Scanning optical device and image forming apparatus

Abstract

To reduce the size of a scanning optical device configured such that positioning of a plurality of laser supports is performed and subsequently the laser supports are bonded and fixed to an optical box.SOLUTION: A scanning optical device 2 has a plurality of laser supports 112a, 112b that are subjected to positioning and bonded and fixed to an optical box 101. The at least two or more laser supports 112a, 112b are arranged in an arrangement direction (Lc) to be adjacent to each other. The optical box 101 has bonding parts 150a, 150b bonded to the laser supports 112a, 112b. The bonding parts 150a, 150b are arranged in directions (La, Lb) different from the arrangement direction.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a scanning optical device and an image forming device, and is suitable for image forming devices such as copiers and laser beam printers, and in particular to a scanning optical device configured to arrange, adjust, and adhesively fix a plurality of light sources in a color image forming device. [Background technology]

[0002] Conventionally, a scanning optical device used in an image forming apparatus using electrophotography is disclosed, for example, in Patent Document 1. In recent years, there has been a demand for cost reduction and miniaturization of scanning optical devices. For this reason, a scanning optical device has been adopted in which optical components are assembled in an optical box, two laser supports containing light sources are positioned so as to obtain desired optical characteristics, and then the two laser supports are adhesively fixed to the optical box between them. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-121341 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional example has the following problems. By providing an adhesive portion between the laser supports and the optical box between the two laser supports, the distance between the laser supports increases, and as a result, the distance between the light sources that emit laser light also increases. This increases the size of the laser substrate electrically connected to the light source. Furthermore, because the distance between the laser lights incident on the rotating polygon mirror also increases, the incident lens through which the two laser lights pass also increases. Furthermore, the optical box that houses them also increases in size, which could result in an increase in the size of the scanning optical device.

[0005] The present invention was made under these circumstances, and aims to achieve miniaturization of a scanning optical device even in a configuration in which multiple laser supports are adjusted in position and then adhesively fixed to an optical box. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems, the present invention has the following configuration.

[0007] (1) A scanning optical device comprising a plurality of light sources, a plurality of support members each containing a plurality of the light sources, a rotating polygon mirror that deflects and scans the light beams emitted from the light sources, and an optical box that houses the plurality of support members and the rotating polygon mirror, wherein the plurality of support members, the positions of which have been adjusted, are adhesively fixed to the optical box, and wherein at least two or more of the support members are arranged adjacent to each other in an arrangement direction, and the optical box has an adhesive portion that is adhesively bonded to the support members, and the adhesive portion is arranged in a direction different from the arrangement direction.

[0008] (2) A scanning optical device comprising a first light source, a second light source, a first support member containing the first light source, a second support member containing the second light source, a rotating polygon mirror that deflects and scans the light beams emitted from the first light source and the second light source, and an optical box that houses the first support member, the second support member, and the rotating polygon mirror, wherein the first support member and the second support member, whose positions have been adjusted, are adhesively fixed to the optical box, wherein the first support member and the second support member are arranged adjacent to each other in an arrangement direction, and the optical box has a first adhesive portion adhesively bonded to the first support member and a second adhesive portion adhesively bonded to the second support member, and the first adhesive portion and the second adhesive portion are arranged in a direction different from the arrangement direction.

[0009] (3) An image forming apparatus comprising: a scanning optical device according to (1) or (2); a plurality of image carriers scanned with the light beam by the scanning optical device; and a developing means for developing electrostatic latent images formed on the plurality of image carriers. [Effects of the Invention]

[0010] According to the present invention, even in a configuration in which a plurality of laser supports are adhesively fixed to an optical box after their positions are adjusted, it is possible to achieve a reduction in the size of the scanning optical device. [Brief explanation of the drawings]

[0011] [Figure 1] Schematic cross-sectional view showing an image forming apparatus according to first and second embodiments. [Figure 2] FIG. 1 is a schematic perspective view showing a scanning optical device according to a first embodiment of the present invention; [Figure 3] 1 is a schematic cross-sectional view showing an oblique incidence optical system for a rotating polygon mirror of a scanning optical device according to a first embodiment. [Figure 4] 1 is a schematic cross-sectional view showing a scanning optical system of a scanning optical device according to a first embodiment. [Figure 5] Schematic perspective view showing the shape of the laser support of Example 1. [Figure 6] FIG. 1 is a schematic perspective view showing the shape of an optical box around the adhesive portion with the laser support in Example 1. [Figure 7] FIG. 1 is a schematic perspective view showing a semiconductor laser position adjustment tool according to a first embodiment of the present invention; [Figure 8] Schematic cross-sectional view showing a semiconductor laser position adjustment tool according to the first embodiment. [Figure 9] 1A and 1B are a schematic perspective view and a top view showing a state in which a plurality of laser supports are adhesively fixed to an optical box according to the first embodiment; [Figure 10] 1 is a schematic cross-sectional view showing the adhesive portion between a plurality of laser supports and an optical box in Example 1, and a schematic front view showing the plurality of laser supports and a gripping portion of the laser supports. [Figure 11] FIG. 10 is a schematic perspective view showing a scanning optical device according to a second embodiment. [Figure 12] FIG. 10 is a schematic cross-sectional view showing a scanning optical system of a scanning optical device according to a second embodiment. [Figure 13] FIG. 10 is a schematic perspective view showing the shape of the optical box around the adhesive portion with the laser support in Example 2. [Figure 14] FIG. 10 is a schematic perspective view showing a state in which a plurality of laser supports are adhesively fixed to an optical box according to a second embodiment. [Figure 15]10 is a schematic cross-sectional view showing the adhesive portion between the laser supports and the optical box in Example 2, and a schematic front view showing the laser supports and the gripping portion of the laser supports. DETAILED DESCRIPTION OF THE INVENTION [Example]

[0012] A first embodiment of an image forming apparatus 1 according to the present invention will be described with reference to FIGS. (Image forming device overview) 1 is a schematic cross-sectional view of an image forming apparatus 1 of Example 1. The image forming apparatus 1 of Example 1 is a color image forming apparatus that forms a full-color image by superimposing four colors of yellow, cyan, magenta, and black.

[0013] Next, the image forming process will be described. The process cartridges PY, PM, PC, and PK, each corresponding to a different color, are equipped with photosensitive drums 11a, 11b, 11c, and 11d as image carriers. Here, Y, M, C, and K represent the respective colors. The process cartridges PY, PM, PC, and PK may also be collectively referred to as process cartridge P. Furthermore, the letters a, b, c, and d that correspond to the colors in FIG. 1 may be omitted except when describing components of a specific color.

[0014] The process cartridge P also includes a charging roller 12 as a charger and a developing roller 13 as a developing means of a developing device. The photosensitive drum 11, which has been pre-charged by the charging roller 12, is irradiated with laser beams L1, L2, L3, and L4 emitted from the scanning optical device 2 as an exposure device, forming an electrostatic latent image on its surface. The electrostatic latent image is converted into a toner image by the developing roller 13, and then transferred onto the intermediate transfer belt 21 by the primary transfer roller 22 (primary transfer). Meanwhile, a recording sheet S, serving as a recording material, placed in a paper cassette 31 located below the intermediate transfer belt 21 is picked up by a pickup roller 32 in synchronization with the image formation process. The four-color toner image on the intermediate transfer belt 21 is then transferred onto the transported recording sheet S by the secondary transfer roller 33 (secondary transfer). Finally, the recording sheet S passes through a fuser 34 to fuse the toner image, and is then discharged by discharge rollers 35 and 36 to a discharge tray 37 outside the image forming apparatus 1.

[0015] (Scanning optical device overview) Next, a description will be given of the scanning optical device 2 of Example 1. For convenience of explanation, Fig. 2 is a diagram showing the scanning optical device 2 upside down relative to the state in use, and with a cover (not shown) and control boards 125 and 126 removed from the optical box 101. In the coordinate system of Example 1, the direction of the rotation axis of the rotating polygon mirror 103 is defined as the Z direction, the scanning direction of the laser beams L1, L2, L3, and L4 deflected and scanned by the rotating polygon mirror 103 is defined as the Y direction, and the direction perpendicular to the Y and Z directions is defined as the X direction.

[0016] The scanning optical device 2 has a scanner motor 104 having a rotating polygonal mirror 103, and an anamorphic lens 113 which is an imaging member for the laser beams L1, L2, L3, and L4. The scanning optical device 2 also has a first imaging lens 116, second imaging lenses 119a and 119b, a first reflecting mirror 117, a second reflecting mirror 118, and a third reflecting mirror 120 which are reflecting members, and an optical box 101 which mounts or houses these.

[0017] Laser beams L1, L2, L3, and L4 emitted from semiconductor laser 111 are converted into approximately parallel or convergent beams in the X direction and convergent beams in the Z direction by anamorphic lens 113, which is an integrally formed collimator lens and cylindrical lens. Anamorphic lens 113 is mounted as a common lens for laser beams L1, L2 and laser beams L3 and L4. The beam widths of laser beams L1, L2, L3, and L4 are then limited by sub-scanning aperture diaphragms and main-scanning aperture diaphragms (not shown), and the beams are focused onto the deflecting reflecting surface of rotating polygon mirror 103 as linear images having a certain width in the X direction.

[0018] A scanner motor 104 that rotates the rotary polygon mirror 103 around its rotation axis is attached to the optical box 101 with screws (not shown). A laser support 112 that serves as a support member that houses the semiconductor laser 111 is adhesively fixed to the optical box 101 after the position of the semiconductor laser 111, which will be described later, has been adjusted.

[0019] Beam detector (hereinafter referred to as BD) 124 is mounted on a control board 125. In the first embodiment, laser light beam L4 is reflected by the rotating polygon mirror 103, deflected and scanned, and then incident on BD 124. At this time, the writing of images of each color is controlled based on a signal (BD signal) output from BD 124. Note that control boards 125 and 126 are attached to the optical box 101 with screws (not shown), and are each electrically connected to two semiconductor lasers 111 in the Z direction.

[0020] The oblique incidence optical system of Example 1 will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view of the incidence optical system showing the optical paths of laser beams L1 and L2 until they reach the rotating polygon mirror 103. Note that the optical paths of laser beams L3 and L4 have the same configuration as those of laser beams L1 and L2, and therefore description thereof will be omitted. The oblique incidence optical system is an optical system that makes laser beams L1 and L2 obliquely incident on the deflection reflection surface of the rotating polygon mirror 103. That is, two laser supports 112 serving as support members containing semiconductor lasers 111 serving as light sources are arranged in the Z direction and tilted with respect to the Y axis.

[0021] Specifically, a laser support 112a serving as a first support member and containing a semiconductor laser 111a serving as a first light source is disposed on the positive side in the Z direction of the optical box 101. Furthermore, a laser support 112b serving as a second support member and containing a semiconductor laser 111b serving as a second light source is disposed on the negative side in the Z direction of the optical box 101. The number of semiconductor lasers 111 and laser supports 112 is not limited to two, and there may be at least two or more. With this configuration, the laser beams L1 and L2 emitted from the semiconductor laser 111 are incident on the deflection-reflection surface of the rotating polygon mirror 103 at a desired incident angle θ with respect to a plane B that is parallel to the scanning plane and passes through the deflection-reflection point RC of the rotating polygon mirror 103.

[0022] Next, the scanning optical system of the laser beams L1, L2, L3, and L4 after being reflected by the rotating polygon mirror 103 in the first embodiment will be described with reference to Fig. 4. Fig. 4 is a cross-sectional view of the scanning optical system showing the optical paths of the laser beams L1, L2, L3, and L4 deflected and scanned by the rotating polygon mirror 103 until they reach the photosensitive drums 11a, 11b, 11c, and 11d.

[0023] Since the first embodiment is an oblique incidence optical system, the laser beams L1 and L3 are reflected in the negative direction in the Z direction by the rotating polygon mirror 103, and the laser beams L2 and L4 are reflected in the positive direction. The laser beams L1, L2, L3, and L4 then enter the first imaging lens 116. The laser beams L2 and L3 are then reflected by the first reflecting mirror 117. After passing through the second imaging lens 119a, they are reflected again by the second reflecting mirror 118 and reach the photosensitive drums 11b and 11c. The laser beams L1 and L4 also pass through the second imaging lens 119b, then reflected by the third reflecting mirror 120 and reach the photosensitive drums 11a and 11d. Each imaging lens is fixed to the optical box 101 with a UV adhesive, and each reflecting mirror is fixed to the optical box 101 with a biasing member (not shown). A cover 102 for preventing dust particles from entering the scanning optical device 2 is attached to the optical box 101 with screws (not shown).

[0024] Hereinafter, a method for adjusting the position of the semiconductor laser 111 and a method for fixing the laser support 112 to the optical box 101 will be described. Note that the method for adjusting the position of each of the semiconductor lasers 111 that emit laser beams L1, L2, L3, and L4 and the method for fixing the laser support 112 that houses each of the semiconductor lasers 111 are all similar. Therefore, in Example 1, the semiconductor laser 111 that emits laser beam L1 and the laser support 112 that houses it will be described as representatives.

[0025] (Outer shape of laser support) Next, the shape of the laser support 112 of Example 1 will be described. FIGS. 5(a) and 5(b) are perspective projection views of the laser support 112 housing the semiconductor laser 111. The laser support 112 has a gripping portion 140 serving as a holder, a cylindrical portion 130, and a reference surface 145. The gripping portion 140 has two substantially V-shaped portions symmetrically arranged with respect to an axis CZ that passes through the center LC of the semiconductor laser 111 and is parallel to the Z axis. More specifically, in the X direction, the gripping portion 140a serving as a first gripping portion is provided in the positive direction, and the gripping portion 140b serving as a second gripping portion is provided in the negative direction. The cylindrical portion 130 is an adhesive portion for bonding to an optical box (not shown) and is provided at a different position from the gripping portion 140 in the Y direction (direction of the optical axis). The reference surface 145 is one of four surfaces that serve as a reference in the Y direction.

[0026] (Shape of the optical box around the adhesive part that fixes the laser support) Next, the shape of the optical box 101 around the adhesive portion (cylindrical portion 130) with the laser support 112 in Example 1 will be described. FIG. 6 is a projected perspective view of the optical box 101 around the adhesive portion. The optical box 101 extends in the Y direction and has two adhesive portions 150a and 150b in the Z direction, each of which is configured as a pair of protrusions in the X direction. In the Z direction, the adhesive portion 150a as a first adhesive portion is provided in the + direction, and the adhesive portion 150b as a second adhesive portion is provided in the - direction. Furthermore, in the X direction, the adhesive portion 150a has an adhesive portion 150a1 as a third adhesive portion provided in the + direction, and an adhesive portion 150a2 as a fourth adhesive portion provided in the - direction. In addition, in the X direction, the adhesive portion 150b has an adhesive portion 150b1 as a fifth adhesive portion provided in the + direction, and an adhesive portion 150b2 as a sixth adhesive portion provided in the - direction.

[0027] The adhesive portion 150a2 is provided at a position 180 degrees from the adhesive portion 150a1 on the circumference of a first virtual circle centered on the optical axis of the semiconductor laser 111a. In other words, the adhesive portions 150a1 and 150a2 are provided at positions that divide the circumference of the first virtual circle into two equal parts. The adhesive portion 150b2 is provided at a position 180 degrees from the adhesive portion 150b1 on the circumference of a second virtual circle centered on the optical axis of the semiconductor laser 111b. In other words, the adhesive portions 150b1 and 150b2 are provided at positions that divide the circumference of the second virtual circle into two equal parts.

[0028] In the second embodiment, two adhesive portions are provided for one laser support 112, but this is not limiting. Adhesive portions may be provided at least in two or more places for one laser support 112, at positions equally dividing the circumference of an imaginary circle whose center is the optical axis of the semiconductor laser 111. In this case, it is sufficient that the imaginary lines connecting the adhesive portions and the optical axis are arranged in the same direction for the multiple laser supports 112.

[0029] (Method for adjusting the position of the semiconductor laser and fixing the laser support to the optical box) Next, a method for adjusting the position of the semiconductor laser 111 and fixing the laser support 112 to the optical box 101 in Example 1 will be described. Fig. 7 is a projected perspective view of a schematic diagram of a tool for adjusting the position of the semiconductor laser 111, and Fig. 8 is a diagram showing a cross-sectional view of the position adjustment tool. The tool for adjusting the position of the semiconductor laser 111 includes a spot observation system device 160 such as a CCD camera, and a clamping tool 170 as a gripping member. The clamping tool 170 is movable in three directions, X, Y, and Z, by a three-axis stage (not shown).

[0030] (Position adjustment method) 7, the clamping tool 170 clamps the two gripping parts 140 in the X direction and grips the laser support 112 while abutting against the reference surface 145 shown in FIG. 5. With this gripping configuration, the laser support 112 is gripped while being positioned in the X, Y, and Z directions relative to the clamping tool 170. In this state, the clamping tool 170 sets the laser support 112 at a predetermined position using a three-axis stage (not shown), and causes the semiconductor laser 111 to emit light using a semiconductor laser emission circuit (not shown), thereby emitting a laser beam L1.

[0031] Thereafter, as shown in Fig. 8, the laser beam L1 passes through each optical component, including an anamorphic lens, a first imaging lens 116, a second imaging lens 119b, and a third reflecting mirror 120 (not shown), and forms an image on a spot observation system 160 provided at a position corresponding to the photosensitive drum 11a. Note that only necessary reference numerals are used in Fig. 8. While observing the imaging state and imaging position of the spot of the laser beam L1 on the spot observation system 160, the semiconductor laser 111 is moved together with the laser support 112 by a three-axis stage (not shown) to an optimal position in each coordinate system.

[0032] (Fixing method) Once the position adjustment of the semiconductor laser 111 is complete, a photocurable adhesive (not shown) is applied to the cylindrical portion 130 of the laser support 112 and two adhesive portions 150a1 and 150a2 of the optical box 101. Thereafter, an irradiator (not shown) irradiates the adhesive with light for curing the adhesive, hardening it and adhesively fixing the laser support 112 to the optical box 101. Thereafter, the clamping tool 170 is retracted in the X direction (away from the gripping portion 140) by a three-axis stage (not shown), and then retreats in the Y direction (moves in the -Y direction), thereby releasing the gripped state of the laser support 112.

[0033] By using this method, the semiconductor laser 111 can be adjusted to an optimum position in a state in which each optical component, such as an anamorphic lens (not shown), the first imaging lens 116, the second imaging lens 119b, and the third reflecting mirror 120, is assembled in the optical box 101. This makes it possible to adjust the position of the semiconductor laser 111 in a state in which there is a focus error of the spot of the laser light beam L1 on the photosensitive drum 11, which occurs due to manufacturing errors of each optical component and the optical box 101, or assembly errors of each optical component to the optical box 101.

[0034] (Adhesion of two adjacent laser supports to the optical box) Next, a description will be given of the configuration when two adjacent laser supports 112 of Example 1 are adhesively fixed to the optical box 101. Fig. 9(a) is a projected perspective view showing a state in which two adjacent laser supports 112a and 112b are adhesively fixed to the optical box 101, and Fig. 9(b) is a top view.

[0035] As shown in FIG. 9(a), in the first embodiment, two laser supports 112a and 112b are adhesively fixed to the optical box 101 in a state where they are arranged side by side in the Z direction. Of the two laser supports 112a and 112b, the laser support 112a located on the positive side in the Z direction houses the semiconductor laser 111 (111a) that emits the laser beam L1 shown in FIG. 2. The laser support 112b located on the negative side houses the semiconductor laser 111 (111b) that emits the laser beam L2 shown in FIG. 2. This configuration realizes the oblique incidence optical system described above. Each laser support 112 is adhesively fixed to the optical box 101 after the position of the semiconductor laser 111 has been adjusted.

[0036] Also, as shown in FIG. 9(b), the bonding points between the laser support 112 and the optical box 101, specifically the cylindrical portion 130 and the bonding portion 150b, are provided at positions in the Y direction different from the gripping portion 140 gripped by the clamping tool 170 (FIG. 7).

[0037] (The relative position of the adhesive part with respect to the two adjacent laser supports) Next, a description will be given of the relative positional relationship of the adhesive portions 150a and 150b with respect to the laser support 112 in Example 1. Fig. 10(a) is a cross-sectional view showing a state in which two adjacent laser supports 112a and 112b are adhesively fixed to the optical box 101.

[0038] In the first embodiment, a straight line Lc connecting the centers LC of the two semiconductor lasers 111a and 111b intersects with straight lines La and Lb connecting the two adhesive portions 150a and 150b. Here, the straight line Lc can be considered to be the arrangement direction in which the semiconductor lasers 111 and the laser supports 112 are arranged. The arrangement direction in the first embodiment is the Z direction, or in other words, the rotation axis direction of the rotary polygon mirror 103. The straight lines La and Lb are in a direction different from the arrangement direction, and the adhesive portions 150a and 150b can be considered to be arranged in a direction different from the arrangement direction. Furthermore, the straight line La can be considered to be a virtual line (first virtual line) connecting the adhesive portion 150a1 and the adhesive portion 150a2, and the straight line Lb can be considered to be a virtual line (second virtual line) connecting the adhesive portion 150b1 and the adhesive portion 150b2. With this configuration, by arranging the adhesive portions 150a, 150b in a direction other than the arrangement direction (Z direction) of the two laser supports 112, the distance between the laser supports 112 can be narrowed, and the scanning optical device 2 can be made smaller in the height direction (Z direction).

[0039] Furthermore, by narrowing the distance between the laser supports 112, it is possible to reduce the incident angle θ of each of the laser beams L1, L2, L3, and L4 onto the deflection reflection surface of the rotating polygon mirror 103 shown in Fig. 3. By reducing the incident angle θ, it is possible to prevent a decrease in optical performance and improve the quality of the scanning optical device 2. Furthermore, it is possible to reduce the size in the height direction (Z direction) of the anamorphic lens 113, which is installed as a common lens for the laser beams L1 and L2 and the laser beams L3 and L4.

[0040] Furthermore, by narrowing the distance between the laser supports 112, the distance between adjacent semiconductor lasers 111 can also be narrowed, thereby realizing miniaturization in the height direction (Z direction) of the control boards 125, 126 to which the two semiconductor lasers 111 are electrically connected in the Z direction.

[0041] (Relative positional relationship of the gripping part to the two adjacent laser supports) Next, a description will be given of the relative positional relationship of the gripping portion 140 with respect to the laser support 112 in Example 1. Fig. 10(b) is a front view showing a state in which two adjacent laser supports 112a and 112b are adhesively fixed to the optical box 101.

[0042] In the first embodiment, a straight line Lc connecting the centers LC of the two semiconductor lasers 111a and 111b intersects with straight lines Ld and Le connecting the centers IC of the inscribed circles Ci inscribed in the substantially V-shape of the gripping unit 140. The adhesive portions 150a and 150b and the gripping unit 140 are arranged in substantially the same direction with respect to the optical axis of the semiconductor laser 111. This configuration can prevent the clamping tool 170 shown in FIG. 7 from colliding with the adjacent laser supports 112 when it retreats in the X direction. In other words, by providing a retreat space for the clamping tool 170 shown in FIG. 7 in a direction different from the arrangement direction (Z direction) of the laser supports 112, the distance between the laser supports 112 can be narrowed, and the scanning optical device 2 can be made smaller in the height direction (Z direction).

[0043] In the above description, the adhesive portions 150a and 150b are configured such that the straight line Lc connecting the centers LC of the two semiconductor lasers 111 intersects with the straight lines La and Lb connecting the two adhesive portions 150a and 150b. However, if the straight line Lc connecting the centers LC of the two semiconductor lasers 111 intersects with the straight lines La and Lb connecting the two adhesive portions 150a and 150b at right angles (in the X direction), the distance between the laser supports 112 can be made narrower.

[0044] Furthermore, with regard to the gripping unit 140, a configuration has been described in which the straight line Lc connecting the centers LC of the two semiconductor lasers 111 intersects with the straight lines Ld and Le connecting the centers IC of the inscribed circles Ci inscribed in the approximate V-shape of the gripping unit 140. However, a configuration may also be adopted in which the straight line Lc connecting the centers LC of the two semiconductor lasers 111 intersects with the straight lines Ld and Le connecting the centers IC of the inscribed circles Ci inscribed in the approximate V-shape of the gripping unit 140 at right angles (in the X direction). This makes it possible to ensure more space when the clamping tool 170 retreats from the gripping unit 140.

[0045] With this configuration, the adhesive portion between the laser support and the optical box can be located at a position other than between two adjacent laser supports, thereby narrowing the gap between the laser supports, thereby realizing a compact scanning optical device that has a configuration in which multiple laser supports are adhesively fixed after their positions are adjusted.

[0046] As described above, according to the first embodiment, even in the configuration in which a plurality of laser supports are adhesively fixed to the optical box after their positions are adjusted, it is possible to achieve a reduction in the size of the scanning optical device. [Example]

[0047] Next, a second embodiment of the image forming apparatus according to the present invention will be described in detail with reference to Figures 11 to 15. The configuration of the laser support 112 is the same as that of the first embodiment, and the same functions and shapes as those of the first embodiment are denoted by the same reference numerals and will not be described.

[0048] (scanning optical device) Next, a scanning optical device 200 according to a second embodiment will be described. Fig. 11 is a diagram illustrating the scanning optical device 200 with a cover (not shown) removed for ease of explanation. In the coordinate system of the second embodiment, the direction of the rotation axis SC of the rotating polygon mirror 103 is defined as the Z direction, the scanning direction of the laser beams L1, L2, L3, and L4 deflected and scanned by the rotating polygon mirror 103 is defined as the Y direction, and the direction perpendicular to the Y and Z directions is defined as the X direction.

[0049] The scanning optical device 200 includes an anamorphic lens 203, which is an imaging member for the laser beams L1, L2, L3, and L4, a first imaging lens 208, a second imaging lens 209, a reflecting mirror 210, which is a reflecting member, and a BD lens 211, and an optical box 201 to which these are attached. The laser beams L1, L2, L3, and L4 emitted from the semiconductor laser 111 are converted into approximately parallel or convergent light in the X direction and convergent light in the Z direction by the anamorphic lens 203, which is an integrally molded collimator lens and cylindrical lens. The anamorphic lens 203 is mounted as a common lens for the laser beams L1 and L2, and for the laser beams L3 and L4. Thereafter, the widths of the laser beams L1, L2, L3, and L4 are limited by the sub-scanning aperture stop and the main-scanning aperture stop (not shown), and the beams are imaged linearly with a certain width in the X direction on the deflection reflection surface of the rotating polygon mirror 103.

[0050] Furthermore, laser supports 112 containing semiconductor lasers 111 are arranged in parallel in the X direction and tilted with respect to the Y axis. With this configuration, laser beams L1, L2, L3, and L4 emitted from semiconductor lasers 111 are incident on the deflecting reflecting surfaces of rotating polygon mirrors 103 at a desired incident angle θ2 with respect to plane C that is perpendicular to the scanning plane and parallel to the Y axis and passes through rotation axes SC of each rotating polygon mirror 103.

[0051] Two scanner motors 104 are mounted to rotate the rotating polygon mirror 103 around the rotation axis SC, for deflection scanning the laser beams L1 and L2, and the laser beams L3 and L4. Each of these is attached to the optical box 201 with screws (not shown). The BD 212 is mounted on a control board 213. In the second embodiment, the laser beams L1 and L3 reflected by the rotating polygon mirror 103 and deflection-scanned pass through the BD lens 211 and are incident on the BD 212 in an image-formed state. At this time, the writing of images for each color is controlled based on a signal (BD signal) output from the BD 212. The control board 213 is attached to the optical box 201 with screws (not shown), and is electrically connected to the two semiconductor lasers 111 in the X direction.

[0052] Next, the scanning optical system of the laser beams L1, L2, L3, and L4 after reflection by the rotary polygon mirror 103 in the second embodiment will be described with reference to Fig. 12. Fig. 12 is a cross-sectional view in the sub-scanning direction of the scanning optical system, showing the optical paths of the laser beams L1, L2, L3, and L4 deflected and scanned by the rotary polygon mirror 103 until they reach the photosensitive drums 11a, 11b, 11c, and 11d. Note that the optical paths of the laser beams L1, L2, L3, and L4 after reflection by the rotary polygon mirror 103 all have the same configuration, so in the second embodiment, the optical path of the laser beam L1 will be described as a representative.

[0053] The laser beam L1 reflected by the rotating polygon mirror 103 is incident on a first imaging lens 208. Thereafter, the laser beam L1 is reflected by a reflecting mirror 210, passes through a second imaging lens 209, and then reaches the photosensitive drum 11a. Each imaging lens is fixed to the optical box 201 with a UV adhesive, and each reflecting mirror is fixed to the optical box 201 with a biasing member (not shown). A lid 202 for preventing dust particles from entering the scanning optical device 200 is attached to the optical box 201 with screws (not shown).

[0054] The scanning optical device 200 of the second embodiment is costly because it includes two scanner motors 104 and four first imaging lenses 208. However, by using only one reflecting mirror 210 for each of the laser beams L1, L2, L3, and L4, the scanning optical device 200 can be made thinner, which in turn contributes to the miniaturization and cost reduction of the entire image forming apparatus.

[0055] (Shape of the optical box around the adhesive part that fixes the laser support) Next, the shape of the optical box 201 around the adhesive portion that adhesively fixes the laser support 112 of the second embodiment will be described. FIG. 13 is a projected perspective view of the optical box 201 around the adhesive portion. The optical box 201 has two adhesive portions 250a and 250b in the X direction, each of which extends in the Y direction and has a pair of protrusion shapes in the Z direction. In the X direction, the adhesive portion 250a as the first adhesive portion is provided in the + direction, and the adhesive portion 250b as the second adhesive portion is provided in the - direction. Furthermore, in the Z direction, the adhesive portion 250a has an adhesive portion 250a1 as the third adhesive portion provided in the + direction, and an adhesive portion 250a2 as the fourth adhesive portion provided in the - direction. In addition, in the Z direction, the adhesive portion 250b has an adhesive portion 250b1 as the fifth adhesive portion provided in the + direction, and an adhesive portion 250b2 as the sixth adhesive portion provided in the - direction. The adhesive portion 250a2 is provided at a position 180 degrees from the adhesive portion 250a1 on the circumference of a first virtual circle centered on the optical axis of the semiconductor laser 111a. In other words, the adhesive portions 250a1 and 250a2 are provided at positions that divide the circumference of the first virtual circle into two equal parts. The adhesive portion 250b2 is provided at a position 180 degrees from the adhesive portion 250b1 on the circumference of a second virtual circle centered on the optical axis of the semiconductor laser 111b. In other words, the adhesive portions 250b1 and 250b2 are provided at positions that divide the circumference of the second virtual circle into two equal parts.

[0056] In the second embodiment, two adhesive portions are provided for one laser support 112, but the present invention is not limited to this. Adhesive portions may be provided at least in two or more places for one laser support 112, at positions equally dividing the circumference of an imaginary circle whose center is the optical axis of the semiconductor laser 111. In this case, it is sufficient that the imaginary lines connecting the adhesive portions and the optical axis are arranged in the same direction for the multiple laser supports 112.

[0057] (Adhesion of two adjacent laser supports to the optical box) Next, a description will be given of the configuration when two adjacent laser supports 112 of Example 2 are adhesively fixed to the optical box 201. Fig. 14(a) is a projected perspective view showing the state in which two adjacent laser supports 112 are adhesively fixed to the optical box 201, and Fig. 14(b) is a top view. Each laser support 112 is adhesively fixed to the optical box 201 in the same manner as described in Example 1.

[0058] 14(a), in Example 2, two laser supports 112 are arranged side by side in the X direction and adhesively fixed to the optical box 201. Of the two laser supports 112a and 112b, the laser support 112a located on the + side in the X direction houses the semiconductor laser 111 (111a) that emits the laser beam L1 shown in FIG. 11. On the other hand, the laser support 112b located on the - side houses the semiconductor laser 111 (111b) that emits the laser beam L2 shown in FIG.

[0059] 14(b), the cylindrical portion 130 of the laser support 112 and the adhesive portions 250a and 250b of the optical box 201 are adhesively fixed with a photocurable adhesive (not shown). The adhesive fixation is performed at a position different from the gripping portion 140 gripped by the clamping tool 170 shown in FIG. 7 when adjusting the position of the semiconductor laser 111 in the Y direction.

[0060] (The relative position of the adhesive part with respect to the two adjacent laser supports) Next, a description will be given of the relative positional relationship between the adhesive portions 250a and 250b and the laser support 112 in Example 2. Fig. 15(a) is a cross-sectional view showing a state in which two adjacent laser supports 112 are adhesively fixed to the optical box 201.

[0061] In the second embodiment, a straight line Lc connecting the centers LC of the two semiconductor lasers 111a and 111b intersects with straight lines Lf and Lg connecting the two adhesive portions 250a and 250b. Here, the straight line Lc can be considered to be the arrangement direction in which the semiconductor lasers 111 and the laser supports 112 are arranged. The arrangement direction in the second embodiment is the X direction, or in other words, a direction perpendicular to the rotation axis direction of the rotary polygon mirror 103. The straight lines Lf and Lg are in a direction different from the arrangement direction, and the adhesive portions 250a and 250b can be considered to be arranged in a direction different from the arrangement direction. The straight line Lg can be considered to be a virtual line (first virtual line) connecting the adhesive portion 250a1 and the adhesive portion 250a2, and the straight line Lf can be considered to be a virtual line (second virtual line) connecting the adhesive portion 250b1 and the adhesive portion 250b2. With this configuration, by arranging the adhesive portions 250a, 250b in a direction other than the arrangement direction (X direction) of the two laser supports 112, the distance between the laser supports 112 can be narrowed, and the scanning optical device 2 can be made smaller in the width direction (X direction).

[0062] Furthermore, by narrowing the gap between the laser supports 112, it is possible to reduce the incident angle θ2 of each of the laser beams L1, L2, L3, and L4 onto the deflection reflection surface of the rotating polygon mirror 103 shown in Fig. 11. By reducing the incident angle θ2, it is possible to reduce the size in the width direction (X direction) of the anamorphic lens 113 mounted as a common lens for the laser beams L1 and L2 and the laser beams L3 and L4.

[0063] Furthermore, since the arrangement space for the BD lens 211 shown in Fig. 11 can be secured, the degree of freedom in designing the BD optical system is improved. Furthermore, the control board 213 shown in Fig. 11 monitors and automatically adjusts the light emission amount of the semiconductor laser 111 so that the semiconductor laser 111 always emits laser beams L1, L2, L3, and L4 at the desired brightness (hereinafter referred to as APC (Auto Power Control)). To avoid affecting the actual printed image, APC must be performed within the time from when the laser beams L1, L2, L3, and L4 reflected by the rotating polygon mirror 103 directly face the respective semiconductor lasers 111 to when the image writing for each color begins. In other words, by reducing the incident angle θ2, this time interval can be widened, thereby improving the degree of freedom in designing the timing at which APC is performed.

[0064] Furthermore, by narrowing the distance between the laser supports 112, the distance between adjacent semiconductor lasers 111 can also be narrowed, thereby realizing a reduction in the width direction (X direction) of the control board 213 to which the two semiconductor lasers 111 are electrically connected in the X direction.

[0065] (The relative position of the adhesive part with respect to the two adjacent laser supports) Next, a description will be given of the relative positional relationship of the gripping portion 140 with respect to the laser supports 112 in Example 2. Fig. 15(b) is a front view showing a state in which two adjacent laser supports 112 are adhesively fixed to the optical box 201.

[0066] In the second embodiment, a straight line Lc connecting the centers LC of the two semiconductor lasers 111 intersects with straight lines Lh and Li connecting the centers IC of the inscribed circles Ci inscribed in the approximately V-shape of the gripping unit 140. Furthermore, the adhesive portions 250a and 250b and the gripping unit 140 are arranged in approximately the same direction with respect to the optical axis of the semiconductor lasers 111. This configuration can prevent the clamping tool 170 shown in FIG. 7 from colliding with the adjacent laser supports 112 when it retreats in the Z direction. In other words, by providing a retreat space for the clamping tool 170 shown in FIG. 7 in a direction different from the arrangement direction (X direction) of the laser supports 112, the distance between the laser supports 112 can be narrowed, and the scanning optical device 2 can be made smaller in the width direction (X direction).

[0067] By using this configuration, the adhesive portion can be provided at a position other than between the two laser supports, thereby narrowing the distance between the laser supports, thereby realizing the miniaturization of a scanning optical device that has a configuration in which multiple laser supports are adhesively fixed after their positions are adjusted.

[0068] As described above, according to the second embodiment, even in the configuration in which a plurality of laser supports are adhesively fixed to the optical box after their positions are adjusted, it is possible to achieve a reduction in the size of the scanning optical device.

[0069] The disclosure of this embodiment includes the following configuration. (Configuration 1) Multiple light sources; a plurality of support members each containing a plurality of the light sources; a rotating polygon mirror that deflects and scans the light beam emitted from the light source; an optical box that houses a plurality of the support members and the rotary polygon mirror; a scanning optical device in which a plurality of the support members whose positions are adjusted are adhesively fixed to the optical box, At least two of the support members are arranged adjacent to each other in the arrangement direction, the optical box has an adhesive portion that is adhered to the support member, 10. A scanning optical device according to claim 9, wherein the adhesive portions are arranged in a direction different from the arrangement direction. (Configuration 2) The scanning optical device described in configuration 1 is characterized in that the adhesive portions are provided in at least two locations on one support member, at positions equally dividing the circumference of an imaginary circle centered on the optical axis of the light source, and the imaginary lines connecting the adhesive portions and the optical axis are arranged in the same direction for multiple support members. (Configuration 3) the support member has a holding portion that is gripped when the position is adjusted, 3. The scanning optical device according to configuration 1 or 2, wherein the holding portion and the adhesive portion are arranged in substantially the same direction with respect to the optical axis of the light source. (Configuration 4) 4. The scanning optical device according to configuration 3, wherein the holding portion is provided at a position different from the adhesive portion in the direction of the optical axis. (Configuration 5) A first light source; A second light source; a first support member that contains the first light source; a second support member that contains the second light source; a rotating polygon mirror that deflects and scans the light beams emitted from the first light source and the second light source; an optical box that houses the first support member, the second support member, and the rotary polygon mirror; and wherein the first support member and the second support member, whose positions have been adjusted, are adhesively fixed to the optical box, the first support member and the second support member are arranged adjacent to each other in an arrangement direction, the optical box has a first adhesive portion that is adhered to the first support member and a second adhesive portion that is adhered to the second support member, 10. A scanning optical device, wherein the first adhesive portion and the second adhesive portion are arranged in a direction different from the arrangement direction. (Configuration 6) the first adhesive portion has a third adhesive portion and a fourth adhesive portion provided at a position 180 degrees apart from the third adhesive portion on the circumference of a first virtual circle centered on the optical axis of the first light source, the second adhesive portion includes a fifth adhesive portion and a sixth adhesive portion provided at a position 180 degrees apart from the fifth adhesive portion on the circumference of a second virtual circle centered on the optical axis of the second light source, When a virtual line connecting the third adhesive portion and the fourth adhesive portion is defined as a first virtual line, and a virtual line connecting the fifth adhesive portion and the sixth adhesive portion is defined as a second virtual line, 6. The scanning optical device according to configuration 5, wherein the first virtual line and the second virtual line are arranged to be in the same direction. (Configuration 7) the first support member has a first gripping portion that is gripped by a gripping member when the position is adjusted; the second support member has a second gripping portion that is gripped by the gripping member when the position is adjusted, The first gripping portion is provided in the same direction as the first virtual line, 7. The scanning optical device according to claim 5, wherein the second gripping portion is provided in the same direction as the second virtual line. (Configuration 8) the first gripping portion is provided at a position different from the first adhesive portion in a direction of the optical axis of the first light source, 8. The scanning optical device according to configuration 7, wherein the second gripping portion is provided at a position different from the second adhesive portion in the direction of the optical axis of the second light source. (Configuration 9) 9. The scanning optical device according to any one of configurations 1 to 8, wherein the arrangement direction is a direction of a rotation axis of the rotary polygon mirror. (Configuration 10) 9. The scanning optical device according to any one of configurations 1 to 8, wherein the arrangement direction is a direction perpendicular to the rotation axis direction of the rotating polygon mirror. (Configuration 11) a scanning optical device according to any one of configurations 1 to 10; and a plurality of image carriers scanned with the light beam by the scanning optical device; a developing unit for developing the electrostatic latent images formed on the plurality of image carriers; An image forming apparatus comprising: [Explanation of symbols]

[0070] 2. Scanning optical device 101 Optical box 111 Semiconductor laser 112 Laser support 150 Adhesive part

Claims

1. Multiple light sources; a plurality of support members each containing a plurality of the light sources; a rotating polygon mirror that deflects and scans the light beam emitted from the light source; an optical box that houses a plurality of the support members and the rotary polygon mirror; a scanning optical device in which a plurality of the support members whose positions are adjusted are adhesively fixed to the optical box, At least two of the support members are arranged adjacent to each other in the arrangement direction, the optical box has an adhesive portion that is adhered to the support member, 10. A scanning optical device according to claim 9, wherein the adhesive portions are arranged in a direction different from the arrangement direction.

2. The scanning optical device described in claim 1, characterized in that the adhesive portions are provided in at least two locations on one support member, and at positions that equally divide the circumference of an imaginary circle centered on the optical axis of the light source, and the imaginary lines connecting the adhesive portions and the optical axis are arranged in the same direction for multiple support members.

3. the support member has a holding portion that is gripped when the position is adjusted, 2. The scanning optical device according to claim 1, wherein the holding portion and the adhesive portion are arranged in substantially the same direction with respect to the optical axis of the light source.

4. 4. The scanning optical device according to claim 3, wherein the holding portion is provided at a position different from the adhesive portion in the direction of the optical axis.

5. A first light source; A second light source; a first support member that contains the first light source; a second support member that contains the second light source; a rotating polygon mirror that deflects and scans the light beams emitted from the first light source and the second light source; an optical box that houses the first support member, the second support member, and the rotary polygon mirror; a scanning optical device including: the first support member and the second support member, the positions of which are adjusted, and adhesively fixed to the optical box; the first support member and the second support member are arranged adjacent to each other in an arrangement direction, the optical box has a first adhesive portion that is adhered to the first support member and a second adhesive portion that is adhered to the second support member, The scanning optical device, wherein the first adhesive portion and the second adhesive portion are arranged in a direction different from the arrangement direction.

6. the first adhesive portion includes a third adhesive portion and a fourth adhesive portion provided at a position 180 degrees apart from the third adhesive portion on the circumference of a first virtual circle centered on the optical axis of the first light source, the second adhesive portion includes a fifth adhesive portion and a sixth adhesive portion provided at a position 180 degrees apart from the fifth adhesive portion on the circumference of a second virtual circle centered on the optical axis of the second light source, When a virtual line connecting the third adhesive portion and the fourth adhesive portion is defined as a first virtual line, and a virtual line connecting the fifth adhesive portion and the sixth adhesive portion is defined as a second virtual line, 6. The scanning optical device according to claim 5, wherein the first virtual line and the second virtual line are arranged to be in the same direction.

7. the first support member has a first gripping portion that is gripped by a gripping member when the position is adjusted; the second support member has a second gripping portion that is gripped by the gripping member when the position is adjusted, The first gripping portion is provided in the same direction as the first virtual line, 6. The scanning optical device according to claim 5, wherein the second gripping portion is provided in the same direction as the second virtual line.

8. the first gripping portion is provided at a position different from the first adhesive portion in a direction of the optical axis of the first light source, 8. The scanning optical device according to claim 7, wherein the second gripping portion is provided at a position different from the second adhesive portion in the direction of the optical axis of the second light source.

9. 6. The scanning optical device according to claim 1, wherein the arrangement direction is a direction of a rotation axis of the rotary polygon mirror.

10. 6. The scanning optical device according to claim 1, wherein the arrangement direction is a direction perpendicular to the rotation axis direction of the rotary polygon mirror.

11. a scanning optical device according to any one of claims 1 to 8; a plurality of image carriers scanned with the light beam by the scanning optical device; a developing unit for developing the electrostatic latent images formed on the plurality of image carriers; An image forming apparatus comprising:

Images