JPS61500690A - electrophotographic copying device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Method for controlling charge on a photoconductor and field of invention This invention controls the level of electrostatic charge on the light 4 surface on which the electrophotographic image is to be made. An improved method and apparatus for use with known electrophotographic reproduction equipment such as copiers When the area of the photoconductor is moved through the charging location, the area of the photoconductor is An electrostatic charge is placed on top. The photoconductor is then moved to the exposure location where the area is exposed. The area is exposed to imaging radiation to form an electrostatic latent image of the document to be reproduced. child The latent image is then developed and, in the case of plain paper copiers, subsequently transferred to the paper. Then, the subject will appear on this paper. The photoconductor is then cleaned. Then, preparations for the next copying process are made.

In such devices, a nearly uniform charge is applied over the area where the latent image is to be formed. It is important to give If the charge in some part of this area is too small, the complex A thin washed-out area may appear on the photo, and this area may If there is too much charge in one area, some areas of the copy will be too dark compared to other areas. Sometimes. Therefore, the copy quality for material with pictorial markings on the photoconductor is This can be seriously affected if non-uniform charges are applied.

In the prior art, US Pat. As exemplified by The equipment is described.

In this device, a voltage is applied to the corona wire and the light 24'tI! L-sex belt Positive static charge on top? I am trying to grant it. The level of charge applied to the belt is , is measured by an electrometer placed close to the belt, and from this electrometer The signal is compared to a reference signal representing the maximum level intended for loading the belt.

If there is a charge deficiency, the charge level should be increased to the extent necessary to bring it up to the standard charge. increased to. The signal obtained from the electrometer indicates that the charge exceeds this maximum level 2. In electrophotography, if the photoconductor used Select a positive or negative electrostatic charge based on the type and charge the photoconductor with this electrostatic charge. is known. This charge is applied in the direction of movement of the photoconductor past the charging station. ? By a corona load iii+t consisting of one or more corona wires traversing It is desirable to be placed.

Using a positive corona charge1, in this case, the photoconductor can be placed on the photoconductor using known charging techniques2. It is expected that uniform charge can be applied. For negative corona charge Control is more difficult and significant charge non-phoresis can occur. positive charge A glow appears from the corona wire and surrounds the entire length of the corona wire. A uniform glow is observed, indicating uniform current flow from the corona wire to the photoconductor. There's something I'm doing. On the other hand, there are a few random points; - At the end, there are often negatively charged particles. Occurs when the Rona wire is overflowing. This glow spot is caused by non-uniformity in the charging of the photoconductor. is related to the occurrence of The one glow is caused by the changing voltage of the humidity inside the copying machine or something like that. Oil may appear on the corona wire at various locations during the day due to other factors. Therefore, the charge non-uniformity changes with time (R.M. Sha7 Art). , "Electrophotography" 1975 edition, pages 466-472 (R, M, 5chaff ert.

Electrophotography, 1975 edition, page s 466-472)w). Small amounts of non-uniformity are not tolerated, but before As shown, variations with large non-uniformity can have a serious impact on image quality2. Ru. The extent of this problem depends on the nature of the equipment and the material to be copied. joy However, manuscripts with continuous tones or no-tones pose more problems than copying the main text. raise Color copiers require more uniformity in charging than monochrome copiers. shall be.

It is an object of the invention to If a large change occurs, the direction of movement of the surface passing through the charge source will change in the direction of movement. A load is generally uniformly loaded when there is a tendency for charges to adhere to the surface. To provide an imaging area 2 of the electrified photoconductor. As used here, “ The term "generally uniform charge" refers to the fact that variations in charge level can occur from area to area. However, the various parts that make up the area fall within a desired narrow range of values. Has level 7 of charge.

Another object of the invention is to provide a charged battery having a charge level 2 different from a desired reference level. The imaging exposure of the four giant bodies of light caused by this imaging exposure causes a change in charge from the reference level. The trick is to get used to begging.

The main feature of this invention is the load i! an electrostatic image that is electrostatically charged and developable by a device Improved electrophotographic method for controlling charge on a movable photoconductive member formed by This is achieved by a copying method and apparatus. The present invention provides a method for recording charge levels on a photoconductive member. Measurements are taken by placing the bell at each of a plurality of positions in the direction of movement of this member. and a device responsive to the signal. The charge level at one lateral position that has a different charge level than the reference level. It is the same as an adjustment device that can differentially adjust the signal.

The invention further provides a method for producing a photoconductive member by means of a narrow beam of radiation powder modulated with imaging information. The photoconductor is exposed to light to form a static image, during which data about the charge distribution on the photoconductor is collected. Converting one or more signals to the electrostatic imaging area during exposure of the narrow beam 2 It modulates the charge level on the photovoltaic material, which was different from the base level, to compensate for it. The sea urchin method and apparatus are the same.

Brief description of the drawing For a detailed description of selected embodiments of the invention described below, reference is made to the accompanying drawings. This is done in these drawings.

FIG. 1 is a schematic side elevational view of an fs copying system equipped with an apparatus according to the invention; Figure 2 is similar to the generally uniform charge deposition on the photoconductor shown in Figure 1. FIG. 5 is a schematic diagram of parts of the copying machine shown in FIG. 1 is a flowchart illustrating the sequence of operations used by a controller to Figures 4a to 4c and e show hypothetical examples of charge level readings for optical four-electrode depletion. FIG. and FIG. 4d is a diagram representing the illumination of a hypothetical example according to a lamp, FIG. 5 is a schematic diagram showing an arrangement of lamp groups that may be used in accordance with the present invention.

FIG. 6 is a diagram 10 similar to that of FIG. 2 showing another embodiment of the invention; Figure 7 shows part Y of the copying machine shown in Figure 6: used by the control device for sub-control. FIG. 8 is a flowchart illustrating the sequence of operations used, and FIG. 1 is a schematic side elevation view of an example; FIG. 9 provides additional details of the elements forming the charge control device for the embodiment of FIG. It is a schematic diagram showing a black term.

Explanation of adoption implementation schedule Since devices of the type described here are well known, future explanations will focus particularly on this development. This invention is directed to elements forming part of the invention or cooperating more directly with this invention. .

A general understanding of the web electrophotographic reproduction apparatus 10 for which this invention is useful includes: Let us now discuss Figure 1. As shown, one photovoltaic web 16 is shown. The optical 4-electric member is movably adjusted around the rows 24 to 9 in the direction shown by arrow A. It is arranged. For the sake of simplicity, roller 4 is assumed to consist of a motor/grip configuration. ℃ is driven by the fs drive mechanism 18 as shown. Insulating layer or surface 16a of web 16 is charged at a corona charging station (charger) 20. The charger 20 is one one or more corona-generating wires 20a, a shield 20b, and a photoconductor section from the wires; It consists of a gamma grid 2DC that regulates the flow of negative corona current to the material.

Thereafter, at a suitable time, the information medium 15, such as a document, is transferred to the image (tld light station). is illuminated by the radiating edge from the Franche lamp 14. This radial edge is about love. It is reflected by the news medium and the load 1 of the web 16 is delivered by the V lenses 15! Projected onto the insulating surface 16a Is there a charge? Selective dissipation to form an image of the medium 15 in specific areas of the web. do. For a more detailed disclosure of Webb, published October 26, 1971, See commonly assigned U.S. Pat. Nos. 5,615,406 and 5,615,414. I want to be. As will be explained in detail later, there is a connection between the exposure station and the charger 20. A plurality of light sources 56 and an electrometer are arranged.

Folds! ! In 10, the moving electrostatic image is further divided into fine parts and one part comes into contact with the toner particles. The toner particles are applied to the charged web surface in the texture defined by the electrostatic image. A developer station 22 deposits and forms a visible toner image on the copy sheet. a transfer station that is transferred to a receiving surface of 26 and subsequently permanently fused to this surface; 25, and a cleaning station 5 in which residual toner particles are removed from the web 16. There is 1.

At the development station, the electrostatic image on the insulating surface 16a of the web 16 is transferred to the development station. Two magnetic brushes or rollers 24a and 22 are mounted within the housing 27. and 24bY are allowed to pass. The housing 27 contains a mixture of toner and carrier particles. A container of developer supplies? keeping. Brushes 24a and 24b are conventional It may be constructed according to any one of various designs known in the art. similar For a more complete description of the general construction of reproduction equipment, please refer to the commonly assigned See US Pat. No. 4,025,186.

Although a web-type copier is shown, the present invention uses a drum and a thin film photoconductor. It will be appreciated that it is also particularly suitable for use with reproduction apparatus. Izu In either case, as one skilled in the art would understand, the built-in program Copying by effectively using a microcomputer equipped with a system as a logic and control device The heating operation can be controlled.

Next figure 2? When viewed, a schematic representation of a device constructed in accordance with the present invention is shown. It is shown. The electrometer or electrostatic voltmeter 50 is a common one, and includes a power supply, an amplifier, etc. and an output circuit section, and a globe 50b mounted on the rotatable leadscrew 52. The module 50aY includes a module 50aY. The step motor 54 is supplied with energy. When the lead screw is rotated 52'Y, the lead screw is moved across the width of the web 16 in the direction of arrow X. Translate probe 50b'a' in the transverse direction shown. Charger 20 and electrometer pro A plurality of light sources 56 are arranged between the tube 50b and the I! has been done. These light sources are Each emits light with an appropriate spectral frequency, and the photoconductor responds to this to form a photoquadruple. The exposed portion of the exposed portion is made partially conductive so that the charge level on this exposed portion is at least partially Partially reduced. These light sources consist of multiple illuminance lamps, which each transmitting light into a respective light tube that transmits light in a respective orientation 1 on the web 16. good. Other light sources that can be used include plasma displays, LED Array, digitally controlled 1V chrominescent plate, PLZTi crystal hole provision Equipped with a laser or), a logen rung or a neon rung, and a hole in the PLZT crystal. There is a long arc lamp. The selected embodiment will be described with respect to a panel display.

An example of such a panel display is Burroughs' self-scanning panel display. , Model SSD 0124-0059 (BurroughsSELF-8CA N Panel Display, Model 5SDO12d-0059) However, this will be explained in more detail below.

The apparatus shown in FIG. 2 is described for the hypothetical example shown in FIGS. 4a-c. be done. In Figure 4a, the nominal or The desired charge level VO is shown at the rectum. In this example, the customary direction rXJ is The actual vO in the ileum is denoted by There is some variation around this nominal level due to the non-uniformity of v A certain amount of change from O, for example ±10 volt change 1, Makonoshi 1] is acceptable. is possible, and this range of variation is therefore designated as a modest band. begging for things First of all, let's discuss the charge level in terms of absolute value or magnitude. Therefore, a charge level of -550 volts is equivalent to a charge level of -540 volts in this case. The higher and lower levels are the same for nominal ■0.

It will be noted that some parts of the photoquadruple have charge novels outside this band. ? have. In accordance with the present invention, charger 20 and light source 56 charge the photoconductor 16. The load level 7 is adjusted to bring it within the adopted uniformity band. . Figure 4 e Beggar.

Copy warm once or twice a day or more often if necessary before being placed in copy mode. , the actual charge level■. The calibration operation is performed to ensure that - is within the spherical band. It is done. During this calibration, the charger 20 and the light source 56 are Adjustments are made. After calibration, the copying machine is operated in copy mode to avoid overproduction of copies. You can do the process. Proofreading? To start, the operator must press switch 45Y. , an i-insertion signal is given to the microcomputer 47, but this microcomputer 47 It can be seen that the computer also controls the operation sound of the copying machine 10. Press switch 45 Before starting, the signal V1 is applied to the addition port 48 during the start of the pumping machine operation. As a result, the low voltage control grid power supply device 49 is set to properly adjust the charger 20. The charger has a nominal charge level of 1,550 volts. 2 to occur become. The actual ■ placed on the photoconductor as shown in Figure 4a. is this public This is different from the nominal level. Grid-controlled programmable power supplies are well known in the art. For example, as disclosed in U.S. Pat. No. 4,166,690 and U.S. Pat. No. 4,294,556, It is shown.

Calibration mode (in which the microcomputer 47 issues commands in the form of a series of pulses) to the motor 54. The motor 54 is actuated by the electrometer probe 50bxu. Move in the transverse direction of the web 16. For a particular example, as shown in Figure 4 blc. For example, there are eight transverse positions for an image area approximately 55 cm wide. Each position (Mo (determined by the number of pulses sent to the microprocessor) is the analog-to-digital converter 57Y: This converter is operated by the microcomputer. Determining the charge level at a particular traversal position as a manual input to the equipment associated with the computer. provides a digital representation of a predetermined one of eight locations in the storage device. is memorized. The electrometer has enough power for the photoconductor to make one complete revolution through the electrometer. It is desirable to remain in each position for a reasonable amount of time. This allows the electrometer to detect that characteristic of the photoconductor. The average reading for a certain narrow strip section can be given. First specific transverse position After the position charge level is detected and stored in storage, each of the following seven positions Measurements are taken about. Figure 4 shows the signal level 7 in digital format. ing. After the positions of all eight units have been measured and stored, the microcomputer 4 7 can take these digitally formatted readings by direct measurement of Vo or by . The public detected by the use of the low grid supply voltage V1 waiting for the known relationship 7 with Compare with the nominal level vo. This is done by an analog-to-digital converter 62. Converts the analog voltage V1 into a digital format that is stored in the computer's storage device. This can be done by The value of nominal v0 is then calculated or other This value is derived from the electrometer for the charge level at each traversal position. The measured values are compared with each of the eight measured values according to the method. Charge at any inertial position 11tlC If the level is measured below the lower limit of the monospheric band, the computer Uniform this charge level by increasing the charge level at a transverse position that has a charge level. Determine the minimum additional charge required to reach the lowest value for the sexual band. necessary and A signal V representing the additional charge applied.

is then provided by digital-to-analog converter 64, which converter responds to and provides an offset signal to the summing boat 48 to supply the grid of the corona charger 20. Adjust the supplied voltage. Conveniently, the computer is shown in Figure 4C. The charger is adjusted as shown so that the lowest measured charge level nt is within the lower limit of the uniformity band. Cross one or more additional electrometer probes 50b until they just enter the can be programmed to do so. Due to the final intersection, the charger becomes 1@hardness appropriately. After determining that the charge level at any transverse location is has data regarding whether or not exceeds the upper limit of the uniformity band. either If the charge level at the position is measured to be greater than the upper limit of the uniformity band, then The computer calculates the charge level at each position higher than, for example, the midpoint of the band or the nominal v0. a signal proportional to this difference is provided to the lamp controller 70. . The ramp controller is a specific number that is related to a specific traversal position located on the The lamp t also represents a control module configured in the same way. Figure 5 shows An example of a possible arrangement of lamp groups is shown, which corresponds to the transfer of the photoconductor indicated by arrow A. If the moving direction is offset as shown and brought together, the working area will emit light 4. Consists of five nonel display devices installed to span the width of the body 16 . Each of these displays has 17 lines? Each row has 192 gas plasmas. There is a machine display rung 56a. Of the 17 rows of indicator lamps in each column, that column a lamp that is illuminated to erase the charge from each transverse location on the photoconductor where there is is selected. For example, by illuminating one or more lamps in the first row and first column, the photoconductor It is sufficient to remove a small amount of overcharge Z (beyond the nominal vo) from the first traverse position above. child If there are more supercharges (beyond the nominal V) at the positions of The charge t is also reduced to V0 by illuminating each of the lamps in one to 17 rows. Just make it a little less. Each of the transverse locations on the photoconductor where the charge level measurements are made Since it has each group of lamps associated with a given column, one or more of these lamps Illuminate every 7th row and calculate the charge at the photoconductor position relative to each row of lamps. All you have to do is decrease it. The light from the lamps tends to spread out, so the ends of each row Avoid illuminating lamps in close proximity to one column so that the light from the lamps is in an adjacent position. It is advisable to avoid the influence of 7 and 7 of 7. Therefore, the line near the center of the column By using only the light source and using the tendency of the light to spread out, the width of each position can be overridden. It is desirable to do so. The level of illumination emitted by each lamp is It is desirable to be preconfigured to give fine control over the charge reduction effect of the pump. Delicious. Therefore, before the U/P, the filter Y:rIL and/or the voltage to the U/G should be applied. The flow can be adjusted so that each lamp dissipates only a small amount of charge.

Returning now to the fS example shown in FIG. 4, the lamp ff1l controller 70 is signal (C) required to reduce the charge at each location to a nominal V0. Light up as many lamps as required in each column and row. Therefore, each overcharged i The charge at is equal to the charge level measured at that location and in this case the nominal value V .

It decreases differentially according to the difference from the reference value. This reference value is also above the uniformity band. However, there may be a limit.

Nominal level V, as shown in FIG. 4d. at a transverse position on the photoconductor higher than Only the corresponding lamp is illuminated and the charge at the corresponding transverse photoconductor location is Nominal V. Only a selected number of rows are illuminated to reduce the level. correspondence After the lamp is illuminated, a public Name V. Nominal v0 to ensure that charge levels larger than is compared again. If either position had a still larger charge level The computer then adjusts the lighting for each traversal location based on this new measurement. Allows the lamp controller to determine the number of lamp lines to be displayed. Figure 4e Adjust the charger so that the lowest measured charge level is within the lower limit of the unispheric band, as shown in Light the appropriate erase lamp so that everything on the photoconductor The transverse position of falls within the uniformity band. Since the charging equipment has been revised, this will require a suitable charger. Load erase lamp? be used in copy mode with illumination and charger properly adjusted; Can be done. As noted from Figure 3, after reading the electrometer, the charger or The process of adjusting the amount of charge used is an iterative process. That is, by making measurements The cyclical process of adjusting the charger or lamp is carried out until the desired result is achieved. Iterate based on value.

If desired, please adjust the charger first so that this is the photoconductor? overload and therefore uniform It is never likely to have any transverse position lower than the minimum of the sexual band You can do it like this. In such cases, a controller to give the offset is necessary. (and only a controller matched to erase the charge would be useful.

Although one movable electrometer is shown in the discussion of the adopted embodiment, multiple fixed electrometers are shown. Electrometers are provided and placed across the width of the photoacid conductor, and those of the electrometers are Appropriate circuitry may be provided to take each reading in accordance with the chronological order. It will be noticed.

Reference will now be made to a second embodiment of the invention shown in FIGS. 6 and 7. child In the embodiment, the same elements as described with respect to the first embodiment of the invention are identified by the same code. These same elements are machined in the same way as previously described. Therefore, the discussion regarding this embodiment will be based on the operation of this embodiment and the operation of the first embodiment. All you have to do is equalize the difference. In the second major embodiment, the charge erasing line of the embodiment shown in Figure 1 is used. A needle charging station 55 is used in place of the pump. Charging station 5 5, a plurality of stiff needle-like charging elements A-H are arranged in the direction of movement At of the photoconductor 16. arranged horizontally. During the calibration stage of the device, the -order charger 20 and the needle charger A- H are turned on together and these charged elements emit a corona current. In this example In this case, both charging stations emit a negative corona current onto the photoconductor. electric In this case, the positioning globe 5Cla is moved in the '1:X direction across the photoconductor to emit light. The charge level at each of eight locations across the width of the conductor is measured. electrometer mo Joule 50b then supplies these analog signals to an A-D converter 57, This converter then converts the digitized values of these signals into a microcomputer. 47. Besides storing these values, the microcomputer also The grid power supply reference voltage vlt is stored in the storage device, and the limit value of the desired uniformity band is is being calculated. Now, with regard to Figure 7 and the discussion that immediately follows, the use indicated in parentheses. The words are intended to describe alternatives. This alternative example is This is explained by using the word t in parentheses instead of the word immediately before it. Chobe all positions have a charge level lower (higher) than the lower (upper) level of the uniformity band. If the reading on the electrometer 50 indicates -charge 1! location 20 The charge output is applied to the summing port 48 by combining it with the signal V1. Child voltage V. It can be increased (#small) by increasing (decreasing) . electrometer Again take measurements at each of the 8 positions and make sure that the position at the end is in the uniformity band. Lower (higher) than the lower (upper) level! Determine whether you have a loading bell or not. Ru. This process is repeated iteratively until this condition is met. This condition is met. Once the cross-section position of the cross section is adjusted to the desired uniformity band, the microcombinator then How much additional charge is needed to make the charge level that falls within the acicular charge Decide what is needed from the vessel. Each of the charged needles is charged with an electrometer. Differentially adjusted for lateral reading. Continuous additional readings by electrometer If the voltage at the rear needle charger 55 is adjusted repeatedly, the parts under the needle charger 55 will be The charge level on the IC is brought to a level within the desired uniformity band. My A needle-like charger controller 56 connected to the computer controls each charge needle A to H. The determined voltage setting value is memorized and this setting value is maintained during the copying mode of the copier. maintain. This implementation consists of 8 charged needles, one for each of the measured cutting positions. However, even more needles can be placed across the width of the photoconductor. Putting this all together, for example, if four needles are at the same electrical potential, then this? use It is understood that the charge at each of the eight transverse positions may be adjusted by will be done. This means that the effect of the 6 needles adds charge along a narrow band below this needle. For example, four of these bands are at the transverse position t95y. , 'r are equal to the width of each band, which may be desirable.

The effect of the charge conditioning device, parts 56 and 55, as described in the first and second embodiments. As a result, the non-uniform charging by the corona charging station 20 is adjusted differentially to provide light guidance. The aim is to provide a generally uniform composite charge over the body. That is, the above In embodiment 2, by selectively enabling the charge twinning device or the charge increasing device. A generally uniform electrostatic charge was formed over the area where the electrophotographic image was to be formed. This issue The present invention further relates to the charge reduction device and image exposure device described herein in connection with electrophotography. Since the optical devices are both involved in the use of light, there is no possibility that the charge will decrease during the exposure operation. It is contemplated that the use of less equipment will be considered. If you keep it, the exposure to light will decrease. If this is done by using a different beam, the intensity of the beam or any “point” According to the information obtained from the vt electrometer and the image information source, All you have to do is adjust it.

In this regard, reference is now made to Figures 8 and 9, in which A scanning exposure type electrophotographic apparatus is shown. In these drawings the prime ( -) are similar numbers shown in Figures 1 and 2 with similar functions. Corresponds to the part. In this example, the illustratively shown mounted on the drum The photoconductor 16' includes a negative corona current discharge suitably spaced from the photoconductor. It rotates past a charging station 20' consisting of a device and a grid and is thereby charged. Ru. The exposure station, which will be described in more detail below, includes a rotating multifaceted surface 81 There is an exposure beam 80 reflected from. The beam modulated with the appropriate true image is connected to the drum. They synchronously traverse the width of the photoconductor and form a silent violet image on the photoconductor. light 4 electric body then passes through the current development station 84, which station: i is shown. It may be of the type shown in FIG. this At the station, the photoquadruple body is not sufficiently discharged by the exposure beam. Toner particles adhere to the area and a latent image is developed.

The developed image is then transferred to a web of copy paper that is fed into contact with the photoconductor. . The copy paper receives an electric charge from an electrostatic discharger 86 to cause development from the photoconductor to the copy paper. Image transfer occurs. Copy paper is supplied from a supply reel 88 and guided by a guide roller 90. 0 and is advanced to a receiving box 94 by a drive roller 90. #! 1st place device 95 causes the image to be deposited on the copy paper ζ (electrical layer) when the copy paper is sent to the box 94.

The information content of the scanning point is modulated or fluctuating in the light with respect to its position within the scanning width. Since it is expressed in intensity, it provides a usable image. The constant strain point is the photoconductor's A charged surface dissipates its static charge according to the intensity of light on it when it crosses at a given fixed angle. let

The electrostatic charge pattern thus generated is developed and then copied as described above. Transferred to paper. After the photoconductor is then cleaned by a cleaning device 98, , is recharged by the charging device 20' in preparation for the next copying process. The polygon mirror 81 is ℃ continuously driven by the printer 100 and used to obtain the image signal of the original. The rotation is synchronized with the synchronization signal that represents the strain rate, and this signal is shown in Fig. 9 as " A binary storage device 95 labeled “Page Storage Device” You can memorize it using formulas.

The beam is also labeled ``Charge Uniformity vs. Beam Intensity Correction'' and stored in memory 91. It is stored in base format and modulated by a signal representing charge control information. This feeling The information travels across the width of the photoconductor and at a particular transverse location of the photoconductor. The probe is charged by a charger 20' and gives a reading of the voltage level of the light guide. It is obtained by an electrometer 50' equipped with a probe 50b'v. Shown in Figures 1 and 2. The microcomputer 47' program is implemented as shown in FIG. These readings are taken with an electrometer during the preparatory period of the copying machine or when the copying machine is running. Or, it would normally be created at certain times during the day when you are not in copy mode. UiCj is good. The reading of probe 50b' is taken by electrometer module 503'. is detected and the analog signal is converted into a digital signal by converter 57'. Ru. The microcomputer 47' then performs the implementation 911 of FIGS. 1 and 2. There are locations that have a charge level below the lower limit of the uniformity band as discussed earlier. I will decide whether or not to do so. If additional charges are required, repeat with an electrometer. The measurements show that the transverse position of the entire plate is small (and charged to the lower limit of the uniformity band). Grid voltage source 49' is adjusted until this is determined. Used to calibrate the charger. The final set of measurements is then used by the computer to eliminate the excess charge. Due to the existence of Adjustments to the intensity of the light beam are calculated.

These adjustment values are stored in storage device 91 in digital format.

As can be noticed in FIG. 9, the optical information from the page store 1i95 The signal representing the charge adjustment value is combined in multiplier 96 with a signal representing the charge adjustment value.

The resulting signal is then converted into an analog signal by a digital-to-analog converter 97. and this analog signal is coupled to an acousto-optic modulator 99. , focused onto this modulator by beam forming optics 105 and filter 102 The photoconductor 1 is reflected by the polygon mirror 81 through the Z passage port and passes through the optical system 107 on the field plate 1. Reach 6' above. The optical sensor 108 is placed near one edge of the optical quadrupole. At the start of each page row, the light reflected by the polygon mirror 81 is also detected. Is this the sensor? These signals and the signal from the shaft encoder 105 that detects the rotational position of the drum are sent to the microphone. is supplied to the computer 47' for synchronization with the moving scanning exposure of the drum. Be used.

In the one-scale embodiment just described, the laser beam is guided along a line with six strokes. A large number of discrete points (modulated at ζ) across the width of the electric body. In this regard, modulation requires an input consisting of optical information and charge control information. . If necessary, change the charge control information to adjust the Other factors may also be corrected. When copying blank areas of original documents, please be sure to One beam is defined here as the total exposure intensity, and it is equal to the intensity of one to five, so , the charge level of the corresponding area of the photoconductor decreases, below which the charge level of the corresponding area of the photoconductor decreases. The area of the photoconductor corresponding to the According to the signals from the "Page Store" device and the "Charge Uniformity vs. Beam Intensity Correction" device. The charge in this area forms an electrostatic latent image, and this image: the developing step. When passing station 84 ((developed), RT load - palpitation versus beam intensity correction ” Is the signal from the device to a specific location? is detected by the electrometer 50' and one electric charge is detected by the electrometer 50'. A predetermined "-ball" whose level and value are stored in the micro combinator's memory. It is related to the difference between the desired charge and the seven bells, as exemplified by the "sexual band".

In general, exposure of a light guide with a laser beam is performed using a constant strain of the light guide. This is done in such a way as to give a co/truss l-Y in the prenatal print. Print The bright area at is the bright area of many (or all) points in the corresponding area of the photoconductor. Created by giving a full exposure, the gray areas correspond to the corresponding areas of the photoquadrupole. By giving a full exposure of only a few points in the Providing the appropriate amount of exposure to each point in proportion to the degree of a desired in the print. and (C), and the black areas correspond to the corresponding areas of the photoconductor. It is created by exposing a point to light. Photoconduction due to constant strain of laser beam Complete exposure of any point on the body means that the charge level at that point, t, below which toner will not stick. It is possible that the initial It usually does not matter whether the charge is higher or lower than the nominal vo. The important thing is that the image light Points in the image area that receive no or very little V. charged to This is to ensure proper development.

It is also important to address the gray areas of the print and the desired density for this area. Therefore, the voltage of a point in the image area that should be charged to a voltage level lower than vo The charge level is changed according to the density, image correction information, and charge correction information. child Keeping in mind that the information stored in page storage requires complete exposure. A signal transformer 96 and AOM 99 in which a multiplier represents this information at each point The multiplier may be configured so as to provide the charge control information and suppress the charge control information. page memory At each point where exposure is required by the device, the multiplier provides a charge correction information signal. V-zapem's change IJ' to a level lower than its full exposure level, +4 electric Adjust the charge level at such points above to a level within the monospherical region. Perfect In respect to the extent that less exposure is required by anti-exposure or page storage. In this case, the 1 multiplier combines the information signal of the page storage device and the information signal of the charge correction device. The laser beam must be modulated at such a point to an appropriate level for the desired concentration. Le Shinsuru.

What has been explained so far regarding the implementation of FIGS. 8 and 9 regarding laser beams? I've been doing it, but , a narrow beam of light modulated by a single piece of image information that exposes the image area on the photoconductor. It will be appreciated that other devices for forming a system are known. . Like a light emitting diode (LED) array that extends across the width of the photoconductor. These devices modulate various LEDs with image information and charge control information to generate image-forming exposure. Fluctuations in charge level from a reference level during light operation can be corrected.

Many of the sources of charge non-uniformity are time dependent. the characteristics of the illumination provided may not be adequate for the desired uniformity at the end of the day. That can certainly happen.

Many control algorithms are required to automatically enter proofreading mode from copying mode. You can use algorithm. For example, what Fukushakuma can tolerate is Depending on the size of the maternity, the operator does not need to start the calibration mode. You can choose to enter calibration mode once a day, twice a day, and so on. example For example, automatically during the preparation period of the Enoki copier or between the start of the job and the first copy. Please enter the calibration mode in 11q.

Engraving (no changes to the content) LI diagram 9th concave Procedural amendment (formality) 6. Person who makes corrections Relationship to the incident: Applicant Name (7 [17) Eastman Kodak Company 5, date of amended order November 19, 1985 (shipment date) M! 1 Loss of atmosphere

Claims (1)

[Claims] 1. A movable member, particularly an electrostatic image that is electrostatically charged and developable by a charging device. a photoconductive member formed, an apparatus for measuring the charge level on the member, and The electrophotographic copying machine is equipped with a device for adjusting this level to a reference level. A first device (47, 52, 54) is provided, which measures the measuring device (50). control the measuring device (50) in a direction transverse to the direction of movement of the member (16). The charge level at each of a plurality of locations is measured and the charge level is generating a signal indicative of a bell, and in response to said signal and said a second device (47, 70) in operative relationship with the regulating device (56, 35, 39) of the second device (47, 70); , 47, 36, 47', 91, 96, 97), which differs from the reference level. It is possible to differentially adjust the charge level at a transverse position with a charge level of The electrophotographic copying apparatus described above. 2. Said conditioning device and a second device are arranged to generate a narrow beam (80) of radiation. equipment (99, 101, 102, 105, 106) and this beam (80) It is equipped with a device (97, 99) for modulating the point at each position. a signal representing the image to be formed on the member (16') at and for said position; can be exposed with a signal representing the difference between the charge level measured by the sensor and the reference level. 2. The copying apparatus according to claim 1, wherein the copying apparatus has the following features: 3. A light source device (wherein the adjustment device is arranged transversely to the direction of movement of the member (16) 56), and the level falls within the range between the minimum and maximum level of the standard. of the reduction at the location where it is necessary to differentially reduce the charge level up to the exposing said member (16) to non-imaging light in the amount required for 2. A copying apparatus according to claim 1, wherein the copying apparatus is capable of: 4. Said adjustment device comprises a plurality of needle-like elements arranged transversely to the direction of movement of the member (16). A charging device (35) is provided at the location where it is necessary to apply a charge differentially. and applying an additional corona charging current to said member (16) in the required amount. Ensure that the lever position is within the range between the minimum and maximum reference level. 2. A copying apparatus according to claim 1, wherein the copying apparatus is capable of: 5. A third device (47, 48, 49, 64) is provided, which controls the reference minimum level. in response to a signal generated by the measuring device (50) representing a charge level lower than the In response, the charging device (20) is adjusted to increase the charge level on the member (16), ensure that all parts of the member have a charge level greater than the reference minimum level. A copy according to claims 1 to 4, characterized in that it can be Device. 6. The first device (47, 52, 54) sends the measuring device (50) after each charge adjustment. Measure the charge level again at each of the multiple locations and then If the charge level exceeds the respective reference level as a result of measurement, the second device (47, 70, 47, 36)) or the third device (47, 48, 49, 64) on the member (16) again to the adjusting device (56, 35) or the charging device (20), respectively. Adjust the charge level so that all parts of this part have a charge level within the reference level. and at the same time, the charge level at each position is within the reference level. the first, second and third devices are each operated repeatedly until the A copying apparatus according to claim 5, characterized in that: 7. Imposing an electrostatic charge on an area of the surface, especially the photoconductive surface, increases the charge level on this surface. a method that renders the image suitable for forming an electrostatic latent image by exposure to image-bearing radiation. a method of moving said surface in a first direction past a charging location and depositing said surface on said surface; The charge level on this surface is determined by applying a charge and measuring the level of charge on this surface. In the method carried out by adjusting the bell to a reference level, the measurement a plurality of positions traversing said surface (16) in a second direction transverse to the direction; What is done about the charge level in each and how it differs from the reference level? The charge level is adjusted differentially at each location that has a different charge level. The above method, characterized in that: 8. Charge conditioning uses light to differentially reduce the charge on said surface (16') and that said surface (16') is in the same position at the same time. image information to form a latent image and the charge level for a specific position. The charge at the same position is differentially decreased according to the difference between the measured value and the reference level. and charge reduction information for the purpose of The method according to claim 7. 9. A narrow beam of light, especially radiation from a laser, is used for charge adjustment, Claim characterized in that this is scanned across said plane (16') The method according to paragraph 7 or 8. 10. Claim characterized in that an LED array is used for charge regulation. The method according to item 7 or 8. 11. an electrostatically charged member on which a developable electrostatic image can be formed in the image area; a device for measuring the charge level and converting this charge level to the development of unexposed points in the image area; electronic with a regulating device to give a signal to adjust to a reference level suitable for 1. A photocopying device for forming a narrow beam (80) of radiation. 01, 102, 105, 106), and the member (16') by this beam (80). ) is provided with a device (81) for exposing a point on the beam; (80) is an image information signal representing the image to be formed on the member (16'); While exposing (16'), the image information is modulated by the modulator (97, 99). Exposure of a certain point is performed according to the information signal, and the modulation device (97, 99) At points on the image area of the member (16') that do not require exposure due to the information signal, Beam (8) with a signal to adjust the charge level on member (16') to a reference level. 0). 12. A corona charging device (20) charges the image area of the member (16) with at least a negative electrostatic charge. is characterized by being charged to a level suitable for forming a developable electrostatic latent image. , Claims 1 to 4, 6, or 11. 13. Imposing an electrostatic charge on the latent image area of a surface, particularly on a photoconductive surface, increases the charge on this surface. the loading level is suitable for forming an electrostatic latent image by exposure to image-bearing radiation. the surface by moving said surface in a first direction past a charging location; Add a charge to the surface and measure the level of charge on this surface to determine this level. generating at least one signal for adjusting to a reference level suitable for developing the latent image; In the method carried out by The photoconductor is exposed to a narrow beam of radiation that exposes the area and forms an electrostatic latent image. on the surface according to the initial image information and the difference between the detected charge level and the reference level. at least one charge adjustment signal for differentially adjusting the charge at transverse positions of the said method, characterized in that the latent image area is modulated while exposing the latent image area by .