JPS6120964A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To obtain pictures having distinct outlines by superposing two exposures and changing the exposure in accordance with the position on an original surface detected by a position detecting means and providing a means which controls diffusion of the exposing light. CONSTITUTION:The image of an original surface 18 is exposed on a photosensitive body 10 by a fluorescent lamp 20, and the second exposure is performed by a light emitting diode array 30. In this second exposure, an area to be erased, for example, a rectangular area ABCD on the original surface 18 is selected on a position detecting plate 38 by a pen 42, and the array 30 is controlled by a control circuit 32 to expose a part corresponding to the area ABCD, and an electrostatic latent image in this part is erased, and a photosensitive body 10 is developed by a developing device 24. A slit 58 is provided on the light emitting face of the array 30 to control the diffusion, and the photosensitive face is divided to picture elements areas having distinct outlines. Consequently, exposure to the photosensitive body is controlled in accordance with the designated position on the original surface, and each unit picture elements are subjected to image processing to obtain pictures having distinct outlines.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electrophotographic apparatus that uses the so-called Carlson process to copy an image of a document surface onto a sheet of paper, and more specifically, to The present invention relates to an electrophotographic apparatus that can control the amount of exposure to a photoreceptor according to the specified position on the document surface, and thereby perform various processing on the copied image according to the specified position.

Conventional Structure and Its Problems FIG. 1 shows a schematic structure of the main parts of an example of a conventional electrophotographic apparatus using the Carlson process. In FIG. 1, the photoreceptor 10 rotates in the direction of an arrow 12 when copying is performed, and first, a charger 14 applies a uniform charge to the surface by corona discharge. The original surface 18 of the original 16 is irradiated with light by a fluorescent pair 2o as an original irradiation means, and a reflected image thereof is formed on the photoreceptor 1o through an imaging optical system such as an optical fiber 22 having a lens effect.
In synchronization with the rotation of the photoreceptor 1o, the original surface image is sequentially exposed on the photoreceptor 1o from the right end to the left end of the original surface 18. In the developing device 24, toner adheres to the charge plate of the electrostatic latent image generated on the photoreceptor 1o by exposure of the original image, and a developed image is formed on the photoreceptor 1o. This developed image is transferred onto the copy paper 11 by the transfer charger 26 to form a copy image.

By the way, in order to obtain a copy image, there is a need to perform various processing on the image, such as adjusting the density of the image, erasing a specific part of the image, or conversely leaving a certain part of the image.

However, in the conventional electrophotographic apparatus, the exposure light source for the photoreceptor is only a single fluorescent pair 20, and the exposure from this fluorescent pair 20 is the exposure of the reflected image from the document surface 18. However, there is no irradiation means for directly irradiating the photoreceptor 10.

Therefore, although it is possible to reduce the amount of exposure to the photoreceptor 10, increasing the amount of exposure requires a significant increase in the amount of light emitted from the fluorescent pair 20, which is not practical. Even if you try to erase the original image, since a light source such as a fluorescent pair is used, there are problems such as it is difficult to divide the area according to the specified position and adjust the exposure amount. It was difficult to perform image processing.

Purpose of the Invention The present invention eliminates the drawbacks of the conventional examples as described above, and by specifying the position of the document, the exposure to the photoreceptor is controlled according to the specified position on the document surface. It is an object of the present invention to provide an electrophotographic apparatus that can perform various types of processing on a copied image according to the designated position and that can clarify the outline of the processed copied image.

Structure of the Invention The present invention provides an original irradiating means for irradiating a document surface with light to obtain a reflected image, an imaging optical system for forming a reflected image of the document surface on a photoreceptor, and a method for forming a reflected image on the photoreceptor surface. The document has a photoreceptor irradiation means for irradiating light, a diffusion regulating means for regulating the diffusion of light from the photoreceptor irradiation means, a position specifying means, and a placement surface for placing an original on the placement surface. position detecting means for detecting the position indicated by the position indicating means on the document surface; function specifying means for selecting and specifying a control function for the image; control means for controlling the operation of at least the photoreceptor irradiation means to perform the function specified by the function specification means according to the signal at the upper position;
and a first exposure of the original surface image onto the photoreceptor by the original irradiation means and the imaging optical unit by the control means;
performing a second exposure of the photoreceptor by the photoreceptor irradiation means, and exposing the photoreceptor according to the position on the document surface detected by the position detection means by overlapping the first exposure and the second exposure; By arranging the diffusion regulating means between the photoreceptor irradiation means and the photoreceptor, it is possible to perform various processing on the copied image, and the position specifying means The configuration is such that the outline of the copied image after processing the image of the designated document surface can be made clear.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 is a perspective view of essential parts showing the structure of an embodiment of the electrophotographic apparatus of the present invention. In FIG. 2, when copying, a photoconductor 10 rotates in the direction of an arrow 12, a charger 14 is placed around the photoconductor 10, and a document surface 18 of a document 16 placed on a document table 26 is irradiated with light. A fluorescent lamp 20 as an irradiation means; an optical fiber 22 having a lens effect as an imaging optical system; Developing device 24. Transfer charger 25
is provided. The document table 26 moves in the direction of an arrow 28 in synchronization with the rotation of the photoreceptor 10, so that the image of the document surface is sequentially moved from the right end to the left end of the document surface 18 placed on the document table 26 on the photoreceptor 10. It is exposed to light.

Similar to a conventional electrophotographic apparatus, an electrostatic latent image is formed by applying an electrostatic charge to the photoreceptor 10 and exposing the image on the document surface, and the developing device 24 develops toner according to the charge distribution of the electrostatic latent image. is attached to form a developed image on the photoreceptor 10. In this embodiment, the photoreceptor 10 is directly irradiated with light between a fluorescent lamp 2o as an original irradiation means and a developing device 24. A light emitting diode array 3o in which a large number of light emitting diodes 29 are arranged in an array along the width direction of the photoreceptor 10 is provided as a photoreceptor irradiation means. The amount of light emitted from the light emitting diode array 30 can be arbitrarily set by the amount of current supplied to the light emitting diode 29, and a control circuit 32 for controlling the amount of current supplied to the light emitting diode array 3o via a flexible wiring board 34. It is connected to the.

The control circuit 32 further includes a position detection plate 38 as a position detection means for placing one document 1e and measuring a designated position on the placement surface 36 of the document 16, and a position detection plate 38 for detecting a specified position on the placement surface 36 of the document 16, and a Instruction panel 4 for selecting and specifying various functions
o is connected.

An indicating ben 42 serving as a position indicating means for indicating a position on the mounting surface 36 is connected to the position detection plate 38 . On the position detection plate 38, orthogonal coordinates are formed with the coordinate origin 44 as the origin and consisting of an X axis and a Y axis. The X-axis and Y-axis are divided at a required interval, and the position on the position detection plate 38 defined by the X-axis and Y-axis within the xY plane can be determined as coordinates. The original 16 has one end aligned with the coordinate origin 44 and the original surface 18 facing upward.
And position detection plate 38 so that the edge of the document is along the X axis and Y axis
placed on top. In addition, the position detection plate 38° indication ben 42
are electromagnetically coupled to each other. This constitutes a so-called electromagnetic induction type coordinate input device.

Next, an example of position designation in the xy plane on the position detection plate 3B using the pointing ben 42 will be explained with reference to FIG. first,
2 points A (Xl. by instruction Ben 42).

By pressing the position detection plate 38 at the position Y, ), C (x2.Y2), two points A and C are input to the control circuit 32, and based on this input, the points A and C are indicated by diagonal lines in FIG. Point A (Xl
, Yl), B(x2.Yl), C(x2.Y2), D
The rectangular area surrounded by (xl, Y2) is calculated as 3 and stored as the specified position. The instruction panel 40 includes, for example, ■
Leaving the aforementioned rectangular area ABCD, the other document surface images are erased. ■ Erase the document surface image corresponding to the rectangular area ABCD and leave the other parts. ■ Rectangular area AB
The density of the copy image of the original surface image corresponding to the CD is reduced.

Key switches 46a, 46b, 46c, etc. are provided for selecting and specifying the required image processing method.

The original 1p, whose position on the original surface has been designated as described above, is transferred onto the original table 26 with the original surface 18 facing the original placing surface 48.

Ru. At this time, the photoreceptor 10 of the document surface image is placed on the document placement surface 48.
An orthogonal coordinate is formed by the X' axis and the Y axis, with the starting point 5o where the phase of the original platen 26 matches the phase of the photoreceptor 10 during exposure to the original 16, and position detection is performed when the original 16 is transported. Position detection is performed by aligning the end point on the original 16 that is aligned with the coordinate origin 44 on the plate 38 and the edge of the original 16 that is aligned with the X-axis and Y-axis with the starting point so, the X'-axis, and the Y'-axis, respectively. It is possible to maintain the consistency between the coordinates on the plate 38 and the coordinates on the document table 26, as well as the correspondence between the starting point 6o on the document table 26 and the photoreceptor. In addition,
Although the connection relationship of the control circuit 32 is not shown in the diagram, the wiring group 5
2 also has a control function for the entire electrophotographic apparatus other than the light emitting diode array 30.

Next, the rectangular area ABC specified by the above procedure
The copying operation in this embodiment will be explained by taking as an example the case where the document surface image corresponding to D is to be erased.

First, the original surface 1 is sequentially illuminated on the photoreceptor 10 by the fluorescent lamp 20.
A first exposure is performed to expose the reflected image of photoreceptor 10.
An electrostatic latent image corresponding to the original surface image is formed thereon. Thereafter, the light emitting diode array 30 performs a second exposure directly to the photoreceptor 10, and the first exposure and second exposure are superimposed. In the second exposure, a rectangular area on the document surface is Width x1 corresponding to ABCD. The control circuit 32 controls the light emitting diode 29 provided between x2 to be lit only during the length Yl, 72 corresponding to the rectangular area ABCD, with an amount of light emitted that can erase the electrostatic latent image corresponding to the image on the document surface.
controlled by The first exposure forms an electrostatic latent image on the document surface 18, and the second exposure forms a rectangular area ABCD.
The photoreceptor 1o from which the electrostatic latent image has been erased is developed by the developing device 24 to form a developed image.

On the other hand, the light emitting diode 29 is a diffuse light source. Therefore, there is a possibility that the electrostatic latent image in a wider area than the rectangular area ABCD will be erased. Details at this time will be explained using FIG. 4.

FIG. 4 is a diagram showing the illuminance distribution on the irradiation surface 67 when the light emitting diode 29 irradiates light at an angle θ1, where the vertical axis represents the illuminance and the horizontal axis represents the width of the irradiation surface. As shown in the figure, the illuminance of the irradiation surface 67 is not constant, but decreases as the distance from the center of the light emitting diode 29 increases. Therefore, the photoreceptor 10
The illuminance required to erase the electrostatic latent image above is LCllux.
When J, point 64 or point 5 is the outline of the image to be erased.
Since the illuminance of the 60 portion changes slowly, the outline of the erased image may not be clear and the erased portion may become wide.

Therefore, on the surface of the light emitting surface of the light emitting diode array 30,
As shown in Fig. 5, the diffusion control means has a pitch of 29 l.
The openings are provided at a pitch equal to , and are configured to block part of the light in both the main scanning direction and the sub-scanning direction of the photoreceptor 1o. Details will now be explained using the drawings.

In FIG. 6, the light emitting diode 29 is set at an angle θ as in FIG.
1, by installing the slit 58 shown in FIG. 5 on the surface of the light emitting diode 290, the slit 58 shown in FIG.
In the figure, the vertical axis is the illuminance, and the horizontal axis is the width of the irradiation surface. As shown in the figure, even when the slit 58 is installed on the light emitting surface of the light emitting diode 29, the illuminance distribution on the irradiation surface 67 is not uniform, and the illuminance decreases as the distance from the center of the light emitting diode 29 increases. However, slit 68
Because the illuminance changes rapidly at point 60 or point 62, which forms the outline of the image to be erased,
The outline of the erased image becomes clear, and the erased portion does not become wide.

Furthermore, the size of the exposure surface of n (n: an integer of 1 or more) photoreceptors 10 of the light emitting diodes 29 is set as a unit size for dividing the photoreceptor 10 into a plurality of parts in the sub-scanning direction, and By configuring so that switching can be performed in a predetermined time width according to the rotation direction 12, the photoreceptor 1o
The photosensitive surface can be divided into a plurality of pixel areas with clear outlines, and image processing can be performed for each unit pixel, using the pixel as a unit.

Note that in the above example, the portion corresponding to the rectangular area ABCD was erased, but the second exposure by the light emitting diode array 30 can also act as bias exposure to the photoreceptor 1o, and the amount of light emitted from the light emitting diode 29 is adjusted to the required amount. By selecting , it is possible to increase the total exposure amount of the document portion corresponding to the rectangular area ABCD. This reduces the residual charge only in the portion corresponding to the rectangular area of the electrostatic latent image formed by the first exposure by the fluorescent lamp 20, and reduces the density of the developed image formed by the developing device 24. Therefore, when copying a document in which only the rectangular area ABCD has bank ground density, for example, it is possible to selectively remove so-called fog in the copied image in the rectangular area ABCD. - Furthermore, unlike the first exposure in which the light reflected from the original surface 18 is exposed through the optical fiber 22, the second exposure directly exposes the photoreceptor 10, so that copying images can be processed with a relatively small amount of light emitted. Therefore, it is possible to obtain the exposure illuminance necessary for the second exposure, and therefore, it is also advantageous that the maximum exposure amount of this second exposure is greater than or equal to the exposure amount necessary to eliminate the residual charge on the photoreceptor 1o. .

As described above, according to this embodiment, there is provided an indicator pen that can input an arbitrary position on the document surface, a position detection plate that can detect an arbitrary position of the document input by the indicator pen, and an an instruction panel for specifying processing for;
Light emitting diode array as second exposure and light emitting diode “
By adding a slit that regulates the diffusion of light from the LED and a control circuit that controls the operation of the light emitting diode and the entire electrophotographic device to a conventional electrophotographic device, it is possible to erase or leave a desired area of the document. Alternatively, it is possible to change the density of a desired region and to make the outline of the region clear.

Effects of the Invention As described above, the present invention provides a conventional electrophotographic apparatus with a photoreceptor irradiation means for directly irradiating the photoreceptor surface with light, a position indicating means for specifying an arbitrary position on the document surface, and a position indicating means for specifying an arbitrary position on the document surface. a position detecting means for detecting a designated position of the photoreceptor, a control means for controlling the operation of the photoreceptor irradiation means, and a function specifying means for selecting a control function for the image,
Furthermore, by equipping the photoreceptor irradiation means with a diffusion regulating means for regulating the diffusion of light, the amount of exposure to the photoreceptor can be adjusted according to a specified position on the document surface, and various types of processing can be performed on the copied image according to the specified position. It is possible to easily obtain the excellent effect of being able to perform processing and clarifying the outline of the copied image after processing.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of the main parts of a conventional electrophotographic apparatus, FIG. 2 is a perspective view of the main parts of an electrophotographic apparatus according to an embodiment of the present invention, and FIG. 3 is an embodiment of the present invention. FIG. 4 is a plan view showing the position coordinates of the document surface and the area specified by the position coordinates, FIG. 4 is a diagram showing the diffusion of light from a light emitting diode and the illuminance distribution on the irradiated surface, and FIG. 6 is an embodiment of the present invention. FIG. 6 is a front view showing the structure of the light emitting diode and the slit in FIG. 6, and FIG. 6 is a diagram showing the diffusion of light and the illuminance distribution on the irradiation surface when a slit is attached to the light emitting diode in one embodiment of the present invention. 10... Photoreceptor, 11... Copy paper, 12...
... Rotation direction of photoreceptor during copying, 14 ... Charger, 16 ... Original, 18 ... Original surface, 2o
...Fluorescent lamp, 22...Optical fiber, 24...Developer, 25...Transfer charger, 26...Original table, 28. . . . Arrow indicating the direction of movement of the document table during copying, 29 . . . Light emitting diode, 30 . . . Light emitting diode array, 32 . . . Control circuit, 34; ...Flexible wiring board, 36...Placement surface, 38...
Position detection plate, 40... Instruction panel, 42...
...' Fingertip pen, 44... Coordinate origin, 46a
~46c...Key switch, 48...Document placement surface, 50...Start point, 62...Wiring group, 54-56...Processing Points that will become the outline of the image after processing, 57...Irradiation surface, 58...Slid, 60-62...Points that will become the outline of the image after processing. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure R Figure 3 Figure 4 Figure 5 Figure 6

Claims (3)

[Claims] (1) An original irradiating means for irradiating the original surface with light to obtain a reflected image, an imaging optical system for forming the reflected image of the original surface on a photoreceptor, and irradiating light onto the photoreceptor surface. a photoreceptor irradiation means for irradiation, a position specifying means, and a document placement surface, and a position for detecting a position indicated by the position instruction means on the document surface placed on the document placement surface. a detecting means, a function specifying means for selectively specifying a control function for an image, and at least the photosensitive sensor for performing a function specified by the function specifying means according to a signal of a position on the document surface detected by the position detecting means. control means for controlling the operation of the body irradiation means, and the control means causes the original irradiation means and the imaging optical system to first expose the original surface image onto the photoreceptor; A second exposure of the photoreceptor is performed by the irradiation means, and the amount of exposure to the photoreceptor is determined according to the position on the document surface detected by the position detection means by overlapping the first exposure and the second exposure. 1. An electrophotographic apparatus characterized in that the electrophotographic apparatus is configured to be variable and further includes a diffusion regulating means for regulating light diffusion in the photoreceptor irradiation means. (2) The photoreceptor irradiation means is constructed by arranging a plurality of minute light sources in an array, and the diffusion regulating means refers to the rotational direction of the photoreceptor as the main scanning direction, and the axial direction of the photoreceptor is the sub-scanning direction. When referred to as the scanning direction, the invention is characterized in that it is configured to restrict the diffusion of light in both the main scanning direction and the sub-scanning direction of each of the minute light sources constituting the photoreceptor irradiation means. The electrophotographic device according to scope 1. (3) The diffusion regulating means is interposed between the photoreceptor and the minute light source,
3. The electrophotographic apparatus according to claim 1, wherein the electrophotographic apparatus is a plate material configured to restrict light diffusion by blocking light.