JPH0436756A - Recording medium for plural sets of information and recording method - Google Patents

Abstract

PURPOSE:To allow efficient recording and reproducing of the main information of videos, etc., and the sub-information of voices, etc., with simple constitution by providing a frequency sepn. filter only in the main information recording part of the recording medium which records the main information and sub-information. CONSTITUTION:The recording medium 1 is provided with the color sepn. filter (frequency sepn. filter) 19 in the region MR where the main information in images, etc., is recorded. This color sepn. filter is not provided in the region where the sub-information SR, such as voice or retrieval information, is recorded. The recording medium 1 and a recording head 20 are so disposed that a charge holding layer 12 and a photoconductive layer 22 face each other at a prescribed spacing. The optical image of a subject is made incident from the glass base 18 side of the recording medium 1 as shown by an arrow F1. The main information, such as color image, is efficiently subjected to color sepn. and color multiplexing with the simple constitution so that the color images, etc., can be easily recorded. On the other hand, the sub-information recording region SR is a transparent part S where there are no filters and, therefore, the use of light of an arbitrary wavelength region as writing light is possible. A laser device of a single wavelength is used as a light source and an optical deflector of a simple type is utilizable as well.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a recording medium and a recording method for recording and reproducing information using electromagnetic radiation using a frequency-resolving filter, and particularly relates to a recording medium and a recording method for recording and reproducing information using electromagnetic radiation using a frequency-resolving filter. The present invention relates to a recording medium and a recording method for a plurality of information that can efficiently record and reproduce sub-information such as, etc., with a simple configuration.

(Prior Art) A medium and a recording/reproducing device for recording and reproducing information using electromagnetic radiation using a frequency separation filter (color separation filter) are disclosed in Japanese Patent Application No. 1-128, which was already invented by the applicant company.
There is one described in the specification of No. 069.

Hereinafter, a part thereof will be quoted from the above specification and explained with reference to FIGS. 4(A) and 4(B).

First, the recording system will be explained with reference to FIG. 4(A).

In the figure, a recording medium 10 on which a charge latent image is formed is
Charge retention layer 12. Transparent electrode 149 Color separation filter 6
and glass base 18 are laminated in this order. On the other hand, the recording head 20 has a photoconductive layer 22
．． The electrode layer 24 and the base material 26 are laminated in this order.

The recording medium 10 and the recording head 20 are arranged such that the charge retention layer 12 and the photoconductive layer 22 face each other at a predetermined interval. Imaging lens as shown (not shown)
It is designed to enter through.

Further, a power source 32 is connected between the transparent electrode 14 and the electrode layer 24, so that discharge occurs between the charge retention layer 12 and the photoconductive layer 22.

Among the above parts, the color separation filter layer 16 is red (R).
The configuration is such that minute bar-shaped filters 16R, 16G, and 16B are arranged in order to transmit light of the three primary colors of , green (G), and blue (B), respectively.

Next, the operation of the recording system configured as described above will be explained. The optical image of the object enters from the right side of the figure as indicated by arrow F1, passes through the recording medium 10, and enters the recording head 2.
0 to the photoconductive layer 22.

At this time, the light passes through the filter 16R of the color separation filter layer 16.
, 16G, and 16B, the light is separated into the three primary colors of R, G, and B. That is, only the R component of the incident light passes through the filter 16R, only the G component of the incident light passes through the filter 16G, and only the B component of the incident light passes through the filter 16B. These color-separated transmitted lights are transmitted to the transparent electrode 14. The light passes through the charge retention layer 12 and enters the photoconductive layer 22.

Next, within this photoconductive layer 22, the impedance of that portion changes depending on the intensity of the incident light, the incident light is absorbed, and electron-hole pairs are generated. However, as described above, the voltage of the power source 32 is applied between the transparent electrode 14 and the electrode layer 24.

Therefore, electrons in the photoconductive layer 22 are attracted by the positive polarity of the power source 32 and move toward the electrode layer 24, and holes move toward the surface of the photoconductive layer 22 facing the charge retention layer. As a result, a hole image or a positive charge image corresponding to an optical image of the subject 28 is formed on the surface of the photoconductive layer 22. Since such an operation is performed for each of the R, G, and B separated lights, a positive charge image is formed for each separated light.

Furthermore, by applying the voltage from the power source 32, the charge retention layer 12
A discharge occurs between the opposite surfaces of the photoconductive layer 22 and the opposite surfaces of the photoconductive layer 22. This discharge charges the surface of the charge retention layer 12, and charges are accumulated and retained on the surface.

In this case, the degree of charging due to discharge is determined according to the hole distribution on the surface of the photoconductive layer 22, that is, the positive charge image. Therefore, a charge image corresponding to the optical image of the subject 28 is transferred onto the surface of the charge retention layer 12. That is, the recording head 20 records an optical image of the subject 28 on the surface of the recording medium 10 as a latent charge image. Note that since a positive charge image on the surface of the photoconductive layer 22 is formed for each separated light, a charge latent image on the recording medium 10 is also formed for each separated R, G, and B light.

Next, the reproduction system will be explained with reference to FIG. 4(B). In the figure, a reproducing head 34 is disposed to face the recording medium 10 on which a latent charge image has been formed.

The reproducing head 34 is composed of a light modulation layer 36 and a transparent electrode 38, and the surface side of the light modulation layer 36 faces the charge retention layer 12 of the recording medium 10. Then, read light shown by arrow F2 is made incident from the recording medium 10 in the direction of the reproducing head 34. As this readout light, white light or light obtained by multiplexing R, G, and H separated light components is used.

Further, the readout light transmitted through the reproducing head 34 is
3. Dichroic filter 40 as shown respectively at F4
．． 42, respectively. Among these, the dichroic filter 40 is configured to transmit the G component of the incident light.
2 is configured to transmit the B component in the incident light.

Next, the operation of the reproduction system as described above will be explained. As explained with reference to FIG. 4(A), a charge latent image of the subject 28 is formed on the recording medium 10. The reproducing head 34 is placed close to the recording medium 10, and transparent electrodes 14, 38 are electrically connected thereto. Then, the electric field of the latent image charge on the surface of the charge retention layer 12 comes to influence the light modulation layer 36, resulting in an electro-optic effect on the incident light.

When the readout light enters the recording medium 10 in this state as shown by the arrow F2, the readout light is subjected to color separation into R, G, and B by the color separation filter 16, similar to the recording system described above. As a result, the decomposed lights R, G, and B pass through the filters 16R, 16G, and 16B, respectively, and enter the reproducing head 34.

When these decomposed lights R, G, and B enter the reproducing head 34, electro-optic effects are generated by the light modulation layer 36, respectively. For example, the phase difference between normal light and extraordinary light passing through the light modulation layer 36 changes depending on the degree of the electric field applied by the latent image charge Q.

The read light subjected to the electro-optic effect passes through the reproducing head 34 and enters the dichroic filter 40 as shown by arrow F3. Only the decomposed light G passes through this as shown by arrow F5, and the remaining R and B components enter the next dichroic mirror 42 as shown by arrow F4. and,
Here, the decomposed light R is reflected as shown by arrow F6, and the decomposed light B
passes through the dichroic filter 42 as shown by arrow F7. In this way, the dichroic filter 40.
By the action of 42, the readout light subjected to the electro-optic effect is decomposed into its R, G, and B components.

In the above operation, among the latent image charges recorded on the recording medium 10, the filter 16R of the color separation filter layer 16
What is generated by the light transmitted through the filter 16R is generated by the light modulating layer 3 for the decomposed light R transmitted through the filter 16R during reproduction.
6 acts to produce an electro-optic effect. Therefore, the optical image R of the subject 28 is reproduced by the separated light R reflected by the dichroic filter 42 in the direction of the arrow F6. The same applies to G and B.

That is, the filters 16R, 1 of the color separation filter layer 16
Due to the action of 6G and 16B, R, G,
Charge images of B are respectively formed.

Light modulation in the light modulation layer 36 by the electric field of these charge images is performed by filters 16R and 16G.

Decomposed lights R and G generated by the action of 16B.

Each occurs for B. Therefore, these decomposed lights R, G
, B, a color-separated image of the optical image of the subject 28 is reproduced.

On the other hand, as a device for recording and reproducing multiple information such as main information (images) and sub information (audio), there is a device already invented by the applicant's company and described in the specification filed on April 2, 1990. (Title of the invention: "Recording and reproducing device for multiple information").

Hereinafter, a part thereof will be quoted from the above specification and explained with reference to FIGS. 5(A) and 5(B).

In the recording system shown in FIG. 5(A), RM is an information recording medium, and BPI is a transparent substrate (for example, a glass substrate).
, BF2 is the substrate, ti is the transparent electrode, t2 is the electrode, P
CL is a photoconductive layer member, CML is a recording layer member in the information recording medium RM, and E is a power source.

SW is a switch (voltage shutter), R is a resistor, and WH is a write head.

Here, the principle of recording main information (image information) on the information recording medium RM will be explained as follows. When the switch SW is turned on and a predetermined voltage is applied from the power source E between the transparent electrode E and the electrode Et2, the recording target imaged on the photoconductive layer member PCL is Recording corresponding to the electromagnetic radiation (for example, an optical image of a subject) having information carried out is performed on the recording layer member of the information recording medium RM. In other words, when a light beam from a subject passes through the transparent electrode Et and is incident on the photoconductive layer member PCL to form an image, the electrical resistance value of the photoconductive layer member PCL will depend on the amount of light that is incident on it and formed an image. As a result, the electric resistance value of each part of the photoconductive member PCL is changed in accordance with the amount of light of each part of the subject. When the electrical resistance value of each part of the photoconductive layer member PCL changes in response to the luminous flux from the subject described above, the surface of the photoconductive layer member PCL on which the transparent electrodes E and 1 are not provided will receive the aforementioned light. A distribution of the amount of charge occurs in accordance with the change in the electrical resistance value of each part of the conductive layer member PCL, and an electric field corresponding to the distribution of the amount of charge (charge image) generated in the photoconductive layer member PCL is generated in the photoconductive layer member PCL. It is applied to the recording medium RM which is placed opposite to the PCL. The recording medium RM, which is given an electric field generated in a charge image due to the information being recorded, changes its optical properties such as the state of light scattering, the state of birefringence, and the state of optical rotation by applying a voltage. Then, the intensity distribution of the applied electric field is memorized as a form of change in optical properties, and when light with a certain intensity distribution is given to it, it is possible to generate light that shows an intensity distribution according to the above-mentioned stored contents. This will cause this to occur.

Based on the above principle, image information is recorded in the image information recording area MR of the information recording medium RM.

Further, sub information (audio information) is also recorded using the same principle.

In the recording system shown in the figure, an electrical signal generated from an audio signal generator 41 such as a microphone is amplified by an amplifier 42 and then supplied to a light source LS that emits incoherent light.

The light source LS described above emits incoherent light whose intensity is modulated according to the audio information to be recorded, and supplies it to the optical deflector 43. In the optical deflector 43, the incoherent light whose intensity is modulated by the audio information to be recorded is applied to the audio information recording area SR of the information recording medium RM and recorded as audio information. It is deflected in a predetermined deflection manner and made incident on the write head WH.

FIG. 5(B) shows a reproduction system from a recorded recording medium RM.

Image information readout light RLv is applied to the image information recording area MR, and the light emitted from the recorded information recording medium RM is applied to the line message sensor LIS to scan the line image sensor LIS in the sub-scanning direction to generate an image signal. After the image signal generated and output from the line image sensor LIS is subjected to predetermined signal processing in a signal processing circuit 44, it is supplied to an image output device 45 to obtain an image output.

Also, the audio information readout light RL emitted from the light source LS
A is deflected in the horizontal direction by the optical deflector 3 to sub-scan the audio information recording area SR on the recorded information recording medium RM. The read light that has passed through the recorded information recording medium RM is focused by a focusing optical system 47 and given to the photoelectric converter PD. Photoelectric converter PD mentioned above
The audio signal output from the demodulator 48 is demodulated by the demodulator 48, amplified by the amplifier 49, and output from the speaker as an audio signal. Note that the recorded information recording medium RM described above is configured to be moved in a direction perpendicular to the sub-scanning direction described above.

(Problems to be Solved by the Invention) A device that records and reproduces information using electromagnetic radiation using the frequency (color) separation filter detailed in FIGS. 4 (A) and (B) is suitable for recording color images. On the other hand, it is extremely unsuitable for recording side information such as voice and search information. That is, as detailed in FIGS. 5A and 5B, when an audio signal is optically modulated and written, it is necessary to use light that includes all of the R, G, and B parts. If a simple light source such as a single wavelength laser device is used, the frequency (color) separation filter limits the frequency of the writing light before it reaches the recording medium, resulting in a significant drop in recording density.

Furthermore, it is not easy to efficiently record and reproduce a large amount of sub-information such as a single voice character or a search signal using a simple device.

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a recording medium that includes at least a frequency decomposition filter and an information recording layer, and records main information and sub information. A plurality of information recording medium is provided in which the frequency decomposition filter is provided only in the information recording section, and main information and sub information are recorded together on the recording medium including at least the frequency decomposition filter and the information recording layer. A recording method that records multiple pieces of sub-information,
The present invention provides a method for recording a plurality of information in a multiplexed manner using a plurality of electromagnetic radiation fluxes in a wavelength range corresponding to the frequency resolution filter.

(Operation) In the multiple information recording medium configured as described above, only the main information is frequency-resolved by the frequency-resolving filter and recorded. Furthermore, in the method for recording multiple pieces of information configured as described above, multiple pieces of sub-information are multiplexed and recorded using multiple electromagnetic radiation fluxes using a frequency resolution filter.

(Example) An example of the recording medium and recording method for multiple pieces of information according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view showing a recording medium for multiple pieces of information, and FIG. 2 is an explanatory diagram showing a method for recording multiple pieces of information.

First, a recording medium for multiple pieces of information will be explained with reference to FIG. This recording medium is designed so that a color separation filter (frequency separation filter) is provided in the area where main information such as images is recorded, and no color separation filter is provided in the area where sub information such as voice and search information is recorded. This is what I did.

In the figure, a recording medium 1 on which a latent charge image is formed has a charge retention layer 12 . The transparent electrode 141, the color separation filter 9, and the glass base 18 are laminated in this order. On the other hand, the recording head 20 has a photoconductive layer 22 .
The electrode layer 24 and the base material 26 are laminated in this order.

The recording medium 1 and the recording head 20 are arranged so that the charge retention layer 12 and the photoconductive layer 22 face each other at a predetermined interval, and the optical image of the subject is shown in the direction of the arrow F1 from the glass base 18 side of the recording medium 1. As shown, the light enters through an imaging lens (not shown).

Further, a power source 32 is provided between the transparent electrode 14 and the electrode layer 24.
are connected so that a discharge occurs between the charge retention layer 12 and the photoconductive layer 22.

Among the above parts, the color separation filter layer 19 is red (R).
, green (G), and blue (B), respectively, and a transparent portion S. There is. The main information recording area MR where main information such as a color image is recorded, for example, the upper side of the recording medium 1, is
The sub-information recording area SR1 in which sub-information such as voice and search information is recorded serves as the above-described filter portion F, and the lower side of the recording medium 1, for example, serves as the above-described transparent portion S.

With respect to the recording medium 1 configured as described above, main information such as color images, audio, search information, etc. are stored using the recording and reproducing method shown in FIGS. The sub information is recorded and reproduced.

In the recording medium 1, the main information recording area MR in which main information such as color images is recorded is a filter section F, so color separation and color multiplexing can be performed efficiently with a simple configuration, and color images etc. can be recorded. can be easily done. On the other hand, since the sub information recording area SR where sub information such as voice and search information is recorded is a transparent part S without any filter, it is possible to use light in any wavelength range as the writing light, and the light source A single wavelength laser device or the like can be used as a laser device. Therefore, a simple light source and optical deflector for recording and reproducing sub-information can be used.

Note that in the recording medium 1 shown in FIG. 1, an example has been described in which the photoconductive layer 22 is a separate body as the recording head 20; You may.

In addition, in the embodiment, the recording layer members of the recording medium 1 include:
A charge retention material was used that has the ability to retain a charge image corresponding to the information being recorded for a long period of time, but the state of light scattering and
A light modulating material whose optical properties such as the state of sub-refraction and the state of optical rotation change may be used.

Next, a method for recording multiple pieces of information will be described with reference to FIGS. 2 and 3. This recording method has already been used in Figure 4 (A
) and (B), a large amount of sub-information such as voice information and search information can be multiplexed and recorded on the recording medium 1o having color separation filters on the entire surface.

The left side of the recording medium 10 shown in FIG. 2 is an area MR for recording main information such as a color image, and the main information is recorded here by the method already described in detail. Further, the right side of the recording medium 10 is an area SR for recording a plurality of sub-information, and a plurality of multiplexed sub-information is recorded here.

Next, multiplexing of a plurality of sub information will be explained.

Reference numerals 50, 51, and 52 denote a group of circuits in which sub-information is generated; for example, 50 is a right channel audio generation circuit, 51 is a left channel audio generation circuit, and 52 is a search information generation circuit. The outputs of the sub-information generating circuits 50, 51, 52 are input to optical modulators 5B, 54, 55, respectively, and modulated light whose intensity is modulated according to the sub-information to be recorded is output. The three modulated lights are sent to the next stage dichroic mirror group 56.
The three colors are optically synthesized.

As shown in FIG. 3, in the dichroic mirror group 56, only the G color light is separated and detected by the incident transmitted light from the light modulator 53 to the surface 56G, and the R color light is detected by the incident reflected light from the light modulator 54 to the surface 56R. Only the B color light is separated and detected by the incident and reflected light from the light modulator 55 to the surface 56B.

The lights separated and detected as R color light, G color light, and B color light are combined into three colors by the reflective surface of surface 56G. As a result, the right channel audio is recorded as G color light, the left channel audio is recorded as R color light, and the search information is recorded as B color light. In other words, a plurality of sub-information is frequency-multiplexed on the writing light that has been synthesized in three colors by the dichroic mirror group 56.

The writing light is applied to a recording area S of predetermined sub information using an optical deflector 57.
The sub information is scanned and deflected within R, and the multiplexed sub information is recorded on the recording medium 10.

During reproduction, the reflected light that has passed through the sub-information recording area SR is incident on the dichroic mirror group 56 from the opposite direction to that during recording, and after being separated into three colors, each is photoelectrically converted by a light receiving element to generate electricity. It is sufficient to detect it as a signal and demodulate it.

In this way, since multiple pieces of sub-information are recorded and reproduced by color multiplexing (frequency multiplexing), an information recording medium that records information using electromagnetic radiation (e.g. light) using a color (frequency) separation filter over the entire surface. 10, a plurality of sub-information can be efficiently recorded using a simple recording/reproducing device.

(Effects of the Invention) According to the multiple information recording medium of the present invention, the main information recording area in which main information such as a color image is recorded is a frequency separation filter. Color) multiplexing can be done efficiently with a simple configuration, making it easy to record color images, etc. On the other hand, the sub-information recording area where sub-information such as voice and search information is recorded is a transparent area without any frequency resolution filter. Therefore, it is possible to use light in any wavelength range as the writing light, and a single wavelength laser device or the like can be used as the light source. Therefore, a simple light source and optical deflector for recording and reproducing sub-information can be used.

Furthermore, according to the method for recording multiple pieces of information according to the present invention, multiple pieces of sub information are recorded and reproduced by frequency (color) multiplexing. ) can also efficiently record a plurality of pieces of sub-information using a simple recording and reproducing device.

As described above, according to the recording medium and method for recording multiple information according to the present invention, main information such as a color image and sub information such as audio and search signals can be efficiently recorded and reproduced using a simple device. be able to.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of a recording medium for multiple information according to the present invention, FIG. 2 is an explanatory diagram for explaining an embodiment of a recording method for multiple information according to the present invention, and FIG. is a diagram showing an example of the configuration of a dichroic mirror group that performs color synthesis and color separation, FIGS. 4(A) and (B) are diagrams explaining a conventional recording medium, and FIGS. 5(A) and (B) are FIG. 2 is a diagram illustrating a conventional recording and reproducing method. 1... Recording medium, 12... Charge retention layer, one...
Color separation filter layer, F...filter part (frequency separation filter), S...
・Transparent part, MR...main information recording area, SR...
Sub information recording area, 50.51.52...Sub information generation circuit, 53.54.
55... Optical modulator, 56... Dichroic mirror group, 57... Optical deflector.

Claims (2)

[Claims] (1) A recording medium that includes at least a frequency resolution filter and an information recording layer and records main information and sub information, characterized in that the frequency resolution filter is provided only in the recording section of the main information. A recording medium for multiple information. (2) A recording method for recording main information and sub-information together on a recording medium including at least a frequency-resolving filter and an information recording layer, the plurality of sub-information being recorded at wavelengths corresponding to the frequency-resolving filter. A method for recording multiple pieces of information, characterized by multiplexing and recording using a plurality of electromagnetic radiation fluxes in the area.