JP2002225345A - Imaging apparatus and imaging method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an imaging apparatus and an imaging method in which the width of an image being formed on a photosensitive body with high image quality by projecting a laser beam can be enlarged while satisfying the requirements of low cost and small size by coupling images projected onto the photosensitive body with high accuracy using a plurality of laser arrays of small dimensions. SOLUTION: A photosensitive drum 14 is irradiated with a plurality of linear light sources arranged further linearly such that the quantity of light can be controlled for each spot light source to form one main scanning line. Inclining direction and position of a spot light source projected from the linear light source is then adjusted and the line direction and position of each linear light source are altered. Subsequently, the linearity and continuity of a line projected from each of the plurality of linear light sources are regulated based on a predetermined regulation amount and an image is formed by sub-scanning the photosensitive drum 14 with one main scanning line.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus and an image forming method, and more particularly to an image forming apparatus and an image forming method in which an image in a main scanning direction irradiated on a photosensitive member is emitted from at least two or more laser arrays. The present invention relates to an image forming apparatus and an image forming method in which each image is divided into respective images irradiated on the photoconductor corresponding to a beam group, and the respective images are formed to form the image on the photoconductor.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus for forming an image using a laser beam, a laser beam emitted from a laser array is reflected on a polygon mirror rotating at high speed, and reflected on the polygon mirror. An image is formed by irradiating the laser beam onto the photoreceptor to form an image.

On the other hand, Japanese Patent Application Laid-Open No. Hei 9-200431 discloses that a laser beam emitted from a regularly arrayed two-dimensionally arranged laser array is irradiated onto a photoreceptor by an enlarged projection optical system to form an image. A technique for forming an image on the photoconductor by the above-described method (hereinafter, referred to as prior art) is described.

However, when an image is formed on a photoreceptor by using the above-mentioned prior art, a laser beam emitted from a regularly two-dimensionally arrayed laser array is adjusted to a beam diameter required for image formation. It is necessary to collect light and irradiate it on the photoconductor. The number of laser spots irradiated on the photoreceptor is the number of laser spots corresponding to the required image quality, for example, about 14,400 laser spots on the photoreceptor in the case of high image quality of 1200 dpi in A3 size. Laser spots are required. Assuming that the optical magnification for irradiating the laser beam onto the photosensitive member is 6, the width of the laser array in the main scanning direction needs to be about 50 mm.

The width of the laser array in the main scanning direction is about 50 m.
In order to make m, it is necessary to consider the precision of the semiconductor fabrication technology used when creating a laser array, and the yield of non-defective products is greatly affected by the dimensions of the substrate. The method of irradiating the photoreceptor with the system increases the manufacturing cost of the laser array.

For this reason, from the viewpoint of the manufacturing cost of the laser array, the width of the laser array in the main scanning direction must be smaller than about 50 mm, and the image width of irradiating the laser beam on the photosensitive member is limited. It is high quality,
Moreover, it is difficult to realize an image forming apparatus having a large image width for irradiating a laser beam onto a photosensitive member.

On the other hand, image forming apparatuses such as printers are required to be reduced in size, especially thinned, in order to reduce costs and save space.

When a large-sized laser array is applied to an image forming apparatus, a large-diameter projection lens corresponding to the large-sized laser array is required, and the size of the image forming apparatus is further increased. It is difficult to reduce the size or thickness of the image forming apparatus.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and uses a plurality of small-sized laser arrays to combine images irradiated on a photoreceptor with high precision. While meeting the demands for cost reduction and miniaturization,
It is an object of the present invention to provide an image forming apparatus and an image forming method capable of increasing the image width of irradiating a laser beam onto a photoreceptor with high image quality.

[0010]

According to a first aspect of the present invention, there are provided a plurality of point light sources arranged in a dot pattern and an image forming optical system for forming an image of each point light source on an image carrier. A plurality of linear light sources capable of controlling the amount of light for each light source, and a plurality of linear light sources, which are further arranged linearly, and irradiate the image carrier to form a line for one main scan. Scanning means, sub-scanning means for sub-scanning the line for one main scan on the image carrier, line direction position changing means for changing the line direction position of each of the line light sources, and the line light source A tilt direction position changing means for adjusting a tilt direction position of a point light source emitted from the light source, and controlling the line direction position changing means and the tilt direction position changing means on the basis of a predetermined adjustment amount; From each of the linear light sources It is characterized by having a control means for adjusting the linearity and continuity of that line, the.

According to the first aspect of the present invention, a plurality of linear light sources, each of which is capable of controlling the amount of light for each point light source, are further arranged in a line, and are illuminated on the image carrier, and are irradiated for one main scan. Forming a line, adjusting the tilt direction position of the point light source emitted from the linear light source, changing the line direction position of each of the linear light sources, based on a predetermined adjustment amount, The cost is reduced by adjusting the linearity and continuity of the lines emitted from each of the plurality of linear light sources and sub-scanning the one main scanning line on the image carrier to form an image. And while meeting the demand for miniaturization,
It is possible to increase the image width of a high-quality image irradiated with the laser beam on the photosensitive member.

According to a second aspect of the present invention, in the first aspect of the present invention, the line direction position changing means includes:
At least one of the linear light source and the imaging optical system is relatively moved in a normal direction of the linear light source.

According to the second aspect of the present invention, the position in the line direction is changed so that at least one of the linear light source and the image forming optical system is relatively moved in the normal direction of the linear light source. Thus, the laser beam irradiated on the photoconductor can be expanded and contracted in the main scanning direction to combine the images formed by the laser beams emitted from the respective laser arrays on the photoconductor, thereby reducing the cost. It is possible to increase the width of an image to be irradiated with a laser beam onto a photoreceptor with high image quality while satisfying demands for downsizing and downsizing.

According to a third aspect of the present invention, in the first aspect of the present invention, the line direction position changing means comprises:
At least one of the linear light source and the image forming optical system is relatively moved in a main scanning direction in a line direction position of the linear light source.

According to the third aspect of the present invention, at least one of the linear light source and the imaging optical system is moved in the line direction so that the line position of the line light source is relatively moved in the main scanning direction. By making the change in, the laser beam irradiated on the photoconductor is expanded and contracted in the main scanning direction, and each image formed by the laser beam emitted from each laser array on the photoconductor is combined. Accordingly, it is possible to increase the width of an image to be irradiated with a laser beam onto a photoreceptor with high image quality while satisfying demands for cost reduction and miniaturization.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the inclination direction position changing means rotates the linear light source around a normal direction.

According to the fourth aspect of the present invention, the position of the inclination direction is changed so as to rotate the linear light source around the normal direction, so that the linear light source is placed on the main scanning line of the photoconductor. The laser beam irradiating the laser can form an image in a straight line, and while satisfying the demand for cost reduction and miniaturization, it is possible to increase the image quality of irradiating the laser beam onto the photoreceptor with high image quality. it can.

According to a fifth aspect of the present invention, in the first to fourth aspects of the present invention, the control means controls the linearity of the linear light source emitted from each of the plurality of linear light sources. And adjusting the continuity such that the light quantity of each point light source in a boundary region between adjacent linear light sources among the plurality of linear light sources is controlled to be substantially equal to the light amount outside the boundary region.

According to the fifth aspect of the invention, the linearity and continuity of each of the plurality of linear light sources emitted from each of the plurality of linear light sources are adjusted to the adjacent one of the plurality of linear light sources. By controlling the amount of light of each point light source in the boundary region between the linear light sources to be substantially equal to the outside of the boundary region, it is possible to prevent unevenness or image omission in an image formed on the photoconductor, It is possible to increase the image width of a high-quality and irradiating a laser beam onto a photoreceptor while satisfying demands for cost reduction and miniaturization.

According to a sixth aspect of the present invention, there are provided a plurality of point light sources arranged in a point shape and an image forming optical system for forming an image of each point light source on an image carrier. By arranging a plurality of possible linear light sources further linearly and irradiating the image carrier, a line for one main scan is formed, and the inclination direction of the point light source emitted from the linear light source Adjusting the position, changing the line direction position of each of the linear light sources, and adjusting the linearity and continuity of the lines emitted from each of the plurality of linear light sources based on a predetermined adjustment amount. In addition, an image is formed by sub-scanning the line for one main scan on the image carrier.

According to the sixth aspect of the present invention, there are provided a plurality of point light sources arranged in a point shape and an image forming optical system for forming an image of each point light source on an image carrier. A plurality of linear light sources that can be controlled, and the plurality of linear light sources are further arranged in a line, and are illuminated on the image carrier, thereby
Main scanning means for forming a line for main scanning, sub-scanning means for sub-scanning the line for one main scanning on the image carrier, and a line direction for changing a line direction position of each linear light source Position changing means, a tilt direction position changing means for adjusting the tilt direction position of the point light source emitted from the linear light source, based on a predetermined adjustment amount,
A control unit that controls the line direction position changing unit and the tilt direction position changing unit, and adjusts linearity and continuity of lines emitted from each of the plurality of linear light sources. It is possible to prevent unevenness or image omission in an image formed thereon, and to increase the width of an image to be irradiated with a laser beam onto a photoreceptor with high image quality while satisfying requirements for cost reduction and size reduction. .

According to a seventh aspect of the present invention, in the sixth aspect of the present invention, the change of the line direction position includes at least one of the linear light source and the imaging optical system.
The linear light source is relatively moved in a normal direction.

According to the present invention, at least one of the linear light source and the image forming optical system has a line direction position changing means for relatively moving in a normal direction of the linear light source. The image formed on the photoreceptor can be formed with high image quality while irradiating a laser beam onto the photoreceptor while preventing unevenness or image omission of an image formed on the photoreceptor and satisfying requirements for cost reduction and miniaturization. Can be.

According to an eighth aspect of the present invention, in the invention of the sixth aspect, the change of the position in the line direction causes at least one of the linear light source and the image forming optical system to be connected to the linear light source. It is characterized in that the position in the line direction is relatively moved in the main scanning direction.

According to an eighth aspect of the present invention, at least one of the linear light source and the imaging optical system is a line direction position changing means for relatively moving the line direction position of the linear light source in the main scanning direction. By having, the image formed on the photoreceptor can prevent unevenness and image omission, and can satisfy the demand for cost reduction and miniaturization, while achieving high image quality and irradiating the laser beam onto the photoreceptor. The width can be increased.

According to a ninth aspect of the present invention, in the invention of the sixth aspect, the change of the tilt direction position rotates the linear light source around a normal direction.

According to the ninth aspect of the present invention, the image forming apparatus has the inclination direction position changing means for rotating the linear light source around the normal direction. Can be prevented, and the image width of irradiating the laser beam onto the photosensitive member with high image quality can be increased while satisfying the demand for cost reduction and miniaturization.

[0028] The invention according to claim 10 is the invention according to claim 6.
10. The linear light source according to claim 9, wherein linearity and continuity of the linear light sources emitted from each of the plurality of linear light sources are adjusted. It is characterized in that the light quantity of each point light source in the boundary region between the two is adjusted so as to be substantially equal to that outside the boundary region.

According to the tenth aspect of the present invention, the linearity and continuity of each of the plurality of linear light sources emitted from each of the plurality of linear light sources are adjusted to the adjacent one of the plurality of linear light sources. By having control means for controlling the amount of light of each point light source in the boundary region between the linear light sources so as to be substantially equal to the outside of the boundary region, it is possible to prevent unevenness or image omission in an image formed on the photoconductor. Accordingly, it is possible to increase the width of an image to be irradiated with a laser beam onto a photoreceptor with high image quality while satisfying demands for cost reduction and miniaturization.

[0030]

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

FIG. 1 schematically shows an image forming apparatus P according to an embodiment of the present invention.

In the present embodiment, the main scanning direction is the X-axis direction, the sub-scanning direction is the Y-axis direction, and the normal direction of the light emitting surface of the laser array is the Z-axis direction. It will be described using FIG.

The "normal line" in this embodiment is the optical axis of the laser beam emitted from the light source located at the center of the surface of the semiconductor laser array where the light sources are arranged.

The image forming apparatus P includes the semiconductor laser array 1
0a and 10b, magnifying projection lenses 12a and 12b having an object-side telecentric configuration, and a photosensitive drum 14
And

The semiconductor laser arrays 10a and 10b
The laser beams 15a and 15b emitted from the laser beam become laser beams 16a and 16b enlarged and projected by the enlargement projection lenses 12a and 12b, respectively, and are irradiated onto the photosensitive drum 14.

The laser beams 16a and 16b are irradiated on the photosensitive drum 14 and
By forming a line thereon, the main scanning line 20 is formed.

Further, the image forming apparatus P includes semiconductor laser arrays 10a and 10b, an enlarged projection lens 12a,
And position adjustment devices 18a and 18b for adjusting the position and rotation of the first and second positions.

FIG. 2 is a top view when the image forming apparatus P is viewed from the positive direction of the Y axis.

In this embodiment, the image width on the photosensitive drum 14 is set to 150 mm, and the distance from the magnifying projection lens 12b to the photosensitive drum 14 is set to 350 mm.

The position adjusting devices 18a and 18b include a semiconductor laser array 10a and an enlarged projection lens 12a, and a semiconductor laser array 10b and an enlarged projection lens 12b.
Can be moved in the Z-axis direction to adjust the position.

Here, the semiconductor laser array 10b after the position adjusting device 18b has been moved in the Z-axis direction,
Magnifying projection lens 12b, laser beams 15b, 16b,
The position of the position adjusting device 18b is indicated by a two-dot chain line.

Here, the position adjusting devices 18a and 18
b, the semiconductor laser arrays 10a and 10b
When the defocusing of the enlarged projection lenses 12a and 12b in the Z-axis direction is performed by 0.1 mm, the end of the laser beam 16b expands and contracts by about 10 μm on the photosensitive drum 14 in the X-axis direction. Is the laser beam 16
b, the change in the magnification (the change in the lateral magnification) of the line formed on the photosensitive drum 14 in the X-axis direction is 0.0.
Since it is 15%, the effect on the image quality is so small that it can be ignored.

As shown in FIG. 3, the position adjusting devices 18a and 18b are provided with a semiconductor laser array 10a.
And magnifying projection lens 12a, semiconductor laser array 10b
And the magnifying projection lens 12b can be integrally moved to adjust the position by moving in the X-axis direction. here,
The semiconductor laser array 10b, the magnifying projection lens 12b after the position adjusting device 18b has been moved in the Z-axis direction,
Laser beams 15b, 16b and position adjusting device 18b
Is indicated by a two-dot chain line.

FIG. 4 shows laser beams 16a and 16b.
20a irradiated on the photosensitive drum 14 by the
And 20b are not coupled in a straight line.

The position adjusting devices 18a and 18b
The rotation can be adjusted by rotating around the axial direction as the center of rotation.

Accordingly, even when the lines 20a and 20b irradiated on the photosensitive drum 14 by the laser beams 16a and 16b are not coupled to the main scanning line 20 on the photosensitive drum 14, The line 20a and the line 20b can be combined on the main scanning line 20.

In general, a high-quality image requires a resolution of 1200 dpi or more.
The distance between the laser beams on 4 is about 20 μm.
Accordingly, when the image forming apparatus P is assembled without adjusting the positional relationship among the semiconductor laser arrays 10a and 10b, the magnifying projection lenses 12a and 12b, and the photosensitive drum 14, as shown in FIG. , Laser beam 1
In a boundary region between 6a and 16b, a mutual position error of 10 μm at maximum occurs.

In a state where the mutual position error occurs,
When the laser beams 16a and 16b are irradiated on the photoreceptor drum 14 and the lines 20a and 20b are formed, image defects such as stripes or the like occur due to missing images or overlapping images in the X-axis direction. Therefore, a high-quality image cannot be obtained.

Therefore, the position adjusting devices 18a and 18
By performing position adjustment and rotation adjustment of the semiconductor laser arrays 10a and 10b and the magnifying projection lenses 12a and 12b, the image quality defect can be eliminated.

Here, the semiconductor laser array 10
a and the magnifying projection lens 12a and the semiconductor laser array 1
0b and the magnifying projection lens 12b, and using the position adjusting devices 18a and 18b, the photosensitive drum 1
The configuration is such that the positional relationship between the laser beams 16a and 16b irradiated onto the laser beam 4 is adjusted. However, the present invention is not limited to this.
(10b) only or the magnifying projection lens 12a (12
A configuration in which only b) is adjusted may be adopted.

In the image forming apparatus P, the position adjusting devices 18a and 18b are provided with the semiconductor laser arrays 10a and 10a.
0b, and the magnifying projection lenses 12a and 12b may be capable of position adjustment and rotation adjustment independently of each other.

Further, the semiconductor laser array 10a and the magnifying projection lens 12a are integrated, and the semiconductor laser array 10b and the magnifying projection lens 12b are integrated.
And the semiconductor laser array 10b and the magnifying projection lens 12b may be adjusted together by the position adjusting device 18b.

FIG. 6 is a functional block diagram for controlling the image forming apparatus P.

The image forming apparatus P includes a photosensitive drum 1
4 is connected.

The drum driving device 100 is provided with a drum rotation control circuit 102 for outputting a timing signal synchronized with the rotation of the photosensitive drum 14.

The image forming apparatus P has an image memory 10 for storing image data for forming an image.
4 are provided.

A signal processing circuit 106 is connected to the image memory 104.

The signal processing circuit 106 is connected to a first laser drive circuit 108a for driving the semiconductor laser array 10a and a second laser drive circuit 108b for driving the semiconductor laser array 10b.

As a result, the signal processing circuit 106
The image data stored in the image memory 104 is read, and the image data is processed based on a timing signal output from the drum rotation control circuit 102 to output a recording signal according to a recording pattern. When the recording signal output from the signal processing circuit 106 is input to the first laser driving circuit 108a and the second laser driving circuit 108b, the first laser driving circuit 108a and the second laser driving circuit 108b are independently driven by the semiconductor laser array. 10
a and 10b can be driven.

Further, the laser beam 16a and the laser beam 16a irradiated on the photosensitive drum 14 are applied to the image forming apparatus P.
A detection device 110 for detecting the position of 6b is provided.

A control circuit 11 for storing the positions of the laser beams 16a and 16b and outputting data on image switching positions when forming the lines 20a and 20b in the signal processing circuit 106 is provided in the detection device 110.
2 are connected.

The magnifying projection lenses 12a and 12a
b to irradiate the photosensitive drum 14 with the laser beam 16
a and 16b substantially coincide with each other near the center of the photosensitive drum 14 in the X-axis direction, or the laser beam 1
The positional relationship between the semiconductor laser arrays 10a and 10b and the magnifying projection lenses 12a and 12b is set such that the boundary region between the laser beam 6a and the laser beam 16b overlaps.
Thus, by adjusting the positional relationship using the position adjusting devices 18a and 18b, the line 20a and the line 20b irradiated on the photosensitive drum 14 can be coupled with high accuracy (described later). ).

In adjusting the positional relationship, in order to detect the position of the laser beam irradiated on the photosensitive drum 14, a light position detector such as a CCD is used instead of the photosensitive drum 14. A detection device 110 for detecting the positions of the laser beams 16a and 16b is arranged at the position of the photosensitive drum 14. As a result, the positions of the laser beams 16a and 16b irradiated on the photosensitive drum 14 are stored in the control circuit 112, and the image switching position when the lines 20a and 20b are formed in the signal processing circuit 106. Is output, and the position adjusting device 18 is output.
By driving a and 18b, the positional relationship can be adjusted.

In the image forming apparatus P, an image forming apparatus such as a charger, a developing machine, and a transfer machine (not shown) is provided around the photosensitive drum 14.

The transfer unit (not shown) supplies a recording sheet to the transfer unit, a fixing unit for fixing the toner image transferred to the recording sheet, and discharges the recording sheet on which the toner image is fixed. A paper discharge unit is provided.

FIG. 7 is a perspective view of the semiconductor laser arrays 10a and 10b.

The semiconductor laser array 10a and the semiconductor laser array 10b have the same configuration.

The light emitting portions 10s of the laser array are two-dimensionally arranged on the light emitting surfaces of the semiconductor laser arrays 10a and 10b, and the timing signal output from the drum rotation control circuit 102 and the recording signal output from the signal processing circuit 106 The first laser drive circuit 108a and the second laser drive circuit 108b operate in response to
a and 15b are emitted.

Laser beams 16a and 16b, which are laser beams obtained by enlarging and projecting laser beams 15a and 15b by using expansion projection lenses 12a and 12b, respectively.
Are irradiated on the photosensitive drum 14 to form lines 20a and 20b in the X-axis direction. The lines 20a and 20b are combined on the main scanning line 20 to form a row of electrostatic latent images. When one row of the electrostatic latent images is formed, the photosensitive drum 14 rotates. Thereby, the photosensitive drum 14
, An electrostatic latent image is also formed in the sub-scanning direction, and a two-dimensional electrostatic latent image is sequentially formed on the photosensitive drum 14.

The two-dimensional electrostatic latent image formed on the photosensitive drum 14 is developed with toner by a developing machine.
The toner image formed by the toner development is transferred to a recording sheet fed from a sheet feeding unit by a transfer machine. The image transferred to the recording paper by the transfer machine is fixed by a fixing unit, and is discharged by a discharge unit.

Through the above process, a high quality image is formed on the recording paper. In the above-described image formation, the lines 20a and 20b correspond to the laser beams 16a and 16a in the X-axis direction.
6b is formed on the photosensitive drum 14 and an image is formed with high precision by connecting the line 20a and the line 20b (described later).

Next, the image forming apparatus P in the present embodiment
The operation of will be described in detail.

The laser beam 15a emitted from the semiconductor laser array 10a enters the magnifying projection lens 12a.

The laser beam 15a is magnified and projected by the magnifying projection lens 12a to become a laser beam 16a, and the laser beam 16a is irradiated onto the photosensitive drum 14.

The laser beam 16a forms a line 20a on the photosensitive drum 14 on the right side in the X-axis direction.

On the other hand, the laser beam 15b emitted from the semiconductor laser array 10b enters the magnifying projection lens 12b.

The laser beam 15b is magnified and projected by the magnifying projection lens 12b to become a laser beam 16b, and the laser beam 16b is irradiated onto the photosensitive drum 14.

The laser beam 16b forms a line 20b on the photosensitive drum 14 on the left side in the X-axis direction.

If the beam position in the boundary area between the laser beams 16a and 16b is not on the main scanning line 20, the semiconductor laser array 10a and the magnifying projection lens 12a, and the semiconductor laser arrays 10b and 12b
And the position adjusting devices 18a and 18b
Thus, the rotation about the Z axis is adjusted (see FIGS. 1 to 4).

The beam position in the boundary area between the laser beam 16a and the laser beam 16b is
If they are aligned above, the semiconductor laser arrays 10a and 10a
0b, the enlarged projection lenses 12a and 12b, and the photoconductor drum 14 have a positional relationship shown in FIG. 5B or 5C.
The laser beam 16a and the laser beam 16b shown in FIG.
And the ends of the laser beams 16a and 16b partially cross over, that is, the ends of the laser beams 16a and 16b overlap. The appropriate positions of the position adjustment devices 18a and 18b are stored and set in the control circuit 112 so as to be in the state of being shifted.

On the other hand, the semiconductor laser arrays 10a and 10a
b, the magnifying projection lenses 12a and 12b, and the photosensitive drum 14 are in the state shown in FIG. 5A, the semiconductor laser array 10b and the magnifying projection lens 1
The end of the laser beam 16b irradiated on the photosensitive drum 14 is expanded and contracted in the X-axis direction by moving the position adjustment device 18b in the Z-axis direction in parallel with the 2b (see FIG. 2). By such adjustment, FIG.
Alternatively, as shown in FIG.
In the boundary region between the laser beam 16a and the laser beam 16b, the beam position in the boundary region between the laser beam 16a and the laser beam 16b is matched at an interval of 20 μm, or the beam position in the boundary region between the laser beam 16a and the laser beam 16b is changed. The lines 20a and 20b formed by the laser beam 16a and the laser beam 16b irradiated on the photosensitive drum 14 can be partially overlapped.

FIG. 8 shows the signal processing circuit 106 to the first laser driving circuit 108a and the second laser driving circuit 108b.
The drive signal input to the control circuit is shown.

FIG. 8A shows the state shown in FIG.
When the beam position of the boundary region between the laser beam 16a and the laser beam 16b is adjusted so as not to overlap,
Drive signal 1 input from the signal processing circuit 106 to the first laser drive circuit 108a and the second laser drive circuit 108b
14a and 114b are shown.

The laser beam 16 is positioned so that the beam positions in the boundary region between the laser beam 16a and the laser beam 16b shown in FIG.
When adjusting the linearity and continuity between the laser beam 16a and the laser beam 16b, the lines 20a and 20b on the photosensitive drum 14 are aligned with the laser beam 16a and the laser beam 1b.
6b. At this time, like the driving signals 114a and 110b shown in FIG. 8A, the switching point of the line on which the laser beam 16a and the laser beam 16b are irradiated on the photosensitive drum 14 in the X-axis direction is set. The signal processing circuit 106 generates the boundary driving signal based on the data in the image memory 104.

FIG. 8B shows a state where the beam positions in the boundary region between the laser beam 16a and the laser beam 16b shown in FIG. 5C are matched, and the laser beams 16a and 16b Drive signals 114a and 114b input from the signal processing circuit 106 to the first laser drive circuit 108a and the second laser drive circuit 108b when the positions are adjusted so as to overlap each other are shown.

The beam positions in the boundary area between the laser beams 16a and 16b shown in FIG.
When adjusting the linearity and continuity of the laser beam 16a and the laser beam 16b so that the laser beam 16a and the laser beam 16b overlap by a predetermined number,
The main scanning line 20 is formed by combining the line 20a and the line 20b irradiated on the photosensitive drum 14 in the X-axis direction so as not to deteriorate the image quality.

Therefore, as shown in FIG. 8B, in the boundary region where the end of the laser beam 16a and the laser beam 16b cross over, the pulse width of the drive signals 114a and 114b, the current value or When the light amounts of the laser beams 15a and 15b are determined in proportion to the voltage value, the pulse widths of the drive signals 114a and 114b in the boundary area and the drive signals 114a and 114b
The drive signals 114a and 114b are generated so that the sum of the current value or the voltage value of the reference 4b is constant, and the light amount of each point light source in the crossover boundary area is substantially equal to the outside of the boundary area. Adjust to

In this embodiment, the semiconductor laser array 1
0b and the magnifying projection lens 12b are integrated, and the positional relationship between the laser beams 16a and 16b irradiated on the photosensitive drum 14 is adjusted using the position adjusting device 18b. The device 18b (18
The same effect can be obtained by adjusting only the semiconductor laser array 10b (10a) or only the magnifying projection lens 12b (12a).

The semiconductor laser array 10b and the magnifying projection lens 12b are integrated, and the semiconductor laser array 10a and the magnifying projection lens 12a are integrated. The same effect can be obtained even if the position adjusting device 18b adjusts the laser array 10b and the magnifying projection lens 12b together.

In the image forming apparatus and the image forming method according to the present embodiment, the lines 20 a and 20 b formed by the laser beams 16 a and 16 b are irradiated on the main scanning line 20, and the laser beams are aligned on the photosensitive drum 14 in a straight line. Since the ends of the beams 16a and 16b are combined, image quality does not deteriorate.

In the image forming apparatus according to the present embodiment,
The main scanning line 20 irradiated on the photosensitive drum 14 is divided into two lines 20a and 20b in the X-axis direction, and the line 20a and the line 20b are combined with high precision to form one main scanning line 20. This prevents the image quality from deteriorating on the photosensitive drum 14. However, the number of divisions of the main scanning line 20 is not limited to this, and the main scanning line 20 is divided into at least two or more lines to correspond to the number of the at least two or more lines. By providing a number of semiconductor laser arrays, a magnifying projection lens, a position adjusting device, a laser driving circuit, and the like, an image forming apparatus and an image forming method capable of forming an image with a desired image width with high accuracy can be realized.

[0092]

As described above, the present invention divides a main scanning line irradiated on a photoreceptor into at least two or more lines, and provides a semiconductor laser array corresponding to the number of divided lines. , The entire image is formed with a desired image width with high accuracy without causing image quality defects such as streaks due to missing images or overlapping images by providing an enlargement projection lens, an adjusting unit, a laser driving circuit, and the like. .

Further, since the image width can be increased without using a large-sized laser array and an enlarged projection lens having a large aperture, the image forming apparatus can be reduced in cost and size.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 illustrates an image forming apparatus according to an embodiment of the present invention.
It is the top view seen from the axial positive direction.

FIG. 3 shows an image forming apparatus according to an embodiment of the present invention.
It is the top view seen from the axial direction.

FIG. 4 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention.

5A is a diagram in which a mutual position error occurs in a boundary region between laser beams emitted from each laser array, and FIG. 5B is a diagram in which the beam positions of the laser beam boundary region do not overlap. (C) is a diagram in which the beam positions in the boundary region between the laser beams emitted from the respective laser beams are made to coincide with each other, and the laser beams are adjusted so as to overlap by a predetermined number.

FIG. 6 is a functional block diagram of the image forming apparatus according to the embodiment of the present invention.

FIG. 7 is a perspective view of a semiconductor laser array according to an embodiment of the present invention.

FIG. 8A is a driving signal input to a first laser driving circuit and a second laser driving circuit when beam positions do not overlap in a boundary region of a laser beam;
(B) is a drive signal input to the first laser drive circuit and the second laser drive circuit when the beam positions coincide in the boundary region of the laser beam.

[Explanation of symbols]

10a, 10b Semiconductor laser array 12a, 12b Magnifying projection lens 14 Photoconductor drum 15a, 15b Laser beam 16a, 16b Laser beam 18a, 18b Position adjustment device 20 Main scanning line 20a, 20b Laser beam train irradiated on photoconductor drum REFERENCE SIGNS LIST 100 drum driving device 102 drum rotation driving circuit 104 image memory 106 signal processing circuit 108 a first laser driving circuit 108 b second laser driving circuit 110 detecting device 112 control circuit 114 a, 114 b driving signal

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 1/23 103 H04N 1/04 104Z 5F073 F term (Reference) 2C362 AA13 AA14 AA16 AA17 AA42 AA45 AA47 AA48 AA54 AA63 BA49 BA71 BA84 BB28 BB46 2H076 AB06 AB18 EA24 5C051 AA02 CA07 DA03 DB30 DC02 DE22 DE24 FA01 5C072 AA03 BA01 DA02 DA21 FA05 FA07 FB03 FB06 XA01 XA05 5C074 AA10 AA11 BB03 CC26 DD15 EE04 GG03 GG03 GG03 GG03 GG03 GG03GG

Claims (10)

[Claims] 1. A plurality of linear light sources comprising: a plurality of point light sources arranged in a point-like manner; Main scanning means for arranging the plurality of linear light sources further linearly, and irradiating the light onto the image carrier to form a line for one main scan; Sub-scanning means for sub-scanning on the image carrier; line direction position changing means for changing the line direction position of each of the linear light sources; and adjusting the tilt direction position of the point light sources emitted from the line light sources. Controlling the line direction position changing means and the tilt direction position changing means based on a predetermined adjustment amount, and controlling a straight line of a line emitted from each of the plurality of linear light sources. Adjusts continuity and continuity An image forming apparatus having a control means. 2. An image according to claim 1, wherein said line direction position changing means relatively moves at least one of said line light source and said image forming optical system in a normal direction of said line light source. Forming equipment. 3. The apparatus according to claim 2, wherein said line direction position changing means relatively moves at least one of said line light source and said image forming optical system in a main scanning direction in a line direction position of said line light source. Item 2. The image forming apparatus according to Item 1. 4. The image forming apparatus according to claim 1, wherein the inclination direction position changing unit rotates the linear light source around a normal direction. 5. The control unit according to claim 1, wherein the linearity and the continuity of the linear light sources emitted from the plurality of linear light sources are adjusted between adjacent linear light sources of the plurality of linear light sources. 5. The image forming apparatus according to claim 1, wherein control is performed such that the light amount of each point light source in the boundary region is substantially equal to the light amount outside the boundary region. 6. A plurality of linear light sources comprising a plurality of point light sources arranged in a point shape and an image forming optical system for forming an image of each point light source on an image carrier, wherein a plurality of linear light sources can be controlled in light amount for each point light source. Are further linearly arranged, and by irradiating the image carrier, a line for one main scan is formed, and a tilt direction position of a point light source emitted from the linear light source is adjusted. The linear direction position of the linear light source is changed, and the linearity and continuity of the line emitted from each of the plurality of linear light sources are adjusted based on a predetermined adjustment amount. Line is sub-scanned on the image carrier,
An image forming method comprising forming an image. 7. The apparatus according to claim 6, wherein the change of the position in the line direction is to move at least one of the linear light source and the imaging optical system in a normal direction of the linear light source. The image forming method as described in the above. 8. The method according to claim 1, wherein the change in the line direction position is to move at least one of the line light source and the imaging optical system relative to the line direction position of the line light source in the main scanning direction. The image forming method according to claim 6, wherein 9. The image forming method according to claim 6, wherein the change of the tilt direction position is to rotate the linear light source around a normal direction. 10. Adjustment of the linearity and continuity of each of the plurality of linear light sources emitted from each of the plurality of linear light sources is performed in each of the boundary regions between adjacent linear light sources among the plurality of linear light sources. The image forming method according to claim 6, wherein the light amount of the point light source is adjusted to be substantially equal to the outside of the boundary area.