JPH0979901A - Information converting element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect a picture pattern as it is so that a picture can be recognized in parallel with the detection of the picture pattern by detecting the concentration pattern change of a film permeating material which occurs when an image is optically or thermally inputted to a functional film. SOLUTION: A cell 1 is divided into two areas by a partition wall 2 and the opening of the wall 2 is closed with a functional film 3. One area is filled up with a high- concentration solution 4 containing a film permeating material (A) at a high concentration and the other area is filled up with a low-concentration solution 5 containing the material (A) at a low concentration. Then a small electrode 6 is fitted to the internal surface of the cell 1 on the solution 5 side so that the front end of the electrode 6 can be positioned within the extent of the diffusion layer of the film 3. When a picture pattern is inputted to the film 3 through a light transmitting window 1a , the film permeating characteristic of the material A changes. The change is transmitted to the solution 5 and the material (A) generates a concentration pattern which varies depending upon the distance from the film 3 and the time after the picture pattern is inputted. The electrode 6 and a counter electrode 7 detect the concentration pattern and send the pattern to a detecting and processing device 8 for processing. Therefore, the input picture pattern can be detected as the concentration pattern of the material A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information conversion element, and more particularly to an information conversion element capable of processing images in parallel.

[0002]

2. Description of the Related Art In electric and electronic devices, recognition of images, characters, symbols, etc. plays a central role in so-called man-machine interface between human and machine. As is well known, recognition by electronic means has made rapid technological progress in recent years, has brought about innovations in the fields of information processing equipment, communication equipment, measuring equipment, etc., and has also expanded into areas closely related to our daily lives. It was way. To date, most of these recognition techniques mainly use a combination of semiconductor devices such as silicon. However, the conventional information processing method based on semiconductor device-based electronic technology is generally suitable for serial processing such as logical operation because it generally uses a sequential arithmetic method, but it is very suitable for large-scale processing such as image and pattern processing. It is generally not suitable for simultaneous and parallel processing of information.

For example, a CCD (charge coupled device) image sensor is known as a conventional method for processing an external light image pattern. In this CCD image sensor, the miniaturized light receiving element and the conversion element are two-dimensionally integrated, the input image is divided into mosaics, and the information received by each element is independently and sequentially electrically measured to form an image. Is reproduced. For this reason, there is a disadvantage in recognizing an image that a large amount of information must be processed and converted.

On the other hand, with the elucidation of life or biological phenomena, expectations for the development of materials and devices based on new ideas based on the excellent functions of living bodies are increasing. In other words, by mimicking biological phenomena, information processing, recognition,
It is based on the idea of developing materials and devices that are based on principles that are different from conventional semiconductor technology in terms of memory, etc., and bear new electronic technology that fits more people.

Among the many phenomena peculiar to biological systems, the most basic form of information conversion / processing is based on dynamic and parallel processing by reaction or diffusion of substances in or between cells. . For example, the visual system processes 70 to 80% of information coming from the outside, and is considered to play the most important role in information processing in the biological system. In the information conversion in this visual system, first, light signals were converted into substances using a chemical reaction in the photoreceptor cell layer that was two-dimensionally arranged in the retina, and then functionalized through various subsequent reactions. It has been elucidated that signals are processed and integrated in parallel while passing through several nerve cell layers, and finally sent to the brain as electric nerve pulses.

Conventionally, the following methods have been known as methods that imitate such information processing in a living body. For example, a solution is placed with a film containing a photochemical reaction substance sandwiched therebetween, and a pair of electrodes immersed in the solution on both sides of the film are provided, and these electrodes are incorporated into a part of an electric oscillation circuit to An optical sensor that utilizes the fact that the oscillation pattern changes due to changes in the electrical properties of the film, such as the capacitance and electrical conductivity of the film, is proposed (H. Nakanis).
hi and H. Yamaguchi: Bioele
ctrochem. Bioenerg. , 32 volumes, 27
Page (1993)). However, this optical sensor does not assume parallel conversion and processing of image information from the outside.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and by converting image information from the outside into a dynamic concentration change of a substance,
It is an object of the present invention to provide a novel information conversion element that enables parallel processing.

[0008]

The information conversion element of the present invention comprises a functional film containing a substance that undergoes a physical or chemical change by light or heat, and a medium arranged in contact with both sides of the functional film. And the membrane-permeable substance contained in the medium so that the concentration is low and high in the medium on both sides of the functional membrane, and the functionality in the medium in which the membrane-permeable substance is set to a low concentration. An electrode which is arranged within the range of the diffusion layer of the membrane-permeable substance from the membrane, and which detects the concentration pattern change of the membrane-permeable substance due to image input by light or heat to the functional film. To do.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. In the present invention, the substance (or aggregate of substances) contained in the functional film is not particularly limited as long as it causes a physical or chemical change in atomic / molecular structure or electronic structure by light or heat. Not done. For example, as an organic substance, a substance that causes a heterocyclic cleavage reaction such as spiropyrans, a substance that causes cis-trans isomerization such as azobenzenes and stilbenes, and strain deformation such as between norvonadiene and quadxylene. And a substance that causes an electron transfer reaction between two kinds of molecules that act as an electron donor and an electron acceptor. Examples of protein molecules include bacteriorhodopsin and its analogues extracted from highly halophilic bacteria, and visual pigment rhodopsin contained in photoreceptor cells in retinas of various animals. In addition to these changes accompanied by chemical changes, changes in the aggregate structure of the membrane may be caused by light or heat, such as a crystal-amorphous transition and a phase transition such as a polymorphism of lipids. However, among these materials, it is preferable to use a substance that generally has a high yield of reaction or change from the viewpoint of response sensitivity. Further, it is also possible to perform a treatment responding to an input of multiple wavelengths by incorporating a plurality of kinds of substances having different light or heat absorption regions in the functional film. For example, a color image can be detected by using three kinds of substances that respond to red, green, and blue absorption regions.

The form of the functional membrane used in the present invention is not particularly limited as long as it does not inhibit the membrane permeation of the membrane permeable substance, and may be a solid membrane or a liquid membrane. Specifically, various materials such as a lipid bilayer membrane, a lipid-impregnated membrane, and an inorganic / organic polymer membrane can be used. The planar shape of the functional film is not particularly limited, and may be circular or polygonal, for example. Further, as a substrate for fixing and holding the functional film, a metal substrate having a single hole or a porous, a semiconductor substrate,
Insulator substrate or those whose surface is treated by coating etc., or organic or inorganic porous filter such as cellulose type, fluororesin type, vinyl chloride type, acrylonitrile type, polycarbonate type, carbon fiber type etc. Can be used.

In the present invention, the membrane-permeable substance used for transmitting information may be any substance as long as its permeability changes with the structural change of the membrane due to light or heat.
As the membrane-permeable substance, for example, hydrogen ion, oxygen ion, metal ion, metal complex ion, metal oxide ion,
Various inorganic ions such as halogen ions can be used. In addition, various neutral atoms, organic molecules or organic molecular ions can be used.

In the present invention, the medium holding the membrane permeable substance is not particularly limited, and various media can be used depending on the type of the membrane permeable substance. For example, an organic solvent can be used as the liquid medium in addition to water. Examples of the organic solvent include hydrocarbons such as hexane and toluene, ethers such as dioxane, alcohols, acetonitrile and the like. As the gel medium, gelatin, polyacrylamide or the like can be used. As the solid medium, ion conductive polymers such as polyethylene oxide and polypropylene oxide, oxide ion conductors such as zirconia and β-alumina, halide ion conductors such as calcium fluoride and silver iodide, silicon and germanium, etc. Various semiconductors and the like can be used. However, it is preferable to use a liquid medium or a gel medium in consideration of the controllability and response speed of the device.

In the present invention, the medium is placed in contact with both sides of the functional membrane, and the membrane permeation through the medium is made to be low and high in the medium on both sides of the functional membrane. The concentration difference of the volatile substance is set. Therefore, the membrane-permeable substance permeates the functional membrane from the high-concentration side to the low-concentration side by using the difference in concentration as a driving force. Furthermore, in order to increase the moving speed of the membrane permeable substance and improve the detection speed, at least one kind of electric field, magnetic field or pressure may be externally applied to the membrane permeable substance through the medium. .

The medium and the functional film separating the medium into two regions are housed in a predetermined cell. For this reason,
In order to make an image pattern of light or heat incident on the functional film, it is preferable that the medium-side cell wall surface in which the concentration of the film-permeable substance is set to a high concentration is formed of a light- or heat-permeable material.

In the present invention, the electrode for detecting the change in the concentration pattern of the membrane-permeable substance is not particularly limited, but an electrode capable of substance-selective detection is preferable in order to detect only the target substance with high sensitivity, For example, an ion selective electrode is used. The ion-selective electrode has an ion-selective membrane that responds to specific ions on the surface, and detects membrane potential fluctuations due to the concentration difference of the ions to be measured.
More specifically, an ion-selective membrane is immobilized directly or through an internal standard solution on the surface of a miniaturized saturated calomel electrode or a reference electrode such as a silver / silver chloride electrode; Microfabricated field effect transistor (FET) micro ion selective FET provided with ion selective film on gate insulating film
Electrodes and the like. For ion-selective electrodes, hydrogen ions, alkali metal ions such as sodium and potassium ions, alkaline earth metal ions such as calcium and barium, and halogen ions such as chlorine and iodine ions can be used by using an appropriate ion-selective membrane. ion,
Alternatively, various ions such as ammonium ions can be detected. The measurement of potential by the ion-selective electrode is performed on a reference electrode provided separately.

Further, for example, an electrode for detecting an electric current associated with redox of a membrane-permeable substance such as a target atom or molecule or ions thereof can be used. As a substance forming such an electrode, platinum, gold, carbon or the like is usually used from the viewpoint of chemical stability and reaction activity on the surface. A non-metal or organic conductor may be used depending on the type of the membrane-permeable substance.
Further, a counter electrode and a reference electrode as needed are provided for this electrode. As described above, in the method of detecting the current associated with the redox of the membrane-permeable substance, the substances having different redox potentials in the medium can be detected with high sensitivity by manipulating the potential of the electrode, and moreover, as the electrode. It is possible to use a material having a simple structure and extremely easy microfabrication processing.

In the present invention, the electrode for detecting the change in the concentration pattern of the membrane permeable substance is the diffusion layer of the membrane permeable substance from the functional membrane in the medium in which the concentration of the membrane permeable substance is set to a low concentration. It is located within the range. The diffusion layer is a layer in which a concentration gradient occurs in the medium due to mass transfer due to diffusion, and usually refers to a region of about 500 μm from the surface of the functional film. The size of the electrode is preferably at least smaller than the diameter of the functional membrane or the length of the longest diagonal in order to detect the change in the two-dimensional concentration pattern of the membrane-permeable substance. The number of electrodes may be single or plural. The counter electrode and / or the reference electrode, which are provided as necessary, are provided in the medium in which the concentration of the membrane permeable substance is set to a low concentration, like the detection electrode. It is desirable to place it in a position that does not interfere with the diffusion of the substance. Further, the electric signal detected by the electrode is signal-processed by a separately provided detection processing device.

Next, the operating principle of the information conversion element of the present invention will be described. First, when an image pattern due to light or heat is input to the functional film, a physical or chemical structural change occurs in the substance existing in that part. As a result, the membrane permeability of the membrane permeable substance contained in the medium and diffusing inside the functional membrane from the high concentration side to the low concentration side changes. Due to such a change in the membrane permeability of the membrane permeable substance, the diffusion state of the membrane permeable substance changes three-dimensionally in the portion where the image pattern of the functional membrane is input. This change is transmitted to the medium where the concentration of the membrane-permeable substance is low, and in the vicinity of the functional membrane, the concentration pattern of the membrane-permeable substance is generated depending on the distance from the membrane and the time after the image pattern is input. To do. Macroscopically, the change in the concentration pattern becomes uniform and approaches a constant value as the diffusion distance of the membrane-permeable substance from the functional film increases with the passage of time. However, within the time until this constant value is reached, in the area near the functional film, that is, in the diffusion layer, the concentration of the membrane-permeable substance that spatially and temporally reflects the information of the image pattern input to the functional film. A pattern is formed. Then, since the electrode capable of detecting the concentration of the membrane permeable substance is arranged in the diffusion layer, the image pattern input to the functional film can be detected as the concentration pattern of the membrane permeable substance. Based on the above principle, it is possible to realize an element capable of converting image information into another information and detecting it. In this case, a higher-level image pattern can be detected by previously providing an image pattern learning storage circuit in the apparatus and associating the image pattern with the detection signal.

When only one electrode is used, it becomes difficult to recognize, for example, the concentration pattern of the membrane-permeable substance that is point-symmetric with respect to the electrode, that is, the image pattern to be input. Therefore, in order to detect an arbitrary two-dimensional input image pattern, it is desirable to provide three or more electrodes in a non-linear arrangement.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view showing an example of the information conversion element of the present invention. In FIG. 1, a partition 2 having an opening is attached to the center of a cell 1, and a functional film 3 is provided in the opening of this partition 2. The partition 2 and the functional film 3 divide the inside of the cell 1 into two regions. One of the partitioned areas in the cell 1 has a high-concentration solution 4 containing a membrane-permeable substance at a high concentration, and the other has a low-concentration solution 5 containing a membrane-permeable substance at a low concentration. It is housed. A light transmission window 1a is provided on the wall surface of the cell 1 holding the high concentration side solution 4 so that image pattern information from the outside can be incident on the functional film 3. A microelectrode 6 for detecting the concentration of the membrane-permeable substance is attached to the wall surface of the cell 1 holding the low-concentration solution 5, and the tip of the microelectrode 6 is in the vicinity of the functional film 3, that is, in the range of the diffusion layer. It is located inside. Also, the functional film 3 in the low-concentration solution 5
The counter electrode 7 of the microelectrode 6 is provided at a position away from. The signal obtained from the microelectrode 6 and the counter electrode 7 is detected by the detection processing device 8 and signal processing is performed.

As an example of the microelectrode 6, FIG. 2 shows an enlarged tip of the microoxidation / reduction electrode for detecting a change in current due to redox of the membrane-permeable substance. As shown in FIG.
The periphery of the electrode 61 is shielded by an insulator 62, and only the end face for detection is exposed. When the membrane-permeable substance is an ion and this is detected using an ion-selective electrode, the ion-selective membrane provided at the electrode tip of FIG. 2 is used.

When an ion selective electrode is used, a so-called reference electrode is used as the counter electrode 7 in FIG. Further, when detecting a current change due to a redox reaction of a membrane-permeable substance, both the counter electrode and the reference electrode may be arranged.

FIG. 3 shows a sectional view of an information conversion element having the same structure as that of FIG. 1 except that a plurality of microelectrodes 6 are used. Example 1 An information conversion element having the configuration shown in FIG. 1 was produced as follows.

First, a nickel substrate having a hole diameter of 600 μm and a surface coated with a fluororesin having a thickness of 10 μm was prepared. A bilayer membrane of monoolein containing 4′-octylazobenzene-4-oxybutyric acid, which is a lipid molecule having an azobenzene group, was formed in the opening of this nickel substrate to form a functional membrane.

The nickel substrate having the functional film 3 thus formed was used as the partition wall 2 of the information conversion element shown in FIG. Water was used as the medium, potassium chloride was used as the membrane permeable substance, and the concentration of the high concentration side solution 4 was set to 10 mmol and the concentration of the low concentration side solution 5 was set to 0.01 mmol. As the microelectrode 6, a potassium ion-selective microelectrode (electrode diameter: 50 μm) in which a valinomycin-containing polymer film is immobilized on a silver electrode is used, and the tip of the microelectrode is provided with the functional films 3 to 15
It was fixed so as to be arranged at a position of 0 μm.

Using this information conversion element, as shown in FIG. 4, although the integrated intensity of the entire area to be irradiated is constant, light having a wavelength of 355 nm forming three types of image patterns having different shapes is supplied to the functional film 3. Irradiation was performed for 1 second each, and a change in potassium ion concentration with time was detected. As a result, FIGS. 4 (a) to 4 (c)
As shown in Fig. 3, the concentration pattern of potassium ions showing a time-dependent change depending on the shape of the incident image was obtained.

For comparison, the microelectrode 6 was moved to a position 10 mm from the functional film 3 and the same measurement was performed, but no difference in response due to the incident image pattern was observed.

Example 2 A silver / silver chloride electrode was dipped in each of the high-concentration solution 4 and the low-concentration solution 5, and 20 along the film thickness direction of the functional film 3.
The time course of the potassium ion concentration was detected in the same manner as in Example 1 except that an electric field of 0 mV was applied.

As a result, the detection rate of the potassium ion concentration was 5 times higher than that in the case of Example 1 for all the image patterns. Example 3 An information conversion element similar to that of Example 1 was prepared, except that a lipid bilayer membrane composed of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine was used as the functional membrane.

Using this information conversion element, the functional film 3 was irradiated with infrared rays having a wavelength of 2.5 μm or more, which form three types of image patterns as shown in FIG. 4, and the change with time of the potassium ion concentration was detected. As a result, the potassium ion concentration pattern showing the time-dependent change depending on the shape of the incident image was obtained.

Example 4 1 ', 3'-dihydro-3', 3'-dimethyl-6- which is a lipid molecule having a spiropyran group as the functional membrane 3
Nitro-1'-octadecyl-8-docosanoyloxymethylspiro [2H-1-benzopyran-2,2'-
Triolein containing [2H] indole was added to a porous filter made of acetyl cellulose (pore size: 0.3μ).
What was impregnated in m) was used. Using water as a medium and p-benzoquinone as a membrane-permeable substance, the concentration of the high concentration side solution 4 was 10 mmol, and the concentration of the low concentration side solution 5 was 0.01.
It was set to mmol. As the microelectrode 6, a platinum electrode (electrode diameter: 1
0 μm), the tip of which is 100 μm from the functional film 3
It was fixed so that it would be placed in the position. In this way,
An information conversion element similar to that in Example 1 was produced.

Using this information conversion element, the functional film 3 was irradiated with light having a wavelength of 355 nm, which forms three types of image patterns as shown in FIG. 4, for 1 second, respectively, and the change with time in the p-benzoquinone concentration was detected. . As a result, FIG.
Similar to (c), a p-benzoquinone concentration pattern showing a change with time depending on the shape of the incident image was obtained.

Example 5 As a functional film, 3,4- (1,4,7,10,13-pentaoxatridecane-1,13-diyl) benzyl-
A polyvinyl chloride polymer film (thickness: 0.10 mm) containing p- (phenylazo) benzoate was used. Polyethylene oxide, which is a solid electrolyte, was used as the medium, and lithium perchlorate was used as the membrane-permeable substance. As the microelectrode 6, an ion selective electrode (electrode diameter: 50 μm) in which a polymer film containing dodecylmethyl-14-crown-4 was fixed on a silver electrode was used. In this way, an information conversion element similar to that of Example 1 was manufactured.

Using this information conversion element, the functional film 3 was irradiated with light having a wavelength of 355 nm, which forms three types of image patterns as shown in FIG. 4, for 1 second, respectively, and changes in the lithium ion concentration with time were detected. As a result, FIGS. 4 (a) to 4 (c)
Similarly, a lithium ion concentration pattern showing a time-dependent change depending on the shape of the incident image was obtained.

[0035]

As described in detail above, according to the information conversion element of the present invention, the image pattern can be detected as it is with only a very small number of electrodes, that is, one to a few electrodes. It becomes possible to recognize.

[Brief description of drawings]

FIG. 1 is a sectional view showing an example of an information conversion element according to the present invention.

FIG. 2 is an enlarged cross-sectional view showing a tip portion of an electrode used in the information conversion element according to the present invention.

FIG. 3 is a sectional view showing another example of the information conversion element according to the present invention.

FIG. 4 is a characteristic diagram showing changes over time in a concentration pattern of a membrane-permeable substance corresponding to an image pattern, which is detected by using the information conversion element according to the present invention.

[Explanation of symbols]

1 ... Cell, 2 ... Partition wall, 3 ... Functional film, 4 ... High concentration side solution, 5 ... Low concentration side solution, 6 ... Micro electrode, 7 ... Counter electrode, 8 ...
Detection processing device, 61 ... Electrode, 62 ... Insulator.

Claims (3)

[Claims] 1. A functional film containing a substance which undergoes a physical or chemical change by light or heat, a medium arranged in contact with both sides of the functional film, and a medium on both sides sandwiching the functional film. Range of the membrane permeable substance contained in the medium so as to have a low concentration and a high concentration, respectively, and the diffusion layer of the membrane permeable substance from the functional film in the medium in which the membrane permeable substance is set to a low concentration. An information conversion element, which is disposed inside the electrode, and which includes an electrode for detecting a change in concentration pattern of the film-permeable substance due to image input by light or heat to the functional film. 2. The information conversion element according to claim 1, wherein the medium is a liquid, and the membrane-permeable substance is an atom, a molecule, or an ion thereof. 3. The information conversion element according to claim 1, wherein the electrode is a fine redox electrode or a fine ion selective electrode having a detection area having a size equal to or smaller than the film diameter of the functional film. .