A method for reducing image density deviation in a laser scanning device

Abstract

The present invention provides a method for reducing image density deviation in a laser scanning device, comprising the following steps: Step S101, irradiating the surface of an OPC photosensitive drum with laser light generated by a laser diode after processing by an optical component; Step S102, collecting first light intensity information along the main scanning direction of the OPC photosensitive drum surface; Step S103, performing deviation correction processing on the first light intensity information by adjusting the light intensity of the laser diode to generate second light intensity information along the main scanning direction of the OPC photosensitive drum surface; and obtaining the image density of the laser scanning device based on the second light intensity information. A technical effect of the present invention is that it has an excellent design and can effectively reduce image density deviation, thereby ensuring the print quality of the laser printer.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical devices, and in particular relates to a method for reducing image concentration deviation in a laser scanning device. Background Art

[0002] The laser scanning device, a core component within a laser printer, consists of a light-emitting diode (LD), a coupling lens, a polygonal mirror motor, soundproof glass, an Fθ lens, a reflector, and an OPC drum. The laser scanning device operates as follows: First, the digital signal to be printed is converted into LD laser light by the LED; then, the coupling lens forms the LD laser into a parallel beam; then, this parallel beam reaches the high-speed rotating polygonal mirror motor and, after being reflected by its mirror surface, passes through the soundproof glass, Fθ lens, and reflector, irradiating the rotating OPC drum, forming an electrostatic latent image.

[0003] In the current laser printer operation, the parallel light beam formed by the LD laser needs to pass through the mirror surface of the polygonal mirror motor, and then pass through the soundproof glass, Fθ lens and reflector in sequence. Along the main scanning direction, the incident angle of the light after being reflected by the polygonal mirror motor is different, resulting in different transmittances of the soundproof glass and reflectances of the reflector, which in turn causes deviations in the amount of light reaching the surface of the OPC photosensitive drum.

[0004] Therefore, the printed image will have uneven density in the main scanning direction, such as Figure 4 shown. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art and provide a new technical solution for a method of reducing image concentration deviation in a laser scanning device.

[0006] According to one aspect of the present invention, a method for reducing image density deviation in a laser scanning device is provided, comprising the following steps:

[0007] Step S101: laser light generated by a laser diode is processed by an optical component and then irradiated onto the surface of an OPC photosensitive drum.

[0008] Step S102, collecting first light intensity information of the OPC photosensitive drum surface along the main scanning direction;

[0009] Step S103, performing deviation correction processing on the first light intensity information by adjusting the light intensity of the laser diode to form second light intensity information of the OPC photosensitive drum surface along the main scanning direction; obtaining the image density of the laser scanning device according to the second light intensity information.

[0010] Optionally, the luminous intensity includes luminous power and luminous time.

[0011] Optionally, the optical components include a polygonal mirror motor, soundproof glass, an Fθ lens and a reflector. The laser generated by the laser diode can pass through the mirror of the polygonal mirror motor and the output light passes through the soundproof glass, the Fθ lens and the reflector in sequence to irradiate the surface of the OPC photosensitive drum; wherein, the polygonal mirror motor is used to receive light and reflect it through mirror rotation to form a scanning beam; the soundproof glass is used to isolate the noise of the motor, and the Fθ lens is used to convert light scanned at equal angles into light scanned at equal speeds; the reflector is used to reflect light, and multiple reflectors can be provided in the laser scanning device to achieve reflection of light.

[0012] Optionally, the optical components also include a coupling lens, a grating and a cylindrical focusing lens, and the laser generated by the laser diode passes through the coupling lens, the grating and the cylindrical focusing lens in sequence to irradiate the mirror surface of the polygonal motor; the coupling lens is used to focus the light for the first time; the grating is used to block part of the light; and the cylindrical focusing lens is used to focus the light for the second time.

[0013] Optionally, the first light intensity information includes a first area, a second area and a third area; the first area and the third area are symmetrically arranged along the center line of the second area, and the light intensity of the first area and the third area is less than the light intensity of the second light intensity information.

[0014] Optionally, performing deviation correction processing on the first light intensity information by adjusting the light emitting power and light emitting time of the laser diode includes:

[0015] The light intensity of the first area and the third area of ​​the first light intensity information is increased by adjusting the light emitting power and the light emitting time of the laser diode, and the light intensity of the second area of ​​the first light intensity information is reduced.

[0016] Optionally, the luminous intensity has multiple parts along the main scanning direction, and the luminous intensity of the multiple parts is different, and the luminous intensity in the middle area is smaller than the luminous intensity in the edge area.

[0017] Optionally, the parts include a first part, a second part, a third part, a fourth part, a fifth part, a sixth part, a seventh part, an eighth part and a ninth part;

[0018] The first portion and the ninth portion are symmetrically arranged along the center line of the fifth portion; the second portion and the eighth portion are symmetrically arranged along the center line of the fifth portion; the third portion and the seventh portion are symmetrically arranged along the center line of the fifth portion; and the fourth portion and the sixth portion are symmetrically arranged along the center line of the fifth portion.

[0019] The luminous intensity of the first part, the second part, the third part, the fourth part and the fifth part decreases in sequence;

[0020] The luminous intensities of the fifth portion, the sixth portion, the seventh portion, the eighth portion, and the ninth portion increase in sequence.

[0021] Optionally, the luminous intensity of the first part is the same as the luminous intensity of the ninth part; the luminous intensity of the second part is the same as the luminous intensity of the eighth part; the luminous intensity of the third part is the same as the luminous intensity of the seventh part; and the luminous intensity of the fourth part is the same as the luminous intensity of the sixth part.

[0022] Optionally, the luminous intensity of the second part is 90% of the luminous intensity of the first part; the luminous intensity of the third part is 76% of the luminous intensity of the first part; the luminous intensity of the fourth part is 70% of the luminous intensity of the first part; and the luminous intensity of the fifth part is 66% of the luminous intensity of the first part.

[0023] A technical effect of the present invention is:

[0024] In the embodiment of the present application, the first light intensity information is processed for deviation correction by adjusting the light intensity of the laser diode to form second light intensity information along the main scanning direction of the OPC photosensitive drum surface. The image density of the laser scanning device is obtained based on the second light intensity information. Because the second light intensity information is generated by performing deviation correction on the first light intensity information by adjusting the light intensity of the laser diode, the density deviation of the second light intensity information along the main scanning direction is relatively small, thereby achieving better consistency in the image density of the laser scanning device, thereby ensuring better print quality of the laser printer. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A flowchart of a method for reducing image density deviation in a laser scanning device according to an embodiment of the present invention;

[0026] Figure 2 Schematic diagram of the structure of the laser scanning device of the present invention;

[0027] Figure 3 Schematic diagram of the propagation of light reflected by the mirror surface of the polygonal mirror motor of the laser scanning device of the present invention;

[0028] Figure 4 is a schematic diagram of first light intensity information in the prior art;

[0029] Figure 5 A schematic diagram of first light intensity information of the laser scanning device of the present invention;

[0030] Figure 6 A schematic diagram showing a comparison of the luminous intensity of the laser diode of the laser scanning device of the present invention along the main scanning direction;

[0031] Figure 7 Schematic diagram of the laser scanning device before and after the luminous intensity correction of the present invention.

[0032] In the figure: 1. Polygonal mirror motor; 2. Soundproof glass; 3. Fθ lens; 4. Reflecting mirror; 5. OPC photosensitive drum; 6. Coupling lens; 7. Grating; 8. Cylindrical focusing lens;

[0033] 100, first area; 200, second area; 300, third area; 91, first part;

[0034] 92. Part 2; 93. Part 3; 94. Part 4; 95. Part 5;

[0035] 96. Part 6; 97. Part 7; 98. Part 8; 99. Part 9;

[0036] 10. Laser diode; 11. Light. DETAILED DESCRIPTION

[0037] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0038] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0039] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly refer to one or more of the features. Throughout the description of this application, unless otherwise specified, "plurality" means two or more. Furthermore, "and / or" in the specification and claims refers to at least one of the connected entities, and the character " / " generally indicates an "or" relationship between the connected entities.

[0040] See also Figures 1 to 7The embodiment of the present application provides a method for reducing image concentration deviation of a laser scanning device, which can effectively reduce the image concentration deviation of the laser scanning device, ensure the consistency of image concentration, and significantly improve the printing quality of the laser printer.

[0041] Specifically, the method for reducing image density deviation in a laser scanning device includes the following steps:

[0042] In step S101 , the laser light generated by the laser diode 10 is irradiated onto the surface of the OPC photosensitive drum 5 after being processed by optical components.

[0043] Step S102: collecting first light intensity information along the main scanning direction of the surface of the OPC photosensitive drum 5. That is, collecting the light intensity information along the main scanning direction of the surface of the OPC photosensitive drum 5 in the prior art.

[0044] Step S103, performing deviation correction processing on the first light intensity information by adjusting the light intensity of the laser diode 10 to form second light intensity information on the surface of the OPC photosensitive drum 5 along the main scanning direction; and obtaining the image density of the laser scanning device according to the second light intensity information.

[0045] In the embodiment of the present application, the first light intensity information is subjected to deviation correction processing by adjusting the light intensity of the laser diode 10 to form second light intensity information on the surface of the OPC photosensitive drum 5 along the main scanning direction. The image density of the laser scanning device is obtained based on the second light intensity information. Because the second light intensity information is formed by performing deviation correction processing on the first light intensity information by adjusting the light intensity of the laser diode 10, the density deviation of the second light intensity information along the main scanning direction is relatively small, thereby achieving better consistency in the image density of the laser scanning device, thereby ensuring better print quality of the laser printer.

[0046] contrast Figure 4 and Figure 5 The method for reducing image concentration deviation for a laser scanning device of the present application can effectively reduce image concentration deviation, better ensure the consistency of image concentration in the main scanning direction, and help improve the printing quality of laser printers.

[0047] It should be noted that a laser printer includes a main scanning direction and a sub-scanning direction. The sub-scanning direction is the direction in which the paper travels, and its perpendicular direction is the main scanning direction, that is, the arrangement direction of the scanning elements.

[0048] Optionally, the luminous intensity includes luminous power and luminous time, which can simply and efficiently adjust the luminous intensity of the laser diode 10 and is very convenient to operate.

[0049] See also Figure 3The optical components include a polygonal motor 1, soundproof glass 2, Fθ lens 3, and reflector 4. The laser light generated by the laser diode 10 is reflected by the mirror surface of the polygonal motor 1. The emitted light passes through the soundproof glass 2, the Fθ lens 3, and the reflector 4 in sequence and irradiates the surface of the OPC photosensitive drum 5. The polygonal motor 1 is used to receive light 11 through mirror rotation and reflect it to form a scanning beam. The soundproof glass 2 is used to block motor noise. The Fθ lens 3 is used to convert the light 11 scanned at equal angles into light scanned at equal speeds. The reflector 4 is used to reflect the light 11. The optical components can propagate the laser light generated by the laser diode 10, ensuring the intensity of the light reaching the surface of the OPC photosensitive drum 5.

[0050] See also Figure 2 The optical components also include a coupling lens 6, a grating 7, and a cylindrical focusing lens 8. The laser light generated by the laser diode 10 sequentially passes through the coupling lens 6, grating 7, and cylindrical focusing lens 8 and is irradiated onto the mirror surface of the polygonal mirror motor 1. The coupling lens 6 is used to perform a primary focusing of the light 11; the grating 7 is used to block a portion of the light 11; and the cylindrical focusing lens 8 is used to perform a secondary focusing of the light 11. This simplifies the propagation of the laser light generated by the laser diode 10 and facilitates optimization of the internal structure of the laser scanning device.

[0051] Optionally, the first light intensity information includes a first region 100, a second region 200, and a third region 300; the first region 100 and the third region 300 are symmetrically arranged along the center line of the second region 200, and the light intensity of the first region 100 and the third region 300 is less than the light intensity of the second light intensity information. The first light intensity information refers to the light intensity information reaching the surface of the OPC photosensitive drum 5 in the prior art. By collecting and analyzing the first light intensity information and performing deviation correction on the first light intensity information, it is helpful to reduce the deviation of the corrected second light intensity information along the main scanning direction, thereby further helping to reduce the deviation of image density in the main scanning direction, thereby significantly improving the print quality of the laser printer.

[0052] Optionally, performing deviation correction processing on the first light intensity information by adjusting the light emitting power and light emitting time of the laser diode 10 includes:

[0053] By adjusting the light power and light time of the laser diode 10 , the light intensity of the first area 100 and the third area 300 of the first light intensity information is increased, and the light intensity of the second area 200 of the first light intensity information is reduced.

[0054] In the above embodiment, by increasing the light intensity of the first area 100 and the third area 300 of the first light intensity information and reducing the light intensity of the second area 200 of the first light intensity information, the deviation of the second light intensity information along the main scanning direction can be effectively reduced, which in turn helps to further reduce the deviation of the image concentration in the main scanning direction, thereby effectively improving the printing quality of the laser printer.

[0055] Optionally, the luminous intensity has multiple parts along the main scanning direction, and the luminous intensity of the multiple parts is different, and the luminous intensity in the middle area is smaller than the luminous intensity in the edge area.

[0056] In the above embodiment, the luminous intensity of the laser diode 10 is increased for the position where the image density is smaller at the edge, while the luminous intensity of the laser diode 10 is increased for the position where the image density is larger in the middle, thereby greatly reducing the image density deviation along the main scanning direction, ensuring that the amount of light reaching the surface of the OPC photosensitive drum 5 along the main scanning direction is consistent, and the image density is consistent in the main scanning direction, thereby providing better printing quality of the laser printer.

[0057] Alternatively, see Figure 6 , the parts include a first part 91, a second part 92, a third part 93, a fourth part 94, a fifth part 95, a sixth part 96, a seventh part 97, an eighth part 98 and a ninth part 99;

[0058] The first portion 91 and the ninth portion 99 are symmetrically arranged along the center line of the fifth portion 95; the second portion 92 and the eighth portion 98 are symmetrically arranged along the center line of the fifth portion 95; the third portion 93 and the seventh portion 97 are symmetrically arranged along the center line of the fifth portion 95; and the fourth portion 94 and the sixth portion 96 are symmetrically arranged along the center line of the fifth portion 95.

[0059] The luminous intensity of the first part 91, the second part 92, the third part 93, the fourth part 94, and the fifth part 95 decreases in sequence;

[0060] The luminous intensities of the fifth portion 95 , the sixth portion 96 , the seventh portion 97 , the eighth portion 98 , and the ninth portion 99 increase in sequence.

[0061] It should be noted that the curve above the arrow line is a schematic diagram of the luminous intensity of the laser diode 10 along the main scanning direction in the prior art; the curve above the arrow line is a schematic diagram of the luminous intensity of the laser diode 10 along the main scanning direction in the present application. The horizontal axis represents time, and the vertical axis represents the high level. The area of ​​each section represents the luminous intensity.

[0062] In the above embodiment, the various parts of the luminous intensity of the laser diode 10 can be specifically adjusted according to the actual situation of the image concentration in the prior art, which helps to ensure the deviation correction effect of the first light intensity information, thereby significantly reducing the concentration deviation of the second light intensity information along the main scanning direction, so that the image concentration of the laser scanning device is more consistent, thereby ensuring better printing quality of the laser printer.

[0063] Optionally, the luminous intensity of the first portion 91 is the same as the luminous intensity of the ninth portion 99; the luminous intensity of the second portion 92 is the same as the luminous intensity of the eighth portion 98; the luminous intensity of the third portion 93 is the same as the luminous intensity of the seventh portion 97; and the luminous intensity of the fourth portion 94 is the same as the luminous intensity of the sixth portion 96. This allows for very accurate adjustment of the luminous intensity of the laser diode 10 at various levels, reducing the difficulty of adjusting the luminous intensity of the laser diode 10 while ensuring accuracy of the adjustment.

[0064] Figure 7 The following figure compares the luminous intensity curve of the laser diode 10 before and after correction. Clearly, the luminous intensity in the center of the laser diode 10 along the main scanning direction decreases in the corrected curve, while the luminous intensity at the edges increases. This effectively compensates for the higher image density in the center and the lower image density at the edges, ensuring image density consistency.

[0065] Optionally, the luminous intensity of the second portion 92 is 90% of the luminous intensity of the first portion 91; the luminous intensity of the third portion 93 is 76% of the luminous intensity of the first portion 91; the luminous intensity of the fourth portion 94 is 70% of the luminous intensity of the first portion 91; and the luminous intensity of the fifth portion 95 is 66% of the luminous intensity of the first portion 91. By limiting the luminous intensity of the laser diode 10 to various portions, the amount of light reaching the surface of the OPC photosensitive drum 5 along the main scanning direction is made uniform, thereby effectively reducing deviations in image density in the main scanning direction and better ensuring the print quality of the laser printer.

[0066] It will be understood that the above embodiments are merely exemplary embodiments for illustrating the principles of the present invention, and the present invention is not limited thereto. Those skilled in the art will appreciate that various modifications and improvements can be made without departing from the spirit and substance of the present invention, and such modifications and improvements are also considered to be within the scope of protection of the present invention.

Claims

1. A method for reducing image density deviation in a laser scanning device, characterized in that: The steps include: Step S101: laser light generated by a laser diode is irradiated onto the surface of an OPC photosensitive drum after being processed by optical components. Step S102, collecting first light intensity information of the OPC photosensitive drum surface along the main scanning direction; Step S103, performing deviation correction processing on the first light intensity information by adjusting the light intensity of the laser diode to form second light intensity information of the OPC photosensitive drum surface along the main scanning direction; obtaining the image density of the laser scanning device based on the second light intensity information; the light intensity includes light power and light time; The first light intensity information includes a first area, a second area, and a third area; the first area and the third area are symmetrically arranged along the center line of the second area, and the light intensity of the first area and the third area is less than the light intensity of the second light intensity information; The deviation correction process is performed on the first light intensity information by adjusting the light emitting power and light emitting time of the laser diode, including: The light intensity of the first area and the third area of ​​the first light intensity information is increased by adjusting the light emitting power and the light emitting time of the laser diode, and the light intensity of the second area of ​​the first light intensity information is reduced.

2. The method for reducing image density deviation in a laser scanning device according to claim 1, wherein: The optical components include a polygonal mirror motor, soundproof glass, an Fθ lens and a reflector. The laser generated by the laser diode can pass through the mirror of the polygonal mirror motor, and the output light passes through the soundproof glass, the Fθ lens and the reflector in sequence to irradiate the surface of the OPC photosensitive drum; wherein, the polygonal mirror motor is used to receive light and reflect it through mirror rotation to form a scanning beam; the soundproof glass is used to isolate the noise of the motor, and the Fθ lens is used to convert the light scanned at equal angles into light scanned at equal speeds; and the reflector is used to reflect the light.

3. The method for reducing image density deviation in a laser scanning device according to claim 2, wherein: The optical components also include a coupling lens, a grating and a cylindrical focusing lens. The laser generated by the laser diode passes through the coupling lens, the grating and the cylindrical focusing lens in sequence and irradiates the mirror surface of the polygonal mirror motor; the coupling lens is used to focus the light for the first time; the grating is used to block part of the light; and the cylindrical focusing lens is used to focus the light for the second time.

4. The method for reducing image density deviation in a laser scanning device according to claim 3, wherein: The luminous intensity has multiple parts along the main scanning direction, and the luminous intensity of the multiple parts is different. The luminous intensity in the middle area is smaller than the luminous intensity in the side area.

5. The method for reducing image density deviation in a laser scanning device according to claim 4, wherein: The parts include a first part, a second part, a third part, a fourth part, a fifth part, a sixth part, a seventh part, an eighth part and a ninth part; The first portion and the ninth portion are symmetrically arranged along the center line of the fifth portion; the second portion and the eighth portion are symmetrically arranged along the center line of the fifth portion; the third portion and the seventh portion are symmetrically arranged along the center line of the fifth portion; and the fourth portion and the sixth portion are symmetrically arranged along the center line of the fifth portion. The luminous intensity of the first part, the second part, the third part, the fourth part and the fifth part decreases in sequence; The luminous intensities of the fifth portion, the sixth portion, the seventh portion, the eighth portion, and the ninth portion increase in sequence.

6. The method for reducing image density deviation in a laser scanning device according to claim 5, wherein: The luminous intensity of the first part is the same as the luminous intensity of the ninth part; the luminous intensity of the second part is the same as the luminous intensity of the eighth part; the luminous intensity of the third part is the same as the luminous intensity of the seventh part; and the luminous intensity of the fourth part is the same as the luminous intensity of the sixth part.

7. The method for reducing image density deviation in a laser scanning device according to claim 6, wherein: The luminous intensity of the second part is 90% of the luminous intensity of the first part; the luminous intensity of the third part is 76% of the luminous intensity of the first part; the luminous intensity of the fourth part is 70% of the luminous intensity of the first part; and the luminous intensity of the fifth part is 66% of the luminous intensity of the first part.

Images