JP2010032682A - Optical scanner and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an optical scanner including a reflecting mirror in an optical path between a light source and a light polarizer, and capable of restraining an image from being affected by a flare light beam, by restraining the flare light beam emitted from the light source from getting incident onto a face to be scanned without passing the vicinity of the reflecting mirror and getting incident into the light polarizer, and to provide an image forming apparatus. <P>SOLUTION: A writing device 55 as the optical scanner includes the first LD 1a and the second LD 1b as the light source; a plurality of Fθ lenses 12 as a scanning optical system for guiding and image-focusing a scanning light beam SL and a synchronization light beam BDL, which are deflected light beams deflection-scanned by a polygon mirror 9 for deflecting a light beam emitted from the light source, onto a corresponding photoreceptor surface; and a return mirror 7 as a reflecting mirror for returning the light beam emitted from the light source to be reflected toward the polygon mirror 9. The device is further provided with, in a position extended from a reflecting face of the return mirror 7, the third shielding plate 66 as a shielding member for shielding the light. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an optical scanning device mounted on an image forming apparatus such as a copying machine, a facsimile machine, or a printer, and an image forming apparatus provided with the optical scanning device.

  2. Description of the Related Art Conventionally, image forming apparatuses such as printers, copiers, facsimiles, and multifunction devices having these combined functions irradiate an image carrier (for example, a photosensitive member) with a light beam emitted from a light source to write a latent image. An optical scanning device is provided. In such an image forming apparatus, the latent image formed on the image carrier is developed to be a visible image, and then the visible image is directly transferred from the image carrier or via an intermediate transfer member to the transfer material. After the transfer, the visible image on the transfer material is fixed to obtain an image. In addition, as a color image forming apparatus, the latent image formed on each image carrier is developed and visualized, and then a transfer material such as recording paper carried on a transfer conveyance belt or the like is carried on each image carrier. The transfer part of the body is transferred, the visible image of each color formed on each image carrier is transferred to be superimposed on the transfer material, and the visible image transferred on the transfer material is fixed to obtain an image. is there.

Conventionally, in this type of image forming apparatus, a light beam (flare) that does not contribute to image formation emitted from a semiconductor laser unit (hereinafter referred to as “LD unit”) as a light source unit in which a semiconductor laser is disposed as a light source provided in the optical scanning device. There has been proposed a configuration for preventing light rays) from reaching the surface to be scanned and degrading image formation quality.
The image forming apparatus described in Patent Document 1 polarizes flare light generated by a side lobe of an LD or internal reflection of an LD unit among light emitted from a semiconductor laser (hereinafter referred to as “LD”) as a light source. The shield member integrated with the cover of the device is shielded to prevent flare rays from reaching the surface to be scanned. Further, a configuration for shielding flare light by a shielding member integrated with an optical housing that is an exterior of the LD unit is also described.

Patent Document 2 and Patent Document 3 include a multiple beam scanning device as an optical scanning device, and monitor light emitted from the back surface of the LD as a light source is diffused and emitted from the LD unit as diffused light. Even in this case, an image forming apparatus is described that prevents diffused light from reaching the surface to be scanned and degrading image formation quality. In the image forming apparatus described in Patent Document 2, the light source unit is arranged so that the diffused light from the LD is irradiated to the cover of the polarizer, thereby preventing the diffused light from reaching the scanned surface. Yes. In the image forming apparatus described in Patent Document 3, each member is arranged so that diffused light from a plurality of LDs intersect each other, and a shielding member is provided at a position where the diffused light from the plurality of LDs intersects each other to shield the diffused light. This prevents the diffused light from reaching the surface to be scanned.
Further, in the optical scanning devices described in Patent Documents 1 to 3, a reflecting mirror is arranged on the optical path between the light beam emitted from the light source and the polarizer that polarizes the light, and the optical path is folded back to make the optical scanning device compact in layout. We are trying to make it. In these optical scanning devices, flare rays are shielded by providing a shielding member on the optical path between the light source and the reflecting mirror.

Japanese Patent No. 4008262 Japanese Patent No. 3875813 Japanese Patent No. 4077191

However, in the optical scanning device in which the optical path is turned back by the reflecting mirror, the configurations of Patent Documents 1 to 3 may not prevent the image formation quality from being deteriorated by the flare light.
FIG. 14 is a block diagram showing an example of a conventional optical scanning device. In the writing device 55 as the optical scanning device shown in FIG. 14, the light beams emitted from the first LD 1a and the second LD 1b as the light sources are transmitted through the first collimator lens 2a and the second collimator lens 2b, respectively. The light is emitted from the LD unit 3 as a principal ray 4a and a second principal ray 4b. The first principal ray 4 a and the second principal ray 4 b each pass through the aperture 5, pass through the cylindrical lens 6, are reflected by the folding mirror 7 that is a reflecting mirror, and enter the polygon mirror 9. The polygon mirror 9 which is a polarizer is rotated by a polygon motor 10, and the first principal ray 4 a and the second principal ray 4 b contributing to image formation are incident on the rotating polygon mirror 9 and reflected, thereby scanning light SL. And the sync ray BDL. In the writing device 55 shown in FIG. 14, when the front-back direction of the paper surface is the height direction, the first LD 1 a and the second LD 1 b are arranged at the same height, and the first principal ray 4 a The second principal ray 4b travels on the same optical path until it enters the polygon mirror 9.
The scanning light beam SL passes through the Fθ lens 12 and then reaches the surface of the photoconductor 40 that is the surface to be scanned to form a latent image. In addition, the synchronization light beam BDL is reflected by the synchronization light reflection mirror 11a and reaches the synchronization detection plate 11, and then converted into a signal, which is used to control the light emission timing of the first LD 1a and the second LD 1b. Here, the folding mirror 7 is fixed to an optical housing (not shown) by a leaf spring 8 which is a fixing member.

  In the writing device 55 as such an optical scanning device, the reflected light of the side lobes of the first LD 1a and the second LD 1b and the edge surfaces (the inner surfaces of the lens side surfaces) of the first collimator lens 2a and the second collimator lens 2b. In addition, a light beam that does not contribute to image formation, such as the internally reflected light of the LD unit 3, which is different from the first principal light beam 4 a and the second principal light beam 4 b may be emitted from the LD unit 3. That is, as shown in FIG. 14, the first flare light beam FLa1 (in the drawing, the right side of the traveling direction of the first principal light beam 4a) and the second flare light beam FLa2 (in the drawing, The first principal ray 4a on the left side in the traveling direction), the third flare ray FLb3 (on the right side in the traveling direction of the second principal ray 4b in the figure) and the fourth flare ray FLb4 (shown on both sides in the traveling direction of the second principal ray 4b). This is the left side of the second principal ray 4b in the traveling direction). Similar to the optical writing device described in Patent Document 1, the first flare beam FLa1 and a part of the third flare beam FLb3 are blocked by providing the first shielding plate 64 attached to the cover of the polygon motor 10. Is possible. In addition, a part of the second flare light beam FLa2 and the fourth flare light beam FLb4 can be blocked by the second shielding plate 65 attached to the optical housing (not shown). A part of the second flare beam FLa2 that is not blocked by the second shielding plate 65 passes through the cylindrical lens 6, is reflected by the folding mirror 7, enters the polygon mirror 9, and becomes the scanning beam SL or the synchronizing beam BDL. It becomes a mixed state. On the other hand, most of a part of the third flare light beam FLb3 that is not blocked by the first shielding plate 64 is transmitted through the cylindrical lens 6, reflected by the folding mirror 7, and incident on the polygon mirror 9 to be scanned. It becomes a state mixed with SL or sync beam BDL. However, a part of the third flare beam FLb3 passes through the cylindrical lens 6 and then does not enter the folding mirror 7 but passes through the Fθ lens 12 and reaches the photosensitive member 40. Become.

  Since the flare ray has a smaller amount of energy than the chief ray, the flare ray is incident on the polygon mirror 9 in the same manner as the chief ray and is mixed with the scanning ray SL or the synchronization ray BDL. The polygon mirror 9 is scattered by being polarized, and there is almost no influence on the image. However, since the flare beam that reaches the photoconductor 40 without entering the folding mirror 7 does not enter the polygon mirror 9 but reaches the photoconductor 40, the second LD 1b is emitting light. Is in a state where a specific portion on the photoreceptor 40 is always exposed. For this reason, black streaks and black bands extending in the sub-scanning direction are generated at portions corresponding to positions on the photoreceptor 40 on the image generated by the image forming apparatus where the photoreceptor arrival flare MFL is irradiated. , Significantly reduce the image quality.

In order to prevent such deterioration in image quality, it is necessary to shield the photoreceptor arrival flare MFL, which is a part of the third flare light beam FLb3, so as not to reach the photoreceptor.
However, since the third flare beam FLb3 that causes the photoreceptor arrival flare MFL is emitted from the second LD 1b, the photoreceptor arrival flare MFL travels on the same scanning plane as the two principal rays. is there. As shown in FIG. 14, the photoreceptor arrival flare MFL passes on the optical path of the first principal ray 4 a until just before the first principal ray 4 a enters the folding mirror 7. In the configuration in which the shielding member is provided in the optical path between the light source and the reflecting mirror, it is not possible to shield only the photoreceptor arrival flare MFL without shielding the first principal ray 4a.
Further, since the photoreceptor arrival flare MFL travels on the same scanning plane as the two principal rays, only the photoreceptor arrival flare MFL that has entered the passage region of the scanning ray SL and the synchronization ray BDL contributing to image formation is shielded. It is difficult. For this reason, since it is difficult to block the optical path after the two principal rays are deflected by the polygon mirror 9, the optical path on the optical path from when the photoreceptor arrival flare MFL is emitted from the LD unit 3 to the incident on the polygon mirror 9 is difficult. It is necessary to shield with.
In the description using FIG. 14, in the optical scanning device having two light sources at the same height, the flare beam emitted from one light source passes through the vicinity of the reflecting mirror and reaches the surface of the photosensitive member. Described the problem caused by. However, it is not limited to the optical scanning device having a plurality of light sources at the same height that the flare rays pass through the vicinity of the reflecting mirror. Even if the light source has one light source at the same height, it cannot prevent the flare light from passing through the vicinity of the reflecting mirror due to the installation condition of the shielding member that shields the flare light or the error of the member. Such problems can occur.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a reflecting mirror in the optical path between the light source and the optical polarizer, so that the flare light emitted from the light source passes through the vicinity of the reflecting mirror. By providing an optical scanning apparatus and an image forming apparatus that can suppress the influence of flare light on an image by suppressing the incidence on the scanned surface without entering the optical polarizer. is there.

In order to achieve the above object, the invention of claim 1 is directed to a light source, an optical polarizer for deflecting a light beam emitted from the light source, and a surface to be scanned corresponding to the deflected light beam deflected and scanned by the optical polarizer. An optical scanning apparatus comprising: a scanning optical system that guides and forms an image; and a reflecting mirror that folds the light emitted from the light source and reflects the reflected light toward the optical polarizer, extending from the reflecting surface of the reflecting mirror A shielding member that shields light is provided at the position.
According to a second aspect of the present invention, in the optical scanning device according to the first aspect, the light source includes a plurality of light sources, and the light beams emitted from the light sources are emitted from other light sources before reaching the scanned surface. It is characterized by intersecting.
According to a third aspect of the present invention, there is provided the optical scanning device according to the first aspect, further comprising a fixing member that fixes the reflecting mirror to the apparatus main body, and the shielding member is formed integrally with the fixing member. To do.
According to a fourth aspect of the invention, there is provided the optical scanning device according to the first, second, or third aspect, wherein the reflected light of the light beam incident on the shielding member is disposed so as to reach a place other than the light source. It is what.
According to a fifth aspect of the present invention, in the optical scanning device according to the first, second, third, or fourth aspect, the shielding member includes the deflected light beam in which the light beam emitted from the light source is deflected by the light polarizer. The shielding member is arranged so that a portion that does not contribute to image formation is shielded and the reflected light incident on the shielding member reaches the outside of the image area in the main scanning direction on the scanned surface. It is characterized by this.
According to a sixth aspect of the present invention, in the optical scanning device according to the first, second, third, fourth, or fifth aspect, the shielding member includes the deflected light beam in which the light beam emitted from the light source is deflected by the optical polarizer. Of the shielding member is shielded, and the angle of the shielding member is set so that the reflected light incident on the shielding member reaches the outside of the image area in the sub-scanning direction on the scanned surface. It is characterized by being attached.
The invention according to claim 7 is the optical scanning device according to claim 1, wherein the shielding member is subjected to antireflection coating or antireflection processing. Is.
The invention according to claim 8 is the optical scanning device according to claim 1, 2, 3, 4, 5, 6 or 7, wherein the shielding member is used to form an image out of the light beam from the light source or the deflected light beam. The low-reflectance body is attached to a place including a place where a non-contributing part is irradiated.
According to a ninth aspect of the invention, a latent image is formed on the surface of the latent image carrier by irradiating the surface of the latent image carrier with a light beam using a light scanning means, and the latent image is developed. In an image forming apparatus for forming an image by finally transferring an obtained image onto a recording material, the optical scanning unit according to claim 1, 2, 3, 4, 5, 6, 7 or 8 as the optical scanning unit. An apparatus is used.

  According to the first to ninth aspects of the present invention, a flare beam emitted from the light source is prevented from passing near the reflecting mirror by providing a shielding member that shields light at a position extending from the reflecting surface of the reflecting mirror. Therefore, the flare beam can be prevented from entering the scanned surface without entering the optical polarizer. Thereby, there exists an outstanding effect that the influence on the image by a flare light can be suppressed.

Hereinafter, an embodiment in which the present invention is applied to an image forming apparatus will be described. First, the configuration and operation of the image forming apparatus according to the present embodiment will be described.
FIG. 1 is an overall schematic configuration diagram of an image forming apparatus (hereinafter referred to as a printer 500) according to the present embodiment. The printer 500 is a tandem intermediate transfer type electrophotographic apparatus, and includes a main body 100 and a paper feed table on which the main body 100 is placed. Note that subscripts Y, M, C, and K in the drawing indicate yellow, cyan, magenta, and black (black), respectively.

  The main body 100 includes an endless belt-shaped intermediate transfer belt 99 near the center. The intermediate transfer belt 99 is wound around a plurality of support rollers and can be rotated and conveyed clockwise in FIG. In FIG. 1, a cleaning device 17 for the intermediate transfer belt is provided on the left side of the support roller 19. The cleaning device 17 removes residual toner remaining on the intermediate transfer belt 99 after image transfer.

  On the intermediate transfer belt 99 stretched between the support roller 14 and the support roller 15, four image forming units 18Y, 18M, and 18C as yellow, cyan, magenta, and black image forming units are arranged along the conveyance direction. , 18K (hereinafter abbreviated as 18Y, M, C, K) are arranged side by side to constitute the tandem image forming unit 20. On the tandem image forming unit 20, a writing device 55 as an optical scanning device as an exposure device is provided as shown in FIG. The printer 100 includes two writing devices 55 for the four image forming units 18, and one writing device 55 irradiates the two photosensitive members 40 with exposure light to form a latent image. .

Each image forming unit 18 of the tandem image forming unit 20 includes drum-shaped photoconductors 40Y, 40M, 40C, and 40K as image carriers that carry toner images of yellow, cyan, magenta, and black. Further, each image forming unit 18 is formed around the photoreceptors 40Y, M, C, K on the photoreceptors 40Y, M, C, K by the charging devices 43Y, M, C, K, and the writing device 55. Developing devices 41Y, 41M, 41C, and 42K that develop the latent image, and a photoconductor cleaning device 42Y that cleans the surfaces of the photoconductors 40Y, 40M, 40C, and 40K after the image is transferred onto the intermediate transfer belt 99. M, C, K, etc. are provided.
Further, at the primary transfer position where the toner image is transferred from the photoconductors 40Y, M, C, K to the intermediate transfer belt 99, the photoconductors 40Y, M, C, K are opposed to each other with the intermediate transfer belt 99 interposed therebetween. As described above, primary transfer rollers 62Y, 62M, 62C, and 62K are provided as components of the primary transfer unit. The support roller 14 is a drive roller that rotationally drives the intermediate transfer belt. When a black monochrome image is formed on the intermediate transfer belt 99, the support rollers 15 and 15 ′, which are not driving rollers, are moved to separate the yellow, cyan, and magenta photoreceptors 40Y, M, and C from the intermediate transfer belt. It is also possible.

  The main body 100 includes a secondary transfer device 22 on the side opposite to the tandem image forming unit 20 with the intermediate transfer belt 99 interposed therebetween. In the example shown in FIG. 1, the secondary transfer device 22 forms a secondary transfer portion by pressing the secondary transfer roller 16 ′ against the secondary transfer counter roller 16, and the secondary transfer counter roller 16 and the secondary transfer roller 16 are secondary-transferred. By applying a transfer electric field to the roller 16 ', the image on the intermediate transfer belt 99 is transferred to a sheet S as transfer paper. Further, the main body 100 is provided with a fixing device 25 that fixes the transferred image on the sheet S beside the secondary transfer device 22 (left side in FIG. 1). Further, between the secondary transfer device 22 and the fixing device 25, a conveyance belt 24 that conveys the sheet S, on which the image on the intermediate transfer belt 99 has been transferred by the secondary transfer device 22, to the fixing device 25 is provided. Yes. The fixing device 25 is configured by pressing a pressure roller 27 against a fixing belt 26 that is an endless belt. The sheet S after the image transfer is conveyed to the fixing device 25 by the conveyance belt 24. In the example shown in FIG. 1, sheet reversal is performed under the secondary transfer device 22 and the fixing device 25 so as to invert the sheet S so as to record images on both sides of the sheet S in parallel with the tandem image forming unit 20 described above. A device 28 is provided.

  When image data is sent to the printer 100 and an image forming start signal is received, the support roller 14 is driven to rotate by a drive motor (not shown), and the other plurality of support rollers are driven to rotate the intermediate transfer belt 99. Move endlessly. At the same time, latent images corresponding to yellow, cyan, magenta, and black are written on the respective photoreceptors 40 by the individual image forming units 18 by the writing device 55, and each developing device 41 included in each image forming unit 18 is provided. By developing the latent image, a single color image of yellow, cyan, magenta, and black is formed on each photoconductor 40, respectively. Then, along with the endless movement of the intermediate transfer belt 99, those single-color images are sequentially transferred to the intermediate transfer belt 99 at the primary transfer portion that is the opposing portion of each photoconductor 40 and each primary transfer roller 62, To form a color image.

In addition, one of the paper feed rollers 42 of the paper feed table 200 is selectively rotated to feed out the sheet S from one of the paper feed cassettes 44 provided in the paper bank 43 in multiple stages, and separated and fed one by one by the separation roller 45. The paper is put into the paper path 46, transported by the transport roller 47, guided to the main body side paper feed path 48 in the copying machine main body 100, and abutted against the registration roller 49 and stopped. Alternatively, the manual feed roller 50 is rotated to feed out the sheets S on the manual feed tray 51, separated one by one by the manual feed separation roller 52, put into the manual feed path 53, and abutted against the registration roller 49 and stopped. Then, the registration roller 49 is rotated in synchronization with the color image on the intermediate transfer belt 99, and the sheet S is fed between the secondary transfer roller 16 ′ of the secondary transfer device 22 and the intermediate transfer belt 99, and the intermediate transfer is performed. The color image on the belt 99 is transferred onto the sheet S by the secondary transfer device 22 and the color image is recorded on the sheet S. The sheet S after the image transfer is transported by the transport belt 24 and sent to the fixing device 25, and heat and pressure are applied to the fixing device 25 to fix the color image on the sheet S. The sheet is discharged outside and stacked on the sheet discharge tray 57.
When performing double-sided printing, the sheet S that has been switched by a switching claw (not shown) and passed through the fixing device 25 is placed in the sheet reversing device 28, where it is reversed and guided again to the transfer position, and an image is recorded on the back surface. After that, the paper is discharged onto a paper discharge tray 57 by a discharge roller 56. On the other hand, the residual toner remaining on the surface of the intermediate transfer belt 99 after the image transfer is removed by the belt cleaning device 17 to prepare for the image formation by the tandem image forming unit 20 again.

Next, the writing device 55 that is a characteristic part of the present embodiment will be described.
2 is a plan view of the writing device 55 as viewed from above, and FIG. 3 is a cross-sectional view of the writing device 55 as viewed from the side.
As shown in FIG. 2, the writing device 55 irradiates the two photosensitive members 40 with exposure light from one writing device 55 as shown in FIG. 1, and uses an optical system other than the polygon mirror 9. Prepare two each.
The writing device 55 includes an LD unit 3 as a light source unit in which a plurality of light sources are housed in a container. The LD unit 3 includes two light sources (first LD 1a and second LD 1b) in a height direction (first LD 1a and second LD 1b). Four sets are arranged in the front-back direction in FIG. 2 and include a total of eight light sources.
Light rays emitted from the first LD 1a and the second LD 1b as the light source pass through the first collimator lens 2a and the second collimator lens 2b, respectively, and are emitted from the LD unit 3 as the first principal ray 4a and the second principal ray 4b. To do. The first principal ray 4 a and the second principal ray 4 b each pass through the aperture 5, pass through the cylindrical lens 6, are reflected by the folding mirror 7 that is a reflecting mirror, and enter the polygon mirror 9. The polygon mirror 9 which is a polarizer is rotated by a polygon motor 10, and the first principal ray 4 a and the second principal ray 4 b contributing to image formation are incident on the rotating polygon mirror 9 and reflected, thereby scanning light SL. And the sync ray BDL. In the writing device 55, the front-back direction of the paper surface in FIG. 3 is the height direction, and the first LD 1a and the second LD 1b are arranged at the same height. The first principal ray 4a and the second principal ray 4b travel on the same optical path until they enter the polygon mirror 9.
The scanning light beam SL is transmitted through the Fθ lens 12, is then folded back by the upper mirror 31 and the lower mirror 32, is transmitted through the lower Fθ lens 12, and is reflected by the second lower mirror 33. The light is emitted from the window portion 60 provided in the casing 55 toward the photoconductor 40. The scanning light beam SL emitted from the writing device 55 reaches the surface of the photoconductor 40 that is the surface to be scanned and forms a latent image.
Further, after reaching the synchronization detection plate 11, the sync beam BDL is converted into a signal and used for controlling the light emission timing of the first LD 1a and the second LD 1b. Here, the folding mirror 7 is fixed to an optical housing (not shown) by a leaf spring 8 which is a fixing member.

  FIG. 4 is an enlarged explanatory view of the vicinity of the left folding mirror 7 in FIG. FIG. 5 is a perspective view of the leaf spring 8, and is a perspective view of the leaf spring 8 viewed from angles different from (a), (b), and (c). FIG. 6 is a three-side view illustrating a state in which the folding mirror 7 is fixed to the optical housing by the leaf spring 8. FIG. 6A is a top view as seen from the direction of arrow A in FIG. 5A, with the leaf spring 8 shown in FIG. 5A fixed to the bottom surface 55b of the optical housing with a screw 81. FIG. FIG. 6B is a front view seen from the direction of arrow B in FIG. 5A, and FIG. 6C is a side view seen from the direction of arrow C in FIG. As shown in FIG. 6, the folding mirror 7 is fixed to the optical housing by being sandwiched between a leaf spring 8 fixed to the bottom surface 55b by a screw 81 and two housing ribs 55a extending upward from the bottom surface 55b. .

  As shown in FIGS. 4, 5, and 6, the writing device 55 of the present embodiment has a shape that extends laterally from a lateral surface to a leaf spring 8 that is a fixing member that fixes the folding mirror 7. Three shielding plates 66 are integrally formed. The plate spring 8 is a general plate spring and is a thin metal body having a thickness of 0.1 [mm] to 0.5 [mm], and is disposed with extremely high accuracy with respect to the LD unit 3 and other optical components. This is a fixing member for the folding mirror 7. For this reason, if it is the structure provided with the 3rd shielding board 66 integrally formed with the leaf | plate spring 8, it is set as the structure which is not provided with the 3rd shielding board 66 by producing the component precision of the leaf | plate spring 8 with high precision. The third shielding plate 66 for shielding the photoreceptor arrival flare MFL can be arranged with high accuracy without much cost increase. Therefore, as shown in FIG. 2 and FIG. 4, while preventing a part of the third flare light beam FLb3 from being blocked in a limited space and becoming a photoreceptor arrival flare MFL (broken line in FIG. 6). The leaf spring 8 can be arranged at a limit position that does not block the first principal ray 4a, the second principal ray 4b, the scanning ray SL, and the synchronization ray BDL.

In the conventional writing device 55 described with reference to FIG. 14, it is desirable to shield the flare light on the light source side from the position where the first principal ray 4 a and the second principal ray 4 b intersect. It is difficult to arrange a fixing member or the like. In particular, as in the writing device 55 of the present embodiment and the conventional writing device 55 shown in FIG. 14, when the angles of the respective rays in the same plane are small, the first principal ray 4a and the second principal ray 4b are changed. It is difficult to completely shield the photoreceptor arrival flare MFL by providing a shielding member without a gap without blocking.
Further, as shown in FIG. 14, the lateral region α of the folding mirror 7 through which the photoreceptor arrival flare MFL passes is the folding mirror 7 and the first principal ray 4a and the second principal ray 4b reflected by the folding mirror 7. The first principal ray 4a and the second principal ray 4b reflected by the polygon mirror 9 and deflected, the scanning ray SL and the synchronization ray BDL, the fixing member (not shown) of the first Fθ lens 12, and the folding. It is a position surrounded by a leaf spring 8 that is a fixing member of the mirror 7. For this reason, it is difficult in terms of space to arrange a member for shielding the photoreceptor arrival flare MFL on an optical housing (not shown). For example, if an attempt is made to form a rib on the optical housing as a light shielding member in the region α, it is necessary to form a thin and long rib because it is a narrow region. If the optical housing is made by aluminum die casting, there is a possibility that the material does not flow into the rib portion of the die even if a die that forms a thin and long rib is created as the casting condition of aluminum die casting. For this reason, manufacturing defects are likely to occur. Also, when the optical housing is made of resin, it is easier to manufacture than aluminum die-casting, but the thin and long ribs made of resin are uneasy in terms of strength and can be damaged by long-term use, causing the flare to reach the photoreceptor. There is a risk that the MFL cannot be shielded. In addition, since an optical housing made of resin may be deformed by a temperature rise, it is preferable to use an aluminum die cast for a high-speed model. For this reason, it is difficult to set up a rib that shields the photoreceptor arrival flare MFL in the region α. Moreover, although the method of producing a rib as another member and fixing on an optical housing can be considered, there exists a problem that a number of parts increases.
On the other hand, in the writing device 55 of the present embodiment, the third shielding plate 66 as the shielding member is provided integrally with the leaf spring 8 which is the fixing member of the folding mirror 7, so that the number of parts is increased. In addition, there is no difficulty of forming a rib in a narrow area, and the photoreceptor arrival flare MFL can be easily shielded.

Further, the problem that the photoreceptor arrival flare MFL passes through the vicinity of the folding mirror 7 as described with reference to FIG. 14 is likely to occur because a plurality of light sources are provided at the same height as shown in FIG. This is because, in order to provide a space through which the principal ray of light emitted from one light source passes, a space through which a flare ray of light emitted from another light source passes is created. If there is only one light source, both sides of the space may be sandwiched by ribs, leaving a space through which the principal ray of light emitted from the light source passes. In the configuration shown in FIG. 14, the two principal rays emitted from the two light sources intersect each other on the surface of the polygon mirror 9, so that the optical axes of the two principal rays gradually increase in the previous region. Therefore, it is difficult to provide a shielding member therebetween.
Patent Document 3 describes diffused light reflected by an LD monitor, and does not mention flare light caused by internal reflection of the LD unit 3. Further, although there is a description that it is easy to arrange the shielding member conceptually, it is difficult to arrange the shielding member due to the recent need for downsizing of the optical scanning device and the image forming apparatus.
On the other hand, in the writing device 55 of this embodiment, as shown in FIGS. 4 and 6A, a third shielding plate 66 that shields light is provided at a position extended from the reflecting surface of the folding mirror 7. Therefore, since it is not necessary to provide a shielding member between the optical axes of the two principal rays, the photosensitive member arrival flare MFL which attempts to pass near the folding mirror 7 is shielded without shielding other principal rays. can do.
As described above, in the writing device 55 according to the present embodiment, the photosensitive member arrival flare MFL that is about to pass through the vicinity of the folding mirror 7 can be reliably shielded, so that the second LD 1b is on the photosensitive member 40 during light emission. It can prevent that a specific location is always exposed. For this reason, it is possible to prevent black streaks and black bands extending in the sub-scanning direction of the image.

Further, in the writing device 55 of the present embodiment, the third shielding plate 66 as a shielding member that shields the photoreceptor arrival flare MFL that attempts to pass in the vicinity of the folding mirror 7 is provided on the plate spring 8 that is a fixing member of the folding mirror 7. Although it is provided integrally, the shielding member for shielding the photoreceptor arrival flare MFL is not limited to this. For example, a light shielding member may be attached to the folding mirror 7 like a mylar 66b indicated by a broken line in FIG. The member that shields the photosensitive member arrival flare MFL and is attached to the folding mirror 7 is not limited to the mylar, and the position to be attached is not limited to the folding mirror 7, and the leaf spring 8, the housing rib 55 a, and the like are folded. Any member in the vicinity of the mirror 7 may be used.
Note that the configuration in which the mylar 66b is attached may cause problems such as an increase in the number of parts, a reduction in attachment accuracy, and peeling of the attachment portion during use. A structure that is formed manually is more preferable.

  The first LD 1a and the second LD 1b, which are light sources, measure the amount of emitted light with an internal monitor in order to control the amount of emitted light (APC: Auto Power Control). When the reflected light 19 of the photosensitive member arrival flare generated by the reflection of the photosensitive member arrival flare MFL by the leaf spring 8 reaches the internal monitor of the LD, an erroneous detection of the internal monitor causes a decrease in the amount of emitted light and causes image deterioration. Sometimes. Therefore, it is desirable to set the angle of the leaf spring 8 so that the light beam reflected by the leaf spring 8 does not reach the first LD 1a and the second LD 1b.

7 shows that the light beam emitted from the light source (the first LD 1a and the second LD 1b) of the right LD unit 3 in FIG. 2 out of the two LD units 3 shown in FIG. 9 is a top view schematically showing a state in which the surface of the photoconductor 40 is irradiated via 9. As shown in FIG. 7, the second principal ray 4b emitted from the second LD 1b is reflected by the edge surface of the second collimator lens 2b, and can become a photoreceptor arrival flare MFL.
Further, as shown in FIG. 7, the APC light beam 29 emitted during the measurement and control of the emitted light quantity and incident on the polygon mirror 9 is scanned by the polarizer, and the outside of the scanning light beam SL and the synchronizing light beam BDL becomes the scanning APC light beam 30. . The reflected light generated by the scanning APC light beam 30 reflected on the back surface of the third shielding plate 66 of the leaf spring 8 (the back surface with respect to the surface shielding the photoconductor arrival flare MFL) reaches the photoconductor 40 and causes image degradation. Sometimes.

  Therefore, in the third shield plate 66 of the leaf spring 8, the configuration and shape of the portion where the scanning APC light beam 30 strikes and the surface in the vicinity thereof is the direction in which the scanning APC light beam 30 is reflected, i. It is desirable that the image area of the photoreceptor 40 be outside the main scanning direction, or be blocked by an optical housing or other member (not shown) in the sub scanning direction.

First, a configuration in which the direction of the reflected light is shifted in the main scanning direction so that the reflected light of the light beam incident on the third shielding plate 66 does not enter the image area of the light source or the photoreceptor 40 will be described.
FIG. 8 is a top view schematically showing a state in which the reflected light of the light incident on the third shielding plate 66 enters the image area of the light source or the photoreceptor 40. The surface of the third shielding plate 66 shown in FIG. 8 is disposed substantially perpendicular to the incident direction of the photoreceptor arrival flare MFL. With this arrangement, the reflected light travels so as to be reflected in the same direction as the direction in which the photoconductor arrival flare MFL is incident and to travel in a direction substantially the same as the path through which the photoconductor arrival flare MFL has passed. The photoreceptor reaching flare MFL incident on the surface of the three shielding plates 66 may reach the second LD 1b. Further, since the incident angle β of the scanning APC light beam 30 with respect to the back surface of the third shielding plate 66 is small, the APC reflected light 34 which is reflected light is arranged so as to prevent the light beam entering the image area of the photoconductor 40. In addition, the light does not enter the fourth shielding member 78 and may enter the image area of the photoreceptor 40.

FIG. 9 schematically shows a state in which the direction of the reflected light is shifted in the main scanning direction so that the reflected light of the light incident on the third shielding plate 66 does not enter the image area of the light source or the photoreceptor 40. It is a top view.
As shown in FIG. 9, by arranging the third shielding plate 66 so that the perpendicular line 75 of the surface of the third shielding plate 66 and the photoreceptor arrival flare MFL have an angle, the reflected light of the photoreceptor arrival flare MFL is reflected. The photosensitive member arrival flare MFL is reflected in a direction different from the incident direction. Specifically, as shown in FIG. 6A, the direction of reflection by the third shielding plate 66 of the third flare light beam FLb3 that does not contribute to image formation among the light beams emitted from the second LD 1b is the third shielding plate. The direction of incidence of the third flare light beam FLb3 on 66 is different. As a result, the reflected light travels along a path different from the path through which the photoreceptor arrival flare MFL has passed, so that the reflected light of the photoreceptor arrival flare MFL incident on the surface of the third shielding plate 66 reaches the second LD 1b. Can be prevented. Thereby, it is possible to prevent the amount of emitted light from being reduced due to erroneous detection of the internal monitor of the light source, and it is possible to prevent image deterioration due to erroneous detection of the internal monitor.
In the configuration shown in FIG. 9, the incident angle β of the scanning APC light beam 30 with respect to the back surface of the third shielding plate 66 is larger than that shown in FIG. 8. For this reason, the APC reflected light 34 which is the reflected light of the scanning APC light beam 30 enters the fourth shielding member 78 disposed outside the region through which the light beam incident on the image region of the photoconductor 40 passes, and the APC reflected light. 34 can be prevented from entering the image area of the photoreceptor 40. Thereby, it is possible to prevent image deterioration caused by the APC reflected light 34 that is the reflected light of the scanning APC light beam 30 reaching the photoconductor 40.

Next, a configuration in which the direction of the reflected light is shifted in the sub-scanning direction so that the reflected light of the light beam incident on the third shielding plate 66 does not enter the image area of the light source or the photoreceptor 40 will be described.
FIG. 10 schematically shows a state in which the direction of the reflected light is shifted in the main scanning direction so that the reflected light of the light incident on the third shielding plate 66 does not enter the image area of the light source or the photoreceptor 40. It is a side view.
As shown in FIG. 10, the third shielding plate 66 of the leaf spring 8 is provided with an angle in the sub-scanning direction, and the surface of the third shielding plate 66 is installed so as to have an elevation angle or depression angle with respect to the incident light. Thus, even if the photoreceptor arrival flare MFL is reflected by the third shielding plate 66 of the leaf spring 8, the flare reflected light 19 of the photoreceptor arrival flare is different from the first LD 1a and the second LD 1b in the sub-scanning direction (height direction). ), The flare reflected light 19 can escape to a position where it does not reach the first LD 1a and the second LD 1b and the monitor inside thereof.

It has already been described that the second principal ray 4b emitted from the second LD 1b can be reflected by the edge surface of the second collimator lens 2b and become a photoreceptor arrival flare MFL. Here, the normal to the plane of the third shield plate 66 which is part of the leaf spring 8 to the perpendicular 75, the perpendicular 75 and the photosensitive member reaches flare MFL is to the angle first angle theta ₁ which forms in the sub-scanning direction. Angle which the reflected light 19 of the photosensitive member reaches flare MFL and the photosensitive member reaches flare MFL forms in the sub-scanning direction is a second angle 2 [Theta] _1. The writing device 55 of the present embodiment includes a fifth shielding plate 76 on the light source side with respect to the third shielding plate 66, and the distance in the sub-scanning direction of the fifth shielding plate 76 from the photoreceptor arrival flare MFL is the first distance. Θ ₁ is set so as to satisfy the following expression (1), where X ₁ is the light beam traveling direction distance between the third shielding plate 66 and the fifth shielding plate 76 is the first length L _1. Is desirable.
L ₁ × SIN2θ ₁ > X ₁ (1)
By setting in this way, it is possible to prevent the reflected light of the photoreceptor arrival flare MFL incident on the surface of the third shielding plate 66 from reaching the second LD 1b. Therefore, it is possible to prevent the amount of emitted light from being reduced due to erroneous detection of the internal monitor of the light source, and to prevent image deterioration due to erroneous detection of the internal monitor.
In FIG. 10, the photoreceptor arrival flare MFL, the first principal ray 4a, and the second principal ray 4b pass through the same plane in the sub-scanning direction, but do not have to pass through the same plane. The fifth shielding plate 76 may be a part of the optical housing, a part of the LD unit 3, or a part of the aperture 5.

In addition, the APC light beam 29 emitted from the first LD 1a and the second LD 1b at the time of APC passes through the same position as the first main light beam 4a and the second main light beam 4b, and is incident on the polygon motor 10 and deflected. Here, the normal to the plane of the third shield plate 66 which is part of the leaf spring 8 to the perpendicular 75, the perpendicular 75 to the scanning APC beam 30 is to angle the third angle theta ₂ which forms in the sub-scanning direction. Angle APC reflected light 34 and the scanning APC beam 30 which is reflected light of the scanning APC light forms in the sub-scanning direction is the fourth angle 2 [Theta] _2. The writing device 55 according to the present embodiment includes a sixth shielding plate 77 on the photosensitive member 40 side with respect to the third shielding plate 66, and the APC reflected light 34, which is a reflected light of the scanning APC light beam, is applied to the sixth shielding plate 77. the sub-scanning direction between the second distance X _2, when the third shield plate 66 the light ray traveling direction between the sixth shielding plate 77 and the second length L _2, the following equation (2) it is desirable to set the theta ₂ to satisfy.
L ₂ × SIN2θ ₂ > X ₂
By setting in this way, the APC reflected light 34 that is the reflected light of the scanning APC light beam 30 is incident on the sixth shielding plate 77, and the APC reflected light 34 is prevented from entering the image area of the photoreceptor 40. Can do. Thereby, it is possible to prevent image deterioration caused by the APC reflected light 34 that is the reflected light of the scanning APC light beam 30 reaching the photoconductor 40.
Is a 10 in θ ₁ = θ _2, may not be θ ₁ = θ _2. The sixth shielding plate 77 may be a part of an optical housing or a part of an optical element fixing member (not shown).

  Further, the third shielding plate 66 of the leaf spring 8 may be subjected to antireflection processing such as antireflection coating or roughening the surface. By taking such anti-reflection processing, if a means for suppressing the generation of secondary diffused light / reflected light (flare light) due to the provision of the third shielding plate 66 is taken, the third shielding is achieved. It is possible to prevent the generation of further flare light due to the reflected light from the plate 66. The antireflection processing is not limited to the third shielding plate 66 but may be applied to other portions of the leaf spring 8.

  Further, as a means for suppressing the generation of secondary diffused light / reflected light (flare light) resulting from the provision of the third shielding plate 66, a plate subjected to antireflection processing such as antireflection coating or roughening the surface. Alternatively, a low reflectivity body such as another member may be attached to the third shielding plate 66 of the leaf spring 8. FIG. 11 is a perspective explanatory view of the leaf spring 8 in which the low reflectivity body 66 a is attached to the third shielding plate 66. As the low reflectivity body 66a, an antireflection member such as cinnamon paper may be attached.

The third shielding plate 66 may have a shape in which the angle in the sub-scanning direction is different between the front surface and the back surface. FIG. 12 is an explanatory perspective view of the leaf spring 8 including the third shielding plate 66 having different angles in the sub-scanning direction on the front surface and the back surface.
By using the leaf spring 8 including the third shielding plate 66 having a shape as shown in FIG. 12, it is possible to realize a configuration where θ ₁ = θ ₂ as described with reference to FIG.

  FIG. 13 shows a light emission timing example of the first LD 1a and the second LD 1b. APC is performed at a timing different from the timing at which the synchronization light beam BDL and the scanning light beam SL, which are light beams contributing to image formation, scan. The light beam that has been emitted and scanned based on the signal of the synchronized light beam emission signal 57 shown in FIG. 13 is the synchronized light beam BDL, and the light beam that has been scanned based on the signal of the scanned light beam signal 58 is scanned. The broken light beam is the scanning light beam SL. A scanning APC light beam 30 is a light beam that is emitted based on the APC light emission signal 59 and subjected to a signal of the emitted light beam.

  When a semiconductor laser array (hereinafter referred to as LDA) capable of emitting a plurality of light beams from one LD is used as a light source, it is necessary to sequentially perform APC for each light beam, and the APC execution time emits a single light beam. The time required for the APC light emission signal 59 is increased, and the area of the scanning APC light is widened, so that the scanning reflected on the third shielding plate 66 which is a part of the leaf spring 8 is inevitably made. The reflected light of the APC light beam is likely to be generated, and image deterioration due to flare can be easily caused. With respect to such a problem, the configuration in which the low-reflectance body 66a is attached to the third shielding plate 66 described with reference to FIG. 11 and the front and back surfaces of the third shielding plate 66 described with reference to FIG. By applying the configuration in which the angle in the sub-scanning direction is different, it is possible to prevent image degradation due to flare caused by the reflected light of the scanning APC light beam. Note that the case where a plurality of LDs are used is not limited to the case where LDAs are used, and the same applies to the case where a light source unit using a plurality of LDAs is used.

  The present invention is not limited to the above embodiment. That is, various modifications can be made without departing from the scope of the present invention.

  As described above, according to the present embodiment, the writing device 55 that is an optical scanning device includes the first LD 1a and the second LD 1b that are light sources, and the optical polarizer that deflects the light beams emitted from the first LD 1a and the second LD 1b. The polygon mirror 9 is provided. The writing device 55 is a scanning optical system that guides the scanning light beam SL and the synchronizing light beam BDL deflected and scanned by the polygon mirror 9 onto the surface of the photosensitive member 40 corresponding to the scanning surface and forms an image. A plurality of Fθ lenses 12 are provided. The writing device 55 includes a folding mirror 7 which is a reflecting mirror that folds the light beams emitted from the first LD 1 a and the second LD 1 b and reflects them toward the polygon mirror 9. The writing device 55 includes a third shielding plate 66 that is a shielding member that shields light at a position extended from the reflection surface of the folding mirror 7. By providing the third shielding plate 66, it is possible to prevent the flare rays emitted from the first LD 1a and the second LD 1b, which are light sources, from passing through the region α in the vicinity of the folding mirror 7, and the flare rays are polygons. It is possible to suppress the incidence on the surface of the photoreceptor 40 without entering the mirror 9. Thereby, the influence on the image by a flare light can be suppressed.

  The writing device 55 includes two light sources, the first LD 1a and the second LD 1b, and the light emitted from one of the light sources intersects with the light emitted from the other light source before reaching the surface of the photoreceptor 40. . If the two light beams intersect with each other in this way, the optical axes of the two principal light beams gradually narrow before the crossing, and it is difficult to provide a shielding member between them. For this reason, in order to provide a space for passing the principal ray of the light emitted from one light source, a space through which the flare light of the light emitted from the other light source passes is created, and the photoreceptor arrival flare MFL becomes the photoreceptor. 40 was reached. On the other hand, in the writing device 55 of the present embodiment, the third shielding plate 66 is provided on the side of the folding mirror 7, so that it is not necessary to provide a shielding member between the two light beams. In addition, it is possible to prevent the photoreceptor arrival flare MFL from reaching the photoreceptor 40.

  By forming the third shielding plate 66 integrally with the leaf spring 8 which is a fixing member for fixing the folding mirror 7 to the writing device 55 main body, an increase in the number of parts can be prevented and high accuracy can be achieved. Three shielding plates 66 can be installed.

  Further, as described with reference to FIGS. 9 and 10, the reflected light of the photoreceptor arrival flare MFL, which is a light beam incident on the third shielding plate 66, reaches a place other than the first LD 1a and the second LD 1b which are light sources. By arranging in such a manner, it is possible to prevent a decrease in the amount of emitted light due to erroneous detection of the internal monitor of the light source, and it is possible to prevent image deterioration due to erroneous detection of the internal monitor.

  In addition, as described with reference to FIG. 9, the third shielding plate 66 is a portion that does not contribute to image formation among the deflected light beams in which the light beams emitted from the first LD 1 a and the second LD 1 b are deflected by the polygon mirror 9. APC reflected light 34, which is reflected light of the scanning light APC 30 incident on the third shielding plate 66 among the deflected light, is applied to the fourth shielding member 78 outside the image area in the main scanning direction on the surface of the photoreceptor 40. A third shielding plate 66 is arranged so as to reach. Thereby, it is possible to prevent the APC reflected light 34 from entering the image area of the photoconductor 40, and it is possible to prevent image deterioration caused by the APC reflected light 34 reaching the photoconductor 40.

  Further, as described with reference to FIG. 10, the third shielding plate 66 is a portion that does not contribute to image formation among the deflected light beams in which the light beams emitted from the first LD 1 a and the second LD 1 b are deflected by the polygon mirror 9. APC reflected light 34, which is a reflected light of the scanning APC light 30 incident on the third shielding plate 66 among the deflected light, is applied to the sixth shielding plate 77 outside the image area in the sub-scanning direction on the surface of the photoconductor 40. You may angle the 3rd shielding board 66 so that it may reach | attain. Thereby, it is possible to prevent the APC reflected light 34 from entering the image area of the photoconductor 40, and it is possible to prevent image deterioration caused by the APC reflected light 34 reaching the photoconductor 40.

  In addition, the surface of the third shielding plate 66 is subjected to antireflection coating or antireflection processing, thereby preventing the generation of secondary diffused light / reflected light (flare light) due to the provision of the third shielding plate 66. can do.

  In addition, as shown in FIG. 11, the low-reflectance body 66 a may be attached to a place including a place where a portion that does not contribute to image formation is irradiated among light rays or deflected light rays from the light source of the third shielding plate 66. . Thereby, generation | occurrence | production of the secondary diffused light and reflected light (flare light) resulting from providing the 3rd shielding board 66 can be prevented.

  In addition, the printer 100 that is an image forming apparatus including the writing device 55 as an optical scanning unit can suppress the influence of flare light on the image, and can perform good image formation.

1 is a schematic configuration diagram of a printer according to an embodiment. The top view which looked at the writing device of this embodiment from the upper part. Sectional drawing which looked at the writing apparatus of this embodiment from the side. FIG. 4 is an enlarged explanatory view in the vicinity of a folding mirror. The perspective view of a leaf | plate spring. FIG. 3 is a three-view diagram illustrating a state in which a folding mirror is fixed to an optical housing by a leaf spring, (a) is a top view, (b) is a front view, and (c) is a side view. FIG. 3 is a top view schematically showing a state in which a light beam emitted from a light source is applied to the surface of a photoreceptor. The top view which showed typically the state in which the reflected light of the light ray which injected into the 3rd shielding member injects into the image area of a light source or a photoreceptor. The top view which showed typically the state which shifted the direction of reflected light to the main scanning direction so that the reflected light of the light ray which injected into the 3rd shielding member may not enter into the image area | region of a light source or a photoreceptor. The side view which showed typically the state which shifted the direction of reflected light to the subscanning direction so that the reflected light of the light ray which injected into the 3rd shielding member may not enter into the image area | region of a light source or a photoreceptor. The perspective explanatory drawing of the leaf | plate spring which affixed the low reflectance body on the 3rd shielding member. The perspective explanatory view of a leaf spring provided with the 3rd shielding member from which the angle of a subscanning direction differs in the surface and the back. The figure which shows the example of light emission timing of 1st LD and 2nd LD. The block diagram which shows an example of the conventional optical scanning device.

Explanation of symbols

1a 1st LD
1b 2nd LD
2a first collimator lens 2b second collimator lens 3 LD unit 4a first principal ray 4b second principal ray 5 aperture 6 cylindrical lens 7 folding mirror 8 leaf spring 9 polygon mirror 10 polygon motor 11 synchronization detection plate 12 Fθ lens 29 APC ray 30 Scanning APC Beam 31 Upper Mirror 32 Lower Mirror 33 Second Lower Mirror 34 APC Reflected Light 40 Photoconductor 55 Writing Device 55a Housing Rib 55b Bottom 60 Window 64 First Shielding Plate 65 Second Shielding Plate 66 Third Shielding Plate 66a Low-reflectance body 66b Mylar 75 Perpendicular line 76 Fifth shield plate 77 Sixth shield plate 78 Fourth shield member 81 Screw BDL Sync beam FLa1 First flare beam FLa2 Second flare beam FLb3 Third flare beam FLb4 Fourth flare beam MFL Photosensitive Body reaching flare SL Scanning ray

Claims (9)

A light source;
An optical polarizer that deflects the light emitted from the light source;
A scanning optical system for directing and deflecting the deflected light beam deflected and scanned by the optical polarizer onto a corresponding scanned surface;
In an optical scanning device comprising a reflecting mirror that folds the light emitted from the light source and reflects it toward the optical polarizer,
An optical scanning device characterized in that a shielding member for shielding light is provided at a position extending from a reflection surface of the reflecting mirror. The optical scanning device according to claim 1.
A plurality of the light sources,
An optical scanning device characterized in that a light beam emitted from the light source intersects with a light beam emitted from another light source before reaching the surface to be scanned. The optical scanning device according to claim 1.
A fixing member for fixing the reflecting mirror to the apparatus body;
An optical scanning device characterized in that the shielding member is formed integrally with the fixing member. The optical scanning device according to claim 1, 2 or 3,
An optical scanning device, wherein the reflected light of the light beam incident on the shielding member is disposed so as to reach a place other than the light source. The optical scanning device according to claim 1, 2, 3 or 4,
The shielding member shields a portion of the deflected light beam that is deflected by the light polarizer from the light source and does not contribute to image formation, and the reflected light incident on the shield member is reflected by the deflected light beam. An optical scanning device characterized in that the shielding member is disposed so as to reach an outside of an image region in the main scanning direction on the surface to be scanned. The optical scanning device according to claim 1, 2, 3, 4 or 5.
The shielding member shields a portion of the deflected light beam that is deflected by the light polarizer from the light source and does not contribute to image formation, and the reflected light incident on the shield member is reflected by the deflected light beam. An optical scanning device characterized in that the shielding member is angled so as to reach outside the image area in the sub-scanning direction on the surface to be scanned. The optical scanning device according to claim 1, 2, 3, 4, 5 or 6.
An optical scanning apparatus, wherein the shielding member is subjected to antireflection coating or antireflection processing. The optical scanning device according to claim 1, 2, 3, 4, 5, 6 or 7.
An optical scanning device according to claim 1, wherein the shielding member has a low-reflectance body attached to a location including a location where a portion of the light beam from the light source or the deflected light beam that does not contribute to image formation is irradiated. A latent image is formed on the surface of the latent image carrier by irradiating light onto the surface of the latent image carrier using an optical scanning means, and an image obtained by developing the latent image is finally recorded on a recording material. In an image forming apparatus that forms an image by transferring it to the top,
An image forming apparatus using the optical scanning device according to claim 1, 2, 3, 4, 5, 6, 7 or 8.

Images