The hologram creating apparatus according to claim 3, wherein the light intensity modulation member is an amplitude modulation element such as a liquid crystal panel. 5. The hologram creating apparatus according to claim 3, wherein the hologram dry plate is a Lippmann hologram dry plate.