JP5934771B2 - Optical scanning apparatus and image forming apparatus - Google Patents

Description

  The present invention relates to an optical scanning device that scans a light beam and an image forming apparatus that forms an electrostatic latent image on a photoconductor using the optical scanning device.

  2. Description of the Related Art Conventionally, an optical scanning device that is incorporated in an image forming apparatus and forms an electrostatic image on a photosensitive drum by irradiating a laser beam is known. The optical scanning device includes a light source that outputs laser light, a collimator lens that converts the laser light emitted from the light source into a parallel light beam, a polygon mirror that deflects the parallel light beam and scans the photosensitive drum, and a polygon mirror An fθ lens that guides the laser beam deflected by the laser beam to the photosensitive drum, and a housing that accommodates the optical system elements.

  In such an optical scanning device, the scanning position of the laser beam changes depending on the arrangement position of the light source and the collimator lens. Therefore, it is necessary to adjust the arrangement position of the light source and the collimator lens so that the laser beam is irradiated to the correct position on the photosensitive drum. However, adjusting the arrangement position of the light source and the collimator lens in a state in which the optical scanning device is incorporated in the image forming apparatus is not workable.

  Therefore, in order to make it possible to adjust an optical unit including an optical member such as a collimator lens with a single optical scanning device, a technique for forming an opening for adjustment in the housing at a position rearward of the polygon motor as viewed from the light source is known. (For example, refer to Patent Document 1). According to this technique, when the polygon mirror is removed from the optical scanning device, the light beam that has passed through the collimator lens from the light source is emitted from the opening to the outside of the housing. Therefore, by adjusting the optical unit so that the position of the light beam emitted from the opening becomes a predetermined position, the optical unit can be adjusted without incorporating the optical scanning device into the image forming apparatus.

JP 2000-284203 A

  However, in the above-described technology, after adjusting the optical unit without the polygon mirror attached to the housing, it is necessary to perform optical adjustment such as focus adjustment and light amount adjustment after the polygon mirror is attached to the housing. There is a disadvantage that adjustment work becomes complicated. In addition, since the adjustment of the laser beam irradiation position is performed with the polygon mirror removed, it is not possible to make adjustments that take into account the inclination of the rotation axis of the polygon mirror, resulting in a decrease in the adjustment accuracy of the laser beam irradiation position. There was an inconvenience of doing.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an optical scanning device in which the arrangement position of a light source and a lens can be easily adjusted with a polygon mirror attached to a housing, and an image forming apparatus including the optical scanning device. is there.

  An optical scanning device according to the present invention includes a base member, a light emitting unit disposed on one surface of the base member and outputting light, and a light disposed on the one surface and transmitting the light output from the light emitting unit. And a polygon that is arranged on the one surface and reflects light rays transmitted through the lens in a direction substantially parallel to the one surface by rotating about a rotation axis extending in a direction perpendicular to the one surface. A mirror, and a light emitting portion, the lens, and a side wall portion erected on the one surface so as to surround the polygon mirror. The side wall portion is output from the light emitting portion and reflected by the polygon mirror. Between the first non-shielding part that emits the emitted light to the outside of the internal area that is the area surrounded by the side wall part, and the light beam passes through the side wall part between the outside of the internal area and the polygon mirror A second non-shielding portion is formed, and the second non-shielding portion is formed by notching a part of the side wall portion that allows a light beam traveling from the outside of the internal region to the polygon mirror to pass therethrough. A cutout portion, and a second cutout portion formed by cutting out another part of the side wall portion that allows the light reflected by the polygon mirror to pass after passing through the first cutout portion. .

According to this configuration, the light emitting part, the lens, and the polygon mirror are surrounded by the side wall part. And since the 1st non-shielding part is formed in the side wall part, the light beam which is output from the light emitting part and transmitted through the lens and reflected by the polygon mirror is emitted to the outside of the inner region, thereby Can be scanned. Further, since the second non-shielding part is formed on the side wall part in addition to the first non-shielding part, the light beam passes through the second non-shielding part between the outside of the inner region and the polygon mirror. It is possible. Therefore, with the polygon mirror attached to the base member that becomes the housing, the polygon mirror rotation angle is detected by irradiating the polygon mirror with light from the outside through the second non-shielding part and detecting the reflection position of the light ray. Easy to do. If it is easy to detect the rotation angle of the polygon mirror, the light beam reflected by the polygon mirror from the light emitting unit through the lens is detected at the predetermined detection position with the rotation angle of the polygon mirror set to the predetermined rotation angle. Thus, it becomes easy to adjust the arrangement position of the light source and the lens. That is, it becomes easy to adjust the arrangement position of the light source and the lens with the polygon mirror attached to the housing.
According to this structure, the 1st notch part which lets the light which goes to the polygon mirror from the outside of an internal area | region passes, and the 2nd notch part which passes the light reflected by the polygon mirror after passing the 1st notch part Therefore, the cutout portion formed in the side wall portion is compared with the configuration in which the light beam traveling from the outside of the inner region toward the polygon mirror and the light beam reflected by the polygon mirror pass through one cutout portion. Can be reduced. As a result, it becomes easy to increase the rigidity of the side wall.

  The optical scanning device according to the present invention includes a base member, a light emitting unit disposed on one surface of the base member and outputting a light beam, and a light beam disposed on the one surface and output from the light emitting unit. And a lens disposed on the one surface and rotated about a rotation axis extending in a direction perpendicular to the one surface, thereby reflecting light rays transmitted through the lens in a direction substantially parallel to the one surface. And a side wall portion standing on the one side so as to surround the light emitting portion, the lens, and the polygon mirror, and the polygon mirror is output from the light emitting portion to the side wall portion. Between the first non-shielding portion that emits the light beam reflected by the outside to the outside of the inner region that is the region surrounded by the side wall portion, and between the outside of the inner region and the polygon mirror, A second non-shielding portion that passes therethrough, and the second non-shielding portion is a cut formed by cutting out a part of the side wall portion that allows a light beam from the outside of the internal region to pass to the polygon mirror. The cutout portion is located at a position where the light reflected by the polygon mirror after passing through the cutout portion can be emitted outside the inner region through the first non-shielding portion. It may be formed.

According to this configuration, the light emitting part, the lens, and the polygon mirror are surrounded by the side wall part. And since the 1st non-shielding part is formed in the side wall part, the light beam which is output from the light emitting part and transmitted through the lens and reflected by the polygon mirror is emitted to the outside of the inner region, thereby Can be scanned. Further, since the second non-shielding part is formed on the side wall part in addition to the first non-shielding part, the light beam passes through the second non-shielding part between the outside of the inner region and the polygon mirror. It is possible. Therefore, with the polygon mirror attached to the base member that becomes the housing, the polygon mirror rotation angle is detected by irradiating the polygon mirror with light from the outside through the second non-shielding part and detecting the reflection position of the light ray. Easy to do. If it is easy to detect the rotation angle of the polygon mirror, the light beam reflected by the polygon mirror from the light emitting unit through the lens is detected at the predetermined detection position with the rotation angle of the polygon mirror set to the predetermined rotation angle. Thus, it becomes easy to adjust the arrangement position of the light source and the lens. That is, it becomes easy to adjust the arrangement position of the light source and the lens with the polygon mirror attached to the housing.
According to this configuration, it is easy to detect the rotation angle of the polygon mirror by irradiating the polygon mirror with light from the outside through the notch and detecting the reflected light outside through the notch.

  The optical scanning device according to the present invention includes a base member, a light emitting unit disposed on one surface of the base member and outputting a light beam, and a light beam disposed on the one surface and output from the light emitting unit. And a lens disposed on the one surface and rotated about a rotation axis extending in a direction perpendicular to the one surface, thereby reflecting light rays transmitted through the lens in a direction substantially parallel to the one surface. And a side wall portion standing on the one side so as to surround the light emitting portion, the lens, and the polygon mirror, and the polygon mirror is output from the light emitting portion to the side wall portion. Between the first non-shielding portion that emits the light beam reflected by the outside to the outside of the inner region that is the region surrounded by the side wall portion, and between the outside of the inner region and the polygon mirror, A second non-shielding portion that passes through, and the second non-shielding portion transmits light reflected from the polygon mirror through the first non-shielding portion from the outside of the inner region to the side wall portion. It may be a cutout portion formed by cutting out a part of the side wall portion at a position where it can pass through and be emitted to the outside of the internal region.

According to this configuration, the light emitting part, the lens, and the polygon mirror are surrounded by the side wall part. And since the 1st non-shielding part is formed in the side wall part, the light beam which is output from the light emitting part and transmitted through the lens and reflected by the polygon mirror is emitted to the outside of the inner region, thereby Can be scanned. Further, since the second non-shielding part is formed on the side wall part in addition to the first non-shielding part, the light beam passes through the second non-shielding part between the outside of the inner region and the polygon mirror. It is possible. Therefore, with the polygon mirror attached to the base member that becomes the housing, the polygon mirror rotation angle is detected by irradiating the polygon mirror with light from the outside through the second non-shielding part and detecting the reflection position of the light ray. Easy to do. If it is easy to detect the rotation angle of the polygon mirror, the light beam reflected by the polygon mirror from the light emitting unit through the lens is detected at the predetermined detection position with the rotation angle of the polygon mirror set to the predetermined rotation angle. Thus, it becomes easy to adjust the arrangement position of the light source and the lens. That is, it becomes easy to adjust the arrangement position of the light source and the lens with the polygon mirror attached to the housing.
According to this configuration, the light reflected from the polygon mirror after passing through the first non-shielding portion from the outside passes through the notch and is emitted to the outside, and the reflected light is detected outside, so that the polygon It becomes easy to detect the rotation angle of the mirror.

  Moreover, it is preferable to further provide a lid that covers the internal region and the second non-shielding portion.

  According to this configuration, the second non-shielding portion is also covered by the lid that covers the internal region, so that the possibility that dust and dirt enter the inside of the optical scanning device from the second non-shielding portion is reduced.

  In addition, the image forming apparatus according to the present invention forms an electrostatic latent image by scanning the surface with the above-described optical scanning device and a light beam that has passed through the first non-shielding portion of the optical scanning device. A photosensitive member; a developing unit that develops the electrostatic latent image to form a toner image; and a transfer unit that transfers the toner image to a sheet.

  According to this configuration, the optical scanning device used in the image forming apparatus can have a structure in which the arrangement position of the light source and the lens can be easily adjusted with the polygon mirror attached to the housing.

  According to the optical scanning device and the image forming apparatus having such a configuration, it is easy to adjust the arrangement positions of the light source and the lens in a state where the polygon mirror is attached to the housing.

1 is a cross-sectional view illustrating a schematic configuration of a printer including an optical scanning device according to an embodiment of the present invention. It is explanatory drawing for demonstrating an example of a structure and manufacturing method of the optical scanning device shown in FIG. It is the perspective view which looked at the flame | frame shown in FIG. 2 from back. FIG. 4 is a perspective view of the optical scanning device with the lid attached to the frame shown in FIG. 2 as seen from the rear. It is a screen figure which shows an example of the image displayed on a display part, when the attachment position of a laser unit or a collimator lens has shifted | deviated. It is a screen figure which shows an example of the image displayed on a display part when the attachment position of a laser unit or a collimator lens is correct. It is explanatory drawing which shows the modification of the optical scanning device and manufacturing method which are shown in FIG. It is explanatory drawing which shows the modification of the manufacturing method shown in FIG.

  Embodiments according to the present invention will be described below with reference to the drawings. In addition, the structure which attached | subjected the same code | symbol in each figure shows that it is the same structure, The description is abbreviate | omitted.

  FIG. 1 is a cross-sectional view illustrating a schematic configuration of a printer including an optical scanning device according to an embodiment of the present invention. As shown in FIG. 1, the printer 1 (an example of an image forming apparatus) includes an image forming unit 100, an optical scanning device 104, and paper feed cassettes 210 and 220 in a box-shaped casing 101. Has been. The paper feed cassettes 210 and 220 are detachably disposed below the printer 1.

  The image forming unit 100 includes a charging device 102, a photosensitive drum 103 (an example of a photosensitive member), a developing device 105 (an example of a developing unit), a transfer roller 106 (an example of a transfer unit), a cleaning device 107, and a fixing roller unit 108. It has.

  In the image forming unit 100, the charging device 102 uniformly charges the peripheral surface of the photosensitive drum 103 that rotates in the direction A in the drawing. Then, laser light B (an example of the first light beam) based on print data input from the outside is irradiated onto the peripheral surface of the photosensitive drum 103 by the optical scanning device 104 to form an electrostatic latent image, and the photosensitive member By supplying toner from the developing device 105 to the electrostatic latent image formed on the peripheral surface of the drum 103, a toner image is formed on the peripheral surface of the photosensitive drum 103.

  The paper feed cassettes 210 and 220 contain paper P (an example of a sheet). A conveyance path 300 is disposed between the sheet feeding cassettes 210 and 220 and the image forming unit 100. In the conveyance path 300, a pair of paper feed rollers 213 and 223, a pair of conveyance rollers 214 and 224, and a pair of registration rollers 215 are provided.

  Then, the paper P is fed from the paper feed cassettes 210 and 220 to the transport path 300 by the pickup rollers 212 and 222, the paper P is transported toward the photosensitive drum 103 by the transport path 300, and the photoconductor by the transfer roller 106. The toner image on the surface of the drum 103 is transferred to the surface of the paper P. The toner remaining on the photosensitive drum 103 after the transfer is removed by a cleaning device 107, and the remaining charge on the photosensitive drum 103 thereafter is removed by a static eliminator (not shown).

  The paper P onto which the toner image on the photosensitive drum 103 is transferred by the transfer roller 106 is conveyed to the fixing roller unit 108 where the toner image on the paper P is fixed. The sheet P is discharged to the sheet discharge tray 119 by the discharge roller pair 110 as it is (or after being reversed and printed on both sides by an unillustrated switchback unit).

  A right cover 111 is provided on the right side surface of the housing 101, and a left cover 113 is provided on the left side surface of the housing 101. A shaft 112 is provided at the lower end of the right cover 111. The right cover 111 is supported by a shaft 112 and can be opened and closed by rotating around the shaft. A shaft 114 is provided at the lower end of the left cover 113. The left cover 113 is supported by a shaft 114 and can be opened and closed by rotating around the shaft.

  The image forming apparatus is not limited to a printer, and may be a copier, a facsimile machine, a multifunction machine, or the like.

  FIG. 2 is a perspective view showing an example of the configuration of the optical scanning device 104 shown in FIG. FIG. 2 shows a state in which a cover that covers the upper part is removed from the optical scanning device 104 and CCD (Charge Coupled Device) sensors 501, 503, an external light source 502, and an inspection device 504 are arranged around the optical scanning device 104. Show.

  The optical scanning device 104 includes a substantially rectangular bottomed container-shaped frame 143 that is open on one side, and a lid 151 that will be described later that closes the opening of the frame 143. The frame 143 and the lid 151 are combined to form the housing of the optical scanning device 104.

  The frame 143 includes a plate-like base member 141 serving as a bottom portion and a side wall portion 142 erected substantially vertically from the periphery of the base member 141. A laser unit 20 (an example of a light emitting unit), a collimator lens 23, an aperture 24, a polygon mirror 26, and an fθ lens 28 are disposed on the base member 141, and these optical members are surrounded by the side wall 142. Yes. A region surrounded by the side wall 142 is an internal region in the housing.

  Hereinafter, when the optical scanning device 104 is attached to the printer 1, the side facing the photosensitive drum 103 is the front side, the opposite side is the rear side, the right side is the right side, and the left side is the left side. Is the front side wall 142F, the rear wall is the rear side wall 142B, the right side wall is the right side wall 142R, and the left side wall is the left side wall 142L.

  A cutout 146 (an example of a first non-shielding portion) extending in the main scanning direction is formed on the front side wall 142F. In the vicinity of the right end of the rear side wall 142B, a bulging portion 148 that bulges outward in a substantially arc shape is formed.

  A recess 147 is formed in a partial region of the base member 141 near the bulging portion 148. A polygon motor 27 having a rotation axis extending in a direction perpendicular to the bottom surface of the recess 147 is disposed on the bottom surface of the recess 147. A polygon mirror 26 is attached to the rotation shaft of the polygon motor 27. The polygon mirror 26 is a polygon mirror in which a reflecting surface is formed along each side of a regular hexagon, for example. The polygon mirror 26 is rotated at a constant speed by a polygon motor 27.

  The laser unit 20 is configured such that a substantially cylindrical semiconductor laser 22 is erected on one surface of a substrate 21.

  In addition, a first holding member 144 and a second holding member 145 are attached in the vicinity of the left side wall 142L on the upper surface of the base member 141. A minute gap is provided between the left side wall 142L and the first holding member 144 and between the left side wall 142L and the second holding member 145. The first holding member 144 and the second holding member 145 are arranged to face each other with an interval slightly larger than the diameter of the semiconductor laser 22. Then, the semiconductor laser 22 is fitted between the first holding member 144 and the second holding member 145 so that the substrate 21 is sandwiched between the first holding member 144 and the second holding member 145 and the left side wall 142L. As described above, the laser unit 20 is attached to the upper surface of the base member 141.

  As a result, the substrate 21 is erected on the inner surface of the base member 141, and the emission direction of the laser light from the semiconductor laser 22 is directed in a direction substantially parallel to the inner surface of the base member 141. Further, the mounting position of the substrate 21 can be adjusted along the inner surface of the left side wall 142L.

  When the mounting position of the substrate 21 is moved along the inner surface of the left side wall 142L, the laser beam B output from the semiconductor laser 22 moves in a direction perpendicular to the base member 141 and in a parallel direction. That is, by adjusting the mounting position of the substrate 21 along the inner surface of the left side wall 142L, the irradiation position of the laser beam B can be adjusted in the vertical direction and the parallel direction with respect to the base member 141.

  The collimator lens 23 is a lens that converts the laser beam B output from the semiconductor laser 22 into a parallel light beam. The collimator lens 23 is attached in a direction in which the optical axis is parallel to the substantially plate-like attachment member 25. The attachment member 25 is attached to the inner surface of the base member 141 so that the laser beam B passes through the collimator lens 23. The attachment member 25 is slidable with respect to the base member 141. The attachment position of the collimator lens 23 can be adjusted by sliding the attachment member 25.

  The aperture 24 narrows down the diameter of the laser beam B that has been converted into a parallel light beam by the collimator lens 23 to a predetermined size. The laser beam B that has passed through the collimator lens 23 and the aperture 24 strikes the reflecting surface of the polygon mirror 26.

  The reflection angle of the laser beam B that has hit the reflecting surface of the polygon mirror 26 changes as the polygon mirror 26 rotates, and the laser beam B is scanned in the main scanning direction.

  The fθ lens 28 is a lens that is long in the main scanning direction. The fθ lens 28 is disposed between the notch 146 and the polygon mirror 26. The fθ lens 28 adjusts the optical path angle of the laser beam B emitted from the polygon mirror 26 and irradiates the laser beam B vertically on the surface of the photosensitive drum 103 disposed at a position facing the notch 146. . Thereby, the fθ lens 28 converts the scanning of the laser beam B from constant angular velocity motion to constant velocity motion.

  The laser beam B that has passed through the fθ lens 28 is emitted from the notch 146 to the outside of the housing of the optical scanning device 104.

  The bulging portion 148 is formed with a first through hole 31 and a second through hole. The first through hole 31 and the second through hole are formed in the bulging portion 148 at a position facing the reflecting surface in the outer peripheral direction of the polygon mirror 26. Specifically, a virtual plane including a locus of a line obtained by rotating a line extending from the rotation axis of the polygon mirror 26 around the rotation axis about the rotation axis intersects the bulging portion 148. The first through hole 31 and the second through hole are formed on the line to be performed.

FIG. 3 is a perspective view of the frame 143 shown in FIG. 2 as viewed from the rear. Ribs 35 are erected on the periphery of the first through hole 31 and the second through hole 32 outside the rear side wall 142B. Further, a light shielding wall 33 erected so as to surround the first through hole 31 is formed around the first through hole 31 outside the rear side wall 142B. A light shielding wall 34 is formed around the second through hole outside the rear side wall 142B so as to surround the second through hole.

  The light shielding walls 33 and 34 are connected to the rib 35. Thereby, the light shielding walls 33 and 34 also function as a part of the rib 35. As a result, the rigidity of the frame 143 is increased.

  FIG. 4 is a rear perspective view of the optical scanning device 104 in a state where the lid 151 is attached to the frame 143 shown in FIG. The lid 151 shown in FIG. 4 includes a blocking portion 36 that closes the first through hole 31 and the second through hole 32 when attached to the frame 143. As a result, when the cover 151 is attached to the frame 143, the first through hole 31 and the second through hole 32 are closed, so that the dust from the first through hole 31 and the second through hole 32 to the inside of the housing of the optical scanning device 104. And dust are prevented from entering. In addition, since the first through hole 31 and the second through hole 32 are shielded from light, the light that has entered the housing from the first through hole 31 and the second through hole 32 passes through the notch 146 and passes through the photosensitive drum. 103 is prevented.

  Next, a method for manufacturing the optical scanning device 104 configured as described above will be described. With reference to FIG. 1, the inspection apparatus 504 includes a control unit 541 and a display unit 542. The control unit 541 includes, for example, a CPU (Central Processing Unit) that executes predetermined arithmetic processing, a ROM (Read Only Memory) that stores a predetermined program, a RAM (Random Access Memory) that temporarily stores data, and its Peripheral circuits are provided. The display unit 542 is a display device such as a liquid crystal display device. CCD sensors 501 and 503 are connected to the control unit 541.

  In the manufacturing process of the optical scanning device 104, after the temporary assembly of the optical scanning device 104 shown in FIG. 2 is completed, the manufacturing operator determines that the laser beam B output from the laser unit 20 is in the correct position on the photosensitive drum 103. The mounting positions of the laser unit 20 and the collimator lens 23 are adjusted so that scanning of the optical scanning device 104 is completed. Note that the manufacturer may adjust the attachment position of only one of the laser unit 20 and the collimator lens 23.

  In order to adjust the mounting position of the laser unit 20 and the collimator lens 23 so that the laser beam B output from the laser unit 20 scans the correct position of the photosensitive drum 103, the rotation angle of the polygon mirror 26 is set in advance. When the set angle R is set, the laser beam B reflected by the polygon mirror 26 needs to be detected at a preset first light beam detection position.

  Therefore, the external light source 502 and the CCD sensor 503 allow the laser light C output from the external light source 502 to pass through the first through hole 31 when the rotation angle of the polygon mirror 26 is a preset detection angle S. They are arranged so as to be in a positional relationship in which they are reflected by the polygon mirror 26 and irradiated to the detection coordinates of the light receiving area of the CCD sensor 503 through the second through hole.

  The set angle R and the detection angle S may be the same angle. When the detected angle S is different from the set angle R, the time from when the rotation angle of the polygon mirror 26 becomes the detected angle S to the set angle R is stored in advance in the ROM of the control unit 541 as the delay time Td, for example. ing.

  The CCD sensor 501 is disposed such that the light receiving surface of the CCD sensor 501 is disposed at a position (distance) that is the surface position of the photosensitive drum 103 in a state where the optical scanning device 104 is attached to the printer 1. Further, when the laser unit 20 and the collimator lens 23 are attached at the correct positions, the CCD sensor 501 is set in advance in the light receiving area of the CCD sensor 501 when the rotation angle of the polygon mirror 26 is the set angle R. It arrange | positions so that the laser beam B may be irradiated to a target coordinate.

  Then, the manufacturing operator supplies power to the optical scanning device 104 to rotate the polygon motor 27 and emit the semiconductor laser 22, and the laser beam B is transmitted to the polygon mirror via the collimator lens 23 and the aperture 24. 26 is irradiated.

  Next, the manufacturing worker irradiates the polygon mirror 26 with the laser beam B from the semiconductor laser 22 and applies the laser beam C (an example of the second beam) output from the external light source 502 to the polygon through the first through hole 31. The mirror 26 is irradiated.

  Then, the laser beam B is reflected by the polygon mirror 26, and the laser beam B is scanned over a line-shaped region including the light receiving surface of the CCD sensor 501. On the other hand, when the rotation angle of the polygon mirror 26 reaches the detection angle S, the laser light C reflected by the polygon mirror 26 passes through the second through hole and is set in advance in a light receiving area of the CCD sensor 503. The coordinates are irradiated. The reference coordinates correspond to the second light ray detection position.

  Next, when the control unit 541 detects that the laser beam C is irradiated to the reference coordinates of the CCD sensor 503, the image is captured by the CCD sensor 501 at a timing synchronized with the timing at which the laser light C is irradiated to the reference coordinates. The image is displayed on the display unit 542 together with a positioning mark M (for example, a cross mark) indicating the target coordinates.

  Here, “the timing synchronized with the timing at which the laser beam C is applied to the reference coordinates” means that when the set angle R and the detection angle S are the same angle, “the laser light C is applied to the reference coordinates. When the detection angle S is different from the set angle R, it means “a timing at which the delay time Td has elapsed from the timing at which the laser light C is applied to the reference coordinates”. That is, the “timing synchronized with the timing at which the laser light C is applied to the reference coordinates” is the timing at which the rotation angle of the polygon mirror 26 is the set angle R.

  FIG. 5 is a screen diagram illustrating an example of an image G displayed on the display unit 542 when the mounting position of the laser unit 20 or the collimator lens 23 is shifted. In the image G shown in FIG. 5, a cross-shaped positioning mark M is displayed in the vicinity of the approximate center. The position where the cross of the positioning mark M intersects indicates the target coordinate Po, and the laser beam B hitting the light receiving surface of the CCD sensor 501 is displayed in a spot shape at the lower left position of the target coordinate Po.

  The image G is an image at a timing synchronized with the timing at which the laser light C is applied to the reference coordinates, that is, an image captured by the CCD sensor 501 at the timing when the rotation angle of the polygon mirror 26 is the set angle R. is there.

  Therefore, in the image G, when the laser beam B is displayed at a position different from the target coordinate Po, it indicates that the mounting position of the laser unit 20 or the collimator lens 23 is shifted.

  Therefore, the manufacturing operator adjusts the mounting position of the laser unit 20 or the collimator lens 23 so that the display position of the laser beam B coincides with the target coordinate Po while looking at the display screen of the display unit 542. When the mounting position of the laser unit 20 or the collimator lens 23 is moved in the vertical direction, the laser beam B also moves in the vertical direction, and when the mounting position of the laser unit 20 or the collimator lens 23 is moved in the horizontal direction, the laser beam B is also moved in the horizontal direction. Move to.

  As shown in FIG. 6, when the display position of the laser beam B matches the target coordinate Po in the image G, the attachment positions of the laser unit 20 and the collimator lens 23 are correctly adjusted. In this way, the optical scanning device 104 is manufactured by adjusting the mounting positions of the laser unit 20 and the collimator lens 23.

  As described above, the above-described manufacturing method irradiates the polygon mirror 26 through the first through hole 31 while irradiating the polygon mirror 26 with the laser beam B through the collimator lens 23 from the laser unit 20. The laser beam B reflected by the polygon mirror 26 is the target coordinates of the CCD sensor 501 at the timing synchronized with the timing when the laser beam C reflected by the polygon mirror 26 is detected by the reference coordinates of the CCD sensor 503. Adjusting the position of at least one of the laser unit 20 and the collimator lens 23 so as to be detected at Po. As a result, the arrangement positions of the laser unit 20 and the collimator lens 23 can be easily adjusted with the polygon mirror 26 still attached to the frame 143.

  Such a manufacturing method can be implemented by forming the first through hole 31 and the second through hole 32 in the side wall 142 of the optical scanning device 104. That is, in the optical scanning device 104 in which the first through hole 31 and the second through hole 32 are formed in the side wall 142, the laser unit 20 and the collimator lens 23 are arranged with the polygon mirror 26 attached to the frame 143. It is easy to adjust the installation position.

  Moreover, since the side wall part 142 is attached to the base member 141, the rigidity of the base member 141 is improved. That is, when the rigidity of the base member 141 is low, the positional relationship among the laser unit 20, the collimator lens 23, the polygon motor 27, and the fθ lens 28 attached to the base member 141 changes due to the influence of the deflection of the base member 141. Further, the adjustment accuracy of the attachment position of the laser unit 20 and the collimator lens 23 is lowered. However, since the base member 141 includes the side wall part 142 and has increased rigidity, and the first through hole 31 and the second through hole 32 are formed in the side wall part 142, the laser unit 20 and the collimator lens 23 are formed. The adjustment accuracy of the mounting position of is improved. In addition, compared to the case where one large through hole is formed instead of the first through hole 31 and the second through hole 32, it is better to form the first through hole 31 and the second through hole 32 in the side wall portion 142. As a result of being able to reduce the size of the through hole, the rigidity of the side wall 142 can be increased.

  Further, since the light shielding walls 33 and 34 are erected on the outer surface of the side wall portion 142 so as to surround the first through hole 31 and the second through hole 32, respectively, when performing the above manufacturing method, The possibility that disturbing light enters the internal region from the lateral direction of the light shielding walls 33 and 34 is reduced. As a result, disturbance light is received by the CCD sensor 501 and the CCD sensor 503, and the possibility that the adjustment accuracy of the attachment positions of the laser unit 20 and the collimator lens 23 is reduced is reduced.

  Instead of providing the first through hole 31 and the second through hole 32, for example, one long hole that includes the first through hole 31 and the second through hole 32 may be provided. Moreover, the 1st through-hole 31 and the 2nd through-hole 32 are not restricted circularly, For example, a polygon may be sufficient.

  Moreover, the 2nd non-shielding part should just pass the laser beam C, for example, a part of side wall part 142 may be notched, and may be comprised. For example, when the frame 143 is manufactured by integral shaping with a resin, the die has a simpler shape than the first through-hole 31 and the second through-hole 32 as the second non-shielding portion. Therefore, it is easy to reduce the manufacturing cost. However, it is preferable that the through hole is formed in the side wall part 142 rather than the structure in which a part of the side wall part 142 is cut out, because the rigidity of the side wall part 142 can be increased.

  In addition, if the side wall 142 is not erected on the base member 141, the rigidity of the base member 141 is reduced, and the base member 141 is easily bent. As a result, the laser unit 20 attached to the base member 141, The positional relationship among the collimator lens 23, the aperture 24, the polygon mirror 26, and the fθ lens 28 may be shifted, and the adjustment accuracy of the mounting positions of the laser unit 20 and the collimator lens 23 may be reduced. However, in the optical scanning device 104, since the side wall 142 is provided upright on the base member 141 and the through hole is formed in the side wall 142, the side wall 142 is not provided upright on the base member 141. As a result of the rigidity of the base member 141 being increased compared to the case, the adjustment accuracy of the mounting positions of the laser unit 20, the collimator lens 23, the aperture 24, the polygon mirror 26, and the fθ lens 28 attached to the base member 141 is improved.

  In addition, as shown in FIG. 7, it is good also as a structure which does not form the 2nd through-hole in the side wall part 142. As shown in FIG. Then, the first through hole 31 may be formed on the wall surface of the side wall portion 142 adjacent to the wall surface where the notch 146 is formed.

  In this case, when adjusting the mounting positions of the laser unit 20 and the collimator lens 23, the CCD sensor 503 is disposed at a position facing the notch 146. With such a configuration, the laser light C output from the external light source 502 is reflected by the polygon mirror 26, passes through the fθ lens 28, and is irradiated on the CCD sensor 503.

  Even with such a configuration, the same manufacturing method as described above can be performed, and it is easy to adjust the arrangement positions of the laser unit 20 and the collimator lens 23 with the polygon mirror 26 attached to the frame 143. is there.

  Further, since the laser beam B irradiated from the optical scanning device 104 to the photosensitive drum 103 is scanned in the main scanning direction, the optical characteristics of the optical scanning device 104 are adjusted over the entire scanning range in the main scanning direction. In some cases, a plurality of CCD sensors are arranged along the main scanning direction at a position facing the notch 146, and the laser beam B at each position in the main scanning direction is detected. Therefore, if a part of the CCD sensor for detecting the laser beam B at each position in the main scanning direction is used as the CCD sensors 501 and 503, the positions of the laser unit 20 and the collimator lens 23 are adjusted. Therefore, it is not necessary to prepare the CCD sensors 501 and 503, so that the cost for carrying out the above manufacturing method is reduced.

  On the other hand, in the arrangement of the CCD sensor 503 shown in FIG. 7, the laser light C detected by the CCD sensor 503 is refracted by the fθ lens 28. Therefore, as compared with the configuration shown in FIG. 7, the configuration in which the rotation angle of the polygon mirror 26 is detected using the laser light C that does not pass through the fθ lens 28 as shown in FIG. The angle detection accuracy is improved.

  In addition, you may form the light shielding wall 33 and the rib 35 also around the 1st through-hole 31 shown in FIG. 7 similarly to FIG. In this case, similarly to the case where the light shielding walls 33 and the ribs 35 shown in FIG. 3 are provided, the possibility of disturbance light entering the internal region from the lateral direction of the light shielding walls 33 is reduced when the manufacturing method is performed, and the frame 143 The rigidity of the is increased. Moreover, the cover body 151 may be provided with the closing part 36 in the position which closes the 1st through-hole 31 shown in FIG. As a result, when the lid 151 is attached to the frame 143, the first through hole 31 is closed, so that dust and dust can be prevented from entering the housing of the optical scanning device 104 from the first through hole 31. Further, since the first through hole 31 is shielded from light, the light that has entered the housing from the first through hole 31 is prevented from hitting the photosensitive drum 103 through the notch 146.

  Further, as shown in FIG. 8, the arrangement of the external light source 502 and the CCD sensor 503 when the above manufacturing method is performed may be replaced with the arrangement shown in FIG.

DESCRIPTION OF SYMBOLS 1 Printer 20 Laser unit 21 Board | substrate 22 Semiconductor laser 23 Collimator lens 24 Aperture 25 Mounting member 26 Polygon mirror 27 Polygon motor 28 f (theta) lens 31 1st through-hole 32 2nd through-hole 33,34 Light-shielding wall 35 Rib 36 Blocking part 100 Image formation Part 103 Photosensitive drum 104 Optical scanning device 105 Developing device 106 Transfer roller 141 Base member 142 Side wall part 143 Frame 144 First holding member 145 Second holding member 146 Notch part 148 Swelling part 151 Lids 501 and 503 CCD sensor 502 External light source 504 Inspection device 541 Control unit 542 Display unit B, C Laser beam G Image M Positioning mark Po Target coordinate Td Delay time

Claims (5)

A base member;
A light emitting unit disposed on one side of the base member and outputting a light beam;
A lens disposed on the one surface and transmitting the light beam output from the light emitting unit;
A polygon mirror that is disposed on the one surface and reflects a light beam transmitted through the lens in a direction substantially parallel to the one surface by rotating about a rotation axis extending in a direction perpendicular to the one surface;
A side wall portion standing on the one surface so as to surround the light emitting portion, the lens, and the polygon mirror;
In the side wall,
A first non-shielding part that emits a light beam output from the light emitting part and reflected by the polygon mirror to the outside of an internal area that is an area surrounded by the side wall part;
Between the outside of the internal region and the polygon mirror, a second non-shielding part through which light passes through the side wall part is formed,
The second non-shielding part is
A first cutout part formed by cutting out a part of the side wall part for allowing a light beam from the outside of the internal region to pass to the polygon mirror;
An optical scanning device comprising: a second cutout part formed by cutting out another part of the side wall part through which the light beam reflected by the polygon mirror passes after passing through the first cutout part. A base member;
A light emitting unit disposed on one side of the base member and outputting a light beam;
A lens disposed on the one surface and transmitting the light beam output from the light emitting unit;
A polygon mirror that is disposed on the one surface and reflects a light beam transmitted through the lens in a direction substantially parallel to the one surface by rotating about a rotation axis extending in a direction perpendicular to the one surface;
A side wall portion standing on the one surface so as to surround the light emitting portion, the lens, and the polygon mirror;
In the side wall,
A first non-shielding part that emits a light beam output from the light emitting part and reflected by the polygon mirror to the outside of an internal area that is an area surrounded by the side wall part;
Between the outside of the internal region and the polygon mirror, a second non-shielding part through which light passes through the side wall part is formed,
The second non-shielding part is
A cutout part formed by cutting out a part of the side wall part, which allows a light beam traveling from the outside of the internal region to the polygon mirror to pass therethrough,
The notch is
An optical scanning device formed at a position where light that has passed through the notch and reflected by the polygon mirror can pass through the first non-shielding portion and be emitted to the outside of the internal region. A base member;
A light emitting unit disposed on one side of the base member and outputting a light beam;
A lens disposed on the one surface and transmitting the light beam output from the light emitting unit;
A polygon mirror that is disposed on the one surface and reflects a light beam transmitted through the lens in a direction substantially parallel to the one surface by rotating about a rotation axis extending in a direction perpendicular to the one surface;
A side wall portion standing on the one surface so as to surround the light emitting portion, the lens, and the polygon mirror;
In the side wall,
A first non-shielding part that emits a light beam output from the light emitting part and reflected by the polygon mirror to the outside of an internal area that is an area surrounded by the side wall part;
Between the outside of the internal region and the polygon mirror, a second non-shielding part through which light passes through the side wall part is formed,
The second non-shielding part is
One of the side wall portions is located at a position where light reflected from the polygon mirror through the first non-shielding portion from the outside of the internal region can be emitted to the outside of the internal region through the side wall portion. The optical scanning device which is a notch part formed by notching a part. The optical scanning device according to any one of claims 1 to 3, further comprising a lid for covering the said inner region and the second non-shielding portion. The optical scanning device according to any one of claims 1 to 4 ,
A photosensitive member on which an electrostatic latent image is formed by scanning the surface with a light beam that has passed through the first non-shielding portion of the optical scanning device;
A developing unit for developing the electrostatic latent image to form a toner image;
An image forming apparatus comprising: a transfer unit that transfers the toner image to a sheet.

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