JPH01116571A - Image forming 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 [Object of the Invention] (Industrial Application Field) The present invention relates to an image forming apparatus applied to, for example, an electronic copying machine that can copy only a necessary portion of an image.

(Prior art) In recent years, so-called masking copying (first image forming operation), in which an image is formed by erasing an image within a designated range in an original image, and designation copying, in which an image is formed by erasing an image outside a designated range in an original image, are being developed. Electronic copying machines have been developed that are capable of so-called trimming copying (second image forming operation) in which only images within a certain range are formed.

In this type of copying machine, for example, as shown in FIG. By irradiating light from an erasing array (erasing means) 150 provided on the photoreceptor 10 and removing a part of the charge imparted to the surface of the photoreceptor 10 by the charging action of a charging device (not shown),
Some devices are designed to copy a portion of an image (masking copy or trimming copy). In this case, the erasing array 150 includes adjacent light emitting elements 152 . The distance between the centers of the light emitting elements 152, . . . is 5 mm, for example, and the light from each light emitting element 152, . For example, by lighting only the light emitting element C, the electric charges in the area (non-image forming area) a can be removed in a width of 10 mm.

In such a copying machine, when performing a masking copy, only the light emitting elements C provided corresponding to the erased portion of the original image as a specified range are turned on among the light emitting elements 152, . . . of the erase array 150. shall be. Then, an area (
The charges in the non-image forming area) a are removed in a width of 10 mm, and the image within the specified range (width of 10 mm) in the original image is erased and an image is formed.

On the other hand, when performing trimming copying, an image is formed on the surface of the photoconductor corresponding to the specified range by lighting up light emitting elements other than the light emitting elements provided corresponding to the area where the original image is formed as the specified range. Charges outside the area are removed, so that only the image within the specified range in the original image is formed.

That is, in trimming copying and masking copying, the non-image forming area from which charges are removed and the image forming area from which charges are not removed have an inverse relationship with respect to the specified range. Therefore, for example, the area a corresponding to the specified range above
When attempting to form an image only within a specified range (10 mm width) by leaving charges on the surface of the photoreceptor 10 in a width of 10 mm, the light emitting elements 15 of the erasing array 150
2. By lighting up the light emitting elements C other than the light emitting elements C provided corresponding to the formation area of the original image as the specified area, the image forming area other than the image forming area corresponding to the above specified area on the surface of the photoreceptor 10 is turned on. As a result, only the designated range (10 mm width) of the original image is formed.

However, as shown in FIG. 16, in reality, among the light emitting elements 152 of the erasing array 150, only turning off only the light emitting elements C provided corresponding to the area where the original image is formed as a specified range does not result in exposure to light. There was a problem in that it was not possible to trim the 10 mm wide area a corresponding to the specified range on the surface of the body 10.

As described above, in the conventional apparatus, when forming an image by erasing a part of the original image, the adjacent light emitting elements 152 . Because the light from ... is superimposed on each other, the boundaries between the image forming area and non-image forming area will not match when trimming the same designated area and when masking, making it difficult to accurately erase parts of the image. The disadvantage was that it could not be done.

(Problems to be Solved by the Invention) This invention solves two problems: when forming an image by erasing a part of the original image, when forming an image by erasing an image within the same specified range, and when forming an image by erasing only a part of the original image. This was done to solve the problem that when forming an image, the boundaries between the image forming area and the non-image forming area do not match, making it impossible to accurately erase parts of the image. The boundary between the image forming area and the non-image forming area can be aligned to match the boundary between the image forming area and the non-image forming area, depending on whether the image is formed by erasing the image within the area or when forming only the image within the specified area. An object of the present invention is to provide an image forming apparatus that can perform erasing.

[Structure of the Invention] (Means for Solving the Problems) In the image forming apparatus of the present invention, a plurality of light emitters are provided, and the light from the adjacent light emitters is superimposed by the erasing means. A first image forming operation in which an image is formed by erasing an image within a specified range in the original image by removing a part of the charge applied to the surface of the image carrier by irradiating the image with In an image forming apparatus capable of a second image forming operation of forming only an image within the range, during the first image forming operation, a light emitting body provided corresponding to the inside of the specified range is turned on, and the above-mentioned When the second image forming operation is performed by providing a control means for lighting up a light emitting body provided outside the specified range, and using this control means to perform the above first image forming operation for the same specified range. The lighting of the light emitting body is controlled in order to match the boundaries between the image forming area and the non-image forming area in both the second image forming operation and the second image forming operation.

(Operation) The present invention includes a first image forming operation in which an image is formed by erasing an image within a specified range in an original image, and a second image forming operation in which an image is formed in a tree within a specified range in the original image. In this case, the erased portion of the original image and the non-image forming area on the image carrier are in a one-to-one relationship with respect to the specified range.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 9 shows a schematic configuration of an electronic copying machine according to the present invention which is capable of forming an image by erasing a part of the original image. This electronic copying machine includes a copying machine main body 1, a document transport device 2 which is provided on the top surface of the copying machine main body 1 so as to be freely openable and closable, and which automatically supplies original paper, and a loading table on which the copying machine main body 1 is placed. It also receives the paper P ejected from the output section of the copying machine main body 1 as needed, and returns it to the copying machine main body 1 in the same state or with the front and back reversed in order to perform multiple or double-sided copying on the paper P. and a direction changing conveyance device 3 that guides the paper to the paper feeding section.

The copying machine main body 1 has the following configuration. That is, a document table (transparent glass) 5 is provided on the top surface of the housing 4, and a document transport device 2 is provided on the document table 5 so as to be able to be opened and closed so as to cover the top surface of the document table 5. The document is automatically conveyed to the exposure position on the document table 5.

1 on the right side of the housing 4. Paper feed cassettes 6 and 7 are removably installed, and a large-capacity paper feed device 8 is provided corresponding to the right side of the direction conversion conveyance device 3. The cassette cover of the upper paper feed cassette 6 serves as a manual paper feed table 9 for manually feeding paper P as appropriate.

Furthermore, a drum-shaped photoreceptor (image carrier) 10 is disposed approximately at the center of the housing 4 . Around this photoreceptor 10, a charging device 11, an exposure optical system 12, and a developing device 13 are provided.
, transfer charger 14, peeling charger 15, cleaner 16
, and a process system such as a static elimination lamp 17 are sequentially arranged.

Furthermore, in the lower part of the housing 4, there is a paper feed unit 18. . . , the paper 21 manually fed from the manual paper feed tray 9, and the paper P guided from the direction changing conveyance device if3 are transferred between the photoreceptor 10 and the transfer charger 14. A paper transport path 20 is formed that leads to a paper discharge tray 19 provided on the left side of the housing 4 through the image transfer section. A pair of aligning rollers 21 is provided on the upstream side of the image transfer portion of the paper conveyance path 20, and a fixing device (heat roller) 22 and a pair of paper discharge rollers 23 are provided on the downstream side.

The exposure optical system 12 includes an exposure lamp 25 whose back part is surrounded by a reflector 24 and which irradiates light onto the document on the document table 5, and an exposure lamp 25 which reflects light from the document on the document table 5 in a predetermined direction. a first optical unit 27 having a mirror 26 and capable of reciprocating along the document table 5;
a second mirror 29 that moves in synchronization with the optical unit 27 in the same direction at 1/2 the speed of the first optical unit 27 and reflects the light reflected by the first mirror 26 toward the variable magnification lens unit 28; A second optical unit 31 having a third mirror 30 is provided.

Further, at the rear stage of the lens unit 28, there are a fourth mirror 32 and a fifth mirror 33 that reflect the light output from the lens unit 28 in a predetermined direction, and a third optical system whose position is moved according to the set magnification. It is configured to include a unit 34 and a sixth mirror 35 that reflects the light reflected by the third optical unit 34 toward the photoreceptor 10 side.

Note that 36 is a document stopper for stopping the document conveyed by the document conveying device 2 at a predetermined position (exposure position) on the document table 5, and is provided at the left end of the document table 5 with respect to the drawing. ing. The document stopper 36 is configured to be moved up and down by a stopper solenoid (not shown).

The document conveying device 2 includes a supply section 41 that sequentially separates and supplies document sheets set on a paper feed tray 44 one by one, a reversing section 42 that turns the document sheets upside down as needed, and a supply section. The transport section 43 transports the original paper supplied from the original platen 41 to the exposure position on the original platen 5, and discharges the original paper from the original platen 5 onto the paper discharge tray 71 after the exposure is completed. This transport section 43 is provided so as to be openable and closable in correspondence with the document table 5, and also serves as a document table cover.

Thus, the photoreceptor 10 rotates in the direction of the arrow shown in the figure, and the surface is first uniformly charged by the charger 11 for charging. On the other hand, with the exposure lamp 25 turned on, the first optical unit 2
7 moves along the document table 5, and in synchronization with this movement, the second optical unit 31 moves in the same direction at half the speed, so that the document set on the document table 5 is exposed to light. The image of the document (original image) is formed on the photoreceptor 10 by the exposure optical system 12 to form an electrostatic latent image.

The electrostatic latent image formed on the photoconductor 10 is developed by adhering toner to it by facing the developing device 13, and then sent to the image transfer section facing the transfer charger 14, where it is transferred to the photoconductor 10. The upper toner image is transferred onto the paper P supplied via the aligning roller pair 21. Then, the paper P on which the toner image has been transferred is peeled off from the surface of the photoreceptor 10 by the peeling charger 15, and guided through the paper transport path 2o to the fixing device 22, where the toner image is fixed. After the toner image is transferred to the paper P, the surface of the photoreceptor 10 is to face the cleaner 16. The residual toner is cleaned by the charge removal lamp 17, and the charge is removed by the charge removal lamp 17, in preparation for the next copying operation.

Note that when performing multiplex or double-sided copying, by switching the sorting gate 37 provided in front of the pair of paper ejection rollers 23, the sheet P after fixing is not ejected to the paper ejection tray 19, Then, the sheet is guided to the direction changing conveyance device 3, and guided again to the image transfer section by the pair of aligning rollers 21 either as it is or in a reversed state.

FIG. 10 shows an operation panel 50 provided on the main body 1. This operation panel 50 includes a copy key 51 for commanding the start of copying, and a numeric keypad 52 for setting the number of copies, etc.
, a display section 53 consisting of an electronic display tube, etc., which displays the operating status of each part, copy magnification, number of copies, etc., and also displays operating procedures through messages, a copy magnification setting section 54, which sets the magnification, and a select key. Depending on the operation of 55a, overlapping copies of originals or trimming copies (which erase images within a specified range of originals and form images)
An editing section 55 sets a masking copy (first image forming operation) or a masking copy (second image forming operation) that forms only an image within a specified range of the original. It is composed of an operation unit 56 and the like that perform various operations through dialogue.

Here, the operation of specifying a portion of a document to be copied will be explained. When partially forming an image by erasing part of the original, there are two types: masking copy, which erases the image within a specified range and forms the image, and trimming copy, which forms only the image within the specified range. These modes can be selected using the select key 55 of the editing section 55 that constitutes the operation panel 50.
This is done in response to the operation in a. When trimming or masking copying is designated by operating the select key 55a, a display is displayed on the display section 53 to guide the designation of an area indicating the erased portion of the image or the formed portion of the image as the specified range.

For example, as shown in FIG. 11, the area designation is performed with respect to the X-axis direction and the Y-axis direction of the document tray, with respect to the reference point S on the document table 5. mm, X2-? mms and Yl −7 mm.

Based on the display of 7217 mm, each coordinate is set using the numeric keypad 52.

In this case, settings can be made in units of 10 mm, and up to five locations can be set at the same time.
Settings can be easily configured by interacting with the message in . Note that if trimming copy is specified, the area within the specified range is set as the erased part of the image, and the area outside the range is set as the forming part of the image, and if masking copy is specified,
The area outside the specified range is set as the erased portion of the image, and the area within the specified range is set as the formed portion of the image.

On the other hand, as shown in FIG.
Eraser arrays 150 as stages are provided in close proximity. As shown in FIG. 13, this erasing array 150 includes a plurality of light emitters, such as light emitting diodes (L
152.ED). ... are provided at regular intervals.

These light emitting elements 152. . . . are adjacent light emitting elements 152 . The distance between the centers of the elements is, for example, 5 mm, and the erase array 150 includes a total of 62 light emitting elements (LEDI~62) 152.・
... is provided. Then, each light emitting element 1
52. . . is irradiated onto the surface of the photoreceptor 10 after reaching the center position of the adjacent light emitting element 152.

Therefore, one light emitting element 15 in the erase array 150
2, the charge on the photoreceptor 10 can be removed in a width of 10 mm in the direction orthogonal to the direction of rotation of the photoreceptor 10, and the charge removal width (non-image forming (width of the region) is now increased.

The erase array 1-50 is driven by an array driver 160. As shown in FIG. 14, the array driving section 160 includes a shift register, a latch circuit that holds the contents of the shift register, and drives each light emitting element 152, . . . using each output signal of the latch circuit. It is composed of a driver circuit (none of which is shown), and each output terminal (OUT) O of the array drive section 160
0 to 032 are light emitting elements (LEDs 1 to 62) 152 that constitute the erasing array 150. ... are connected to each cathode of each via a resistor R (R1-62). Each of these light emitting elements 152. The anode of ... has a power supply +
5V is supplied to each.

As described above, when the copy key 51 is operated after setting the erased portion of the image according to the specified range for the document sheet, the exposure optical system 12 and the photoreceptor 10 are operated, and the erased portion of the image is operated. A data input signal Sl generated by a control section, which will be described later, corresponding to the clock signal CLK is transferred to the shift register of the array driving section 160. After one line of data input signal SI is transferred to the shift register, when the charged portion of the photoreceptor 10 reaches the erase array 150, the data in the shift register is supplied to the latch circuit in response to the latch signal LT. Ru. Depending on whether the output signal from this latch circuit is high level or low level, each light emitting element 152. By driving..., the light is turned off when it is at a high level, and it is turned off when it is at a low level. The clock signal CLK and latch signal LT are
Both are supplied from the control section in synchronization with the operation of the photoreceptor 10.

In this way, among the charged parts of the photoreceptor 10, the part where the light emitting element 152 is turned on is charged, and even if this charged part (non-image forming area) is subsequently exposed, an electrostatic latent image is formed. This means that the original image has been deleted. Therefore, when forming an image by erasing the image within the specified range, the light emitting elements 152. When trimming copying is performed by removing the charge in the area that corresponds to the erased portion of the image by lighting the light emitting elements 152 . . . . lights up to remove charges in areas other than the area where the image is formed, thereby performing masking copying.

FIG. 1 shows the main part of the control system of the electronic copying machine constructed as described above. That is, the control section 81 mainly controls the copying machine main body 1, and this control section 81 includes operation switches 82 such as various keys on the operation panel 50, a display section 53, and a charger for charging necessary for the copying process. a process system control unit 83 that controls the device 11, the exposure optical system 12, etc.;
A drive system control unit 84 that controls a drive system (not shown) that drives the photoreceptor 10, optical units 27, 31, 34, etc.
, an array driver 160 for driving the erase array 150, and the like are connected to each other.

The control section 81 is mainly composed of a micro-combiner and its peripheral circuits, and is operated according to a program stored in a memory (ROM, not shown).

Further, the control section 81 controls the array drive section 160 and the like based on input from the operation panel 50, thereby controlling each light emitting element 152. ... is turned on in synchronization with the rotation of the photoreceptor 10, and the electric bridge in the area corresponding to the erased part of the image (non-image forming area) is neutralized to form an image only on the necessary part of the document mentioned above. It looks like this.

Next, the operation of such a configuration will be explained using the document printer shown in FIG. 2 as an example. First, a description will be given of a trimming copy in which an image is formed by erasing a designated area (shaded area in the figure) A on a document.

When the copying machine main body 1 is in a ready state (copyable state) and the control unit 81 is in a state where it can accept inputs from various operation switches 82 provided on the operation panel 50,
A document tray is set on the document table 5. Then, when the select key 55a of the editing section 55 is operated as the operation switch 82 of the operation panel 50, the mode is set to the trimming copy mode.

When this mode specification is completed, the specified range A in which the image should be erased is set based on the display on the display unit 53 that is controlled in response to input from the operation switch 82 or the like.

In this case, in response to the operation of the numeric keypad 52, the coordinates X 1 + X 2 in the X-axis direction and the coordinates Y1 . Y2 is input respectively. As a result, the shaded area shown in the figure is set as the designated area A on the original document as the erased area of the image.

After that, when the document cover (conveyance section 43 of document conveyance device 2) is closed and the copy key 51 of the operation panel 50 is operated,
The coordinate data input from the numeric keypad 52 is sent to the control unit 8.
The control unit 81 controls a process system control unit 83, a drive system control unit 84, an array drive unit 160, and the like. That is, the control section 81 controls the drive system control section 84 in response to the operation of the copy key 51, thereby controlling the photoconductor 10 and the optical unit 27, 31.
．． 34 and the like is operated, and by controlling the process system control section 83, the charging device 11, the exposure lamp 25, etc. are operated. Furthermore, each light emitting element 152 . A data input signal SI for driving . . . is generated, and this data input signal SI
is supplied to the array drive section 160 in synchronization with the rotation of the photoreceptor 10.

Here, for example, as the specified range A on the original document, the erased part of the image (the shaded part in the figure) is -10 mm in the Y-axis direction.
Assume that the width is set to be the same as the document width in the X-axis direction. Then, corresponding to the specified range A, each light emitting element 152 . A data input signal SIm (see FIG. 3(a)) for driving . . . is generated and supplied to the array driving section 160.

The data input signal S1m is as shown in FIG.
It is shifted at the rising timing of the clock signal CLK, further changed at the falling timing of the latch signal LT, and held at the rising timing, as shown in FIG. 3(C). Then, in synchronization with the arrival of the charged portion of the photoconductor 10 (see (d) in the same figure), the erase array 1 is
50 light emitting elements 152. ...is output.

As a result, as shown in FIG. 4, the data input signal S
In response to the high level of Im, each light emitting element 152 . ..., only the light emitting element C is lit. As a result, by lighting the light emitting element C, a statically removed non-image forming area a with a width of 10 mm is formed on the surface of the photoreceptor 10.

In this way, the charge is gradually removed by lighting the light emitting element C line by line in the direction of rotation of the photoreceptor 10, and finally the surface of the photoreceptor 10 is covered with the designated area A in the document p.
A non-image forming area a is formed in one-to-one correspondence with . An electrostatic latent image is not formed in this charge-eliminated portion (non-image forming area a) even if it is subsequently exposed, and an electrostatic latent image is formed only in the other portions. Therefore, as shown in FIG. 5, on the paper P ejected from the copying machine main body 1 after the copying operation is completed, the image of the portion corresponding to the specified range A on the document sheet is erased with a width of 1Q mm, and an image is formed. It will be done.

Next, a masking copy in which an image is formed only in a designated area (shaded area in the figure) A on a document will be described.

Similarly to the above, the mode is set to masking copy mode by operating the select key 55a of the editing section 55 of the operation panel 50, and an image is formed by key operations on the operation section 56 and input from the numeric keypad 52. By specifying the desired area, the specified range A (the shaded area in FIG. 2) on the document sheet is set as the image forming area.

After that, when the document cover (conveyance section 43 of document conveyance device 2) is closed and the copy key 51 of the operation panel 50 is operated,
The control unit 81 selects each light emitting element 152 .
A data input signal SI for driving the... is generated, and the process system control section 83 and the drive system control section 84
, the array driver 160, and the like are controlled.

For example, suppose that the specified range A on the original paper is set so that the image forming area (the shaded area in the figure) has a width of 10 mm in the Y-axis direction and the width of the original paper in the X-axis direction. . Then, corresponding to the specified range A, each light emitting element 152 . A data input signal Slt (see FIG. 6(a)) for driving . . . is generated and supplied to the array driving section 160.

The data input signal Slt is as shown in FIG.
It is shifted at the rising timing of the clock signal CLK, further changed at the falling timing of the latch signal LT, and held at the rising timing, as shown in FIG. 3(C). Then, in synchronization with the arrival of the charged portion of the photoconductor 10 (see (d) in the same figure), the erase array 1 is
50 light emitting elements 152. ...is output.

As a result, as shown in FIG. 7, the data input signal S
In response to the low level of lt, each light emitting element 152 . ..., the light emitting elements B, C, and D are turned off. As a result, light emitting element B.

By turning off the lights C and D, the charge on the photoreceptor 10 is removed leaving a width of 10 mm as the image forming area a.

In this way, the charge is gradually removed by lighting up the light emitting elements other than the light emitting elements B, C, and D line by line in the direction of rotation of the photoreceptor 10, and finally the surface of the photoreceptor 10 is covered with original paper. An image forming area a corresponding to the specified range A on a one-to-one basis is formed.

The portion where the charge has not been removed (image forming area a) is then exposed to light and an electrostatic latent image is formed, and no electrostatic latent image is formed on the other portions.

Therefore, after the copying operation is completed, on the paper P ejected from the copying machine main body 1, only the image corresponding to the specified range A on the document sheet is formed with a width of 10 mm, as shown in FIG. That will happen.

In this way, when performing trimming copying on the same specified range as that during masking, each light emitting element 152 . By controlling the lighting of . . . , the image forming area (charged portion of the photoreceptor) resulting from trimming corresponds to the non-image forming area (charge-eliminating portion of the photoreceptor) during masking.

As mentioned above, in masking copying, which erases the image within a specified range of the original to form an image, and trimming copy, which forms an image only within the specified range of the original, the erased parts of the original and non-images for the specified range are The formation areas are arranged in a one-to-one relationship.

That is, the lighting of the light emitting elements is controlled so that the erased portion of the image in the specified range always matches the non-image forming area from which charges have been removed. As a result, the boundaries between the image forming area and non-image forming area for the same specified range are inconsistent when forming an image by erasing the image within the specified range and when forming an image only within the specified range. This will no longer be the case. Therefore, when forming an image by erasing a part of the document, it is possible to accurately erase the part of the image.

In the above embodiments, an electronic copying machine that can form an image by erasing a part of the original image was used as an example, but the invention is not limited to this. It can also be applied to scanner printers that form images only on the necessary parts by removing them.

It goes without saying that various other modifications can be made without departing from the gist of the invention.

[Effects of the Invention] As described in detail above, according to the present invention, the image quality is different between when forming an image by erasing an image within the same specified range and when forming an image only within the specified range. It is possible to provide an image forming apparatus that can match the boundaries between a forming area and a non-image forming area and can accurately perform partial erasure of an image.

[Brief explanation of the drawing]

Figures 1 to 14 are for explaining one embodiment of the present invention. Figure 1 is a block diagram of the main parts showing the control system, and Figure 2 is an example of a manuscript for explaining the operation. The figure shown,
3 is a timing chart shown to explain the control of the erase array during masking copying, FIG. 4 is a timing chart shown to explain the operation during masking copying, and FIG. 5 is a timing chart shown to explain the operation during masking copying.
The figure shows an example of image formation by masking copy, FIG. 6 is a timing chart shown to explain the control of the erasing array during trimming copy, and FIG. 7 is a diagram shown to explain the operation during trimming copy. , FIG. 8 is a diagram showing an example of image formation by trimming copy, and FIG.
The figure is a side sectional view showing the schematic configuration of an electronic copying machine.
The figure is a plan view showing an example of the operation panel, FIG. 11 is a plan view shown to explain the operation of setting a specified range of a document using the operation panel, and FIG. 12 is a side cross-section of the main part showing the arrangement of the erasing array. 13 is a front view showing the relationship between the erasing array and the photoreceptor, FIG. 14 is a circuit diagram schematically showing the configuration of the array drive section, and FIGS. 15 and 16 are conventional techniques and their problems. FIG. 15 is a diagram for explaining the operation during masking copying, and FIG. 16 is a diagram for explaining the operation during trimming copying. 1...Copying machine main body, 2...Document transport device, 3...Direction conversion transport device, 5...
Document table, 10...Photoreceptor, 11...Charging device, 12...Exposure optical system, 13...
...Developer, 14...Transfer charger, 22.
... Fuser, 50 ... Operation panel, 51
...Copy key, 52...Numeric keypad, 5
3... Display section, 55... Editorial department, 55
a...Select key, 81...Control unit, 150...Erase array, 152...
Light emitting element, 160... Array drive unit, D...
...Manuscript, A, ...Specified range. Applicant's Representative Patent Attorney Takehiko Suzue Figure 1 A Figure 2 Figure 7 Figure 8 Figure 11 Figure 12 Figure 15

Claims (1)

[Claims] A plurality of light emitters are provided, and a portion of the charge applied to the surface of the image carrier is removed by irradiating light from an erasing means in which light from adjacent light emitters is superimposed. This enables the first image forming operation to form an image by erasing the image within the specified range in the original image, and the second image forming operation to form only the image within the specified range in the original image. In the forming apparatus, during the first image forming operation, a light emitting body provided corresponding to the inside of the specified range is turned on, and during the above second image forming operation, the light emitting body provided corresponding to the outside of the specified range is turned on. A control means is provided to turn on the image forming area and the non-image forming area depending on whether the first image forming operation is performed or the second image forming operation is performed on the same specified range. An image forming apparatus characterized in that lighting of the light emitting body is controlled so as to match a boundary with a region.