Optical scanner and image forming apparatus

Abstract

To provide an optical scanner that can reduce the number of components.SOLUTION: An optical scanner of the present disclosure comprises: a light source; a lens that transmits light emitted from the light source; and a housing that is formed with a recess into which the lens is inserted along the optical axis of the lens, and an aperture provided on the optical axis of the lens.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present disclosure relates to an optical scanning device and an image forming apparatus.

Background Art

[0002] In recent years, development of an optical scanning device as described in Patent Document 1 below has been carried out. In this optical scanning device, first, a collimator lens is attached to a lens barrel as a lens holder. Then, an assembly in which the collimator lens and the lens barrel are integrated is fitted into a through hole of a housing to which a light source is attached.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the optical scanning device disclosed in Patent Document 1 above, in order to attach the collimator lens to the housing, a lens barrel is required, so that the number of parts of the optical scanning device increases by the number of lens barrels.

[0005] The present disclosure has been made in view of the above problems. An object of the present disclosure is to provide an optical scanning device and an image forming apparatus with a reduced number of parts.

Means for Solving the Problems

[0006] The optical scanning device of the present disclosure includes a light source, a lens through which light emitted from the light source passes, a first recess into which the lens is inserted along the optical axis of the lens, and a housing in which an aperture (a through opening) is formed on the optical axis of the lens. The image forming apparatus of the present disclosure includes the above-described optical scanning device.

Brief Description of the Drawings

[0007]

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Embodiments for Carrying Out the Invention

[0008] Hereinafter, the optical scanning device according to the embodiment of the present disclosure will be described with reference to the drawings. For the drawings, the same or equivalent elements are denoted by the same reference numerals, and duplicate explanations will not be repeated.

[0009] FIG. 1 is a schematic side view of the image forming apparatus 100 according to the embodiment.

[0010] As shown in FIG. 1, the image forming apparatus 100 is a multifunction device having a scanner function, a copier function, a printer function, a facsimile function, and the like. Therefore, the image forming apparatus 100 can transmit an image of a document read by an image reading device to the outside (corresponding to the scanner function). Further, the image forming apparatus 100 can print an image of a read document or an image received from the outside in color or monochrome on paper (corresponding to the copier function, the printer function, and the facsimile function).

[0011] The optical scanning device 1 according to the present embodiment is used in a printing device such as a multifunction device. However, the optical scanning device 1 may be used in any device as long as it is a device that scans light emitted from a light source. The optical scanning device 1 includes a housing 110 including a bottom surface portion 111 and a side surface portion 112. The detailed structure of the optical scanning device 1 will be described later.

[0012] The image forming apparatus 100 includes an image reading unit 41 at the upper part. Above the image reading unit 41, a document conveying device 50 (ADF) that is supported so as to be openable and closable with respect to the image reading unit 41 is provided. When the document conveying device 50 is opened, the document placement table 44 above the image reading unit 41 is opened. Thereby, a document can be manually placed on the document placement table 44. Further, the document conveying device 50 automatically conveys the document placed on the document placement table 44 onto the image reading unit 41. The image reading unit 41 reads the document placed on the document placement table 44 or the document conveyed from the document conveying device 50 and generates image data.

[0013] The image forming apparatus 100 includes, below the image reading unit 41, an optical scanning device 1, a developing device 2, a photosensitive drum 3, a drum cleaning device 4, a charger 5, an intermediate transfer belt 7, a fixing unit 12, a paper conveyance path Sm, a paper feed cassette 10, a stacking tray 15, etc.

[0014] According to the image forming apparatus 100, a color image using each color of black (K), cyan (C), magenta (M), and yellow (Y) is generated. Further, according to the image forming apparatus 100, image data corresponding to a monochrome image using a single color (for example, black) is also generated.

[0015] The image forming apparatus 100 is provided with four sets of developing devices 2, photosensitive drums 3, drum cleaning devices 4, and chargers 5. Each of the aforementioned four sets forms four types of toner images. Each set of the four sets of developing devices 2, photosensitive drums 3, drum cleaning devices 4, and chargers 5 generates an image of any one color of black, cyan, magenta, and yellow. These four sets constitute four image stations Pa, Pb, Pc, and Pd.

[0016] The drum cleaning device 4 removes and collects the residual toner on the surface of the photosensitive drum 3. The charger 5 uniformly charges the surface of the photosensitive drum 3 to a predetermined potential. The optical scanning device 1 exposes the surface of the photosensitive drum 3 to form an electrostatic latent image. The developing device 2 develops the electrostatic latent image on the surface of the photosensitive drum 3. Thereby, a toner image is formed on the surface of the photosensitive drum 3. By the above-described series of operations, toner images of each color are formed on the surface of each photosensitive drum 3. The detailed structure of the optical scanning device 1 will be described later.

[0017] Above the four photosensitive drums 3, a transfer belt device 8 is provided. Four intermediate transfer rollers 6 are arranged with respect to the four photosensitive drums 3 via an intermediate transfer belt 7. The intermediate transfer belt 7 is stretched between a transfer driving roller 21 and a transfer driven roller 22. The intermediate transfer belt 7 circulates and moves in the direction of arrow C. Residual toner is removed and collected by the belt cleaning device 9. Toner images of each color are sequentially transferred from the surface of each photosensitive drum 3 to the surface of the intermediate belt 7. Thereby, toner images of a plurality of colors are superimposed. As a result, a color toner image is formed on the surface of the intermediate transfer belt 7.

[0018] A nip area is formed between the transfer roller 11a of the secondary transfer unit 11 and the intermediate transfer belt 7. The paper conveyed through the paper conveyance path Sm is conveyed in a state of being sandwiched in the nip area. When the paper passes through the nip area, the toner image on the surface of the intermediate transfer belt 7 is transferred to the paper. Thereafter, the paper is conveyed to the fixing unit 12.

[0019] The fixing unit 12 includes a fixing roller 31 and a pressure roller 32 that rotate with the paper sandwiched therebetween. The fixing unit 12 sandwiches the paper with the toner image transferred therebetween, heats and presses it, and fixes the toner image to the paper.

[0020] The paper feed cassette 10 is a cassette for storing the paper used for image formation, and is provided below the optical scanning device 1. The paper is drawn out from the paper feed cassette 10 by the paper pickup roller 16. Thereafter, the paper is conveyed via the paper conveyance path Sm. Further, the paper is carried out to the stacking tray 15 via the secondary transfer unit 11, the fixing unit 12, and the paper discharge roller 17.

[0021] In the paper conveyance path Sm, the paper is temporarily stopped. Thereby, the leading edges of the paper are aligned. Thereafter, the paper registration roller 14 starts conveying the paper in accordance with the transfer timing of the color toner image in the nip area between the intermediate transfer belt 7 and the transfer roller 11a. When the paper is being conveyed, the conveyance roller 13 and the paper discharge roller 17 facilitate the conveyance of the paper.

[0022] Also, when forming an image not only on the front surface of the paper but also on the back surface, the paper is conveyed in the reverse direction from the paper discharge roller 17 to the paper reversal path Sr. In the paper reversal path Sr, the front and back surfaces of the paper are reversed through the reversal roller 18. Thereby, the paper is led to the paper registration roller 14 again. Thereafter, image formation is performed on the back surface in the same manner as on the front surface. Thereafter, the paper is carried out to the stacking tray 15.

[0023] FIG. 2 is a perspective view of the optical scanning device 1 of the embodiment. FIG. 3 is a perspective view showing a state in which the light source cover 101 and the upper lid 102 are removed from the optical scanning device 1 of the embodiment.

[0024] As shown in FIGS. 2 and 3, the housing 110 includes a bottom surface portion 111 and side surface portions 112 rising from the bottom surface portion 111. The side surface portions are formed along the four sides of the bottom surface portion 111. As shown in FIG. 3, in a state where the light source cover 101 and the upper lid 102 are removed from the optical scanning device 1 shown in FIG. 2, the main part of the optical scanning device 1 is exposed. Inside the housing 110, the optical components constituting the optical scanning device 1 described below are arranged.

[0025] FIG. 4 and FIG. 5 are a schematic perspective view and a schematic plan view respectively showing the positional relationship of the optical components of the optical scanning device 1 of the embodiment. In FIGS. 4 and 5, for ease of viewing the drawings, a part of the optical components in the optical scanning device 1 is extracted and shown.

[0026] As shown in FIGS. 4 and 5, the housing 110 of the optical scanning device 1 incorporates optical components. The optical components include a plurality of laser diodes 81 (81a, 81b, 81c, 81d) and a plurality of collimator lenses 82 (82a, 82b, 82c, 82d). The optical components also include an integrated lens 83 (83a, 83b), a reflection mirror 84, a second expander lens 85, a polygon mirror 86, and an fθ lens 87.

[0027] In FIG. 4, a part of the beam LB emitted from the laser diode 81, specifically the laser diode 81a, is indicated by a dashed line. Although omitted in FIG. 4, the beam LB is similarly emitted from the laser diodes 81b, 81c, 81d other than the laser diode 81a. The plurality of collimator lenses 82 are each provided corresponding to the plurality of laser diodes 81. Each of the plurality of collimator lenses 82 is disposed on the optical path of the beam LB emitted from the laser diode 81.

[0028] The main scanning direction S and the sub-scanning direction H attached to the beam LB are the directions in which the beam LB is scanned and correspond to the direction in which the beam LB spreads. Among the optical paths of the beam LB, between each of the plurality of laser diodes 81 and the reflection mirror 84, the main scanning direction S is parallel to the width direction X. Also, among the optical paths of the beam LB, between each of the plurality of laser diodes 81 and the reflection mirror 84, the sub-scanning direction H is parallel to the height direction Z.

[0029] The integrated lens 83 is disposed on the optical path of the beam LB emitted from the collimator lens 82. In the present embodiment, one integrated lens 83 is provided corresponding to a plurality of laser diodes 81. Specifically, the integrated lens 83 is a vertically long lens that is long in the height direction Z in accordance with a plurality of laser diodes 81 arranged side by side in the height direction Z (sub-scanning direction H). The beams LB emitted from each of the plurality of laser diodes 81 all enter the integrated lens 83.

[0030] In the present embodiment, the integrated lens 83 is a lens having curvatures in different directions for the incident surface and the exit surface. In this way, by integrating two lenses (the cylindrical lens 83a and the first expander lens 83b), the size of the optical scanning device 1 can be reduced.

[0031] Specifically, the incident surface of the integrated lens 83 is the cylindrical lens 83a. The incident surface of the integrated lens 83 acts to narrow the incident beam LB in the sub-scanning direction H. Further, the cylindrical lens 83a adjusts the direction (irradiation angle) of the beam LB passing therethrough in the sub-scanning direction H for emission. The plurality of beams LB that have passed through the cylindrical lens 83a change their emission directions so as to converge with each other in the sub-scanning direction H. When the plurality of beams LB reach the polygon mirror 86, they are most convergent in the sub-scanning direction H. Further, the plurality of beams LB are diffused in the sub-scanning direction H after being reflected by the polygon mirror 86.

[0032] Also, the exit surface of the integrated lens 83 is the first expander lens 83b, and acts to widen the irradiation range of the incident beam LB in the main scanning direction S (width direction X).

[0033] The reflection mirror 84 is disposed on the optical path of the beam LB emitted from the integrated lens 83. The beam LB reflected by the reflection mirror 84 is guided to enter the polygon mirror 86 through the second expander lens 85 which is a curved surface lens.

[0034] The second expander lens 85 is disposed on the optical path between the reflection mirror 84 and the polygon mirror 86. The second expander lens 85 acts to narrow the irradiation range of the incident beam LB in the main scanning direction S. The second expander lens 85 has a curvature corresponding to that of the first expander lens 83b. Thereby, the second expander lens 85 makes the incident beam LB parallel. That is, the beam LB passing through the second expander lens 85 has an unchanged irradiation range in the main scanning direction S.

[0035] The polygon mirror 86 is, for example, a polygon mirror having a plurality of faces and has a rotation axis that rotates by a driving unit such as a motor. The polygon mirror 86 reflects the incident beam LB while rotating. Thereby, the beam LB scans the surface of the photoreceptor drum 3.

[0036] The fθ lens 87 is provided at a position facing the polygon mirror 86. The beam LB emitted from the polygon mirror 86 enters the fθ lens 87. Although not shown, optical components such as lenses and mirrors may be provided in the optical path beyond the fθ lens 87. The beam LB passing through these optical components may scan the surface of the photoreceptor drum 3.

[0037] FIG. 6, FIG. 7, FIG. 8, FIG. 9, and FIG. 10 are, respectively, a perspective view, a plan view, a longitudinal sectional view, a side view, and a cross-sectional view of the main part of the optical scanning device 1 of the embodiment. FIG. 11 is an exploded perspective view showing a state in which a laser diode 81 as an example of a light source, a light source holder 120, and a collimator lens 82 as an example of a lens are removed from the main part of the optical scanning device 1 of the embodiment. FIG. 12, FIG. 13, FIG. 14, and FIG. 15 are, respectively, an external perspective view, a longitudinal sectional view (sectional view taken along line XIV-XIV in FIG. 13), and a longitudinal sectional view (sectional view taken along line XV-XV in FIG. 13) of the main part of the housing 110 of the optical scanning device 1 of the embodiment. FIG. 16 and FIG. 17 are, respectively, a side view, an internal perspective view, and an internal side view (sectional view taken along line XV-XV in FIG. 7) of the main part of the housing 110 of the optical scanning device 1 of the embodiment.

[0038] As shown in FIGS. 6 to 17, the optical scanning device 1 includes a housing 110, a plurality of collimator lenses 82, laser diodes 81, and a plurality of light source holders 120. Each of the plurality of collimator lenses 82 is an example of the lens of the present disclosure. Each of the plurality of laser diodes 81 is an example of the plurality of light sources of the present disclosure. The plurality of light source holders 120 are composed of light source holders 120a, 120b, 120c, and 120d.

[0039] As described above, the housing 110 includes a bottom surface portion 111 and four side surface portions 112 that rise from the four sides of the bottom surface portion 111, respectively. The housing 110 is provided with a plurality of apertures (penetrated openings) 113 and a plurality of recesses 114. In particular, a plurality of apertures (penetrated openings) 113 and a plurality of recesses 114 are provided on one of the four side surface portions. The housing 110 is an integrally formed single member. Therefore, the manufacturing process of the optical scanning device 1 can be facilitated.

[0040] As described above, the plurality of apertures 113 are respectively arranged so as to correspond to the plurality of laser diodes 81 and the plurality of collimator lenses 82. That is, each of the plurality of apertures 113 is arranged so as to correspond to one of the plurality of laser diodes 81 and one of the plurality of collimator lenses 82. The plurality of recesses 114 are arranged so as to correspond to one of the plurality of laser diodes 81 and one of the plurality of collimator lenses 82.

[0041] The plurality of apertures 113 and the plurality of recesses 114 are formed so as to be arranged vertically on the side surface portion 112 of the housing 110. Therefore, the plurality of collimator lenses 82 and the plurality of laser diodes 81 are attached so as to be arranged vertically on the side surface portion 112 of the housing 110. As a result, the lateral space of the optical scanning device 1 is reduced.

[0042] Each of the plurality of apertures 113 is an opening that emits light. In the present embodiment, each of the plurality of apertures 113 is a horizontally elongated rectangular opening (through hole) extending in the horizontal direction, but it may be circular, elliptical, or the like. Each of the plurality of apertures 113 is provided on the optical axis of the collimator lens 82.

[0043] In the present embodiment, the aperture 113 has a tapered shape in which the width decreases as it moves away from the collimator lens 82. That is, the inner surface of the opening is inclined so that the width decreases as it moves away from the collimator lens 82. Therefore, it is possible to suppress stray light from entering the recess 114 from the aperture 113. Note that the aperture 113 tapers not only in terms of its width but also in terms of its height.

[0044] More specifically, the tapered shape of the aperture 113 forms a straight line in a cross-sectional view (see FIGS. 8 and 10). In other words, the tapered shape of the aperture 113 forms an inclined plane. Therefore, the tapered shape can be easily formed.

[0045] The recess 114 includes a plurality of first recesses 114a and a second recess 114b adjacent to the plurality of first recesses 114a. Each of the plurality of first recesses 114a has a shape in which a corresponding one of the collimator lenses 82 can be inserted along the optical axis of the corresponding one of the collimator lenses 82. Note that the first recess 114a constitutes a cylindrical through hole, and the diameter of the through hole is larger than the diameter of the collimator lens 82. The second recess 114b is a common recess for the plurality of first recesses 114a. A plurality of light source holders 120 are fitted into the second recess 114b. Each of the plurality of light source holders 120 has a through hole 121. Specifically, the light source holders 120a, 120b, 120c, and 120d each have through holes 121a, 121b, 121c, and 121d, respectively. A corresponding one of the plurality of laser diodes 81 is inserted into each of the plurality of through holes 121.

[0046] The plurality of first recesses 114a are each adjacent to a plurality of apertures 113. Specifically, first recess 114a-1, first recess 114a-2, first recess 114a-3, and first recess 114a-4 are adjacent to apertures 113a, 113b, 113c, and 113d, respectively. The second recess 114b is adjacent to first recess 114a-1, first recess 114a-2, first recess 114a-3, and first recess 114a-4. In other words, the spaces formed by the plurality of apertures 113, the plurality of first recesses 114a, and the second recess 114b communicate with each other.

[0047] Consider the case of viewing the recess 114 in the direction of insertion of each of the plurality of collimator lenses 82. In this case, the second recess 114b positioned in front of the recess 114 is larger than each of first recess 114a-1, first recess 114a-2, first recess 114a-3, and first recess 114a-4 positioned deeper in the recess 114. That is, when viewing the recess 114 along the optical axis direction of each of the plurality of collimator lenses 82, the second recess 114b is larger than each of the plurality of first recesses 114a. Therefore, it is easy to insert each of the plurality of collimator lenses 82 into the recess 114 up to near a corresponding one of the plurality of apertures 113.

[0048] On the side surface portion 112 of the housing 110, one of a plurality of convex portions (ribs) 115 is provided around each of the plurality of apertures 113 so as to protrude toward the inside of the housing 110. Specifically, convex portions (ribs) 115a, 115b, 115c, 115d are provided on the side surface portion 112 of the housing 110 so as to surround apertures 113a, 113b, 113c, 113d, 113e, respectively. Each of the plurality of convex portions (ribs) 115 abuts against a corresponding one of the plurality of collimator lenses 82. Therefore, each of the plurality of convex portions (ribs) 115 maintains the position of each of the plurality of collimator lenses 82 in the optical axis direction. Accordingly, the position of each of the plurality of collimator lenses 82 in the optical axis direction can be easily determined.

[0049] In this embodiment, for example, when the convex portion (rib) 115a is viewed along the optical axis direction of the aperture 113a, it is an annular protrusion provided so as to surround the optical axis of the collimator lens 82a. Therefore, the collimator lens 82a can be held more stably without inhibiting the progress of the parallel light transmitted through the collimator lens 82a. However, the shape of the convex portion (rib) 115a may be any shape. The convex portion (rib) 115a may be constituted by a plurality of separated protrusions.

[0050] The collimator lens 82a generates parallel light from the light emitted from the laser diode 81a. The collimator lens 82a is provided such that its optical axis passes through the aperture 113a. The surface of the collimator lens 82a facing each aperture 113a is a convex curved surface. The surface of the collimator lens 82a facing the laser diode 81a side is a flat surface. The parallel light generated by the collimator lens 82a is narrowed by the aperture 113a, passes through, and proceeds toward the integrated lens 83.

[0051] Each of the plurality of laser diodes 81 includes a terminal for receiving power supply. Each of the plurality of laser diodes 81 is attached to a corresponding one of the plurality of light source holders 120.

[0052] Each of the plurality of light source holders 120 is mounted in the second recess 114b of the housing 110. Each of the plurality of light source holders 120, specifically, the light source holders 120a, 120b, 120c, 120d, has a plurality of through holes 121, specifically, the through holes 121a, 121b, 121c, 121d. One corresponding laser diode 81 of the plurality of laser diodes 81 is inserted into each of the plurality of through holes 121. The terminals of each of the plurality of laser diodes 81 protrude outside the housing 110 from one opening of the corresponding one through hole 121.

[0053] The light emitting surface of each of the plurality of laser diodes 81 faces a corresponding flat surface of one of the plurality of collimator lenses 82. Each of the plurality of light source holders 120 is fitted into the second recess 114b of the housing 110 such that the light emitted from a corresponding one of the plurality of laser diodes 81 passes through a corresponding one of the plurality of collimator lenses 82. The plurality of laser diodes 81 as the plurality of light sources are arranged so as to face the plurality of collimator lenses 82, and are provided so as to emit light along the optical axes of the plurality of collimator lenses 82. Therefore, the plurality of apertures, the plurality of first recesses 114a, and the laser diodes 81 as the plurality of light sources are provided so as to be arranged vertically on the side surface portion 112.

[0054] According to the optical scanning device 1 of the present embodiment, each of the plurality of collimator lenses 82 is directly inserted into a corresponding one of the recesses 114, specifically, a corresponding one of the plurality of first recesses 114a. Therefore, for example, a lens holder for fitting the collimator lens 82a into the first recess 114a-1 is not required. Accordingly, the number of parts of the optical scanning device 1 can be reduced by the number of lens holders.

[0055] Note that, as long as each of the plurality of collimator lenses 82 and the first recess 114a are attached by a fitting without using any auxiliary members, they may be attached by any of clearance fitting, interference fitting, or shrink fitting.

[0056] In the present embodiment, each of the plurality of collimator lenses 82 is inserted into a corresponding one of the plurality of first recesses 114a so as to slightly protrude from the inside of a corresponding one of the plurality of first recesses 114a to the inside of the second recess 114b. According to this, it becomes easy to insert each of the plurality of collimator lenses 82 into a corresponding one of the plurality of first recesses 114a, and it also becomes easy to take out.

[0057] Also, in the present embodiment, each of the plurality of light source holders 120 and the corresponding one of the plurality of collimator lenses 82 are provided with a predetermined distance D (for example, 2 mm to 3 mm) therebetween. According to this, it is possible to suppress damage caused by each of the plurality of collimator lenses 82 coming into contact with the corresponding one of the plurality of light source holders 120.

[0058] FIG. 18 is an enlarged view showing a state in which a collimator lens 82, which is an example of a lens, is inserted into the first recess 114a of the housing 110 of the optical scanning device 1 according to the present embodiment. FIG. 19 is an enlarged side view of the main part on the outside of the housing 110 of the optical scanning device 1 according to the present embodiment. FIG. 20 is an enlarged perspective view of the main part on the outside of the housing 110 of the optical scanning device 1 according to the present embodiment.

[0059] As can be seen from FIGS. 18 to 20, for example, the first recess 114a-1 is provided with notches Na, Nb, and Nc. Each of the notches Na and Nc constitutes a depression into which an adhesive for fixing the collimator lens 82a to the first recess 114a-1 is injected. On the other hand, the notch Nb is a recess for inserting a jig when removing the collimator lens 82a from the first recess 114a-1.

Description of Reference Numerals

[0060] 1 Optical Scanning Device 81, 81a, 81b, 81c, 81d Laser Diode (an example of a light source) 82, 82a, 82b, 82c, 82d Collimator Lens (an example of a lens) 110 Housing 111 Bottom Surface Portion 112 Side Surface Portion 113, 113a, 113b, 113c, 113d Aperture 114 Recess 114a, 114a-1, 114a-2, 114a-3, 114a-4 First Recess 114b Second Recess 115, 115a, 115b, 115c, 115d Protrusion (Rib) Light source holders 120, 120a, 120b, 120c, 120d

Claims

1. A light source, a lens through which the light emitted from the light source passes, and a housing in which a first recess into which the lens is inserted along the optical axis of the lens and an aperture provided on the optical axis of the lens are formed. An optical scanning device.

2. The housing has a convex portion provided around the aperture and contacting the lens. The optical scanning device according to claim 1.

3. The convex portion is an annular protrusion provided so as to surround the optical axis when the aperture is viewed along the direction in which the optical axis extends. The optical scanning device according to claim 2.

4. The aperture has a tapered shape in which the width becomes narrower as it moves away from the lens. The optical scanning device according to claim 1.

5. In the cross-sectional view of the aperture, the tapered shape forms a straight line. The optical scanning device according to claim 4.

6. The aperture and the recess are integrally formed in the housing. The optical scanning device according to claim 1.

7. A second recess adjacent to the first recess is provided in the housing. When the first recess is viewed along the direction of the optical axis, the second recess is larger than the first recess. The optical scanning device according to claim 1.

8. The lens is inserted into the first recess so as to protrude from the first recess to the second recess. The optical scanning device according to claim 7.

9. The housing, a bottom surface portion, including a side surface portion rising from the bottom surface portion The side surface portion a plurality of the apertures a plurality of the first recesses a plurality of lenses inserted into the plurality of the first recesses and a plurality of light sources arranged to face the plurality of lenses and provided to emit light along the optical axes of the plurality of lenses The plurality of apertures, the plurality of the first recesses, and the plurality of the light sources are provided to be arranged vertically on the side surface portion The optical scanning device according to claim 1.

10. further comprising a light source holder mounted on the housing and holding the light source The light source holder and the lens are provided at a predetermined distance The optical scanning device according to claim 1.

11. The first recess forms a columnar through hole The diameter of the through hole is larger than the diameter of the lens The optical scanning device according to claim 1.

12. An image forming apparatus including the optical scanning device according to any one of claims 1 to 11.

Images