JPH0843951A - Reader/printer - Google Patents

Abstract

PURPOSE:To accurately carry out the correction of unevenness in the quantity of light. CONSTITUTION:A light-receiving element group 15 reads the transmitted light of a microfilm 1 (not shown) during prescanning, and sends it to a multiplexer 16. A CPU 18 changes over the control signal of the multiplexer 16, and successively and repeatedly sends out the output of the light-receiving element group 15. The output of the light-receiving element group sent out from the multiplexer 16 is amplified by an amplifier 17, and then is sent out to the CPU 18. The density data read by the light-receiving element group 15 during prescanning are subjected to the deletion, averaging, and arithmetic processing by the CPU 18 for obtaining the degree factor X, and on the basis of the obtained degree factor, an optimum correction table for correcting unevenness can be selected. During main scanning, the light quantity control of a lamp 2 is carried out by a lamp regulator 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reader printer having a function of projecting image information on an information recording medium such as a microfilm on a screen and a function of guiding image light to a photosensitive drum or the like and recording the image light.

[0002]

2. Description of the Related Art Conventionally, a function of projecting image information on an information recording medium such as a microfilm on a screen,
There is known a reader printer having a function of guiding image light to a photosensitive drum or the like to record the image light.

FIG. 14 shows the structure of a reader printer. In the reader printer 100, the light of the lamp 102 reflected by the reflecting mirror 101 is condensed by the condenser lens 103 to illuminate the microfilm 104, and the image light thereof is transmitted through the coupling lens 105 and the mirrors 106 and 107. The information is projected on the screen 108 and the information on the microfilm 104 is read. On the other hand, when recording this information on recording paper or the like, the two mirrors 110 and 111 supported by the support 109 and forming an angle of 90 degrees with each other are moved in the direction of arrow P1 so that the mirror 110 is in the reader optical path. After that, the mirrors 110 and 111 are operated in the opposite arrow P2 direction to change the image light, and the photosensitive drum 113 is moved through the slit 112a formed by the slit plate 112.
Guided above and recorded by known electrophotographic techniques.

By the way, in this type of reader printer,
The type of the imaging lens 105 that has been replaced, the difference in zoom magnification,
Due to variations in the document illumination lamp 102, the screen 1
08, unevenness of the light amount occurs on the photosensitive drum 113.

In such a printer, the slit plate 112 has a curvature to compensate for the uneven light amount in the drum axis direction, thereby compensating for the insufficient light amount at the end portion.

Further, with respect to the unevenness of the light amount in the scanning direction, a projection lens is attached and a zoom magnification detecting means is provided, and the lamp voltage is controlled so that the illuminance of the photosensitive drum surface becomes constant according to the detected magnification. Was.

[0007]

However, when the light amount of the document illumination lamp is controlled in accordance with the type of lens and the zoom magnification, the distribution of the light amount unevenness is caused by the variation of the document illumination lamp 102 and the coupling lens 105. It often changes, and as a result, it was not possible to perform accurate correction of uneven light amount.

An object of the present invention is to solve the above problems and to provide a reader printer capable of correcting uneven light amount more accurately.

[0009]

[Means for Solving the Problems]

1) A reader printer according to the present invention comprises a light source for illuminating a document, a means for projecting an image on an information recording medium illuminated by the light source, and a means for exposing and recording an image carrier according to the image information. In the reader printer having the storage means, which stores the previously obtained light amount unevenness degree coefficient and the unevenness correction table in association with each other, and the image carrier of the transmitted light of the information recording medium illuminated by the light source during prescanning. Detecting means for detecting the light quantity in the scanning direction, calculating means for calculating a light quantity unevenness degree coefficient from the distribution of the light quantity detected by the detecting means, and unevenness corresponding to the light quantity unevenness degree coefficient calculated by the calculating means Search means for searching the correction table and controlling the light quantity of the light source during the main scan according to the unevenness correction table searched by the search means. And a control means for controlling.

2) In the reader printer according to the above 1), the developing bias amount is obtained from the light amount of the scan center portion detected by the detecting means, and the obtained developing bias amount is searched for by the unevenness correction table searched by the searching means. It is characterized by comprising a calculating means for calculating the developing bias amount in the entire main scan by multiplying by the coefficient.

[0011]

In the present invention, the amount of transmitted light of the information recording medium illuminated by the light source during the prescan in the scanning direction of the image carrier is detected by the detecting means, and the degree coefficient of the unevenness of the amount of light is calculated from the distribution of the detected amount of light. The unevenness correction table calculated by the calculation means and corresponding to the calculated light intensity unevenness degree coefficient is searched from the storage means by the search means, and the light quantity of the light source is controlled by the control means at the time of the main scan in accordance with the searched unevenness correction table.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

<First Embodiment> FIG. 1 shows a first embodiment of the present invention. This is an example of a reader printer, and its configuration is shown in FIG.
Shown in

In FIG. 2, a microfilm 1 as an information recording medium includes a lamp 2 as a light source and a spherical reflecting mirror 3.
And is illuminated by an illumination means composed of a condenser lens 4,
At the time of the reader, the image light of the film 1 passes through the projection lens 5 located above it, is further reflected by the plane mirrors 6 and 7 located above, and is projected on the screen 8 as a display means.

The mirrors 9 and 10 are fixedly supported on the lower surface of the support 11 in a relationship intersecting at a right angle, and at the time of copying,
First, the support 11 moves forward in the direction of arrow B1 integrally with the mirrors 9 and 10 (prescan), and the mirror 9 advances while crossing the reader optical path. The light amount of the lamp 2 is kept constant during the prescan. After that, it is moved back (main scan) in the direction of arrow B2 from the exposure start point. At this time, the projection lens 5
The image light that has passed through is reflected by the plane mirrors 9 and 10, and is exposed on the photosensitive drum 12 through the slit 13a of the slit plate 13 provided immediately above the photosensitive drum 12 as an image carrier.

Around the photosensitive drum 12, in addition to a developing device (not shown), a known electrophotographic primary charger, a transfer charger, and the like are provided. The photosensitive drum 12 rotates in the direction of arrow A at a constant speed during image exposure, and the mirrors 9 and 10 move at a speed half the peripheral speed of the photosensitive drum 12. After the exposure, the support 11 returns to the initial position where it can be used as a reader and stops.

A substrate 14 is disposed on the slit plate 13, and six light receiving elements are provided on the substrate 14 for the photosensitive drum 1.
In order to reduce the influence of unevenness in the axial direction (scanning direction) of 2 as much as possible, they are arranged near the center as shown in FIG. The substrate 14 is arranged on the slit plate 13 as follows.
This is because it is necessary to deal with a change in the illuminance on the photosensitive drum 12 caused by a difference in the transmittance of the replaced projection lens 5 or a difference in the type and density of the microfilm 1, and the troublesomeness of density adjustment and so-called running cost. This is to reduce Then, based on the output value obtained by the prescan, the bias amount at the time of development is controlled so that an optimum recorded image can be obtained.

In FIG. 1, reference numerals 2 and 15 denote the same parts as in FIG. The light receiving element group 15 reads the transmitted light of the microfilm 1 during the prescan and sends it to the multiplexer 16. The CPU 18 switches the control signal of the multiplexer 16 and repeatedly outputs the output of the light receiving element group 15 in order. The output of the light receiving element group sent from the multiplexer 16 is amplified by the amplifier 17 and then sent to the CPU 18.

The density data read by the light receiving element group 15 during the prescan is deleted, averaged, and calculated by the CPU 18, the degree coefficient X is obtained, and the optimum value is obtained based on the obtained degree coefficient. A non-uniformity correction table is selected. Then, during the main scan, the lamp regulator 19 controls the light amount of the lamp 2.

Next, the light quantity control of the lamp 2 will be described in more detail.

During the prescan, the light transmitted through the microfilm 1 is read by the light receiving element group 15, and 144 density data are sent from the start to the end of the prescan. Each light receiving element of the light receiving element group 15 is larger in size than the characters of the microfilm 1, and 144 light receiving positions of the light receiving element group 15 with respect to the microfilm 1 are as shown in FIG. The illuminance ratio between the central part and the peripheral part of the original is
The zoom magnification changes as shown in FIG.

The actual microfilm is affected not only by the unevenness of the light amount but also by the characters and dust on the original as shown in FIG. When the light receiving element group 15 receives a character portion, the output of the light receiving element group 15 is very large, and when the dust on the document table is received, the output of the light receiving element group 15 is very small.

Then, the CPU 18 divides the 144 data into three blocks, and deletes 12 large and 12 small data from each 48 data. FIG. 7 shows an example in which the upper and lower two data are deleted for each block. The number of data to be deleted was set to 12 so as not to be affected by the characters on the document and dust on the document table. Further, by obtaining the average light amount for each block and using it as one data, three light amount unevenness data which are not affected by the document contents or dust in the three blocks can be obtained.
Then, the following equation (1), that is,

[0024]

## EQU1 ## X = (((data of block 1) + (data of block 3)) / 2) / (data of block 2) ... (1) is calculated and the degree coefficient X of the unevenness of the light amount is obtained. . Here, in the reader printer, the light amount ratios of the central portion and the peripheral portion of the scan at all zoom ratios of the projection lens 5 are:
The maximum was 65% and the minimum was 95%.

Then, an appropriate table is selected from the three types of unevenness correction tables shown in FIG. That is, (1) If the degree coefficient X> 0.85, the CPU 18 selects the unevenness correction table A, and the lamp regulator 19 controls the lamp 2 based on the selected unevenness correction table A. As a result, the lamp 2 at the center of the scan
Of the lamp intensity at the start or end of scanning
90%.

(2) When 0.85 ≧ degree coefficient X> 0.75,
The unevenness correction table B is selected by the CPU 18, and the lamp 2 is controlled by the lamp regulator 19 based on the selected unevenness correction table B. As a result, the light amount of the lamp 2 at the center of the scan becomes 80% of the lamp light amount at the start or end of the scan. FIG. 9 shows how the light quantity unevenness is corrected.

(3) If 0.75 ≧ degree coefficient X, CPU
The unevenness correction table C is selected by 18, and the lamp 2 is controlled by the lamp regulator 19 based on the selected unevenness correction table C. As a result, the light quantity of the lamp 2 at the center of the scan becomes 70% of the lamp light quantity at the start or end of the scan.

Therefore, it is possible to suppress the unevenness of the light amount after the lamp light amount is corrected within 5% at all zoom ratios.

In this embodiment, the density data read during the prescan is divided into three blocks, and the degree coefficient is calculated by the equation (1). However, the density data is divided into finer blocks, The degree coefficient may be obtained by least-squares approximation.

<Embodiment 2> In Embodiment 1, the light quantity unevenness is corrected by the obtained lamp light quantity. In this embodiment, however, the light quantity unevenness correction and the recording density are simultaneously performed only from the obtained lamp light quantity. adjust. The CPU 18 is 3 shown in FIG.
Select an appropriate table from the different types of unevenness correction tables. That is, (1) When the degree coefficient X> 0.85, the CPU 18 selects the unevenness correction table D, and the lamp regulator 19 controls the lamp 2 based on the selected unevenness correction table D. As a result, the lamp 2 at the center of the scan
Of the lamp intensity at the start or end of scanning
90%.

(2) When 0.85 ≧ degree coefficient X> 0.75,
The unevenness correction table E is selected by the CPU 18, and the lamp 2 is controlled by the lamp regulator 19 based on the selected unevenness correction table E. As a result, the light amount of the lamp 2 at the center of the scan becomes 80% of the lamp light amount at the start or end of the scan. FIG. 9 shows how the light quantity unevenness is corrected.

(3) If 0.75 ≧ degree coefficient X, CPU
The unevenness correction table F is selected by 18, and the lamp 2 is controlled by the lamp regulator 19 based on the selected unevenness correction table F. As a result, the light quantity of the lamp 2 at the center of the scan becomes 70% of the lamp light quantity at the start or end of the scan.

Therefore, it is possible to suppress the unevenness of the light amount after the lamp light amount is corrected within 5% at all zoom ratios.

Block 2 is used for automatic density adjustment of recording paper.
This is performed using the data of (the central part of the scan). That is,
The main scan ramp voltage conversion table shown in FIG. 11 is used to find the main scan ramp voltage from the data in block 2, and the obtained main scan ramp voltage is multiplied by the coefficient of the selected unevenness correction table to obtain the main scan voltage. The voltage of the lamp 2 in the entire scan is calculated.

<Third Embodiment> In the first embodiment, the light amount unevenness is corrected by the obtained lamp light amount. However, in this embodiment, the light amount unevenness is corrected and the recording density is simultaneously obtained only from the obtained lamp light amount. adjust. The CPU 18 is 3 shown in FIG.
Select an appropriate table from the different types of unevenness correction tables. That is, (1) When the degree coefficient X> 0.85, the CPU 18 selects the unevenness correction table G, and the lamp regulator 19 controls the lamp 2 based on the selected unevenness correction table G. As a result, the lamp 2 at the center of the scan
Of the lamp intensity at the start or end of scanning
90%.

(2) When 0.85 ≧ degree coefficient X> 0.75,
The unevenness correction table H is selected by the CPU 18, and the lamp 2 is controlled by the lamp regulator 19 based on the selected unevenness correction table H. As a result, the light amount of the lamp 2 at the center of the scan becomes 80% of the lamp light amount at the start or end of the scan. FIG. 9 shows how the light quantity unevenness is corrected.

(3) If 0.75 ≧ degree coefficient X, CPU
The unevenness correction table I is selected by 18, and the lamp 2 is controlled by the lamp regulator 19 based on the selected unevenness correction table I. As a result, the light quantity of the lamp 2 at the center of the scan becomes 70% of the lamp light quantity at the start or end of the scan.

Therefore, it is possible to suppress the unevenness of the light amount after the lamp light amount is corrected within 5% at all zoom ratios.

Block 2 is used for automatic density adjustment of recording paper.
This is performed using the data of (the central part of the scan). That is,
The development bias amount conversion table for main scan shown in FIG. 13 is used to obtain the development bias amount from the data of block 2, and the obtained development bias amount is multiplied by the coefficient of the selected unevenness correction table to obtain the entire main scan. To obtain the developing bias amount.

[0040]

As described above, according to the present invention,
With the configuration as described above, the light amount unevenness correction can be performed more accurately.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing the configuration of the reader printer shown in FIG.

FIG. 3 is a diagram showing an arrangement example of a light receiving element group 15.

FIG. 4 is a diagram showing 144 light receiving positions of the light receiving element group 15 with respect to the microfilm 1.

FIG. 5 is a diagram illustrating an example of light amount unevenness due to zoom magnification.

FIG. 6 is a diagram showing an example of data affected by characters and dust on a document.

FIG. 7 is a diagram showing an example of data after two pieces of upper and lower data are deleted for each block.

FIG. 8 is a diagram showing an example of an unevenness correction table in the first embodiment.

FIG. 9 is an explanatory diagram for explaining an example of lamp light amount control.

FIG. 10 is a diagram showing an example of an unevenness correction table according to the second embodiment.

FIG. 11 is a diagram showing an example of a lamp voltage conversion table during main scan.

FIG. 12 is a diagram illustrating an example of an unevenness correction table according to the third embodiment.

FIG. 13 is a diagram showing an example of a development bias amount conversion table during main scan.

FIG. 14 is a schematic diagram showing a configuration of a conventional reader printer.

[Explanation of symbols]

 1 Micro Film 2 Lamp 3 Spherical Reflector 4 Condenser Lens 5 Projection Lens 6, 7 Plane Mirror 8 Screen 9, 10 Mirror 11 Support 12 Photosensitive Drum 13 Slit Plate 14 Substrate 15 Photoreceptor Group 16 Multiplexer 17 Amplifier 18 CPU 19 Lamp regulator

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location G03G 15/04 15/06 101 15/22 104

Claims (2)

[Claims] 1. A reader printer comprising a light source for illuminating a document, means for projecting an image on an information recording medium illuminated by the light source, and means for exposing and recording an image carrier according to the image information, A storage unit that stores a previously obtained light amount unevenness degree coefficient and an unevenness correction table in association with each other, and a light amount in the scanning direction of the image carrier of the transmitted light of the information recording medium illuminated by the light source during prescanning. A detection unit for detecting, a calculation unit for calculating a light intensity unevenness degree coefficient from the distribution of the light intensity detected by the detection unit, and a nonuniformity correction table corresponding to the light intensity unevenness degree coefficient calculated by the calculation unit are searched. Search means and control means for controlling the light quantity of the light source during the main scan according to the unevenness correction table searched by the search means. Reader printer, characterized in that was example. 2. The developing bias amount is obtained from the light amount of the scan central portion detected by the detecting unit, and the coefficient of the unevenness correction table searched by the searching unit is added to the obtained developing bias amount. A reader printer, comprising: a calculating unit that calculates a developing bias amount for the entire main scanning.