JP2009217137A - Information recording method, information recording device, microfilm, information reproducing method, and information reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information recording method, an information recording device and the like, capable of recording digital information of a document in a microfilm in the form of a hologram by correlating the digital information and analog information of the document in such a manner that the digital information of the document can be read out separated from the analog information by using the document. <P>SOLUTION: The hologram is recorded by allowing the reflected object light obtained by irradiating a document to be recorded with light to interfere with the signal light modulated by a digital image that represents digital data of the document to be recorded as a bright and dark image. When the hologram is irradiated with the same reflected object light used in recording as readout light, the signal light is reproduced. When digital information is reproduced, the document (reflected object light from the document) is used to selectively reproduce only the digital information, and thereby credence of the reproduced digital information is ensured. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an information recording method, an information recording apparatus, a microfilm, an information reproducing method, and an information reproducing apparatus.

  Conventionally, recording media called microfilms and microfiche (hereinafter referred to as “microfilms”) have been used for long-term storage of documents such as storage of official documents. Since a silver salt light-sensitive material having excellent storability is usually used for microfilms, microfilms on which documents are recorded (hereinafter referred to as “microfilm documents”) can be stored for a long period of 100 years or longer. It is.

  In addition, on microfilm, a reduced image (usually a positive image) of each document (page) included in a document is given a frame number for each document on a single film or sheet in an analog format. It is recorded in order. When reading document information from a microfilm document, a browse document and a browse page are specified by a frame number, and a recorded reduced image is optically enlarged and displayed on a display.

  Microfilm documents have the advantage that they can be read by being optically enlarged, and that tampering can be prevented in principle. Actually, microfilm documents have the same legal evidence ability as the original because of the characteristics of reproducing information as it is and the fact that the format is internationally standardized and standardized by JIS, ISO, etc. (Evidence) has been proven in domestic and foreign cases.

  For example, when recording and saving official documents using microfilm, in order to ensure the authenticity of the document, a resolution chart, a photography request form, subject, contents, and photography before and after the document to be saved (document representing the text) Place a certificate etc., insert the text between them, and record it on the microfilm. In this way, by defining the format to include at least the document that represents the beginning, the document that represents the body, and the document that represents the last, the evidence of a document consisting of a series of documents, as long as the film is not cut and pasted. Is secured.

  On the other hand, in recent years, digitization of document information recorded in an analog format such as a paper document and a microfilm document has been promoted. Advantages of computerization are as follows: 1) According to computerized data, various types of document information such as paper documents, microfilm documents, and electronic documents can be integrated and managed 2) Smooth conversion and distribution of document information between companies 3) Document information of microfilm documents can be effectively used as data on a personal computer at hand.

  For example, there is a “method and apparatus for long-term document storage” that converts document information stored in a digital format into an analog format, and writes the document information in the analog format to an analog medium that can be stored for a long period of time It has been proposed (see Patent Document 1).

JP 2002-202903 A

  However, a microfilm or the like on which a reduced image of a document is recorded has a limited recording capacity. For example, a standard microfilm is a roll film having a width of 16 mm and a length of 66 m, and even if each page is photographed and recorded at a reduction of 1/40, one roll of film is used. Can only record about 6000 documents. In addition, since document information is recorded only in an analog format, it is pointed out that it is not easy to use from the viewpoint of searchability, for example, keyword search is not possible.

  On the other hand, simply digitizing causes a serious problem that the document evidence is lost. Document information recorded in an analog format has high evidence because it is analog. If this document information is managed only with digital information, it becomes easy to falsify, and as a result, evidence is lost. Even in the technique described in Patent Document 1, document proof is already lost because it is managed only by computerization at the time of storage. That is, it is difficult to achieve both “digital convenience” and “analog evidence”.

  The present invention can record digital information of a document on a microfilm in the form of a hologram in association with the digital information of the document and the analog information so that the document can be read separately from the analog information of the document. An object of the present invention is to provide an information recording method and an information recording apparatus.

  The present invention also relates to a micro-recording method in which digital information of a document is recorded in a hologram format in association with the digital information and analog information so that the digital information of the document can be read separately from the analog information of the document. The object is to provide a film.

  Further, the present invention can read digital information of a document separately from the analog information of the document by using the document from the microfilm recorded in the hologram format in association with the digital information and analog information of the document. An object of the present invention is to provide an information reproducing method and an information reproducing apparatus.

  In order to achieve the above object, an information recording method according to claim 1, wherein information on a document is recorded on a microfilm as a first hologram by interference between a reflected object light and a reference light of the document, The digital data is recorded on the microfilm as a second hologram by interference between signal light modulated by a digital image represented by a light and dark image and reflected object light of the document.

  The information recording method according to claim 2 is the information recording method according to claim 1, wherein the reference light is signal light modulated by a digital image representing digital data of the document as a light and dark image, The first hologram and the second hologram are one hologram.

  The information recording apparatus according to claim 3, wherein a light source that emits coherent light, a branching unit that branches the coherent light emitted from the light source into two light waves, and one light wave branched by the branching unit Irradiating the microfilm with object light generating means for generating reflected object light of the document and adjusting the optical path of the reflected object light generated by the object light generating means Adjusting the light path of the other light wave branched by the branching means, and irradiating the light wave simultaneously with the reflected object light at a position where the reflected object light of the microfilm is irradiated A reference light irradiating means and a plurality of pixels for displaying a digital image representing the digital data of the document as a light and dark image, and modulating incident light for each pixel in accordance with the displayed digital image A spatial light modulator, adjusting the optical path of the other light wave branched by the branching means, causing the light wave to enter the spatial light modulator, and according to a digital image displayed on the spatial light modulator The signal light generating means for modulating and generating the signal light and the optical path of the signal light generated by the signal light generating means are adjusted, and the reflected object light of the microfilm is irradiated to the signal light Signal light irradiating means for irradiating at a position simultaneously with the reflected object light is provided.

  The information recording apparatus according to claim 4, wherein a light source that emits coherent light, a branching unit that branches the coherent light emitted from the light source into two light waves, and one light wave branched by the branching unit The object light generating means for generating the reflected object light of the document and the optical path of the reflected object light generated by the object light generating means are adjusted to irradiate the microfilm with the object light A spatial light modulator that displays a digital image representing the digital data of the document as a light and dark image using a plurality of pixels and modulates incident light for each pixel according to the displayed digital image. Comprising adjusting the optical path of the other light wave branched by the branching means, causing the light wave to enter the spatial light modulator, and modulating the light wave according to the digital image displayed on the spatial light modulator, Adjusting the optical path of the signal light generated by the signal light generating means for generating the signal light, and the signal light at a position where the reflected object light of the microfilm is irradiated Signal light irradiating means for irradiating simultaneously with the reflected object light.

  The microfilm according to claim 5, wherein the document information is recorded as a first hologram due to interference between the reflected object light and the reference light of the document, and the digital image representing the digital data of the document as a light and dark image And recorded as a second hologram by the interference between the signal light modulated in step 1 and the reflected object light of the document.

The microfilm according to claim 6 is the microfilm according to claim 5, wherein the reference light is signal light modulated by a digital image representing a digital data of the document as a light-dark image, The hologram and the second hologram are one hologram,
It is characterized by that.

  The information reproducing method according to claim 7, wherein the document information is recorded as a first hologram by interference between the reflected object light and the reference light of the document, and digital data representing the document digital data as a light and dark image An information reproducing method for reproducing information of a document from a microfilm recorded as a second hologram by interference between signal light modulated by an image and reflected object light of the document, wherein the reference light is applied to the first hologram. Irradiating to reproduce an analog image of the document, and irradiating the second hologram with reflected object light of the document to reproduce a digital image of the document or digital data corresponding to the digital image .

  The information reproduction method according to claim 8 is the information reproduction method according to claim 7, wherein the reference light is a signal light modulated by a digital image representing a digital image of the document as a light and dark image, The first hologram and the second hologram are one hologram.

  The information reproducing apparatus according to claim 9, wherein document information is recorded as a first hologram due to interference between reflected object light and reference light of the document, and digital data representing the document digital data as a light and dark image An information reproducing apparatus for reproducing information of a document from a microfilm recorded as a second hologram by interference between signal light modulated by an image and reflected object light of the document, and a light source for emitting coherent light A branching unit for branching the coherent light emitted from the light source into two light waves, and an object light generating unit for irradiating the document with one of the light waves branched by the branching unit and generating reflected object light of the document And adjusting the optical path of the reflected object light generated by the object light generating means, and the reflected object light is applied to the second hologram recorded on the microfilm. Object light irradiating means for irradiating, adjusting the optical path of the other light wave branched by the branching means, and irradiating the light wave to the first hologram recorded on the microfilm; and And a light detection means for detecting transmitted light that has passed through the microfilm.

  The information reproducing apparatus according to claim 10, wherein document information is recorded as a hologram by interference between reflected object light of the document and signal light modulated by a digital image representing a digital image of the digital data of the document. An information reproducing apparatus for reproducing the information of the document from the microfilm, a light source for emitting coherent light, a branching unit for branching the coherent light emitted from the light source into two light waves, and a branching unit by the branching unit The object light generating means for irradiating the document with one of the light waves generated to generate the reflected object light of the document, and adjusting the optical path of the reflected object light generated by the object light generating means, The object data irradiating means for irradiating light onto the hologram recorded on the microfilm and a plurality of pixels are used to represent the digital data of the document as a light and dark image. A spatial light modulator that displays a digital image and modulates incident light for each pixel according to the displayed digital image, adjusts the optical path of the other light wave branched by the branching means, and Signal light generating means for generating signal light that is incident on the spatial light modulator and modulated in accordance with a digital image displayed on the spatial light modulator, and an optical path of the signal light generated by the signal light generating means And a signal light irradiating means for irradiating the hologram recorded on the microfilm with the signal light, and a light detecting means for detecting the transmitted light transmitted through the microfilm. And

  The invention according to each claim of the present invention has the following effects.

  According to the first aspect of the present invention, the document information having a large capacity is longer than the case of recording in an analog format without impairing the authenticity of the document (preventing tampering and ensuring evidence). In addition to being able to record and store over a period of time, the digital information of the document can be read out separately from the analog information of the document using the document, so that digital convenience can be enjoyed. That is, it is possible to achieve both “digital convenience” and “analog evidence”.

  According to the second aspect of the present invention, digital information and analog information of a document can be recorded with a single hologram, which makes it difficult to tamper with and increases the recording capacity of the microfilm. effective.

  According to the third aspect of the present invention, the digital information of the document is associated with the digital information and the analog information so that the digital information of the document can be read separately from the analog information of the document by using the document. There is an effect that it can be recorded on a film. As a result, tampering can be prevented to ensure evidence, and a large amount of document information can be recorded and stored over a long period of time compared to the case of recording in an analog format. Further, the digital information of the document can be read out separately from the analog information of the document by using the document, so that digital convenience can be enjoyed. That is, it is possible to achieve both “digital convenience” and “analog evidence”.

  According to the invention described in claim 4, the digital information of the document is associated with the digital information and the analog information so that the digital information of the document can be read separately from the analog information of the document by using the document. In addition to being able to record on a film, digital information and analog information of a document can be recorded with a single hologram. Thus, by recording digital information and analog information of a document with a single hologram, it becomes more difficult to tamper with and the recording capacity of the microfilm increases.

  According to the fifth aspect of the invention, it is possible to prevent tampering and ensure evidence, and record and store a large amount of document information over a long period of time as compared with the case of recording in an analog format. Further, since digital information of the document is recorded so that it can be read out separately from the analog information of the document using the document, digital convenience can be enjoyed. That is, it is possible to achieve both “digital convenience” and “analog evidence”.

  According to the invention described in claim 6, there are the effects that the alteration is further difficult and the recording capacity of the microfilm is increased.

  According to the invention described in claim 7, the digital information of the document is obtained from the microfilm recorded in the hologram format by associating the digital information and the analog information of the document with the analog information of the document using the document. Can be read separately, and there is an effect that digital convenience can be enjoyed. That is, it is possible to achieve both “digital convenience” and “analog evidence”.

  According to the eighth aspect of the invention, there is an effect that the digital information of the document and the analog information of the document can be read separately from one hologram recorded on the microfilm.

  According to the invention described in claim 9, the digital information of the document is obtained from the microfilm recorded in the hologram format in association with the digital information and the analog information of the document, and the analog information of the document is used with the document. Can be read separately, and there is an effect that digital convenience can be enjoyed. That is, it is possible to achieve both “digital convenience” and “analog evidence”.

  According to the tenth aspect of the invention, there is an effect that the digital information of the document and the analog information of the document can be read separately from one hologram recorded on the microfilm.

Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.
(Microfilm)
A microfilm is a photographic film for recording information such as a paper document by taking a reduced image. In order to take a reduced image, it has a higher resolution than a general photographic film, and can record a large amount of information in a smaller area. The microfilm includes at least a film-like support and a photosensitive recording layer formed on the support. In general, a transparent resin film such as triacetyl cellulose (TAC) or polyethylene terephthalate (PET) is used as the film-like support.

  Further, a photosensitive material for photographic film is usually used for the photosensitive recording layer. In the present invention, a hologram is recorded on a microfilm. Accordingly, the photosensitive material used for the photosensitive recording layer of the microfilm may be any photosensitive material as long as it can record a hologram, but a silver salt photosensitive material having excellent storage stability is preferable. A microfilm using a silver salt light-sensitive material such as a silver halide emulsion ensures long-term storage for 100 years or more.

  1A to 1C are diagrams showing various forms of microfilms. Microfilms are roughly classified into a roll-shaped roll film and a sheet-shaped sheet film. 1A and 1B are diagrams illustrating an example of a roll film, and FIG. 1C is a diagram illustrating an example of a microfish that is one form of a sheet film.

  As shown in FIG. 1A, the roll film 10 includes a band-shaped film 12. One end of the belt-like film 12 is fixed to the reel 14 and is wound around the reel 14. The other end 12A of the belt-like film 12 is an open end. As shown in FIG. 1B, on the film 12, a number of frames 16 that are recording areas are arranged along the length direction of the film. Each frame 16 is assigned a frame number 18 indicating the number of the frame.

In this example, six frames 16 _{1 to} 16 ₆ arranged from the other end 12A side of the film 12 are illustrated. Below the frames 16 _{1 to} 16 ₆ , frame numbers 18 ₁ to 18 ₆ are recorded. For example, the frame number 18 ₁ of the first frame 16 ₁ is "A01", the third frame 16 ₃ frame number 18 ₃ is "A03". After document information is recorded on the microfilm, the frame (area) 16 in which the document information is recorded is specified from the frame number 18.

  As shown in FIG. 1C, the microfish 20 includes a sheet-like film 12B. The sheet-like film 12B is a film having a rectangular shape in plan view. On the film 12B, a large number of frames 16 which are recording areas are arranged in a matrix. Each frame 16 is assigned a frame number 18 indicating the number of the frame. In the upper part of the film 12B, a heading column 22 for recording index information such as a title of a recorded document and a recorded date is arranged.

In this example, 15 frames 16 _{1 to} 16 ₁₅ are shown on the film 12B of the microfish 20. The 15 frames 16 _{1 to} 16 ₁₅ are arranged in a matrix of 3 rows and 5 columns. Below each of the frames 16 _{1 to} 16 ₁₅ , frame numbers 18 ₁ to 18 ₁₅ are recorded. For example, the frame number 18 ₁ of the first frame 16 ₁ is “A01”, and the frame number 18 _{15 of the fifteenth} frame 16 ₁₅ is “A15”. In the heading column 22, a heading “ABC... XYZ” is recorded.

  The roll film used as standard has a width of 16 mm and a length of 66 m. When document information is recorded on the roll film in an analog format, about 6000 documents can be recorded on one roll of film at a reduction ratio of 1/40. Also, the microfish used as standard is about A6 size, and there are 60 frames, 98 frames, 244 frames, and 270 frames.

FIG. 2 is a diagram showing the structure of the recording area of the microfilm. Here, the roll film 10 shown in FIG. 1 (A), illustrates the detailed structure of the frame 16 ₁ is a first-th recording region. Conventionally, a reduced image for one page is recorded in an analog format on one frame of microfilm. In the present invention, document information is recorded on a microfilm in a hologram format. When document information is recorded in the hologram format, the area of the recording area can be made smaller than in the case of recording in the analog format, and the recording capacity of the microfilm increases. If a Fresnel hologram that forms an image as it is is a Fourier transform hologram that is recorded by Fourier transform using a lens, the area of the recording area can be reduced by condensing the lens.

  Therefore, when document information is recorded in a hologram format, one frame can be divided into a plurality of sectors, and different document information can be recorded for each sector. One frame is divided into a plurality of sectors by an optically distinguishable method such as providing a partition line between adjacent sectors.

  When document information is recorded in a hologram format, document information of a plurality of documents can be multiplexed and recorded in one sector. For example, by changing the incident angle of the reference light for each document, a series of document groups can be angle-multiplexed and recorded at exactly the same place. Alternatively, shift multiplex recording can be performed in which the hologram of the next document is recorded so as to overlap the hologram of the previous document by moving the film slightly after recording the hologram for one document.

In this example, the frame 16 ₁ which is the first recording area of the film ₁₂ is divided into ₁₂ sectors 24 _{1 to} 24 ₁₂ by dotted lines. The twelve sectors 24 _{1 to} 24 ₁₂ are arranged in a matrix of 4 rows and 3 columns. For example, the document information of a plurality of documents can be multiplexed and recorded with holograms in the sector 24 _{8 in} the third row and the second column of the frame 16 ₁ (area displayed in white). As described above, multiplex recording methods such as angle multiplex recording and shift multiplex recording can be used.

  3A to 3C are diagrams showing an example of a format of a microfilm document. The format of microfilm documents has been standardized and standardized internationally by JIS, ISO, etc., in order to guarantee the legal evidence ability (evidence) equivalent to the original. For example, in the microfilm document handling rules established by the Japan Image Information Management Association, a “microfilm document” is a microfilm taken from an original document such as a paper document. It is defined as.

  Here, the “master film document” refers to a microfilm that retains legal proof ability and is stored by a manager in charge for the purpose of reproduction and copying of the film document to be stored and utilized. The “utilized film” refers to a microfilm that is a duplicate of a master film document and that is stored by a manager.

  In the above microfilm document handling rules, the format of the microfilm document is defined to include at least a document representing the beginning, a document representing the text, and a document representing the end. For example, when a microfilm document is completed with one roll film, as shown in FIG. 3A, a document 28 representing the beginning is arranged in front of a document 26 representing the text, and the document representing the text A document 30 representing the last is arranged after 26. By adopting such a format, the evidence of the microfilm document is guaranteed unless the film is cut and pasted.

  The document 28 representing the first includes a start display (open 0001) 28A, a resolution chart (microphotograph resolution test chart) 28B, an imaging request form (microphotographing request form) 28C, and a subject and contents 28D. . The document 30 representing the last includes each of a photographing certificate (microphotographing certificate) 30A, a resolution chart (microphotograph resolution test chart) 30B, and an end display (final) 30C. FIG. 3B is a diagram illustrating a specific example of the above-described photographing request slip 28C, and FIG. 3C is a diagram illustrating a specific example of the above-described photographing certificate 30A.

  Below, the information recording method and apparatus which record the information of each document contained in a series of document groups on a microfilm, and produce a microfilm document are demonstrated concretely. Information on each document is recorded on the microfilm in a hologram format obtained by interference of two light waves, not in an analog format in which an image of the document is reduced and recorded. In addition, below, the case where the roll film 10 is used is illustrated and paraphrased as the microfilm 10.

  A hologram is a recording of interference fringes of two light waves, and although it can be destroyed, it is difficult to intentionally tamper with it. In particular, it is impossible to intentionally alter a part of a hologram group recorded in a multiplexed manner (for example, a hologram corresponding to a specific document). Therefore, by recording document information on a microfilm in the form of a hologram, the capacity of the document is increased compared to the case of recording in an analog format without impairing the authenticity of the document (preventing tampering and ensuring evidence). It is possible to record and store the document information for a long time.

(Embodiment of the present invention)
In the embodiment of the present invention, as shown in FIG. 4, all of a series of document groups formatted for a microfilm document (a document 28 representing the first, a document 26 representing the body, and a document 30 representing the last). ) Will be described for each document in the same sector 24 of the microfilm 10 in the form of analog hologram and digital hologram. By recording on the microfilm in the hologram format, tampering can be prevented and evidence can be secured, and the recording capacity of the microfilm increases as compared with the case of recording in the analog format.

  An “analog hologram” is a hologram recorded by interference between reflected object light obtained by irradiating a document to be recorded with light and reference light. When an analog hologram is irradiated with the same reference light as that for recording as readout light, reflected object light is reproduced from the analog hologram. When the reproduced reflected object light is collected, an analog image of the recorded document is formed. That is, when recording is performed in the form of an analog hologram, “analog information of the document” is reproduced. In other words, the analog hologram is obtained by directly photographing and recording a hologram of a document, and it becomes easy to prevent tampering and secure evidence.

  On the other hand, the “digital hologram” is a hologram recorded by interference between signal light modulated with a digital image representing digital data of a document to be recorded as a light and dark image and reference light. When the digital hologram is irradiated with the same reference light as that for recording as readout light, signal light is reproduced from the digital hologram. When the reproduced signal light is collected, a digital image of the recorded document is formed. That is, when recorded in the form of a digital hologram, a digital image is reproduced. The digital image is decoded into digital data (document information of an electronic document). Accordingly, digital conveniences such as integrated management of document information, exchange / distribution of document information, effective use of document information, and searchability can be enjoyed.

  In this embodiment, the reflected object light obtained by irradiating the document to be recorded with light and the signal light modulated by the digital image representing the digital data of the document to be recorded as a light and dark image are caused to interfere with each other. A single hologram is recorded. This hologram is an analog hologram that reproduces reflected object light when irradiated with the same signal light as that used for recording as readout light. At the same time, signal light is reproduced when the same reflected object light as that used during recording is applied as readout light. It is also a digital hologram. That is, an analog hologram (first hologram) and a digital hologram (second hologram) are recorded as one hologram. When signal light is irradiated as readout light (readout reference light), the signal light is not reproduced from the hologram. Further, when the reflected object light is irradiated as readout light (readout reference light), the reflected object light is not reproduced from the hologram.

  In the present embodiment, as described above, with respect to one document (one page), the analog information and digital information of the document are recorded in association with one hologram, and the analog information and digital information are recorded from one hologram. Play information separately. In particular, when digital information is reproduced, it is possible to selectively reproduce only the digital information using a document (specifically, reflected object light obtained from the document). This makes it possible to achieve both “digital convenience” and “analog evidence”.

FIG. 5 is a schematic diagram showing the configuration of the information recording apparatus according to the first embodiment.
This information recording apparatus is provided with a light source 32 that oscillates laser light that is coherent light. As the light source 32, for example, a laser light source that oscillates green laser light having an oscillation wavelength of 532 nm is used. In addition, the information recording apparatus is provided with a control unit 58 that controls each unit of the information recording apparatus and a storage unit 60 that stores various data. The control unit 58 can be configured by, for example, a microcomputer provided with a CPU, a ROM, and a RAM. The storage unit 60 can be configured by a hard disk device (HDD) provided as an external storage device.

  The light source 32 is driven by a laser driving unit 62 connected to the control unit 58. On the light exit side of the light source 32, a half-wave plate 33 that changes the polarization direction of incident light and a polarization beam splitter 34 that reflects light having a predetermined polarization direction and transmits light having a polarization direction orthogonal thereto are arranged. Has been. A beam expander 36 that is an expansion / collimating optical system, a shutter 38 that can be inserted into or retracted from the optical path, and a pixel that is two-dimensionally arranged are incident on the light transmission side of the polarization beam splitter 34. A transmissive spatial light modulator 40 for intensity-modulating light is arranged in this order along the optical path from the polarization beam splitter 34 side. The shutter 38 is driven by a shutter driving unit 64 connected to the control unit 58 to open and close (moves in the direction of arrow C). Since the light quantity of the two light waves can be adjusted by the half-wave plate 33, the shutter 38 may be omitted.

  The spatial light modulator 40 is connected to the control unit 58 via a pattern generator (not shown). The pattern generator generates a two-dimensionally encoded pattern to be displayed on the spatial light modulator 40 according to the digital data supplied from the control unit 58. The spatial light modulator 40 modulates the incident laser light according to the display pattern to generate signal light. On the light transmission side of the spatial light modulator 40, a Fourier transform lens 42 that collects the signal light generated by the spatial light modulator 40 by Fourier transform is disposed.

  An image reading unit 66 including a scanner or the like that reads an image of a document held in the document holding unit 54 is provided in the vicinity of a document holding unit 54 described later. For example, the image reading unit 66 is provided on the upstream side of the document holding unit 54 with respect to the document conveyance direction so that the document reading unit 66 supplies the document after the image reading unit 66 reads the image of the document. Can do. The image reading unit 66 is connected to the control unit 58. The image data read by the image reading unit 66 is converted into digital data by the control unit 58, and the digital data of the document is stored in the storage unit 60. The digital data of the document is stored in the storage unit 60 in association with an identification code (for example, document ID, document ID, etc.) for identifying the document.

  The digital data of the document stored in the storage unit 60 is read by the control unit 58 and supplied to the pattern generator when generating the signal light. For example, when recording the hologram of the photographing certificate 30A shown in FIG. 3C, the display pattern (digital image) representing the digital data as a light and dark image from the digital data (document information of the document) of the photographing certificate 30A. 40A is generated, and the display pattern 40A is displayed on the spatial light modulator 40.

  A reflection mirror 46 is arranged on the light reflection side of the polarization beam splitter 34. On the light reflecting side (or light incident side) of the reflecting mirror 46, there are a wave plate 48, a shutter 50, and an magnifying / collimating optical system that give a predetermined optical path difference (phase difference) between linearly polarized light components having a specific wavelength orthogonal to each other. A certain beam expander 52 is arranged in this order along the optical path from the reflection mirror 46 side. The shutter 50 is driven to open and close by a shutter driving unit 64 connected to the control unit 58 (moves in the direction of arrow A). The shutter 50 may be omitted.

  On the light exit side of the beam expander 52, a document holding unit 54 that holds a document of an original document to be photographed such as a paper document is provided. Documents of the original document are conveyed one by one by a paper feeding mechanism (not shown) and are sequentially held in the document holding unit 54. The light emitted from the beam expander 52 is applied to the entire document (for example, the photographing certificate 30A shown in FIG. 3C) held in the document holding unit 54. Object light is reflected or scattered from the document held in the document holding unit 54 (reflected object light). On the exit side of the reflected object light, a Fourier transform lens 56 that collects the reflected object light is disposed.

Next, the recording operation of the information recording apparatus shown in FIG. 5 will be described.
When recording a hologram, the shutter 38 and the shutter 50 are opened, and laser light is emitted from the light source 32. The polarization direction of the laser light oscillated from the light source 32 is adjusted by the half-wave plate 33, enters the polarization beam splitter 34, and is branched. The light that has passed through the polarization beam splitter 34 is converted into large-diameter parallel light by a beam expander 36, passes through a shutter 38, and is applied to a spatial light modulator 40.

  The spatial light modulator 40 displays a display pattern in which the digital data of the document held in the document holding unit 54 is represented by a light and dark image. For example, when the photographing certificate 30A shown in FIG. 3C is held in the document holding unit 54, a display pattern (digital image) 40A representing the digital data of the photographing certificate 30A as a light and dark image is a space. It is displayed on the optical modulator 40. The display pattern is, for example, binary digital data “0, 1” expressed as “dark (black pixels), bright (white pixels)”.

  The light incident on the spatial light modulator 40 is intensity-modulated according to the display pattern, and signal light is generated. The signal light generated by intensity modulation by the spatial light modulator 40 is Fourier-transformed by the Fourier transform lens 42 and collected, and a predetermined position (for example, sector 24) of the microfilm 10 held by the film holding unit 44. Is irradiated. In the following, the predetermined position is described as sector 24.

  The light reflected by the polarization beam splitter 34 is reflected by the reflection mirror 46. The polarization direction of the light reflected by the reflection mirror 46 and having its optical path bent is adjusted by the wave plate 48. For example, the polarization direction of the light reflected by the polarization beam splitter 34 is orthogonal to the polarization direction of the light transmitted through the polarization beam splitter 34. However, in order to cause the two to interfere with each other, the polarization direction is caused by the wave plate 48. Are rotated by 90 ° so that the polarization directions are the same.

  The light transmitted through the wave plate 48 passes through the shutter 50, is converted into large-diameter parallel light by the beam expander 52, and is irradiated onto the entire document held in the document holding unit 54. Object light is reflected or scattered from the document held in the document holding unit 54 (reflected object light). The reflected object light is subjected to Fourier transform by the Fourier transform lens 56, collected, and applied to the sector 24 of the microfilm 10 held by the film holding unit 44.

  The reflected object light and the signal light are simultaneously applied to the sector 24. At the position where the reflected object light and the signal light are irradiated, interference fringes formed by the interference between the reflected object light and the signal light are recorded as a hologram.

  In the present embodiment, as described above, all of the series of documents (document 28 representing the beginning, document 26 representing the body, and document 30 representing the end) is photographed, and in the form of a hologram, Recording is sequentially performed on the same sector 24 one by one (see FIG. 4). Documents of the original document to be photographed are conveyed one by one by a paper feed mechanism (not shown) and sequentially held in the document holding unit 54, and a hologram is recorded by causing reflected object light and signal light to interfere with each document. To do. As described above, this hologram is not only an analog hologram from which reflected object light is reproduced, but also a digital hologram from which signal light is reproduced.

  In one hologram, document information of the same document is recorded as analog information as well as digital information. In other words, it is guaranteed that analog information and digital information reproduced from one hologram are document information of the same document. Therefore, even if the digital hologram is recorded based on the document information converted into digital data, it is associated with the analog image of the document. Therefore, from the readability of the analog image reproduced from the analog hologram , The evidence of digital data is ensured.

  Specifically, an analog image of a document reproduced from an analog hologram is readable by humans and is difficult to tamper with, similarly to an image of a document that is reduced and recorded in analog format on a microfilm. Further, since the digital data reproduced from the digital hologram is associated with the analog image of the document by the hologram, evidence is ensured.

  For different documents, the phase distribution of the interfering reflected object light and signal light is different for each document, so that holograms are multiplexed on the entire recording group in the same recording area (for example, sector 24) of the microfilm 10. Can be recorded.

  Next, with reference to FIGS. 6 and 7, an information reproducing method and an information reproducing apparatus for reading analog information and digital information from recorded holograms will be described. Analog information and digital information are mixed in one hologram on which document information of one document is recorded, but the analog information and digital information are reproduced separately.

  When reproducing digital information, as shown in FIG. 6, in addition to the configuration of the information recording apparatus described above (see FIG. 5), in order to detect the reproduced image from the digital hologram, On the transmission side, a Fourier transform lens 70 and a sensor array 72 composed of an image sensor such as a CCD or CMOS array are arranged. The sensor array 72 is connected to the control unit 58. Note that the same components as those of the information recording apparatus shown in FIG. In addition, in the configuration of the information recording apparatus shown in FIG.

  First, the shutter 38 is closed and the shutter 50 is opened, and laser light is emitted from the light source 32. The polarization direction of the laser light oscillated from the light source 32 is adjusted by the half-wave plate 33 and enters the polarization beam splitter 34. If there is light that has passed through the polarization beam splitter 34, it passes through the beam expander 36 and is blocked by the shutter 38. On the other hand, the light reflected by the polarization beam splitter 34 is reflected by the reflection mirror 46 as in the recording. The light reflected from the reflection mirror 46 and having its optical path bent is adjusted by the wave plate 48 in light intensity and polarization direction.

  The light transmitted through the wave plate 48 passes through the shutter 50, is converted into large-diameter parallel light by the beam expander 52, and is irradiated onto the entire document held in the document holding unit 54. Object light is reflected or scattered from the document held in the document holding unit 54 (reflected object light). The reflected object light is Fourier-transformed by the Fourier transform lens 56 and condensed, and is irradiated onto the sector 24 of the microfilm 10 held by the film holding unit 44 as reference light for reading.

  The irradiated read reference light (reflected object light) is diffracted by the recorded hologram when passing through the recording area of the microfilm 10 to generate transmitted diffracted light. The transmitted diffracted light generated from the digital hologram is emitted to the Fourier transform lens 70 side. The transmitted diffracted light is subjected to inverse Fourier transform by the Fourier transform lens 70 to reproduce the signal light, and the reproduced signal light enters the sensor array 72. On the surface of the sensor array 72, the signal light is collected and a digital image of the document is formed.

  For example, when the photographing certificate 30A shown in FIG. 3C is used, a display pattern (digital image) 40A representing the digital data of the photographing certificate 30A as a bright and dark image is formed on the surface of the sensor array 72. Imaged. As a result, a digital image of the document is captured. In this way, only the digital information can be selectively reproduced using the reflected object light obtained from the document.

  The sensor array 72 converts the received light into an electrical signal and outputs it. The sensor array 72 captures a digital image formed on the light receiving surface and outputs image data of the captured digital image to the control unit 58. The control unit 58 decodes the digital data based on the image data. The decrypted digital data can be stored in the storage unit 60, for example, and can be read out and used as appropriate. In addition, keyword search and printout can be performed using digital data.

  Further, as already described, since the digital data reproduced from the digital hologram is guaranteed evidence, the digital data stored in the storage unit 60 is converted into the digital hologram for one document identified by the identification code or the like. It is also possible to prove the evidence of the stored digital data by collating with the digital data reproduced from In other words, it is possible to confirm whether or not the stored digital data has been tampered with by reproducing the digital data recorded on the hologram using the reflected object light obtained from the real document (original document). Can do.

  When reproducing analog information, as shown in FIG. 7, in addition to the configuration of the information recording apparatus described above (see FIG. 5), in order to detect the reproduced image from the digital hologram, the light of the microfilm 10 is used. On the transmission side, a Fourier transform lens 74 and a sensor array 76 composed of an image sensor such as a CCD or CMOS array are arranged. The sensor array 76 is connected to the control unit 58. Note that the same components as those of the information recording apparatus shown in FIG. In addition, in the configuration of the information recording apparatus shown in FIG.

  First, the shutter 50 is closed and the shutter 38 is opened, and laser light is emitted from the light source 32. The polarization direction of the laser light oscillated from the light source 32 is adjusted by the half-wave plate 33 and enters the polarization beam splitter 34. If there is light reflected by the polarization beam splitter 34, it is reflected by the reflection mirror 46, passes through the wave plate 48, and then blocked by the shutter 50.

  The light that has passed through the polarization beam splitter 34 is converted into large-diameter parallel light by a beam expander 36, passes through a shutter 38, and is applied to a spatial light modulator 40. The spatial light modulator 40 displays a display pattern in which digital data of “a document for which analog information is to be reproduced” is represented by a light and dark image. Since the digital data of the document is identified by an identification code or the like and stored in the storage unit 60, the digital data of the document to be reproduced is read from the identification code and a display pattern is generated. For example, when it is desired to reproduce the analog information (analog image) of the photographic certificate 30A shown in FIG. 3C, a display pattern (digital image) 40A representing the digital data of the photographic certificate 30A as a light and dark image is displayed in a space. Displayed on the optical modulator 40.

  The light incident on the spatial light modulator 40 is intensity-modulated according to the display pattern, and signal light is generated. The signal light generated by intensity modulation by the spatial light modulator 40 is Fourier-transformed by the Fourier transform lens 42 and condensed, and is read to the sector 24 of the microfilm 10 held by the film holding unit 44. Irradiated as light.

  The irradiated read reference light (signal light) is diffracted by the recorded hologram when passing through the recording area of the microfilm 10 to generate transmitted diffracted light. The transmitted diffracted light generated from the analog hologram is emitted to the Fourier transform lens 74 side. The transmitted diffracted light is subjected to inverse Fourier transform by the Fourier transform lens 74 to reproduce the reflected object light, and the reproduced reflected object light is incident on the sensor array 76. Reflected object light is collected on the surface of the sensor array 76, and an analog image of the document is formed. As a result, an analog image of the document is captured. The sensor array 76 outputs an electrical signal representing the captured analog image to the control unit 58.

  In addition, as already described, the analog hologram is, as it were, recorded by directly photographing a hologram of a document, and the analog image reproduced from the analog hologram has legibility. Therefore, recording in the form of an analog hologram makes it easy to prevent document tampering and ensure evidence.

  In the above embodiment, an example in which one document is recorded by one hologram (analog hologram and digital hologram) has been described. However, one document has two holograms (analog hologram and digital hologram). May be recorded. In this case, as shown in FIG. 8, an analog hologram is recorded by causing interference between reflected object light obtained by irradiating the document to be recorded with light and reference light having a wavefront different from the signal light. Then, the digital hologram is recorded by causing interference between the reflected object light obtained by irradiating the document to be recorded with light and the signal light modulated by the digital image representing the digital data of the document to be recorded as a light and dark image. .

  When the analog hologram is irradiated with the same reference light as the recording light as the readout light, the reflected object light is reproduced. Further, when a digital hologram is irradiated with the same reflected object light as that during recording as readout light, signal light is reproduced. When the reflected object light is irradiated as read light (read reference light), the reflected object light is not reproduced from the digital hologram.

  For one document (one page), the analog information and digital information of this document are related by one document (specifically, reflected object light obtained from the document) and recorded as two holograms. Analog information and digital information are reproduced separately from the two holograms. When digital information is reproduced, only digital information can be selectively reproduced using a document (reflective object light obtained from the document), and the evidence of the reproduced digital information can be guaranteed. It is the same as the form. This makes it possible to achieve both “digital convenience” and “analog evidence” as in the above-described embodiment.

  In the above embodiment, all of the series of documents (the document 28 representing the first, the document 26 representing the main body, and the document 30 representing the last) are multiplexed on the same sector 24 of the microfilm 10 in the form of a hologram. Although an example of recording has been described, a part of a series of documents (document 28 representing the first and document 30 representing the last) is recorded on the microfilm 10 in an analog format as usual, and only the document 26 representing the text is recorded. Multiple recording can be performed in a hologram format in a recording area between the frame of the document 28 representing the first and the frame representing the document 30 representing the last. In this case, tampering is further difficult from the viewpoint of readability.

(A)-(C) are figures which show the various forms of a microfilm. It is a figure which shows the structure of the recording area of a microfilm. (A)-(C) are figures which show an example of the format of a microfilm document. It is a conceptual diagram for demonstrating an example of the information recording method which concerns on embodiment of this invention. It is the schematic which shows the structure of the information recording device which concerns on embodiment of this invention. It is a figure explaining the apparatus and method of reproducing | regenerating digital information from the hologram recorded with the information recording method which concerns on this Embodiment. It is a figure explaining the apparatus and method of reproducing | regenerating analog information from the hologram recorded with the information recording method which concerns on this Embodiment. It is a conceptual diagram for demonstrating another example of the information recording method which concerns on embodiment of this invention.

Explanation of symbols

10 Microfilm (roll film)
12 Film 12B Film 14 Reel 16 Frame 18 Frame number 20 Microfiche 22 Heading column 24 Sector 26 Document representing the body 28 Document representing the beginning 28C Photographing request form 30 Document representing the end 30A Photographing certificate 32 Light source (laser)
33 Half-wave plate 34 Polarizing beam splitter 36 Beam expander 38 Shutter 40 Spatial light modulator 40A Display pattern (digital image)
42 Fourier transform lens 44 Film holding unit 46 Reflecting mirror 48 Wave plate 50 Shutter 52 Beam expander 54 Document holding unit 56 Fourier transform lens 58 Control unit 60 Storage unit 62 Laser drive unit 64 Shutter drive unit 66 Image reading unit 70 Fourier transform lens 72 sensor array 74 Fourier transform lens 76 sensor array

Claims (10)

  The document information is recorded on the microfilm as a first hologram by interference between the reflected object light of the document and the reference light, and the signal light modulated by the digital image representing the digital data of the document as a light and dark image An information recording method comprising: recording on the microfilm as a second hologram by interference with reflected object light of a document.   The reference light is signal light modulated by a digital image representing digital data of the document as a light and dark image, and the first hologram and the second hologram are one hologram. The information recording method according to claim 1. A light source that emits coherent light;
Branching means for branching the coherent light emitted from the light source into two light waves;
An object light generating means for irradiating a document with one of the light waves branched by the branching means and generating a reflected object light of the document;
Adjusting the optical path of the reflected object light generated by the object light generating means, and irradiating the reflected object light to the microfilm;
Adjusting the optical path of the other light wave branched by the branching means, and irradiating the light wave to the position where the reflected object light of the microfilm is irradiated simultaneously with the reflected object light; and
A spatial light modulator that displays a digital image representing the digital data of the document as a light and dark image using a plurality of pixels and modulates incident light for each pixel according to the displayed digital image, and includes the branching unit. Signal light that adjusts the optical path of the other branched light wave, causes the light wave to enter the spatial light modulator, and modulates according to the digital image displayed on the spatial light modulator to generate signal light Generating means;
A signal light irradiating unit that adjusts the optical path of the signal light generated by the signal light generating unit and irradiates the signal light to the position of the microfilm on which the reflected object light is irradiated simultaneously with the reflected object light. When,
An information recording apparatus comprising: A light source that emits coherent light;
Branching means for branching the coherent light emitted from the light source into two light waves;
An object light generating means for irradiating a document with one of the light waves branched by the branching means and generating a reflected object light of the document;
Adjusting the optical path of the reflected object light generated by the object light generating means, and irradiating the object light to the microfilm;
A spatial light modulator that displays a digital image representing the digital data of the document as a light and dark image using a plurality of pixels and modulates incident light for each pixel according to the displayed digital image, and includes the branching unit. Signal light that adjusts the optical path of the other branched light wave, causes the light wave to enter the spatial light modulator, and modulates according to the digital image displayed on the spatial light modulator to generate signal light Generating means;
A signal light irradiating unit that adjusts the optical path of the signal light generated by the signal light generating unit and irradiates the signal light to the position where the reflected object light of the microfilm is irradiated simultaneously with the reflected object light. When,
An information recording apparatus comprising:   Document information is recorded as a first hologram by the interference between the reflected object light of the document and the reference light, and the signal light modulated by the digital image representing the digital data of the document as a light and dark image and the document light A microfilm recorded as a second hologram by interference with reflected object light.   The reference light is signal light modulated by a digital image representing digital data of the document as a light and dark image, and the first hologram and the second hologram are one hologram. The microfilm according to claim 5. Document information is recorded as a first hologram by the interference between the reflected object light of the document and the reference light, and the signal light modulated by the digital image representing the digital data of the document as a light and dark image and the document light An information reproducing method for reproducing document information from a microfilm recorded as a second hologram by interference with reflected object light,
The first hologram is irradiated with the reference light to reproduce an analog image of the document, and the second hologram is irradiated with a reflected object light of the document to generate a digital image of the document or digital data corresponding to the digital image. A method for reproducing information, characterized by comprising:   The reference light is signal light modulated by a digital image representing digital data of the document as a light and dark image, and the first hologram and the second hologram are one hologram. The information reproduction method according to claim 7. Document information is recorded as a first hologram by the interference between the reflected object light of the document and the reference light, and the signal light modulated by the digital image representing the digital data of the document as a light and dark image and the document light An information reproducing apparatus for reproducing information of the document from a microfilm recorded as a second hologram by interference with reflected object light,
A light source that emits coherent light;
Branching means for branching the coherent light emitted from the light source into two light waves;
An object light generating means for irradiating a document with one of the light waves branched by the branching means and generating a reflected object light of the document;
Adjusting the optical path of the reflected object light generated by the object light generating means, and irradiating the second hologram recorded on the microfilm with the reflected object light; and
Adjusting the optical path of the other light wave branched by the branching means, and irradiating the first hologram recorded on the microfilm with the light wave; and
A light detecting means for detecting transmitted light transmitted through the microfilm;
An information reproducing apparatus comprising: The document information is reproduced from the microfilm recorded as a hologram by the interference between the reflected object light of the document and the signal light modulated by the digital image representing the digital data of the document as a light and dark image. An information reproducing apparatus that
A light source that emits coherent light;
Branching means for branching the coherent light emitted from the light source into two light waves;
An object light generating means for irradiating a document with one of the light waves branched by the branching means and generating a reflected object light of the document;
Adjusting the optical path of the reflected object light generated by the object light generating means, and irradiating the reflected object light on the hologram recorded on the microfilm; and
A spatial light modulator that displays a digital image representing the digital data of the document as a light and dark image using a plurality of pixels and modulates incident light for each pixel according to the displayed digital image, and includes the branching unit. Signal light that adjusts the optical path of the other branched light wave, causes the light wave to enter the spatial light modulator, and modulates according to the digital image displayed on the spatial light modulator to generate signal light Generating means;
Adjusting the optical path of the signal light generated by the signal light generating means, and irradiating the signal light to the hologram recorded on the microfilm; and
A light detecting means for detecting transmitted light transmitted through the microfilm;
An information reproducing apparatus comprising:

Images