JP2003005389A - Method and apparatus for evaluating characteristic of photoreceptor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To evaluate various photoreptor characteristics related to electrophotography simultaneously with detection of defects on the surface of a photoreceptor. SOLUTION: An electrifying means 103, a pre-exposure means 104, and a defect detection means 108 are arranged in the outer peripheral part of the photoreptor 101 and a rotation means 102, and a unit 107 to which an image exposure means 105 and a surface potential measuring means 106 are attached is arranged in the outer peripheral part of them. The unit 107 and the defect detection means 108 can be freely moved in the generatrix direction of the photoreceptor 101 by moving means 109 and 110 respectively. In this constitution, the unit 107 and the defect detection means 108 are moved to different positions in the generatrix direction of the photoreceptor 101 to be able to simultaneously operate the surface potential measuring means 106 and the defect detection means 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoconductor characteristic evaluation apparatus and a photoconductor characteristic evaluation method for evaluating the characteristics of an electrophotographic photoconductor, and more specifically, to an amorphous silicon photoconductor (hereinafter a-Si). (Hereinafter abbreviated as “photoreceptor”) and a photoreceptor characteristic evaluation method and apparatus.

[0002]

2. Description of the Related Art A photoconductor is one of the most important components in an electrophotographic apparatus such as a copying machine and a laser printer to which an electrophotographic process is applied. It is necessary to satisfy various characteristics.

Therefore, before the shipment of the photoconductor, the photoconductor is inspected for various characteristics relating to electrophotography. When developing a new photoconductor for a new electrophotographic apparatus, various characteristics relating to electrophotography of a photoconductor prototyped in the development process are evaluated.

Conventionally, as an evaluation method for evaluating various characteristics of a photoconductor, an existing copying machine or a device modified from the existing copying machine for evaluating the photoconductor is used, and the photoconductor is mounted on these devices. Then, a method of measuring various characteristics of the photoconductor is often used.

Dedicated evaluation devices for evaluating various characteristics of the photoconductor include, for example, Japanese Patent Publication No. 64-11946, Japanese Patent Application Laid-Open No. 4-26582, and Japanese Patent Application Laid-Open No. 4-40.
As described in Japanese Patent Publication No. 463 or the like, there is known a structure in which measuring devices such as a charger, a light source, and a potential measuring sensor are arranged around a rotating photoconductor.

Further, in Japanese Unexamined Patent Publication No. 6-27082, a unit equipped with a measuring device such as a charger, a light source, and a potential sensor is moved in the busbar direction of the photoconductor to eliminate characteristic unevenness in the busbar direction of the photoconductor. Techniques for measuring are disclosed.

Further, in order to form a good image as an electrophotographic photosensitive member from the beginning of use, it is necessary to evaluate the presence or absence of defects existing in the photosensitive member, in addition to the above-mentioned characteristic evaluation. Of the defects on the surface of the photoconductor, those that can be visually detected are easy to detect, but it is not easy to detect the presence of minute pinholes, ball field protrusions, and the like.

Conventionally, as an evaluation method for evaluating the presence or absence of defects such as minute pinholes existing on the photoconductor, the photoconductor is mounted on an existing copying machine to perform image formation, and the image is printed on the surface of the photoconductor. Generally, a method for evaluating the defects of is known.

Further, as a dedicated evaluation device for evaluating the presence or absence of a defect existing on the photoconductor, for example, special registration 26740
Japanese Patent Laid-Open No. 02-202 discloses an apparatus for evaluating defects on the surface of a photoconductor using a detection electrode. This device holds a detection electrode with an area of about 1 mm ^{2 at} a distance of about 1 mm from the surface of the photoconductor, and detects the potential of the detection electrode by a voltage dividing capacitor or amplifier connected to the detection electrode. The device measures the potential decrease rate of the detection electrode when the defective portion on the surface of the photoconductor approaches the detection electrode, and determines the presence or absence of the defect on the surface of the photoconductor and the size thereof. With this device, evaluation is performed for relatively large defects of 0.4 mm to 1 mm or more.

Further, Japanese Patent Publication No. 3030398 discloses a method of measuring the uniformity of surface potential using a detection electrode. In this method, the sensing electrode is arranged in the vicinity of the surface of the photoconductor on which the measurement is performed, and the sensing electrode is moved relative to the surface of the photoconductor to induce an induced current in the sensing electrode due to a change in the potential of the surface of the measurement. Is generated and analyzed to measure the uniformity of the surface potential. The detection electrode has an edge, and the feature is that the potential change of the measurement portion on the surface of the photoconductor is detected by the edge of the detection electrode.

Further, Japanese Patent Application Laid-Open No. 11-184188 discloses a method of measuring a minute potential change on the surface of a photoconductor using a detection electrode. This method is also a method of reading a minute potential change on the surface of the photoconductor by an induced current generated by moving the detection electrode relative to the measurement portion on the surface of the photoconductor. In this method, the width of the detection electrode is made smaller than the width of the potential change of the electrostatic latent image to be measured, and by using the detection electrode having no edge, higher resolution measurement is possible. .

[0012]

However, in the evaluation device as described above, it is not possible to perform both the potential characteristic evaluation of the photoconductor and the defect detection, so that the potential characteristic evaluation and the defect detection of the photoconductor are performed. Needs to prepare a dedicated device for each evaluation. Therefore, there is a problem that more cost is required to prepare a comprehensive evaluation system including potential characteristic evaluation to defect detection. In addition to that, work such as attaching and detaching the photoconductor to each device and operating each device, etc.
There is a problem that a lot of work is required and a lot of time is spent on the evaluation itself.

Further, when detecting the presence or absence of a defect on the surface of the photoconductor by the change in the surface potential of the photoconductor, the surface of the photoconductor to be measured must be macroscopically uniformly charged. On the other hand, when evaluating the potential characteristics of the photoconductor, since the charging characteristics and the exposure characteristics are measured while changing the charging conditions and the exposure conditions, the potential of the surface of the photoconductor to be measured fluctuates moment by moment. .

As described above, since the measurement conditions of the detection of the defect of the photoconductor and the evaluation of the potential characteristic are opposite to each other, the defect detection and the evaluation of the potential characteristic of the photoconductor can be performed by simply combining the respective evaluation methods or the evaluation devices. Was difficult to do.

Further, the a-Si photosensitive member has a large electrostatic capacity and low charging property as compared with an organic photosensitive member such as OPC which is widely used as an electrophotographic photosensitive member.
Therefore, the requirement for charging property is strict, and the leveling effect by the grid electrode of the charger is smaller than that of the organic photoconductor. As a result, the charging characteristics and the charging unevenness characteristics are often one of the important issues when inspecting or developing and designing an a-Si photosensitive member. Therefore, when evaluating the charging characteristics of the a-Si photosensitive member, it is necessary to establish a measuring method capable of detecting the charging characteristic difference of the photosensitive member with high accuracy.

Further, although the characteristics of the photoconductor relating to the optical memory are important photoconductor characteristics that directly affect the image quality, the evaluation of the characteristics has hitherto been made by using an image forming means such as a copying machine. However, only visual evaluation of the generated image was performed, and there was room for improvement in its quantitativeness.

The present invention has been made in view of the problems of the above-described conventional techniques, and includes defect detection for detecting minute defects on the surface of the photoconductor, charging characteristics, photosensitive characteristics, and dark decay characteristics. In addition to being able to simultaneously evaluate various characteristics related to the electrostatic latent image of electrophotography, such as optical memory characteristics, a comprehensive evaluation of the photoconductor can be performed with simple work.
An object of the present invention is to provide a photoreceptor characteristic evaluation device and a photoreceptor characteristic evaluation method that can be performed in a short time.

[0018]

In order to achieve the above object, the photoconductor characteristic evaluation apparatus of the present invention has the following constitution.

That is, the photoconductor characteristic evaluation apparatus of the present invention comprises a rotating means for rotating a cylindrical photoconductor, a charging means for charging the photoconductor, an exposing means for exposing the photoconductor, and the photoconductor. At least a surface potential measuring means for measuring the surface potential of the, and a defect detecting means for detecting a defect on the surface of the photoconductor by using a probe that generates an induced current according to a potential change on the surface of the photoconductor, The surface potential measuring means and the defect detecting means can operate simultaneously.

Further, the surface potential measuring means and the defect detecting means operate simultaneously at different positions in the direction of the generatrix of the photoconductor.

Further, one or more units arranged on the outer peripheral portion of the photoconductor, to which at least the exposing unit and the surface potential measuring unit are attached, and the first unit for moving the units in the generatrix direction of the photoconductor. Second moving means for moving the defect detecting means and the defect detecting means in the generatrix direction of the photoconductor.
And a second moving means, the first moving means and the second moving means.
The moving means is capable of being independently driven.

Further, a plurality of units arranged at the outer peripheral portion of the photoconductor, to which at least the exposing unit and the surface potential measuring unit are attached, and a moving unit for moving the defect detecting unit in the generatrix direction of the photoconductor. And the plurality of units are arranged so as to be relatively fixed with respect to the generatrix direction of the photoconductor.

Further, one or more units arranged at the outer peripheral portion of the photoconductor, to which at least the exposing means and the surface potential measuring means are attached, and a moving means for moving the units in the generatrix direction of the photoconductor. And the defect detecting means is arranged over the entire area of the photoconductor in the generatrix direction.

Further, at least the charging means, the exposing means, and the surface potential measuring means, which are arranged on the outer peripheral portion of the photoconductor and have an effective charging range in the generatrix direction of the photoconductor of 2 cm or more and 15 cm or less, are attached. And at least one unit, a first moving unit that moves the unit in the generatrix direction of the photoconductor, and a second moving unit that moves the defect detection unit in the generatrix direction of the photoconductor, The first moving means and the second moving means can be independently driven.

Further, at least the charging means, the exposing means, and the surface potential measuring means, which are arranged on the outer peripheral portion of the photoconductor and have an effective charging range in the generatrix direction of the photoconductor of 2 cm or more and 15 cm or less, are attached. One or more units and a moving unit that moves the defect detection unit in the generatrix direction of the photoconductor, and the plurality of units are arranged relatively fixed with respect to the generatrix direction of the photoconductor. It is characterized by being.

Further, the unit is characterized in that a plurality of the surface potential means are attached.

Further, the unit is provided with eccentricity amount measuring means for measuring an eccentricity amount when the photosensitive member rotates and generating a warning signal when the measured eccentricity amount exceeds a predetermined value. It is characterized by being.

Further, the unit is equipped with surface temperature measuring means for measuring the surface temperature of the photoconductor.

Further, in the detection portion of the defect detecting means, the width of the photosensitive member in the rotation direction is smaller than the width of the portion of the surface of the photosensitive member to be measured in which the potential changes, and the surface of the photosensitive member is smaller. It is characterized in that a cross section of a plane perpendicular to the direction parallel to the rotation direction of the photoconductor has no edge.

The sectional shape of the detection portion of the defect detection means is a perfect circle.

Further, the cross-sectional shape of the detection portion of the defect detecting means is elliptical.

Further, the cross-sectional shape of the detection portion of the defect detecting means is characterized in that at least three arcs are connected by a radius, and any one of the arcs faces the surface of the photoconductor.

The detecting portion of the defect detecting means is made of a conductive wire having a wire diameter of φ1 or more and φ500 μm or less, and the length of the photosensitive member in the generatrix direction is 0.2.
When the rotation direction of the photoconductor is the X axis, the normal direction of the photoconductor surface is the Y axis, and the direction perpendicular to the X axis and the Y axis is the Z axis, It is characterized by being arranged in parallel.

The material of the detection portion of the defect detection means is tungsten.

The charging means is a corotron charger.

Further, it has a memory means for storing the output from the surface potential measuring means, the rotating means generates a rotation signal when the photosensitive member is rotated, and the memory means receives the rotation signal according to the rotation signal. It is characterized in that it operates in synchronization with the rotation of the photoconductor.

Further, the rotating means generates a pulse signal as the rotation signal every time the photosensitive member makes one rotation.

Further, it has a rotation detecting means for generating a rotation signal when the rotation of the photoconductor is detected, and a memory means for storing an output from the surface potential measuring means. Is operated in synchronization with the rotation of the photoconductor.

Further, the rotation detecting means generates a pulse signal as the rotation signal every time the photosensitive member makes one rotation.

Further, the photoconductor is characterized by having a photoconductive layer containing amorphous silicon as a main component.

(Operation) In the present invention constructed as described above, the defect detecting means and the unit to which the potential measuring means is attached are arranged at different positions in the bus line direction of the photoconductor, and the defect detecting means and the potential are detected. By simultaneously operating the measuring means, it is possible to achieve both defect detection and potential measurement in which the measurement conditions conflict with each other.

Furthermore, since the defect detecting means according to the present invention is very small and highly accurate, it can be moved inside the highly accurate potential measuring unit including the crossing, so that the inspection time is greatly increased. Reduction is achieved.

In addition, as an application form of these, by attaching a charging means or the like to the unit, the unit is integrated to simplify the apparatus structure, or a plurality of units are continuously arranged in the generatrix direction of the photoconductor. It is possible to further reduce the inspection time by increasing the number of units.

[0044]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings and experimental examples.

1A and 1B are schematic views showing an embodiment of a photoreceptor characteristic evaluation apparatus of the present invention, where FIG. 1A is a front view and FIG. 1B is a right or left view of FIG. FIG.

In the photoreceptor characteristic evaluation apparatus shown in FIG. 1, a charging means 103 and a pre-exposure means 104 are arranged on the outer peripheral portion of a cylindrical photoreceptor 101 and a rotating means 102 for rotating the photoreceptor 101. , On their perimeter,
A unit 107 to which the image exposure means 105 and the surface potential measuring means 106 are attached is arranged. In addition, the defect detection means 108 is arranged at a position close to the surface of the photoconductor 101 and not interfering with the movement of the unit 107.

The charging means 103 is a long type charging means for charging the surface of the photosensitive member 101 over substantially the entire area.

The pre-exposure means 104 is arranged upstream of the charging means 103 in the rotation direction X of the photosensitive member 101.

The image exposing means 105 and the surface potential measuring means 106 can be attached at arbitrary angular positions of the unit 107, and the photosensitive member 101 can be also positioned in the vertical direction.
It can be attached at any position according to the diameter of the.

The unit 107 is connected to the moving means 109 by a screw shaft so that it can move in the generatrix direction of the photoconductor 101.

The defect detecting means 108 is connected to the moving means 110 by a screw shaft, and is configured to be freely movable in the generatrix direction of the photoconductor 101, including the case where it intersects with the unit 107.

The moving means 109 of the unit 107 and the moving means 110 of the defect detecting means 108 can be driven independently of each other. By these moving means, the photoconductor 101
The characteristics of the photoconductor can be measured at any position in the generatrix direction of the
The unit 107 and the defect detecting means 108 can be moved to the outside of the range of the photoconductor 101 so as not to scratch 01.

Pre-exposure means 104 and image exposure means 105
Is composed of an LED type exposure means.

The pre-exposure unit 104 and / or the image exposure unit 105 is configured to irradiate the photosensitive member 101 with light from a light source whose wavelength is variable as well as the exposure amount, using a lens or an optical fiber. It may be. In this case, as the light source having a variable wavelength, a light source such as a halogen lamp capable of dispersing analog light with a diffraction grating or a filter, a laser light source having a variable oscillation wavelength, or the like can be used.

Further, the pre-exposure means 104 and / or the image exposure means 105, as shown in FIG. 2, arranges a plurality of LEDs 202 having different emission wavelengths on the substrate 201,
The relative position of the ED 202 with respect to the opening 203 is set to the substrate 20.
It may be configured to move by one rotation. In this configuration, an LED having a desired emission wavelength is selected from the plurality of LEDs 202, and the selected LED is moved to the opening 203 to change the wavelength of the light beam 204.

As is apparent from FIG. 1, the photoconductor characteristic evaluation apparatus of the present invention comprises a unit 107 for evaluating the potential characteristic of the photoconductor 101 and a defect detection means 108 for detecting a defect of the photoconductor 101. The unit 101 and the defect detecting means 108 can be moved to different positions in the generatrix direction of 101, and the measuring operation can be performed simultaneously.

Generally, in order to detect a defect of the photoconductor, it is necessary to inspect almost the entire surface of the photoconductor. Regarding the potential characteristic, the potential in the photoconductor bus direction is estimated by measuring at several points in the photoconductor bus direction. You can grasp the unevenness.

Therefore, in the photoconductor characteristic evaluation apparatus shown in FIG. 1, in the unit 107, the potential characteristic of the photoconductor 101 is measured at an appropriate position in the generatrix direction of the photoconductor 101, and at the same time, the defect detection means 108. In the above, by detecting the defect of the photoconductor 101 at a position different from the unit 107 in the photoconductor bus direction, it is possible to evaluate the potential characteristic of the photoconductor 101 and the defect detection at the same time.

A plurality of units 107 and / or defect detecting means 108 may be arranged as shown in FIG. In this case, the moving means 109 of the unit 107 and / or
Alternatively, a plurality of moving means 110 of the defect detecting means 108 are arranged corresponding to the unit 107 and / or the defect detecting means 108, and each of them can be driven independently, so that the evaluation speed and the degree of freedom of the measurement position can be increased. Can be increased.

4A and 4B are schematic diagrams showing an example of the structure of the defect detecting means 108. FIG. 4A is a front view, and FIG. 4B is a sectional view of FIG. . Note that FIG.
1A and FIG. 4B are respectively FIG. 1A and FIG.
The figure seen from the same direction as (b) is shown.

As shown in FIG. 4, the defect detecting means 108 is
At least one detection electrode 401 and a support 402 that supports the detection electrode 401 are provided.

The detection electrode 401 has a Z-axis when the rotation direction of the photoconductor 101 is the X-axis, the normal direction of the surface of the photoconductor 101 is the Y-axis, and the direction perpendicular to the X-axis and the Y-axis is the Z-axis. It is placed in parallel with.

Further, the detection electrode 401 has a shape in which a cross section of a plane perpendicular to the surface of the photoconductor 101 and parallel to the rotation direction of the photoconductor 101 has no edge. Specifically, the cross-sectional shape of the detection electrode 401 is a perfect circle shape, an elliptical shape, or three arcs are connected by a radius,
One of the arcs has a shape that faces the surface of the photoconductor 101.

Further, the detection electrode 401 is connected to the circuit element 404 by a conductive wire 403.

When the photoconductor 101 rotates and relative movement occurs between the detection electrode 401 and the surface of the photoconductor 101, a minute change amount of the surface potential of the photoconductor 101 is dV, and a relative movement speed is dx / dt. Then, the detection electrode 401 has dV / dt = (dV / dx)
・ An induced current proportional to (dx / xt) is generated.

Therefore, when a minute defect such as a spherical protrusion exists on the photoconductor 101, the defect can be detected as an induced current. In the photoconductor characteristic evaluation device of the present invention, since the relative movement speed can be set arbitrarily, the detected induced current includes information on the slope of the surface potential. By analyzing this information, the photoconductor 1
The size and number of defects on the surface of No. 01 can be known.

Here, an experiment for actually detecting the surface defects of the photoconductor using the photoconductor characteristic evaluation apparatus shown in FIG. 1 was conducted. The result is shown in FIG.

FIG. 5A shows the waveform of the detection signal, and FIG. 5B shows the waveform of the surface potential distribution of the photosensitive member after the data of FIG. 5A is integrated and analyzed. Shows.

As shown in FIG. 5A, the time Δt from the time when the intensity of the signal from the detected defective portion becomes the minimum to the time when it becomes the maximum is calculated, and the relation between this Δt and the relative moving speed is calculated. Based on this, the size of the detected defect can be determined.

In addition, as shown in FIG.
It is also possible to determine the size of the detected defect by the integral analysis of the detection signal waveform of (a) to obtain the surface potential distribution and the half value width of this surface potential distribution.

In the analysis method of this embodiment, the width of the detection electrode 401 in the relative movement direction, that is, the photoconductor 101
The width in the circumferential direction of is required to be smaller than the width of the potential changing portion of the defective portion to be measured.

Further, the detection electrode 401 can be formed by using a conductive wire. The diameter of the wire used in this case greatly affects the detection resolution. Although it is basically desirable for the wire diameter to be small, there is a lower limit to the wire diameter because reducing the wire diameter lowers the signal strength. Therefore, it is desirable that the wire diameter be in the range of φ1 to 500 μm, preferably in the range of φ10 to 100 μm.

The length of the detection electrode 401 in the direction transverse to the relative movement direction, that is, the length of the photoconductor 101 in the generatrix direction determines the strength of the detected signal. When the length of the detection electrode 401 in the generatrix direction of the photoconductor 101 is increased, the signal strength increases, but the linearity and parallelism of the wires are easily deteriorated, and the resolution is easily deteriorated. Therefore, the length of the detection electrode 401 in the direction transverse to the relative movement direction is preferably within the range of 0.2 to 10 mm. In this case, as shown in FIG. 4, the detection electrode 401 is arranged so as to be parallel to the surface of the photoconductor and orthogonal to the relative movement direction.

FIG. 6 is a schematic view showing another embodiment of the photoconductor characteristic evaluation apparatus of the present invention.

The photoconductor characteristic evaluation apparatus shown in FIG. 6 is different from the photoconductor characteristic evaluation apparatus shown in FIG. 3 in the structure of the unit 107.

That is, the photoreceptor characteristic evaluation apparatus shown in FIG.
The plurality of units 107 are not provided with the moving means 109 for moving the plurality of units 107 in the generatrix direction of the photoconductor 101.
Is fixed relative to the generatrix direction of the photoconductor 101.

Although FIG. 6 shows an example in which three units 107 are arranged, the unit 1 may be further added if necessary.
The number of 07 can be increased.

Further, in the photoconductor characteristic evaluation apparatus shown in FIG. 6, the defect detecting means 108 is used as the photoconductor 10 at the time of defect detection.
When scanning along the bus line direction of unit 1, the unit 107
There is a time when it overlaps with. At this time, the measurement operation of the potential characteristic in the unit 107 is temporarily suspended,
Prioritizing the defect detection operation in the defect detection means 108,
After the defect detection unit 108 scans out of the range of the unit 107, the measurement operation of the potential characteristic in the unit 107 may be restarted.

FIG. 7 is a schematic view showing another embodiment of the photoconductor characteristic evaluation apparatus of the present invention, which is a view seen from the front.

The photoconductor characteristic evaluation apparatus shown in FIG. 7 is different from the photoconductor characteristic evaluation apparatus shown in FIG.
8 is different in configuration.

That is, the photoconductor characteristic evaluation apparatus shown in FIG.
The moving unit 110 for moving the defect detecting unit 108 in the generatrix direction of the photoconductor 101 is not provided, and the detection electrode 401 (see FIG. 4) is arranged over the entire region of the photoconductor 101 in the generatrix direction.

In the photoconductor characteristic evaluation apparatus shown in FIG. 7, similar to the photoconductor characteristic evaluation apparatus shown in FIG. 6, there is a time in which the defect detection means 108 and the unit 107 overlap, but in this case, At the place where the potential characteristic is measured by the unit 107, the defect detecting operation in the defect detecting means 108 is temporarily suspended, the measurement of the potential characteristic at that place is completed, and the unit 107 is suspended after moving to another place. It suffices to restart the defect detection operation of the defect detection means 108 that has been used.

8A and 8B are schematic views showing another embodiment of the photoconductor characteristic evaluation apparatus of the present invention. FIG. 8A is a front view, and FIG. 8B is a right or left view of FIG. 8A. FIG.

In the photoconductor characteristic evaluation apparatus shown in FIG. 8, the charging unit 803, the pre-exposure unit 804, the image exposure unit 105, and the surface potential measuring unit 106 are provided on the outer periphery of the cylindrical photoconductor 101 and the rotating unit 102. The attached unit 807 is arranged. In addition, the defect detection unit 808 is arranged at a position close to the surface of the photoconductor 101 and does not interfere with the movement of the unit 807.

The charging means 803 is not a long type charging means for charging almost the entire area of the photosensitive member 101, but a short type charging means for charging only a range necessary for measuring potential characteristics. In FIG. 8, a corotron charger is used as the charging unit 803.

Further, the charging means 803 and the image exposure means 10
5 and the surface potential measuring means 106 can be attached at arbitrary angular positions of the unit 807, and can also be attached at arbitrary positions according to the diameter of the photoconductor 101 regarding the vertical position.

The unit 807 is connected to the moving means 109 by a screw shaft so that it can move in the generatrix direction of the photoconductor 101.

The defect detecting means 808 comprises a defect detecting charging means 811 and a defect detecting section 812. Further, a charge eliminating means (not shown) is provided on the upstream side of the defect detecting charging means 811 in the rotation direction X of the photoconductor 101. May be provided. The defect detection unit 812 includes the detection electrode as described with reference to FIG.

The defect detecting means 808 is connected to the moving means 110 by means of a screw shaft, and is connected to the unit 807.
The structure is such that it can freely move in the generatrix direction of the photoconductor 101, including the case where it intersects with.

The moving means 109 of the unit 807 and the moving means 110 of the defect detecting means 108 can be driven independently of each other. By these moving means, the photoconductor 101
The characteristics of the photoconductor can be measured at any position in the generatrix direction of the
The unit 807 and the defect detection unit 808 can be moved to the outside of the range of the photoconductor 101 so as not to scratch 01.

Pre-exposure means 804 and image exposure means 105
Is configured to irradiate the photoconductor 101 with light from a light source having a variable wavelength as well as an exposure amount, using a lens, an optical fiber, or the like. In this case, as the light source having a variable wavelength, a light source such as a halogen lamp capable of dispersing analog light with a diffraction grating or a filter, a laser light source having a variable oscillation wavelength, or the like can be used.

As shown in FIG. 2, the pre-exposure means 804 and / or the image exposure means 105 arranges a plurality of LEDs 202 having different emission wavelengths on the substrate 201,
The relative position of the ED 202 with respect to the opening 203 is set to the substrate 20.
It may be configured to move by one rotation. Of course, the LED type exposure means as shown in FIG. 1B may be used.

As is apparent from FIG. 8, the photoconductor characteristic evaluation apparatus of the present invention comprises a unit 807 for evaluating the potential characteristic of the photoconductor 101 and a defect detection means 808 for detecting a defect of the photoconductor 101. 101 can be moved to different positions in the generatrix direction, and the unit 807
The defect detecting means 108 and the defect detecting means 108 can simultaneously perform the measurement operation.

Generally, in order to detect a defect of the photoconductor, it is necessary to inspect almost the entire surface of the photoconductor. However, regarding the potential characteristic of the photoconductor, it is possible to measure the photoconductor bus line at several points in the photoconductor bus line direction. The potential unevenness in the direction can be grasped.

Therefore, in the photoconductor characteristic evaluation apparatus shown in FIG. 8, the unit 807 measures the potential characteristic of the photoconductor 101 at an appropriate position in the generatrix direction of the photoconductor 101, and at the same time, the defect detecting means 808. In the above, by detecting the defect of the photoconductor 101 at a position different from the unit 807 in the photoconductor bus direction, it is possible to evaluate the potential characteristic of the photoconductor 101 and the defect detection at the same time.

Further, a plurality of units 807 and / or defect detection means 808 may be arranged as shown in FIG. In this case, the moving means 109 of the unit 807 and / or
Alternatively, a plurality of moving means 109 of the defect detecting means 808 are arranged corresponding to the unit 807 and / or the defect detecting means 808, and each of them can be driven independently, so that the speed of evaluation and the degree of freedom of measurement position can be increased. Can be increased.

FIG. 10 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device of the present invention.

The photosensitive member characteristic evaluation apparatus shown in FIG.
For the photoconductor characteristic evaluation device shown in FIG.
The configuration regarding is different.

That is, the photoconductor characteristic evaluation apparatus shown in FIG. 10 does not include the moving means 109 for moving the plurality of units 807 in the generatrix direction of the photoconductor 101, and does not include the plurality of units 8.
It is configured such that 07 is relatively fixed to the photoconductor 101.

Although FIG. 10 shows an example in which three units 807 are arranged, the number of units 807 can be further increased if necessary.

Further, in the photoconductor characteristic evaluation apparatus shown in FIG. 10, the defect detection means 808 is used as the photoconductor 1 at the time of defect detection.
When scanning along the 01 bus line direction, the unit 80
There is a time when it overlaps with 7. At this time, the potential characteristic measuring operation in the unit 807 is temporarily suspended, and the defect detecting operation in the defect detecting means 808 is prioritized.
After the defect detection unit 808 scans out of the range of the unit 807, the measurement operation of the potential characteristic in the unit 807 may be restarted.

Here, an experiment was carried out to measure the charging unevenness of the photoconductor 101 in the generatrix direction using the photoconductor characteristic evaluation apparatus shown in FIG. The result is shown in FIG.

In FIG. 11, the electrophotographic characteristic apparatus shown in FIG. 8 is used, the various conditions in the charging step are kept constant, the measurement position in the generatrix direction of the photoconductor 101 is changed, and the surface potential of the photoconductor 101 is changed. It is the result of measurement. Note that the position of the photoconductor 101 in the generatrix direction is 0 at the center position of the photoconductor 101.
cm, and the distance from the center position is expressed as plus or minus.

As is apparent from FIG. 11, by using the photoconductor characteristic evaluation apparatus of the present invention, it is possible to evaluate the charging characteristic of the photoconductor for each location in the photoconductor bus direction. Further, as shown in FIG. 9 and FIG. 10, if the measurement is performed by using the photoconductor characteristic evaluation device including the plurality of units 807, the same measurement result can be obtained in a shorter time.

Next, using the photoconductor characteristic evaluation apparatus shown in FIG. 8, the charging means 80 in the bus line direction of the photoconductor 101 is used.
An experiment was conducted on the ability to detect the difference in the charging characteristics of the photoconductor 101 by changing the effective charging range of No. 3. The result is shown in FIG.

FIG. 12A shows the charging characteristic for each position of the photoconductor 101 in the generatrix direction when the effective charging range of the charging means 803 is changed. The photoconductor 10
The center line position of the photoconductor 101 is 0 cm.
And the distance from the center position is expressed as plus or minus.

In the experiment, the voltage applied to the charging means 803 was adjusted so that the surface potential at the 0 cm position of the photoconductor 101 was 450 V, and only the measurement position in the generatrix direction of the photoconductor 101 was changed under the same conditions as at that time. Then, the surface potential of the photoconductor 101 was measured at each position.

In FIG. 12B, the difference between the maximum value and the minimum value of each data in FIG. 12A is taken as the charging bus line direction unevenness of the photoconductor 101 and plotted against the effective charging range of the charging means 803. The results are shown.

The data shown in FIGS. 12 (a) and 12 (b) are the data obtained when the charging means 803 were manufactured and tested so that the effective charging range of the charging means 803 would be each length. However, using a long type charging means,
Similar results were obtained when the effective charging range of the charging device was adjusted by insulating unnecessary parts of the long charging device.

As is apparent from FIG. 12, the charging means 80
As the effective charging range of 3 becomes shorter, the charging unevenness in the generatrix direction of the photoconductor 101 becomes larger. From this result, it is understood that the shorter the effective charging range of the charging unit 803 is, the more noticeable the difference in actual force with respect to the charging capability of each position of the photoconductor 101 in the bus line direction can be detected. This is the charging means 80.
This is because when the effective charging range of 3 is long, the charging is performed so that the potentials are averaged within the charging range at the time of charging, and it becomes difficult to see the characteristics of the photoconductor 101 for each position in the generatrix direction. Conceivable.

When the photoconductor characteristic evaluation device of the present invention is used on a daily basis, the charging means 803 may be inclined with respect to the photoconductor 101 or may be partially soiled. Due to these factors, uniform charging is possible. May not be obtained. It is not preferable that the evaluation result fluctuates significantly due to that influence,
In order to minimize such an influence as much as possible, the charging means 8
It is preferable that the effective charging range of 03 is short.

From the above results, in order to more accurately detect the actual force difference of the photoconductor 101 in relation to the charging bus line direction, the charging means 803 in the photoconductor 101 bus line direction is detected.
The effective charging range of is preferably 15 cm or less.
However, the effective charging range of the charging means 803 is 2 cm.
If the length is shorter than this, the charging itself becomes very unstable and it becomes difficult to measure the potential. Therefore, it is more preferable that the effective charging range of the charging unit 803 is 2 cm or more and 15 cm or less.

Next, the dependency of the charging characteristic of the photosensitive member 101 on the pre-exposure wavelength of the pre-exposure means 804 was evaluated using the photosensitive member characteristic evaluation apparatus shown in FIG. The result is shown in Figure 1.
3 shows. Further, FIG. 14 shows another evaluation result of the dependency of the charging characteristic of the photoconductor 101 on the pre-exposure wavelength of the pre-exposure unit 804.

FIG. 13 shows the surface of the photoconductor 101 when the exposure wavelength of the pre-exposure means 804 is changed under the conditions that the conditions in the charging step are constant and the exposure amount of the pre-exposure means 804 is constant. The measurement result of the electric potential is shown.

FIG. 14A shows the measurement result of the surface potential of the photosensitive member 101 when the exposure amount is changed for each pre-exposure wavelength of the pre-exposure means 804. Note that FIG.
The data of 4 (a) is for the photoconductor 10 after the charging process is started.
It is the data which measured the electric potential of the 1st rotation of 1. Photoconductor 1
The reason why the potential of the first rotation of 01 was measured is to obtain data when the pre-exposure light amount is "0". As another method, the potential when each light amount is stable may be measured and the data may be extrapolated to obtain the data when the pre-exposure light amount is “0”.

FIG. 14B shows the potential of the photosensitive member surface when the pre-exposure light amount is “0” in FIG. 14A and a certain reference light amount (in FIG. 14A, 3 μJ / cm 2 as an example). ²
And The results are plotted against the wavelength with the difference between the potential of the surface of the photoconductor and the potential of the photoconductor as the pre-exposure memory.

By carrying out the measurement shown in FIGS. 13 and 14 in this manner, the characteristics of the photosensitive member 101 such as how much the pre-exposure wavelength and the amount of light of the pre-exposure means 804 affect the charging process are evaluated. Is possible. This evaluation method is not only compatible with the developed photoconductor and the electrophotographic apparatus equipped with the photoconductor, but also with regard to how various phenomena caused by pre-exposure irradiation affect latent image formation. It is an evaluation method that enables correct understanding, and is a very important evaluation method when designing a comprehensively excellent photoconductor and electrophotographic process.

Next, by using the photoconductor characteristic evaluation apparatus shown in FIG. 8 and using a corotron charger as the charging means 803 and a scorotron charger (not shown), Experiments were conducted on how different the ability to detect the difference in charging characteristics was. Figure 15 shows the result.
Shown in.

In the experiment, a corotron charger and a scorotron charger having an effective charging range of 6 cm were used as the charging means 803, and the applied voltage of the charging means 803 was adjusted so that the surface potential of the photosensitive member 101 at the 0 cm position was 450 V. Was adjusted, and only the measurement position in the generatrix direction of the photoconductor 101 was changed under the same conditions as that time, and the surface potential of the photoconductor 101 was measured at each position. Regarding the position of the photoconductor 101 in the generatrix direction, the center position of the photoconductor 101 is 0 cm,
The distance from the center position is expressed by plus and minus.

As is apparent from FIG. 15, the charging means 80
When the corotron charger is used as No. 3, the charging unevenness in the generatrix direction of the photoconductor 101 is larger than that when the scorotron charger is used. From this result, it can be seen that by using a corotron charger as the charging unit 803, the actual difference in the charging characteristics of the photoconductor 101 can be detected more significantly.

Next, a specific method for evaluating the charging characteristics of the photoconductor will be described with reference to FIG.

FIGS. 16 (a) to 16 (c) show the relationship between the surface potential V of the photoconductor and the so-called QV characteristic when the surface charge Q of the photoconductor is changed by using the apparatus shown in FIG. The measurement results are shown. Although it is difficult to directly measure the surface charge Q on the photoreceptor, as shown in FIG. 16, (a) a current flowing through the charger in the charging step, (b) a current flowing in the photoreceptor direction in the charging step, ( c) By measuring the correlation between the voltage applied to the charger and the surface potential of the photoconductor in the charging step, it can be seen that the characteristic corresponding to the QV characteristic can be evaluated as a substitute.

FIG. 16D is a schematic diagram showing an example in which the quality of the charging characteristics of the photoconductor is evaluated based on the data obtained by these measurements. The vertical axis represents the surface potential of the photoconductor and the horizontal axis represents the surface charge of the photoconductor. However, as described above, it is difficult to directly measure the surface charge of the photoconductor. ) To (c), the current value flowing through the charging device, the current value flowing in the photoconductor direction, the voltage applied to the charging device, and other parameters in the charging process can be used as a substitute plot. These values may differ not only depending on the setting conditions in the charging process, but also in units themselves depending on the parameters used. Therefore, the horizontal axis in FIG.
It was expressed as [au] (= Arbitrary Unit, arbitrary unit).

As shown in FIG. 16D, the Q of the photoconductor is
The −V characteristic can be divided into two regions with a certain threshold as a boundary. In the following description, the photoconductor 10 exceeding the threshold is exceeded.
A region where the surface potential of 1 increases linearly is called a linear region, and a region below the threshold value is called a transient region.

The QV characteristic of the photosensitive member 101 is shown in FIG.
In the case shown in (d), the transient region is a process in which carriers remaining in the film of the photoreceptor 101 before charging are recombined or are accelerated by the electric field from the charging unit 803 and disappear. Presumed to be. Further, it is assumed that the linear region is a process in which the photoconductor 101 is charged by the electric charge from the charging unit 803. Therefore, the charging characteristics of the photoconductor 101 can be evaluated by obtaining the threshold value or the inclination in the linear region. Further, with respect to the surface charge of the photoconductor 101, a reference value (in FIG. 16D, set to 75 as an example).
It is also possible to set, and to evaluate the charging characteristics of the photoconductor by the surface potential at that time.

Next, a specific method for evaluating the time change amount of the surface potential of the photoconductor (hereinafter referred to as the potential shift characteristic) will be described with reference to FIG.

In FIG. 17, the photoconductor characteristic evaluation apparatus shown in FIG. 8 is used, the photoconductor 101 is rotated, and the pre-exposure means 80 is used.
4, the pre-exposure is performed, the charging means 803 starts charging, and the surface potential measuring means 10 starts from the time when the charging is started.
6 readings are recorded. Note that Δt is the time required for the surface of the photoconductor 101 to move from the charging unit 803 to the surface potential measuring unit 106.

By performing the measurement as shown in FIG. 17, it is possible to observe that the photosensitive member 101 is charged every time it rotates, and the surface potential gradually stabilizes by repeated rotation. At this time, as the surface potential of the photoconductor 101, the potential of the first round (or the second round) from the start of charging,
The potential shift characteristic can be evaluated by measuring the potential in a sufficiently stable state and comparing the measured values.

Next, a specific method for evaluating the photosensitivity of the photoconductor will be described with reference to FIG.

FIG. 18A shows the surface potential V of the photoconductor 101 when the exposure amount E of the post-charging exposure in the image exposure means 105 is changed by using the photoconductor characteristic evaluation apparatus shown in FIG. The relationship, that is, the measurement result of the so-called EV characteristic is shown.

When an a-Si photosensitive member is used as the photosensitive member 101, as shown in FIG. 18A, an EV characteristic is obtained in which the surface potential V decreases linearly with the exposure amount E. .
Using this E-V characteristic, as shown in FIG. 18 (b), a method for obtaining the inclination in a linear region, a reference light amount (in FIG. 18 (b), 0.2 μJ / c as an example)
It was set to m ² . ) Is used to determine the surface potential or the amount of potential attenuation, or a method is used to determine the amount of exposure when the reference contrast potential (50 V in FIG. 18B) is obtained. The photosensitive characteristics of 101 can be evaluated. Further, in the method of obtaining the surface potential or the amount of potential attenuation when the reference light amount is exposed, by setting the reference light amount to a sufficiently strong light amount, the photosensitive characteristics such as the residual potential of the photoconductor 101 can be evaluated.

Next, a specific method for evaluating the exposure wavelength dependency of the photosensitive characteristic of the photosensitive member, that is, the so-called spectral characteristic will be described with reference to FIG.

Using the photoconductor characteristic evaluation apparatus shown in FIG. 8, while changing the wavelength of post-charging exposure in the image exposure means 105, the photoconductor characteristic of the photoconductor 101 is changed for each exposure wavelength by the method described in FIG. FIG. 19 is obtained by measuring and plotting this measured value with respect to the exposure wavelength. The photosensitive characteristics for each exposure wavelength are necessary to obtain the slope of the approximate straight line of the measurement data, the potential attenuation amount when the reference light amount is applied, and the reference contrast potential, as shown in FIG. 18B. It can be represented by the amount of exposure.

By performing the measurement shown in FIG. 19 in this manner, the spectral characteristics of the photoconductor 101 can be evaluated under the same conditions as in the electrophotographic process. This evaluation method is
It is possible not only to understand the compatibility between the photoconductor to be developed and the electrophotographic device equipped with it, but also to correctly understand how various phenomena caused by light irradiation affect latent image formation. It is an evaluation method and is a very important evaluation method when designing a comprehensively excellent photoconductor and electrophotographic process.

FIG. 20 is a schematic view showing another embodiment of the photoconductor characteristic evaluation apparatus of the present invention.

The photoconductor characteristic evaluation apparatus shown in FIG.
In contrast to the photoconductor characteristic evaluation device shown in (b), the second surface potential measuring means 2013, the surface temperature measuring means 2014 for measuring the surface temperature of the photoconductor 101, and the time when the photoconductor 101 is rotating. Eccentricity measuring means 20 for measuring the eccentricity of
15 and 15 are further attached to the unit 807.

The surface potential measuring means 2013, the surface temperature measuring means 2014 and the eccentricity amount measuring means 2015 are not always necessary, and may be attached or removed as necessary.

By using the photoconductor characteristic evaluation apparatus shown in FIG. 20 and comparing the surface potential measurement data by the surface potential means 106 and 2013, the characteristic relating to the charge retention ability of the photoconductor 101 (hereinafter referred to as dark decay characteristic It is possible to evaluate The dark decay characteristic can be measured if two or more surface potential measuring means are attached to the unit 807. For example, the dark decay characteristics can be measured immediately before the pre-exposure means 804 and immediately before the charging means 803. Even if the surface potential measuring means 4 is arranged, the dark decay characteristic can be measured and effective data can be obtained.

Next, a specific method for evaluating the optical memory characteristics of the photoconductor will be described with reference to FIG.

First, a method for measuring the optical memory characteristics shown in FIG. 21A will be described.

The upper diagram of FIG. 21 (a) uses the photoconductor characteristic evaluation apparatus shown in FIG. 20 to rotate the photoconductor 101,
Immediately after passing through the charging means 803, the image exposure means 105 causes the photoreceptor 1 to have a predetermined surface potential so that the photoreceptor 101 has a predetermined surface potential.
01 is exposed with the light amount E1 for t1 seconds, and then with the light amount E2 for t
The figure shows a change in the surface potential of the photoconductor 101 when the electrophotographic process of exposing for 2 seconds and then exposing for 3 seconds with the light amount E3 is repeated n times (n: natural number). The light amount E1 is preferably a light amount for obtaining the contrast potential required in the electrophotographic process, and the light amount E2 needs to be a light amount smaller than the light amount E1 and may be E2 = 0. Further, the light amount E3 corresponds to the sheet interval during the actual electrophotographic process, and can be set to various values depending on the assumed electrophotographic process conditions. When this process is performed, the ghost of the portion exposed by the light amount E1 on the photoconductor 101 appears one lap after that, so the potential from T (T; rotation period) seconds after the process start time to T + t1 second is measured. , And the measured potential data is Vgn.

The lower part of FIG. 21A shows the change in the surface potential of the photosensitive member 101 when the process shown in the upper part is changed to E1 ′ only for the first exposure amount. The light amount E1 ′ needs to be equal to or less than the light amount E2, and may be E1 ′ = 0. Then, as in the case of the above figure, the process start time T (T;
Rotation cycle) Measure the potential from after 2 seconds to T + t 1 seconds,
The measured potential data is set to Vgn '.

The potential data Vg thus obtained
The optical memory characteristics of the photoconductor 101 can be evaluated by comparing n and Vgn ′ and calculating the difference and ratio. This evaluation method is an evaluation method capable of simulating the conditions in which a chart for ghost evaluation is displayed using an actual electrophotographic apparatus, that is, in the stage where there is no electrophotographic apparatus to output. Is also an epoch-making evaluation method that makes it possible to evaluate the goodness or badness of the rendered results.

Next, a method of measuring the optical memory characteristics shown in FIG. 21B will be described.

The upper diagram of FIG. 21 (b) uses the photoconductor characteristic evaluation apparatus shown in FIG.
Immediately after passing through the charging means 803, the image exposure means 105 causes the photoreceptor 1 to have a predetermined surface potential so that the photoreceptor 101 has a predetermined surface potential.
01 represents the change in the surface potential of the photoconductor 101 when n is exposed for n rotations (n; natural number) with the light amount E1 and then for one rotation with the light amount E2. The amount of light E1
Is preferably a light amount for obtaining a contrast potential required in the electrophotographic process, and the light amount E2 needs to be smaller than the light amount E1 and may be E2 = 0. When performing this process, the photoreceptor 101
Since the ghost of the portion exposed with the above light amount E1 appears after one round, the potential when exposed with the light amount E2 is measured, and the measured potential data is set to Vg.

The lower part of FIG. 21B shows the change in the surface potential of the photosensitive member 101 when the process shown in the upper part is changed to E1 ′ only for the first exposure amount. The light amount E1 ′ needs to be equal to or less than the light amount E2, and may be E1 ′ = 0. Then, as in the case of the above figure, the potential at the time of exposure with the light amount E2 is measured, and the measured potential data is set to Vg ′.

The potential data Vg thus obtained,
The optical memory characteristics of the photoconductor 101 can be evaluated by comparing Vg ′ with each other and calculating the difference or ratio. This evaluation method is different from the condition in which a chart for ghost evaluation is displayed using an actual electrophotographic device, but it is an evaluation method that can evaluate the ability of the photoconductor with regard to the optical memory with higher accuracy. is there.

Next, a specific method for evaluating the dependence of various characteristics of the photosensitive member on temperature will be described.

Using the photoconductor characteristic evaluation apparatus shown in FIG. 20, while changing the surface temperature of the photoconductor 101 by means (not shown) for heating or / and cooling the photoconductor 101, By measuring the properties, it is possible to measure the dependence of those properties on temperature. FIG. 22 shows, as an example thereof, the results of evaluating the temperature dependence of the charging characteristics of the photoconductor.

FIG. 22 shows the pre-exposure means 8 as an experimental condition.
A heater (not shown) disposed inside the photoconductor 101, with the irradiation conditions of No. 04 and various conditions in the charging process being constant.
The results of measuring the surface potential and the surface temperature almost simultaneously while changing the surface temperature of the photoconductor 101 are shown by. Here, a non-contact infrared temperature sensor as shown in FIG. 20 is used as the surface temperature measuring means 2014, but the same result can be obtained when a contact type temperature sensor is used. Further, as a means for changing the surface temperature of the photoconductor 101, an infrared heating means or a heating means for bringing a heat source into contact with the photoconductor 101 may be used. Alternatively, after the photoconductor 101 is heated once, the photoconductor characteristics may be evaluated while lowering the surface temperature of the photoconductor 101 by using a cooling unit such as a blowing unit.

In FIG. 22, the charging characteristic of the photoconductor 101 is a characteristic that changes substantially linearly with respect to the surface temperature, but the charging characteristic of the photoconductor changes in a curve with respect to the surface temperature. It may be a characteristic. Therefore, it is very important in designing the characteristics of the photoconductor to grasp the temperature dependence of the photoconductor's charging properties, photosensitivity properties, potential shift properties, dark decay properties, optical memory properties, etc. as described above. Is.

As another method for evaluating the temperature dependence of various characteristics of the photoconductor, the photoconductor is not heated (that is,
The surface temperature of the photoconductor and various characteristics of the photoconductor are measured with the photoconductor surface being at approximately room temperature) and the photoconductor being heated.
A method of evaluating the temperature characteristics of the photoconductor by comparing them may be used.

As described above, the apparatus for evaluating the characteristics of the photoconductor of the present invention can measure the unevenness of the charging characteristics of the photoconductor in the generatrix direction (see the description of FIG. 11). By measuring various characteristics such as photosensitivity characteristics, potential shift characteristics, dark decay characteristics, and optical memory characteristics at multiple positions in the photoconductor busbar direction, it is possible to measure the photoconductor busbar direction distribution for these characteristics as well. become.

Similarly, in the photoconductor characteristic evaluation apparatus of the present invention, it is possible to evaluate the characteristic unevenness of the photoconductor in the circumferential direction. Characteristic unevenness in the circumferential direction of the photoconductor is evaluated by reading the maximum value and the minimum value of the data for one round of the photoconductor when reading the output from the surface potential measuring means, and obtaining the difference between these values. You can

As the constitution for evaluating the characteristic unevenness in the circumferential direction of the photoconductor, for example, memory means such as an oscilloscope or digital multimeter having a data memory function for recording the output from the surface potential measuring means, A rotation detecting means for generating a signal when detecting the rotation of the body is provided, and the rotation of the photosensitive body and the operation of the memory means are synchronized by using the signal generated by the rotation detecting means. It is possible to measure the characteristic unevenness in more detail. Further, the rotation detecting means may not be provided and a signal relating to the rotation of the photoconductor may be obtained from the photoconductor rotating means.

FIG. 23 is a schematic view showing an example of the constitution of the rotation detecting means used in the photoconductor characteristic evaluation apparatus of the present invention.

In the configuration shown in FIG. 23A, the window 230
When the plate 2301 having 2 is rotated at the same angular velocity as the photoconductor, the window 2302 crosses the photosensor 2303 every time the photoconductor makes one revolution. Therefore, the photo sensor 2303 is turned on / off each time the photoconductor rotates once.
However, a pulse signal can be generated.

According to the same principle, in the structure shown in FIG. 23B, the rotating rod 2304 is rotated at the same angular velocity as the photosensitive member.
When 304 is rotated, the rotating rod 2304 crosses the photo sensor 2303 every time the photosensitive member makes one rotation. Therefore, the photo sensor 2303 is turned on / off every time the photoconductor rotates once, and a pulse signal can be generated.

Here, the signal obtained from the above-mentioned rotation detecting means or the rotating means of the photoconductor is used as a trigger signal of the above-mentioned memory means, and the memory means is operated in synchronization with the rotation of the photoconductor, FIG. 24 shows the result of examining the distribution of charging characteristics in the circumferential direction of the photoconductor.

FIG. 24 shows the results of measuring the surface potential at each circumferential position of the photoconductor 101 when the electrophotographic characteristic device shown in FIG. 8 is used and the various conditions in the charging process are kept constant. There is.

As is apparent from FIG. 24, by using the photoconductor characteristic evaluation apparatus of the present invention, it is possible to evaluate the photoconductor characteristics in detail for each location in the circumferential direction of the photoconductor.

Further, by combining and evaluating the generatrix direction distribution and the circumferential direction distribution of the photoconductor, it is possible to evaluate the location dependence on the entire surface of the photoconductor. FIG. 25 shows an example of the evaluation result.

FIG. 25 is a color-coded representation of the level of the surface potential of the photoconductor 101 when the electrophotographic characteristic apparatus shown in FIG. 8 is used and the various conditions in the charging process are kept constant. 25, the horizontal axis represents the position of the photoconductor 101 in the generatrix direction, and the vertical axis represents the position of the photoconductor 101 in the circumferential direction. The position of the photoconductor 101 in the generatrix direction is the photoconductor 1
The center position of 01 was 0 cm, and the distance from the center position was represented by plus and minus.

As shown in FIG. 25, by expressing the charging characteristics of the photoconductor 101 for each location of the photoconductor 101, it becomes possible to grasp the characteristic unevenness of the photoconductor at a glance.

[0165]

EXAMPLES Examples of the present invention will be described below, but the present invention is not limited to the examples described below.

(First Example) Using the photoreceptor characteristic evaluation apparatus shown in FIG. 20, the defect detection of the photoreceptor 101 and the potential characteristic were evaluated simultaneously.

Regarding defect detection, defect detection means 808
4 is used as the defect detection unit 812 of FIG. 4, a tungsten wire of φ30 μm is used as the wire, and the length of the photoconductor 101 in the generatrix direction is 2 m.
m. Such a defect detecting unit 808 is used as the photosensitive member 1.
Scanning was performed at a speed of 1 mm / sec in the direction of the No. 01 generatrix to measure the size of defects and the number of defects. Under these measurement conditions, the measurement time required for defect detection was about 6 minutes.
The results are shown in Table 1.

[0168]

[Table 1] Regarding the potential characteristics, a corotron charger having an effective charging range of 6 cm is used as the charging unit 803, and the photoreceptor 1
A heater for heating the photoconductor 101 was placed inside 01 for evaluation. The measurement conditions and the measurement routine regarding the potential characteristics are as follows.

First, as shown in FIG. 22, while the photoconductor 101 is being heated with the irradiation conditions of the pre-exposure means 804 and various conditions in the charging process being kept constant, the respective positions in the photoconductor generatrix direction. The surface potential was measured with, and the amount of change in the surface potential per unit temperature was calculated using the measured data to obtain the temperature characteristic.

Subsequently, the surface temperature of the photoconductor 101 is 42 ° C.
The following measurements were performed in a state where the temperature was constant at ± 1 ° C.

First, the effect of pre-charge exposure by the pre-exposure means 804 on the charging characteristics of the photoconductor 101 was measured. The measurement was performed by measuring the wavelength dependence of the pre-exposure memory by the method shown in FIG.
And the half width of the spectrum were determined. In the subsequent measurement, the irradiation condition of the pre-exposure means 804 is set to the wavelength of 680n.
m and the exposure dose was 3 μJ / cm ^{2 and} was constant. This was done to model an appropriate electrophotographic process, and it is possible to set any wavelength and exposure amount.

Next, the photosensitive member 101 is formed by the method shown in FIG.
The potential shift characteristic of was measured. As the charging condition at this time, the value of the charging current flowing through the charging unit 803 is 100 μA, and the difference between the surface potential of the photosensitive member 101 in the second rotation after the start of charging and the surface potential when it is sufficiently stable is referred to as potential shift. did.

Then, the photosensitive member 101 is formed by the method shown in FIG.
16D, the threshold value and the slope of the linear region are calculated and the reference value is set to 10 as shown in FIG.
The surface potential of the photoconductor 101 when 0 μA was defined as the charging ability. After that, the circumferential unevenness of the surface potential when the surface potential of the photoconductor 101 is adjusted to 450 V is defined as VD circumferential unevenness, and the output from the surface potential measuring means 106 and the output from the surface potential measuring means 2013 at that time. The difference between and is the dark decay.

Next, the photosensitive member 101 is formed by the method shown in FIG.
Was measured, and the peak wavelength of the sensitivity and the half width of the spectral sensitivity spectrum were calculated. In the subsequent measurement, the irradiation condition of the post-charging exposure in the image exposure unit 105 was kept constant at a wavelength of 650 nm. This was done to model an appropriate electrophotographic process, and it is possible to set any wavelength and exposure amount.

Then, the photosensitive member is formed by the method shown in FIG.
The EV characteristic of No. 101 was measured and illustrated in FIG.
Then, the slope of the straight line is calculated, and the reference light amount is 0.7 μJ /
cm ²And the surface potential of the photoconductor 101 is
Then, the reference contrast is Δ400 V (surface potential during exposure
The exposure amount at 50 V) was taken as the sensitivity. Also the criteria
Circumferential direction of surface potential under the condition that contrast can be obtained
The unevenness was defined as VL circumference unevenness.

Next, the optical memory characteristics of the photoconductor 101 were measured by the method shown in FIG. E1 in FIG. 21A is the same light quantity as the sensitivity obtained in the immediately preceding measurement, and E2
Is the amount of light to be E1 / 2, E3 and E1 ′ are zero, the optical memory measurement process described in FIG. 21 (a) is repeated 5 times, each potential data Vgn, Vgn ′ is calculated, and the maximum value thereof is calculated. As an optical memory.

The above characteristics were measured at each position in the generatrix direction of the photoconductor 101. In addition, the series of measurements were all performed automatically. The eccentricity measuring unit 2015 measures the eccentricity when the photoconductor 101 rotates, and when the eccentricity becomes larger than a certain reference value,
The evaluation was controlled so as to stop. This is to improve the reliability of the measurement result due to the influence of the eccentricity, particularly the measurement result of the characteristic relating to the circumferential characteristic. The above results are shown in Table 2.

[0178]

[Table 2] As is clear from Table 1 and Table 2, defect evaluation for detecting minute defects on the surface of the photoconductor, charging property, photosensitivity property, dark decay property, optical memory property by using the photoconductor property evaluation apparatus of the present invention It can be understood that various characteristics related to electrostatic latent image formation such as the above can be evaluated at the same time, and comprehensive evaluation of the photoconductor can be performed with a simple operation in a short time. In addition, since the evaluations are fully automatic and highly accurate measurement is possible, highly reliable and reproducible evaluation results can be obtained.

(Second Embodiment) Using the photoconductor characteristic evaluation apparatus shown in FIG. 6, the defect detection of the photoconductor 101 and the potential characteristic were evaluated simultaneously.

In this example, the evaluation was performed under the measurement conditions that imitated a certain electrophotographic apparatus, and the evaluation was performed based on the criterion of whether the photoconductor can be used in this electrophotographic apparatus. That is, an example using the photoreceptor characteristic evaluation apparatus of the present invention is shown as an inspection step before shipment of the photoreceptor.

As the defect detecting means 108, the wire type shown in FIG. 4 is used, and the wire has a diameter of 30 μm.
The length of the photoreceptor 101 in the generatrix direction was set to 2 mm using a tungsten wire of m. As shown in FIG. 6, two such defect detecting means 108 are arranged and the photoconductor 101
Scanning was performed at a speed of 1 mm / sec in the generatrix direction to measure the size and number of defects. Under these measurement conditions,
The measurement time required for defect detection was about 4 minutes. Table 3 shows a list of measurement conditions relating to potential characteristics used in this example.
Shown in.

[0182]

[Table 3] Under the measurement conditions shown in Table 3, the temperature characteristic of the photoconductor 101, potential shift, charging ability, dark decay, sensitivity, residual potential, V
The items of D unevenness, VL unevenness and optical memory were evaluated by the same method as in the first embodiment. For VD unevenness and VL unevenness, the difference between the maximum value and the minimum value in the range in which the potential is measured is defined as unevenness, and for other items,
The worst value among the data measured at three arbitrary points in the generatrix direction of the photoconductor 101 was selected. These evaluations were performed on 10 photoconductors produced by the same manufacturing recipe. The evaluation results are shown in Table 4. The criteria for surface defects are shown in Table 5. Those that meet all the items in Table 5 are OK
If there is any item that does not satisfy even one, it is shown as NG in Table 4.

[0183]

[Table 4]

[0184]

[Table 5] As is clear from Table 4, by using the photoconductor characteristic evaluation device of the present invention, defect evaluation for detecting microscopic defects of the photoconductor and electrostatic properties such as charging property, photosensitivity property, dark decay property, optical memory property, etc. It can be seen that various characteristics related to latent image formation can be evaluated at the same time, and comprehensive evaluation of the photoconductor can be performed with a simple operation in a short time.

In this embodiment, the number of units is three.
Since the photoconductor characteristic evaluation device arranged on the table is used, data relating to the photoconductor bus line direction unevenness can be obtained at one time, and therefore the evaluation can be completed in a shorter time.

[0186]

As described above, in the present invention,
Since it is possible to evaluate the potential characteristics of the photoconductor and the defect at the same time, the work required for the evaluation can be simplified compared to the conventional technology in which those evaluations were performed by different evaluation devices. Further, it is possible to obtain the effect that the comprehensive evaluation of the photoconductor can be completed in a short time. Also,
By shortening the work man-hours and tact at the time of evaluation,
The effect that the cost of the photoconductor can be reduced can be obtained.
In addition, since the potential characteristic evaluation and the defect evaluation of the photoconductor are performed fully automatically and highly accurate measurement is possible, it is possible to obtain a highly reliable and reproducible evaluation result. Is obtained.

Further, the use of the photoconductor characteristic evaluation device of the present invention as an evaluation device when developing a new photoconductor produces a great effect. In other words, even in the initial stage of development, where even a prototype of a new electrophotographic device has not been completed, it becomes possible to evaluate various characteristics under the same conditions as the completed electrophotographic device. It is possible to obtain an effect that the correlation between the film-forming prescription and the electrophotographic characteristics can be grasped with extremely high accuracy.

Further, with respect to the detection of defects of the photoconductor and the evaluation of the optical memory characteristics, conventionally, only the evaluation was carried out by actually producing an image using a prototype and visually evaluating the image. With respect to such evaluation as well, since highly accurate quantitative evaluation is possible, it is possible to design the characteristics of the photoconductor relating to image quality without a prototype. As a result, it becomes possible to determine the direction of development in the initial stage of development, and it is possible to obtain the effect of shortening the development period of a new photoconductor.

Furthermore, by arranging the exposing means on the upstream side or the downstream side of the charging means in the rotational direction of the photosensitive member, and measuring the spectral characteristics of pre-charge exposure and post-charge exposure, various phenomena caused by light irradiation are obtained. It is possible to evaluate the characteristics of the photoconductor, such as how the influence on the latent image formation. Therefore, not only is the compatibility of the developed photoconductor with the electrophotographic apparatus equipped with the photoconductor developed, but also the developability of the photoconductor to a succeeding model, or the photoconductor for a model currently being produced (for example, an analog model). It will be possible to make a comprehensive evaluation in consideration of the common use with the product and the common use with the photoconductor supplied as a service part of the model that has already been discontinued. As a result, the photoconductor characteristic evaluation device of the present invention plays an important role toward the development of a photoconductor that can be commonly used in many electrophotographic devices from analog to digital. As a result, the cost of the photoconductor can be reduced and the like.

[Brief description of drawings]

1A and 1B are schematic diagrams showing an embodiment of a photoreceptor characteristic evaluation apparatus of the present invention, where FIG. 1A is a front view and FIG. 1B is a sectional view of FIG. Is.

FIG. 2 is a schematic diagram showing a configuration example of an exposure unit used in the photoconductor characteristic evaluation apparatus of the present invention.

FIG. 3 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device of the present invention.

FIG. 4 is a schematic diagram showing a configuration example of a defect detection unit used in the photoconductor characteristic evaluation apparatus of the present invention.

FIG. 5 is a diagram showing an example of detection results obtained by detecting defects on the surface of the photoconductor using the photoconductor characteristic evaluation apparatus of the present invention;
(A) is a figure which shows the waveform of the detection signal from a defective part, (b)
FIG. 6 is a diagram showing a waveform after the data of (a) is integrated and analyzed.

FIG. 6 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device of the present invention.

FIG. 7 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device of the present invention.

FIG. 8 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device according to the present invention, in which (a) is a front view.
(B) is sectional drawing which looked at (a) from the right or the left.

FIG. 9 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device of the present invention.

FIG. 10 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device of the present invention.

FIG. 11 is a diagram showing an example of a measurement result obtained by measuring the distribution of charging characteristics of a photoconductor in the photoconductor bus direction using the photoconductor characteristic evaluation apparatus of the present invention.

FIG. 12 is a diagram showing an example of an evaluation result of evaluating the dependency of the charging characteristic of the photosensitive member on the effective charging range of the charging unit using the photosensitive member characteristic evaluation apparatus of the present invention, and FIG. Showing the measurement results obtained by measuring the distribution of the charging characteristics of the photosensitive member in the direction of the photoconductor bus for each effective charging range, and (b) shows the difference between the maximum value and the minimum value of each data in (a). It is the figure which plotted against the effective charging range of the charging means as bus-line direction unevenness.

FIG. 13 is a diagram showing an example of an evaluation result of evaluating the dependence of the charging characteristic of the photoconductor on the exposure wavelength of the pre-exposure means, using the photoconductor characteristic evaluation apparatus of the present invention.

FIG. 14 is a diagram showing another example of the evaluation results of evaluating the dependence of the charging characteristics of the photoconductor on the exposure wavelength of the pre-exposure means, using the photoconductor characteristic evaluation device of the present invention. The figure which evaluated the dependence of the charging characteristic of the photoconductor on the exposure light amount of the pre-exposure means, (b) is the figure which plotted the pre-exposure memory obtained from the data of (a) with respect to the pre-exposure wavelength of the pre-exposure means. is there.

FIG. 15 is a graph showing the distribution of the charging characteristics of the photoconductor in the direction of the photoconductor bus when the photoconductor characteristic evaluation device of the present invention is used and a corotron charger is used as the charging means and a scorotron charger is used. It is a figure which shows an example of the measured result of measurement.

FIG. 16 is a diagram for explaining a method for measuring the charging characteristic of the photoconductor, in which (a) uses the photoconductor characteristic evaluation apparatus of the present invention, and the total current flowing through the charging unit during the charging step and the photoconductor The figure which shows an example which measured the relationship of surface potential, (b) is the photoconductor characteristic evaluation apparatus of this invention is used, The electric current which flows into a photoconductor out of the total electric current which flows into a charging means at the time of a charging process, and the surface of a photoconductor The figure which shows an example which measured the relationship of an electric potential, (c) shows the example which measured the relationship between the voltage applied to a charging means at the time of a charging process, and the surface electric potential of a photoconductor using the photoconductor characteristic evaluation apparatus of this invention. FIG. 6D is a schematic diagram showing an example of an evaluation method of the charging characteristics of the photoconductor using each data of FIGS.

FIG. 17 is a diagram for explaining a method for measuring the amount of change over time of the surface potential of the photoconductor.

FIG. 18 is a diagram for explaining a method for measuring the photosensitivity of a photoconductor, in which (a) is the relationship between the light amount of an image exposure unit and the surface potential of the photoconductor, using the photoconductor property evaluation apparatus of the present invention. The figure which shows an example which measured, (b) is a schematic diagram which represented typically (a).

FIG. 19 is a diagram showing an example of an evaluation result obtained by evaluating the dependence of the photosensitive characteristic of the photosensitive member on the exposure wavelength of the image exposure unit, using the photosensitive member characteristic evaluation apparatus of the present invention.

FIG. 20 is a schematic view showing another embodiment of the photoconductor characteristic evaluation device of the present invention.

21A and 21B are diagrams for explaining a method for measuring optical memory characteristics of a photoconductor, FIG. 21A is a schematic diagram for explaining an example of a method for measuring optical memory characteristics of a photoconductor, and FIG. It is a schematic diagram for demonstrating the other example of the measuring method of the optical memory characteristic of a body.

FIG. 22 is a diagram showing an example of an evaluation result of evaluating the dependence of the charging characteristic of the photoconductor on the surface temperature of the photoconductor using the photoconductor characteristic evaluation apparatus of the present invention.

23A and 23B are views for explaining the configuration of the rotation detecting means used in the photoconductor characteristic evaluation device of the present invention, FIG. 23A is a schematic diagram showing an example of the configuration of the rotation detecting means, and FIG. It is a schematic diagram which shows the other structural example of a detection means.

FIG. 24 is a diagram showing an example of a measurement result obtained by measuring the circumferential distribution of the charging characteristics of the photoconductor using the photoconductor characteristic evaluation apparatus of the present invention.

FIG. 25 is a diagram showing an example of measurement results obtained by measuring the distribution of charging characteristics of a photosensitive member over the entire surface of the photosensitive member using the photosensitive member characteristic evaluation apparatus of the present invention.

[Explanation of symbols]

101 photoconductor 102 rotation means 103 charging means 104 pre-exposure means 105 image exposure means 106 surface potential measuring means 107 units 108 Defect detecting means 109 Transportation (for unit) 110 moving means (for defect detecting means) 201 substrate 202 LED 203 opening 204 rays 401 sensing electrode 402 support 403 lead wire 404 circuit elements 803 charging means 804 pre-exposure means 807 units 808 Defect detection means 811 Defect Detection Charging Means 812 Defect detection unit 2013 Surface potential measuring means 2014 Surface temperature measuring means 2015 Eccentricity measuring means 2301 rotating plate 2302 window 2303 photo sensor 2304 rotating rod

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Satoshi Furushima             3-30-2 Shimomaruko, Ota-ku, Tokyo             Non non corporation F term (reference) 2G066 AA01 AC16 BA60 CA14                 2H068 DA00 EA41                 2H134 QA02

Claims (30)

[Claims] 1. A rotating unit that rotates a cylindrical photosensitive member, a charging unit that charges the photosensitive member, an exposing unit that exposes the photosensitive member, and a surface potential measuring unit that measures the surface potential of the photosensitive member. And at least a defect detection unit that detects a defect on the surface of the photoconductor using a probe that generates an induced current according to a potential change on the surface of the photoconductor, the surface potential measurement unit and the defect detection unit, , A photoconductor characteristic evaluation device capable of performing operations simultaneously. 2. The photoconductor characteristic evaluation apparatus according to claim 1, wherein the surface potential measuring unit and the defect detecting unit simultaneously operate at different positions in the busbar direction of the photoconductor. 3. One or more units arranged at the outer peripheral portion of the photoconductor, to which at least the exposing unit and the surface potential measuring unit are attached, and a first unit for moving the unit in a generatrix direction of the photoconductor.
Moving means and second moving means for moving the defect detecting means in the generatrix direction of the photoconductor, and the first moving means and the second moving means are independently drivable. The photoconductor characteristic evaluation device according to claim 1, wherein the photoconductor characteristic evaluation device is present. 4. A plurality of units arranged at the outer peripheral portion of the photoconductor, to which at least the exposing unit and the surface potential measuring unit are attached, and a moving unit for moving the defect detecting unit in a generatrix direction of the photoconductor. 3. The photoconductor characteristic evaluation device according to claim 1, wherein the plurality of units are arranged so as to be fixed relative to a generatrix direction of the photoconductor. . 5. One or more units arranged on the outer peripheral portion of the photoconductor, to which at least the exposing unit and the surface potential measuring unit are attached, and a moving unit for moving the unit in the generatrix direction of the photoconductor. 3. The photoconductor characteristic evaluation device according to claim 1, wherein the defect detection unit is arranged over the entire area of the photoconductor in the generatrix direction. 6. The effective charging range is 2 cm or more and 15 cm or more arranged in the outer peripheral portion of the photoconductor and in the generatrix direction of the photoconductor.
one or more units to which at least the charging unit, the exposing unit, and the surface potential measuring unit, each having a height of 1 cm or less, are attached;
Moving means and second moving means for moving the defect detecting means in the generatrix direction of the photoconductor, and the first moving means and the second moving means are independently drivable. The photoconductor characteristic evaluation device according to claim 1, wherein the photoconductor characteristic evaluation device is present. 7. An effective charging range is 2 cm or more and 15 cm or more arranged in the outer peripheral portion of the photoconductor and in the generatrix direction of the photoconductor.
cm or less, the charging means, the exposure means and at least one unit to which the surface potential measuring means is attached, and a moving means for moving the defect detecting means in the generatrix direction of the photoconductor, The photoconductor characteristic evaluation device according to claim 1 or 2, wherein the plurality of units are arranged so as to be fixed relative to a generatrix direction of the photoconductor. 8. The unit according to claim 3, wherein a plurality of the surface potential means are attached to the unit.
5. The photoconductor characteristic evaluation device according to any one of 1. 9. The unit is provided with eccentricity amount measuring means for measuring an eccentricity amount when the photoconductor rotates and generating a warning signal when the measured eccentricity amount exceeds a predetermined value. 9. The photoconductor characteristic evaluation apparatus according to claim 3, wherein the photoconductor characteristic evaluation apparatus is provided. 10. The photoconductor characteristic evaluation apparatus according to claim 3, wherein the unit is provided with surface temperature measuring means for measuring the surface temperature of the photoconductor. . 11. The detection portion of the defect detecting means has a width in the rotation direction of the photoconductor smaller than the width of a portion of the surface of the photoconductor to be measured, in which the potential changes, of the defect, 11. The cross section in a plane perpendicular to the direction parallel to the rotation direction of the photoconductor has no edge, and the cross section has a shape having no edge.
Item. The photoreceptor characteristic evaluation device as described in the item. 12. The photoconductor characteristic evaluation device according to claim 11, wherein the cross-sectional shape of the detection portion of the defect detection means is a perfect circle. 13. The photoconductor characteristic evaluation device according to claim 11, wherein the cross-sectional shape of the detection portion of the defect detection means is elliptical. 14. A cross-sectional shape of a detection portion of the defect detection means is such that at least three arcs are connected by a radius.
The photoconductor characteristic evaluation device according to claim 11, wherein any one of the arcs has a shape facing the photoconductor surface. 15. The detection portion of the defect detecting means is made of a conductive wire having a wire diameter of φ1 or more and φ500 μm or less, and a length of the photoconductor in the generatrix direction of 0.2 to.
10 mm, which is parallel to the Z axis when the rotation direction of the photoreceptor is the X axis, the direction normal to the surface of the photoreceptor is the Y axis, and the direction perpendicular to the X axis and the Y axis is the Z axis. 15. Arrangement according to any one of claims 1 to 14, characterized in that
Item. The photoreceptor characteristic evaluation device as described in the item. 16. The material of the detection portion of the defect detection means is made of tungsten.
5. The photoconductor characteristic evaluation device according to any one of 5 above. 17. The photoconductor characteristic evaluation device according to claim 1, wherein the charging unit is a corotron charger. 18. A memory means for storing an output from the surface potential measuring means, wherein the rotating means generates a rotation signal when the photoreceptor is rotated, and the memory means receives the rotation signal. 18. The photoconductor characteristic evaluation device according to claim 1, wherein the photoconductor characteristic evaluation device operates in synchronization with rotation of the photoconductor. 19. The photoconductor characteristic evaluation device according to claim 18, wherein the rotation unit generates a pulse signal as the rotation signal every time the photoconductor rotates once. 20. Rotation detecting means for generating a rotation signal when the rotation of the photoconductor is detected, and memory means for storing an output from the surface potential measuring means, wherein the memory means includes the rotation signal. 18. The photoconductor characteristic evaluation device according to claim 1, wherein the photoconductor characteristic evaluation device operates in synchronization with rotation of the photoconductor. 21. The rotation detecting means is configured such that the photosensitive member is 1
21. The photoconductor characteristic evaluation device according to claim 20, wherein a pulse signal is generated as the rotation signal each time the photoconductor characteristic is rotated. 22. The photoconductor characteristic evaluation device according to claim 1, wherein the photoconductor has a photoconductive layer containing amorphous silicon as a main component. 23. A potential of the photoconductor using a means for rotating a cylindrical photoconductor, a means for charging the photoconductor, a means for exposing the photoconductor, and a means for measuring a surface potential of the photoconductor. Simultaneously performing a potential characteristic evaluation for evaluating characteristics and a defect detection relating to the presence or absence of a defect on the photoconductor surface by using a defect detection means including a probe that generates an induced current according to a potential change on the photoconductor surface. And a method for evaluating the characteristics of a photoconductor. 24. The photoconductor characteristic evaluation method according to claim 23, wherein the potential characteristic evaluation and the defect detection are simultaneously performed at different positions in the generatrix direction of the photoconductor. 25. The width of the detection portion of the defect detecting means in the rotation direction of the photoconductor is made smaller than the width of the potential changing portion of the defect portion of the photoconductor surface to be measured, 25. The photoconductor characteristic evaluation method according to claim 23 or 24, wherein a cross section of the detection portion in a plane perpendicular to the direction parallel to the rotation direction of the photoconductor has a shape having no edge. . 26. The photoconductor characteristic evaluation method according to claim 25, wherein a cross-sectional shape of the detection portion of the defect detection means is a perfect circle. 27. The photoconductor characteristic evaluation method according to claim 25, wherein a cross-sectional shape of the detection portion of the defect detection means is elliptical. 28. At least three circular arcs are connected by a radius in the cross-sectional shape of the detection portion of the defect detection means,
26. The photoconductor characteristic evaluation method according to claim 25, wherein any one of the arcs has a shape facing the photoconductor surface. 29. The detection part of the defect detecting means is composed of a conductive wire, and the rotation direction of the photoconductor is the X axis, the normal direction of the photoconductor surface is the Y axis, the X axis and the Y axis. 29. The photoconductor characteristic evaluation method according to claim 23, wherein the detection portion is arranged parallel to the Z axis when the vertical direction is the Z axis. 30. The material of the detection portion of the defect detection means is tungsten.
9. The photoreceptor characteristic evaluation method according to any one of 9 above.