JPH0561625B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electrophotographic apparatus using the so-called Carlson process for copying an image of a document surface onto plain paper, and more specifically, by specifying a position on the document surface. 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 can perform various processing on the copied image according to the specified position.

Structure of a conventional example and its problems FIG. 1 shows a schematic structure of a main part of an example of a conventional electrophotographic apparatus using the Carlson process. In FIG. 1, the photoreceptor 10 is rotated in the direction of the misprint 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 lamp 20 serving as an original irradiation means, and a reflected image thereof is formed on the photoreceptor 10 through an imaging optical system such as an optical fiber 22 having a lens effect. , the document surface 18 in synchronization with the rotation of the photoreceptor 10.
The original surface images are sequentially exposed onto the photoreceptor 10 from the right end to the left end. In the developing device 24, toner is attached according to the charge distribution of the electrostatic latent image generated on the photoreceptor 10 by exposure of the original image, and a developed image is formed on the photoreceptor 10. This developed image is transferred onto the copy paper 11 by the transfer charger 25 to form a copy image.

Incidentally, when obtaining a copy image, there is a desire to perform various processing on the image, such as adjusting the density, erasing a specific part of the image, or 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 lamp 20, and the exposure from this fluorescent lamp 20 is the exposure of the reflected image from the document surface 18. Direct photoreceptor 10
There is no irradiation means to irradiate. For this reason, the photoreceptor 10
Although it is possible to reduce the amount of exposure to the image, increasing the amount of exposure requires a significant increase in the amount of light emitted from the fluorescent lamp 20, which is impractical, and it is difficult to erase specific portions of the original image. However, since a light source such as a fluorescent lamp is used, there are problems such as it is difficult to divide the area according to the specified position and adjust the exposure amount. That was difficult.

Purpose of the Invention The present invention eliminates the drawbacks of the conventional example 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 possible to perform various processing on the copied image according to the specified position, and
An object of the present invention is to provide an electrophotographic device that can clarify the outline of a processed copy image.

Structure of the Invention The present invention provides an original irradiation means for performing primary exposure by irradiating a document surface with light to obtain a reflected image, and an image forming unit for forming the reflected image of the document surface as a latent image on a photoreceptor. an optical system, a photoconductor irradiation means as a secondary exposure source that irradiates light onto the photoconductor surface, an indicator pen that specifies a position by pressing an arbitrary position on the document surface, and coordinate input means comprising a position detection plate having a detection surface corresponding to the document surface and detecting a position pressed by the pointing pen on the document surface; a function specifying means for selecting and specifying a desired function from various image processing functions to perform desired image processing by irradiating light and changing the charge distribution of the latent image on the photosensitive surface; control means for controlling the operation of at least the photoreceptor irradiation means to perform the function designated by the function designation means in accordance with the signal of the position on the document surface detected by the position detection plate; The document is placed facing upward on the detection surface of the position detection plate, and the desired position of the document is determined by pressing the detection surface of the position detection plate through the document with the indicator pen. on the document surface, as well as the area on the document surface specified by the pointing pen and the position detection plate, and the area on the document surface selected and designated by the function specifying means. According to the image processing function to be applied to the area, the light irradiation operation of the photoreceptor irradiation means is controlled to perform secondary exposure, and the primary exposure and the secondary exposure are overlapped, thereby The exposure amount to the photoconductor can be changed according to the position on the document surface that is directly indicated and detected by the indicator pen and the position detection plate, and the photoconductor The irradiation means is provided with a diffusion regulating means for regulating the diffusion of light, and the coordinate input means is configured to:
including the function specifying means, and providing the coordinate input means and the control means as separate members from the main body of the copying machine;
The coordinate input means is configured to be connected to the photoreceptor irradiation means via the control means.

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. Fluorescent lamp as irradiation means 2
0, an optical fiber 22 having a lens effect as an imaging optical system, a developing device 24, and a transfer charger 25 are provided. The document table 26 moves in the direction of an arrow 28 in synchronization with the rotation of the photoconductor 10, so that the document image is sequentially transferred to the photoconductor 10 from the right end to the left end of the document surface 18 placed on the document table 26. The top is exposed.

Similar to the 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 charge distribution of the electrostatic latent image is formed by the developing device 24. Accordingly, toner adheres to form a developed image on the photoreceptor 10. In this embodiment, the photoreceptor 10 is further placed between a fluorescent lamp 20 serving as an original irradiation means and a developing device 24. A light emitting diode array 30 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 for directly irradiating light. 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 diodes 29. A control circuit 32 for controlling the amount of current supplied to the light emitting diodes 29 via a flexible wiring board 34 connected to array 30; The control circuit 32 further includes a position detection plate 38 as a position detection means for placing one document 16 and detecting a designated position on the placement surface 36 of the document 16, and a position detection plate 38 for detecting a designated position on the placement surface 36 of the document 16; An instruction panel 40 for selecting and specifying various functions is connected. The position detection plate 38 has an indicating pen 4 as a position indicating means for indicating the position on the mounting surface 36.
2 are connected. The position detection plate 38 is formed with orthogonal coordinates consisting of an X-axis and a Y-axis, with the coordinate origin 44 as the source point. The X-axis and Y-axis are divided at a required interval, and it is possible to coordinate the position on the position detection plate 38 in the XY plane defined by the X-axis and Y-axis. The original 16 is placed on the position detection plate 38 with one end aligned with the coordinate origin 44, the original surface 18 facing upward, and the edges of the original along the X and Y axes. Note that the position detection plate 38 and the pointing pen 42 are electromagnetically coupled to each other, forming a so-called electromagnetic induction type coordinate input device.

Next, the point on the position detection plate 38 by the indicator pen 42 is
An example of position specification within the XY plane will be explained with reference to FIG. First, point two points A using the pointing pen 42.
By pressing the position detection plate 38 at the positions (X ₁ , Y ₁ ) and C (X ₂ , Y ₂ ), the two points A and C are input to the control circuit 32, and based on this input, the positions shown in FIG. Points A (X ₁ , Y ₁ ), B (X ₂ , Y ₁ ), C (X ₂ ,
Y ₂ ), D(X ₁ , Y ₂ ) is calculated and stored as a designated position. On the instruction panel 40, for example, the above-mentioned rectangular area ABCD is left and the other document surface images are erased. The document surface image corresponding to the rectangular area ABCD is erased and left in the other areas. The copy image density of the document surface image corresponding to the rectangular area ABCD is reduced. Key switches 46a, 46b, 41c, etc. are provided for selecting and specifying the desired image processing method, and the necessary image processing method is selected using these keys.

The original 16, whose position on the original surface has been specified as described above, is moved from the original surface 18 to the original placing surface 48.
The document is transferred onto the document table 26 so as to face the document. At this time, the document placement surface 48 is placed at a starting point 50 where the phase of the document table 26 and the phase of the photoconductor 10 match when exposing the document surface image to the photoconductor 10.
An orthogonal coordinate is formed by the X' axis and the Y' axis, and when the original 16 is transferred, the original 16 is aligned with the coordinate origin 44 on the position detection plate 38.
Original 1 aligned with the upper end point and the X and Y axes
By aligning the edges of 6 with the starting point 50, the X' axis, and the Y' axis, the coordinates on the position detection plate 38 and the coordinates on the document table 26 are matched, and the document table 2
It is possible to maintain consistency between the starting point 50 on 6 and the photoreceptor. Although the connection relationship is not shown in the figure, the control circuit 32 also has a control function for the entire electrophotographic apparatus other than the light emitting diode array 30 through the wiring group 52.

Next, a copying operation in this embodiment will be described using as an example a case where an attempt is made to erase a document surface image corresponding to a rectangular area ABCD specified by the above-described procedure. First, a first exposure is performed by the fluorescent lamp 20 to sequentially expose the reflected image of the document surface 18 on the photoconductor 10, and an electrostatic latent image corresponding to the document surface image is formed on the photoconductor 10. . Thereafter, a second exposure is performed directly on the photoreceptor 10 by the light emitting diode array 30, and the first exposure and the second exposure are superimposed. In the second exposure, a rectangular area on the document surface is The light emitting diode 29 provided between the widths X ₁ and X ₂ corresponding to ABCD forms a rectangular area.
The control circuit 32 controls the light to be turned on only during the lengths Y ₁ and Y ₂ corresponding to ABCD with an amount of light that can erase the electrostatic latent image corresponding to the image on the document surface. An electrostatic latent image on the document surface 18 is formed by the first exposure, and the electrostatic latent image in a portion corresponding to the rectangular area ABCD is erased by the second exposure. It is developed to form a visible image.

By the way, the light emitting diode 29 is a diffusive light source. Therefore, there is a possibility that the electrostatic latent image in an area wider 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 irradiation distribution on the irradiation surface 57 when the light emitting diode 29 irradiates light at an angle θ ₁ , where the vertical axis is the illuminance and the horizontal axis is the width of the irradiation surface. As shown in the figure, the illuminance of the irradiation surface 57 is not constant, but decreases as the distance from the center of the light emitting diode 29 increases. Therefore, when the illuminance required to erase the electrostatic latent image on the photoreceptor 10 is L (lux), the illuminance at the point 54 or 56, which forms the outline of the image to be erased, is changed slowly. Therefore, the outline of the erased image may not be clear and the erased portion may become wide.

Therefore, a slit 58 as a diffusion control means as shown in FIG. 5 is installed on the light emitting surface of the light emitting diode array 30. The slits 58 are provided with openings in the light emitting surface of each light emitting diode 29 at a pitch equal to the pitch l of the light emitting diode 29, and
It is configured to block part of the light from the photoreceptor 10 in both the main scanning direction and the sub-scanning direction. The details at this time will be explained using the drawings.

FIG. 6 shows that when the light emitting diode 29 emits light at an angle θ ₁ as in FIG. 4, the slit 58 shown in _FIG . This is a diagram showing the illuminance distribution of the irradiated surface 57 when light is irradiated at an angle of θ ₂ <θ ₁ ), where the vertical axis is the illuminance and the horizontal axis is the width of the irradiated 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 57 is not uniform, and the illuminance decreases as it moves away from the center of the light emitting diode 29. However, by installing the slit 58, the illuminance changes rapidly at the point 60 or 62, which is the outline of the image to be erased, so the outline of the erased image becomes clear and the erased part is It won't get wider.

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 the rotation direction 12 to be switched in a predetermined time width, the photosensitive surface of the photoreceptor 10 can be divided into a plurality of pixel areas with clear outlines, and the pixels can be divided into a plurality of pixel areas with clear outlines. It becomes possible to perform image processing for each unit pixel as a unit.

Note that in the above example, the portion corresponding to the rectangular area ABCD was erased, but the light emitting diode array 30
The second exposure can also act as bias exposure for the photoreceptor 10, and by selecting the required amount of light emission from the light emitting diode 29, the total exposure amount of the document portion corresponding to the rectangular area ABCD is increased. can be done. By this,
To reduce 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 to lower the density of the developed image formed by the developing device 24. Therefore, when copying an original whose background density is only within the rectangular area ABCD, the rectangular area
It is possible to selectively remove so-called fog in the copied image of the ABCD portion.

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, setting the maximum exposure amount of this second exposure to be greater than or equal to the exposure amount necessary to erase the residual charge on the photoreceptor 10 also has the advantage that it can be easily realized. have

As described above, according to this embodiment, there is provided an indicator pen that can input an arbitrary position on the document surface, and a position detection board that can detect an arbitrary position of the document input by the indicator pen. , an instruction panel for specifying image processing, a light emitting diode array for second exposure, a slit for regulating the diffusion of light from the light emitting diodes, and a control circuit for controlling the operation of the light emitting diode and the entire electrophotographic device. By adding it to an electrophotographic device, it is possible to erase or leave a desired area of a document, or change the density of a desired area, and to clarify the outline of the area. This has achieved the effect of being able to.

Effects of the Invention As described above, the present invention is achieved by accurately regulating the irradiation area of the secondary exposure using the diffusion regulating means according to the area on the document surface that is accurately specified by the coordinate input means. Therefore, it is possible to control the density of a desired area of the original, and to clarify the outline of the copied image of the desired area of the original.

Further, in the present invention, the coordinate input means includes a function specifying means as a part thereof, and by providing the coordinate input means and the control means as separate members from the main body of the copying machine, the coordinate input means can be operated using an indicating pen and a position detection plate. The coordinate input means can centrally perform the operation of accurately specifying a desired area of the document and the operation of selecting and specifying a desired function from various image processing functions in the function specifying means, and the coordinate input means can be controlled by the control means. is connected to the photoreceptor irradiation means, which is a secondary exposure source, through the The photoreceptor irradiation means, which is an exposure source, is controlled, making it possible to control the density of a desired area of the document. Furthermore, the diffusion of the light from the secondary exposure source is controlled by the diffusion control means, and the desired area of the original on the photoreceptor is accurately applied according to the area on the original surface precisely specified by the coordinate input means. It is possible to irradiate light corresponding to the area of the document to clarify the outline of the copied image in a desired area of the document.

[Brief explanation of the drawing]

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 distribution of illuminance on the irradiation surface, and FIG. 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, 1
6... Original, 18... Original surface, 20... Fluorescent light,
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 board,
40... Instruction panel, 42... Instruction pen, 44...
...Coordinate origin, 46a-46c...Key switch,
48... Document placement surface, 50... Starting point, 52... Wiring group, 54-56... Points forming the outline of the image after processing, 57... Irradiation surface, 58... Slit, 60-
62... Point that becomes the outline of the image after processing.

Claims (1)

[Scope of 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 as a latent image on a photoreceptor; A photoconductor irradiation means having a plurality of minute light sources arranged in an array in the width direction of the photoconductor as a secondary exposure source for irradiating light onto the photoconductor surface; an indicator pen for specifying a position, a position detection plate having a detection surface corresponding to the original surface of the original document and detecting a position pressed by the indicator pen on the original surface; A desired function is selected from various image processing functions in order to perform desired image processing by irradiating the photoreceptor with light and changing the charge distribution of the latent image on the photoreceptor.
a coordinate input means comprising a function specifying means; and a function specified by the function specifying means according to a signal of a position on the document surface detected by the pointing pen and the position detection plate. and control means for controlling at least the operation of the photoreceptor irradiation means, the document is placed facing upward on the detection surface of the position detection plate, and the position detection is performed by passing the document through the document with the pointing pen. An operation of directly instructing a desired position of the document on the document surface by pressing the detection surface of the plate, and selecting a desired function from various image processing functions by the function specifying means. - By performing a specifying operation on the coordinate input means, the area on the document surface specified by the pointing pen and the position detection plate, and the document selected and specified by the function specifying means. The light irradiation operation of the photoreceptor irradiation means is controlled in accordance with the image processing function to be applied to the area on the surface to perform secondary exposure, and the primary exposure and the secondary exposure are overlapped. The amount of exposure to the photoreceptor can be changed according to the position on the document surface that is directly indicated and detected on the document surface by the indicator pen and the position detection plate, and In the photoconductor irradiation means, the light emitting part of the minute light source constituting the photoconductor irradiation section is located as a separate member from the frame of the minute light source, and the irradiation angle of the minute light source is made small. , the irradiation area of the photoreceptor by the minute light source corresponds to the size of one pixel of an image to be subjected to image processing, and the boundary between the irradiation area and non-irradiation area of the photoreceptor by the minute light source is clearly divided. A diffusion regulating means is provided for regulating the irradiation angle of light both in the width direction of the photoconductor and in the rotational direction of the photoconductor, and the coordinate input means is provided as a separate member from the main body of the copying machine, and An electrophotographic apparatus characterized in that a coordinate input means is connected to the photoreceptor irradiation means via the control means. 2. The electronic photograph according to claim 1, wherein the diffusion regulating means is a plate material interposed between the photoreceptor and the minute light source and configured to regulate the diffusion of light by blocking light. Device.