JPH04139972A - Image pickup device - Google Patents

Abstract

PURPOSE:To prevent a voltage across a recording layer member from being fluctuated together with lapse of a voltage application time at recording by making a ratio of the sum of equivalent resistance sets to the sum of equivalent capacitance sets of a photosensitive layer member and a recording member nearly equal to a ratio of the equivalent resistance of the recording layer member to the equivalent capacitance of the photosensitive layer. CONSTITUTION:A ratio of an equivalent resistance Rm of a recording layer member CML to an equivalent capacitance Cc of a photosensitive layer member PCL is selected to be equal to a ratio of the equivalent resistance sum Rc+Rm to the equivalent capacitance sum Cc+Cm of the photosensitive layer member PCL and the recording layer member CML. Thus, it is prevented that the voltage V across the recording layer member CML is fluctuated uselessly together with lapse of voltage application time at recording. Thus, an optical modulation member or the like whose operating point has a threshold level is used as the recording layer member and image pickup with high quality having an excellent contrast is attained.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an imaging device that records electromagnetic radiation information using a photoreceptor layer member and a recording layer key, and the present invention relates to an imaging device that records electromagnetic radiation information using a photoreceptor layer member and a recording layer key. The present invention relates to an imaging device capable of capturing high-quality images with good contrast even when the open time and electrical shutter time are arbitrarily set variably.

(Prior Art) A device and method for recording electromagnetic radiation information using a photoreceptor layer member and a recording layer member is disclosed in Japanese Patent Application No. 1-2916130 as an invention and application filed by the present applicant. "Recording Medium and Recording and Reproduction Method" (filed on November 9, 1989), "Method for Recording Electromagnetic Radiation Information" described in Japanese Patent Application No. 229938 (February 12, 1990)
``Method for Recording Electromagnetic Radiation Information and Imaging Apparatus'' (filed on March 23, 1990) described in Japanese Patent Application No. 2-74390 (filed on March 23, 1990).

As shown in FIG.
The first and second electrodes E in the photoreceptor layer member PCL and the recording layer member CML disposed between the electrode Et2 of
11. E 12 is configured to supply a predetermined voltage between the two, and the electromagnetic radiation flux to be recorded (light incident from the subject 0 via the lens TL) is made incident on the photoreceptor layer member PCL. When recording electromagnetic radiation information targeted for recording on the recorded recording layer member CML, the amount of exposure of the electromagnetic radiation flux targeted for recording to the photoreceptor layer member PCL is set by an optical shutter PS. 1. Second electrode E
11. An electric switch consisting of a switch SW and a power source E is provided so as to apply a voltage showing a predetermined change mode between E and t2.

In the above-described hsI imaging device, the resistivity of the photoreceptor layer member PCL changes depending on the presence or absence of light (electromagnetic radiation) incidence, as will be detailed later, and carriers are generated at the site where light is incident. The apparent upper resistance value becomes smaller,
In other words, the dark resistivity becomes the bright resistivity), and as a result,
As the voltage across the recording layer member CML, the difference between the voltage change due to the dark resistivity and the voltage change due to the bright resistivity is recorded as a change in contrast voltage.

A subject image can be captured on such a photoreceptor layer member PCL (photoconductive layer)! Furthermore, in an imaging device that records information corresponding to the recording layer member CML (recording layer), it is necessary to set the shutter time to various values depending on the brightness of the subject and the purpose of use. For example, it can be used to capture an image of a subject in low illumination for a long time with a shutter to obtain the necessary contrast, or to capture a moving subject with an open shutter to record the trajectory of the subject's movement.

(Problem to be Solved by the Invention) However, in such an imaging device, as shown in FIG.
As shown in FIG. 2 and (B), the contrast potential (difference between bright area potential and dark area potential) on the recording layer portion $4' CML (recording layer) changes in accordance with the voltage application time. The voltage application time at which the contrast potential reaches its maximum value depends on the impedance (equivalent capacitance and resistance) of the photoconductive layer. When the bright resistivity of the photoconductive layer is large, long-term voltage application is required to maximize the contrast potential generated on the recording layer (
Same figure [A]).

Further, due to the relationship between the impedance of the recording layer portion +10ML (recording layer) and the impedance of the photoreceptor layer member PCL (photoconductive layer), a difference occurs in the time dependence of the voltage applied to the recording layer member CML (recording layer). In particular, when a light modulating material with a threshold value such as a polymer liquid crystal composite film is used in the recording layer (see Figure 4), the dark potential changes depending on the voltage application time, and the operating point changes depending on the voltage application time. There is a problem in that it varies depending on the shutter time (that is, the shutter time).

(Means for Solving the Problems) In order to solve the above problems, the present invention provides a photoreceptor layer member and a recording layer member disposed between the first electrode and the second electrode. While supplying a predetermined voltage between the electrodes, an electromagnetic radiation flux to be recorded is made to enter the photoreceptor layer member to record electromagnetic radiation information to be recorded on the recording layer member. In the imaging device, a ratio consisting of the sum of the equivalent resistance and the sum of the equivalent capacitance of the photoconductor layer member and the recording layer member, and a ratio consisting of the equivalent resistance of the recording layer member and the equivalent capacitance of the photoconductor layer member. An object of the present invention is to provide an imaging device in which the values are substantially equal.

(Function) In the above-described imaging device, the voltage across the recording layer member does not vary with the passage of voltage application time during recording.

(Embodiment) An embodiment of the imaging device according to the present invention will be described in detail below with reference to the drawings.

First, let us explain the configuration of the imaging device in Figures 2 (A) and (B).
) for details. In the same figures (A) and (B), O is the object, TL is the imaging lens, PS is the optical shutter, Ett is the transparent electrode, Et2 is the electrode, PCL is the photoconductor layer member made of a photoconductor, and CML is the recording material. In the layer members, SW is a switch, E is a power supply (voltage V), and CTL (
L) is an opening/closing control signal used to control the opening/closing operation of the optical shutter PS described above, and CTL (V) is an opening/closing control signal of the electric shutter, that is, supplies and cuts off an operating voltage to the imaging device. This is a switching control signal for switch SW. In the imaging device illustrated in the figure, a switch SW is provided between the transparent electrode Ell and the electrode Et2.
A power source E is connected through the electrode Et1 to generate a predetermined electric field between the transparent electrode Etl and the electrode Et2.

Moreover, the above-mentioned photoreceptor layer member PCL has a high-definition optical image on one end surface! A photoconductor having such characteristics that, when obtained, a high-definition charge image can be generated on the other end surface under the application of an electric field of appropriate strength. (For example, those using amorphous silicon, which is an inorganic material, and diazo pigment, which is an organic pigment) can be used.

The recording layer member CML described above is made of a material having a high insulation resistance value (for example, silicone resin) that allows the electrostatic latent image (charge image) formed on the surface of the recording layer member CML to remain in the same pattern for a long period of time. ), or liquid crystal, P
Various materials such as LZT, electrochromic shrine,
In other words, a recording layer member that records the information to be recorded by retaining a charge image by itself, or a recording layer member that records the information to be recorded by retaining a charge image, or a material that records the information to be recorded by a physical or chemical change that occurs in response to the applied electric field strength. Any recording layer member capable of recording information can be used. In addition, the recording layer member CML described above is, for example, a polymer-liquid crystal memory film formed by dispersing liquid crystal in a polymer material, that is, for example, methacrylic resin, polyester resin, polycarbonate resin, vinyl chloride resin,
Countless fine particles are randomly distributed in a porous polymeric material film such as polyamide resin, polyethylene resin, polypropylene resin, polystyrene resin, or silicone resin with a volume resistivity of 1014 Ωcm or more. A polymer mono-liquid crystal formed by sealing nematic liquid crystal or smectic liquid crystal, which exhibits a liquid crystal phase at room temperature and has a high volume resistivity, into pores, for example, pores with a diameter of about 0.5 microns or less. A memory membrane may also be used.

As shown in FIG. 2(C), in the imaging device, when the optical shutter PS is set to the open state by the opening/closing control signal CTL (L), the optical image of the object O is transferred to the transparent substrate BPI by the imaging lens TL. The image is formed on the photoreceptor layer member PCL via the transparent electrode Ell and the transparent electrode Ell. Furthermore, switch SW
Opening/closing control signal CTL (
V), when the switch SW is turned on, a predetermined voltage (from the discharge starting voltage between the photoreceptor layer member PCL and the recording layer member CML) is applied from the power source E between the transparent electrode Ell and the electrode Et2. A voltage of a high voltage value) is applied, and a record corresponding to the optical image of the subject O imaged on the photoreceptor layer member PCL is recorded on the recording layer member CM1. , is performed for .

When the light beam incident through the imaging lens TL during the period when the optical shutter PS is in the open state passes through the transparent electrode Ell and enters the photoreceptor layer member PCL, the electric resistance value of the photoreceptor layer member PCL changes to that value. The electric resistance value of each part of the photoreceptor layer member PCL changes in accordance with the light amount of each part of the subject, changing according to the light amount of the incident light flux (changing from dark resistivity to bright resistivity). In this state, the switch SW is turned on, and the voltage between the photoreceptor layer member PCL and the recording layer member CML is applied between the transparent electrode Etl and the electrode Et2. If a voltage that causes the voltage to be higher than the discharge starting voltage is applied, the state of change in the electrical resistance value in the photoreceptor layer portion t, I'PCL with respect to the recording layer member CML. A charge corresponding to 61 is deposited on the recording layer member CML, and an electrostatic latent image (charge image) corresponding to the optical image of the object and physical/chemical changes in response to changes in the electric field are recorded. That will happen.

Here, the electrical characteristics of the imaging device shown in FIGS. 2(A) and 2(B) will be described in detail. The equivalent resistance of the photoreceptor layer member PCL is R, the equivalent capacitance is C8, and the recording layer member CML is
Let R be the equivalent resistance and C be the equivalent capacitance. Then, the equivalent open circuit of the imaging device becomes as shown in Fig. 1, and the recording layer member CM
The step response for the voltage V across L is calculated as follows. However, that is, the voltage (2) across the recording layer member CML is the voltage V immediately after voltage application. is divided into capacitances (reciprocal ratio of 8m each), and as time passes, it shifts to resistance division.

Therefore, as shown in FIG. 3, the voltage V across the C end of the recording layer portion IJ increases with the passage of time (curve A); The voltage V between both ends will drop (curve B).

However, as described above, in the imaging device according to the present invention,
The sum of the equivalent resistances R+R and the equivalent capacitance Cm of the photoconductor layer member PCL and the recording layer member C; C. (R+R):
(C+C)=R:C c m c
Since it is composed of m m c, Co Rm C0CR+R CrtICIll.

Therefore, as shown in FIG. 3, the voltage across the recording layer member CML does not change unnecessarily with the elapse of the voltage application time during recording v1 (curve C). Therefore, even if a light modulating material having a threshold value such as a polymer-liquid crystal composite film whose characteristics are shown in FIG. 4 is used as the recording layer member CML, the dark potential will not change depending on the electric field application time. In other words, the operating point of the light modulating material functioning as the recording layer member CML does not change.

In this way, according to the present imaging device, even if the electrical shutter time (electric field application time) is changed depending on the imaging state,
Imaging results do not vary and high-quality imaging can be performed.

(Effects of the Invention) As described in detail above, according to the present invention, even if the optical shutter opening time and the electrical shutter time are arbitrarily set variably according to the imaging state, the recording layer section 4 Since the dark potential does not change depending on the electric field application time, it is possible to use a light modulator having a threshold value at the operating point as a recording layer member, and it is possible to perform high-quality imaging with good contrast. can.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an embodiment of an imaging device according to the present invention.
2(A) and 2(B) are block diagrams of the imaging device, FIG. 2(C) is a diagram illustrating the Nyatta time, and FIG. 3 is a diagram of the recording layer member (recording layer). A diagram illustrating the difference in the time dependence of such voltage, FIG. 4 is a diagram illustrating the relationship between the applied voltage of the recording layer portion +4 and the characteristics (transmission] 3 rate), and FIG. 5 is a diagram illustrating the conventional example.
FIGS. 6A and 6B are diagrams showing the relationship between the electric field application time and the voltage across the recording layer member. 0...Subject, TL...Imaging lens, PS...Optical shutter, Ell...Transparent electrode, Et2...Electrode, PCL...
・Photoconductor layer member by photoconductor, CML...recording layer member, SW...switch, E...power supply, R...equivalent resistance of photoconductor layer member, C...of photoconductor layer member Equivalent capacitance, R...Equivalent resistance of the recording layer member, C...Equivalent capacitance of the recording layer member.

Claims (1)

[Claims] A predetermined voltage is supplied between the electrodes of a photoreceptor layer member and a recording layer member disposed between a first electrode and a second electrode, and a recording target is applied to the photoreceptor layer member. In an imaging device that records electromagnetic radiation information targeted for recording on the recording layer member by making the electromagnetic radiation flux incident thereon, the sum of the equivalent resistances and the equivalent capacitance of the photoreceptor layer member and the recording layer member. 1. An imaging device characterized in that the ratio of the sum of the sum of the two and the ratio of the equivalent resistance of the recording layer member and the equivalent capacitance of the photoreceptor layer member are approximately equal to each other.