OPTICAL SCANNER AND IMAGE FORMING APPARATUS INCLUDING THE SAME

An optical scanner includes a scanning optical system, a housing, and a pressing and retaining member. The housing includes a retaining portion, a support portion that is formed to be opposed to the retaining portion, and an engaged portion to be engaged with an engaging portion. The pressing and retaining member includes a main body including the engaging portion and at least one pressing portion. In a first state where the engaging portion is engaged with the engaged portion, the at least one pressing portion presses the optical element toward the retaining portion. While the pressing and retaining member shifts from a second state where the engaging portion is not engaged with the engaged portion to the first state, a distal end of the at least one pressing portion passes beyond a boundary between the retaining portion and the optical element and abuts on a part of the housing.

INCORPORATION BY REFERENCE

This application is based upon and claims the benefit of priority from the corresponding Japanese Patent Application No. 2023-042596 (filed on Mar. 17, 2023), the entire contents of which are incorporated herein by reference.

BACKGROUND

The present disclosure relates to an optical scanner that forms a latent image on a scanning target surface by exposure scanning and an image forming apparatus including the same, such as a copy machine, a printer, a facsimile, or a multi-functional peripheral equipped with functions of these apparatuses.

Conventionally, in an optical scanner used in an image forming apparatus, a light beam emitted from a light source such as a laser diode passes through a collimator lens, a cylindrical lens, and an aperture to become incident on a deflector such as a polygon mirror so as to be deflected, and then passes through a scanning lens to be guided to a photosensitive drum (an image carrier) where the light beam is used for exposure scanning on a surface of the photosensitive drum so that an electrostatic latent image is formed thereon.

Furthermore, in a case where the light beam that has passed through the scanning lens cannot be directly guided to the photosensitive drum due to limitations on a layout of the image forming apparatus, generally adopted is a configuration in which a folding mirror is used to reflect the light beam. Typically, a pressing and retaining member such as a leaf spring is used to press a reflection surface of the folding mirror against a seating surface formed in a housing of the optical scanner so that positioning and securing of the folding mirror are achieved.

SUMMARY

An optical scanner according to an aspect of the present disclosure includes a scanning optical system, a housing, and a pressing and retaining member and exposes to light a surface of an image carrier so as to form thereon an electrostatic latent image with attenuated electrostatic charge. The scanning optical system scans a light beam and guides the light beam onto the image carrier. The housing includes a retaining portion that retains an optical element as a component of the scanning optical system. The pressing and retaining member presses the optical element so as to retain the optical element to the retaining portion. The pressing and retaining member includes a main body and a pressing portion that is connected to the main body and presses the optical element retained to the retaining portion toward the retaining portion. The housing includes a support portion that is formed to be opposed to the retaining portion and supports the main body and an engaged portion to be engaged with an engaging portion formed in the main body. In a first state where the pressing and retaining member is inserted between the retaining portion and the support portion so that the engaging portion is engaged with the engaged portion, the pressing portion presses the optical element toward the retaining portion. While the pressing and retaining member shifts from a second state where the engaging portion is not engaged with the engaged portion to the first state, a distal end of the pressing portion passes beyond a boundary between the retaining portion and the optical element and abuts on a part of the housing.

DETAILED DESCRIPTION

The following describes embodiments of the present disclosure with reference to the appended drawings.FIG.1is a schematic sectional view showing an overall configuration of an image forming apparatus100in which an optical scanner5of the present disclosure is mounted.FIG.2is an enlarged view of a vicinity of an image forming portion Pa shown inFIG.1.

The image forming apparatus100shown inFIG.1is a so-called tandem color printer and has a configuration described below. That is, in a main body of the image forming apparatus100, four image forming portions Pa, Pb, Pc, and Pd are arranged in order from upstream in a conveyance direction (a left side inFIG.1). The image forming portions Pa to Pd are provided so as to correspond to images of four different colors (magenta, cyan, yellow, and black) and sequentially form images of magenta, cyan, yellow, and black, respectively, by individually performing steps of charging, exposure, development, and transfer.

In the image forming portions Pa to Pd, photosensitive drums1a,1b,1c, and1dare arranged, respectively, to carry visible images (toner images) of the respective colors. Moreover, an intermediate transfer belt8that rotates in a counterclockwise direction inFIG.1is provided adjacently to the image forming portions Pa to Pd. Toner images formed respectively on the photosensitive drums1ato1dare sequentially transferred on the intermediate transfer belt8moving while abutting on the photosensitive drums1ato1dand then are transferred collectively on a sheet S as an example of a recording medium in a secondary transfer unit9. Moreover, the toner images are fixed on the sheet S in a fixing portion13, and then the sheet S is discharged from the main body of the image forming apparatus100. An image forming process with respect to the photosensitive drums1ato1dis executed while the photosensitive drums1ato1dare rotated in a clockwise direction inFIG.1.

The sheet S on which the toner images are to be transferred is contained in a sheet cassette16provided in a lower part of the main body of the image forming apparatus100and is conveyed to the secondary transfer unit9via a paper feed roller12aand a registration roller pair12b. A seam-free (seamless) belt is mainly used as the intermediate transfer belt8.

Next, a description is given of the image forming portions Pa to Pd. While the following describes the image forming portion Pa in detail, the image forming portions Pb to Pd are also basically similar in configuration to the image forming portion Pa, and duplicate descriptions thereof, therefore, are omitted. As shown inFIG.2, around the photosensitive drum1a, a charging device2a, a developing device3a, and a cleaning device7aare arranged along a drum rotation direction (a clockwise direction inFIG.2), and a primary transfer roller6ais disposed to face the photosensitive drum1avia the intermediate transfer belt8. Furthermore, a belt cleaning unit19is disposed upstream from the photosensitive drum1ain a rotation direction of the intermediate transfer belt8so as to be opposed to a tension roller11via the intermediate transfer belt8.

Next, a description is given of an image forming procedure performed in the image forming apparatus100. Upon an input of a user's instruction to start image formation, first, the photosensitive drums1ato1dare started to rotate by a main motor (not shown), and surfaces of the photosensitive drums1ato1dare each uniformly charged by a charging roller20of a corresponding one of the charging devices2ato2d. Then, a light beam (a laser light beam) emitted from the optical scanner5is applied to the surfaces of the photosensitive drums1ato1dso that electrostatic latent images corresponding to an image signal are formed on the photosensitive drums1ato1d.

The developing devices3ato3dare filled with prescribed amounts of toners of the respective colors of magenta, cyan, yellow, and black, respectively. In a case where a percentage of the toners in two-component developers filled in the developing devices3ato3dfalls below a preset value due to after-mentioned toner image formation, the developing devices3ato3dare replenished with fresh supplies of toners from toner containers4ato4d, respectively. The toners in the developers are supplied onto the photosensitive drums1ato1deach by a developing roller21of a corresponding one of the developing devices3ato3dand electrostatically adhere thereto. Thus, there are formed toner images corresponding to the electrostatic latent images formed by exposure from the optical scanner5.

Further, by the primary transfer rollers6ato6d, an electric field is applied at a prescribed transfer voltage between themselves and the photosensitive drums1ato1d, respectively, and thus the toner images of magenta, cyan, yellow, and black on the photosensitive drums1ato1dare primarily transferred on the intermediate transfer belt8. These images of the four different colors are formed in a prescribed positional relationship previously determined for prescribed full-color image formation. After that, residual toners remaining on the surfaces of the photosensitive drums1ato1dare removed each by a cleaning blade22and a rubbing roller23of a corresponding one of the cleaning devices7ato7din preparation for subsequent formation of new electrostatic latent images.

As a driving roller10is driven to rotate by a belt drive motor (not shown), the intermediate transfer belt8starts to rotate in the counterclockwise direction, and then the sheet S is conveyed at a prescribed timing from the registration roller pair12bto the secondary transfer unit9provided adjacently to the intermediate transfer belt8, in which a toner image is transferred thereon. The sheet S on which the toner images have been transferred is conveyed to the fixing portion13. A residual toner remaining on a surface of the intermediate transfer belt8is removed by the belt cleaning unit19.

The sheet S conveyed to the fixing portion13is subjected to heat and pressure by a fixing roller pair13a, and thus the toner images are fixed on a surface of the sheet S to form a prescribed full-color image thereon. A conveyance direction of the sheet S on which the full-color image has been formed is controlled by a branch portion14branching off in a plurality of directions, and the sheet S is directly (or after being conveyed to a duplex conveyance path18and thus subjected to duplex printing) discharged to a discharge tray17by a discharge roller pair15.

Next, a description is given of the optical scanner5.FIG.3is a sectional side view showing an internal configuration of an optical scanner5according to an embodiment of the present disclosure. As shown inFIG.3, the optical scanner5includes a housing48. The housing48includes a main body48aand a lid48b. A polygon mirror45is disposed on a bottom surface of the main body48a. In this embodiment, the polygon mirror45is formed of a rotary polyhedral mirror having a regular polygonal shape, with a plurality of deflection surfaces (reflection surfaces) formed on side surfaces thereof, and is driven to rotate at a prescribed speed by a polygon motor38. The polygon motor38is secured to a motor support plate39that is secured to the bottom surface of the main body48a.

In the housing48, there are disposed a laser light source, a collimator lens, an aperture, a cylindrical lens (none of which are shown), a first scanning lens46a, second scanning lenses47ato47d, and plane mirrors49ato49c. The first scanning lens46aand each of the second scanning lenses47ato47dhave an fe characteristic and thus form an image of a corresponding one of laser light beams D1to D4deflected and reflected by the polygon mirror45on a corresponding one of the photosensitive drums1ato1d. Furthermore, the plane mirrors49ato49care disposed on optical paths of the laser light beams D1to D4extending from the polygon mirror45to the photosensitive drums1ato1d.

A description is given of an operation of scanning the laser light beams D1and D2performed by the optical scanner5configured as above. First, the laser light beams D1and D2emitted from the laser light source are made into substantially parallel light fluxes by the collimator lens and are adjusted to have a prescribed optical path width by the aperture. Next, the laser light beams D1and D2thus made into the substantially parallel light fluxes are made incident on the cylindrical lens. The laser light beams D1and D2thus made incident on the cylindrical lens are emitted directly as the parallel light fluxes in a main scanning cross section and in a converged state in a sub-scanning direction and are formed into linear images on the deflection surfaces of the polygon mirror45. At this time, in order to facilitate separation of the optical paths of the two laser light beams D1and D2deflected by the polygon mirror45, the laser light beams D1and D2are configured to become incident on the deflection surfaces at different angles from each other in the sub-scanning direction.

The laser light beams D1and D2made incident on the polygon mirror45are deflected by the polygon mirror45at a constant angular velocity and then are deflected by the first scanning lens46aat a constant velocity. The laser light beams D1and D2that have passed through the first scanning lens46aare folded by corresponding ones of the plane mirrors49adisposed respectively on the optical paths thereof, and the laser light beam D1becomes incident on the second scanning lens47aso as to be deflected thereby at a constant velocity, while the laser light beam D2becomes incident on the second scanning lens47bso as to be deflected thereby at a constant velocity. Further, the laser light beams D1and D2thus deflected at a constant velocity are folded by corresponding ones of the plane mirrors49cas most downstream mirrors disposed respectively on the optical paths thereof and pass through windows70aand70b, respectively, which are formed in the lid48bcovering an opening of the main body48a, so as to be distributed to the photosensitive drums1aand1b, respectively.

In a similar manner, after passing through the collimator lens, the aperture, and the cylindrical lens, the laser light beams D3and D4emitted from the laser light source are also deflected by the polygon mirror45at a constant angle velocity and deflected by the first scanning lens46aat a constant velocity. The laser light beam D3that has passed through the first scanning lens46ais folded twice by a corresponding one of the plane mirrors49aand the plane mirror49bdisposed on the optical path thereof and then becomes incident on the second scanning lens47cso as to be deflected at a constant velocity, while the laser light beam D4that has passed through the first scanning lens46abecomes incident on the second scanning lens47dso as to be deflected at a constant velocity. Moreover, the laser light beam D3is folded by a corresponding one of the plane mirrors49cas a most downstream mirror, while the laser light beam D4is folded by a corresponding one of the plane mirrors49a, and the laser light beams D3and D4pass through windows70cand70dformed in the lid48b, respectively, so as to be distributed to the photosensitive drums1cand1d, respectively.

The polygon mirror45, the first scanning lens46a, the second scanning lenses47ato47d, and the plane mirrors49ato49cconstitute a scanning optical system that scans the laser light beams D1to D4and guides them onto the photosensitive drums1ato1d, respectively.

FIG.4is a perspective view of a pressing spring50(a pressing and retaining member) for pressing and retaining a first scanning lens46ain a housing48of an optical scanner5according to a first embodiment of the present disclosure. The pressing spring50is formed by bending a metal plate and includes a spring main body51, a first pressing portion52and a second pressing portion53.

The spring main body51is supported to a spring support portion61(seeFIG.5andFIG.6) of the housing48. The spring main body51has an engaging hole51a(an engaging portion) formed at a lower end thereof. The engaging hole51aengages with an engaged portion60d(seeFIG.6) of a lens retaining portion60.

The first pressing portion52is bent from the spring main body51at a first bent part50aabove the engaging hole51aand is further bent at a second bent part50bin a direction inverse to a direction of bending at the first bent part50a, thus being formed in an L shape as viewed sideways. The first pressing portion52is connected to the spring main body51so as to be elastically deformable, with the first bent part50aserving as a fulcrum of bending. A first pressure contact point52ahaving a hemispherical shape is formed substantially at a center of the first pressing portion52in a longitudinal direction thereof. The first pressing portion52includes an extension52bformed of a distal end (upper) part thereof beyond the first pressure contact point52aextending toward the second pressing portion53.

The second pressing portion53is bent from the spring main body51at a third bent part50cat an upper end of the spring main body51and extends in the same direction as an extending direction of the first pressing portion52. The second pressing portion53is bent in an inverted V shape as viewed sideways at a fourth bent part50d. The second pressing portion53is connected to the spring main body51so as to be elastically deformable, with the third bent part50cserving as a fulcrum of bending. A second pressure contact point53ahaving a V shape as viewed sideways is formed in a distal end part of the second pressing portion53. The second pressing portion53includes a proximal end53bcloser to the spring main body51than the second pressure contact point53aand an extension53ccloser to a distal end thereof than the second pressure contact point53a. The proximal end53band the extension53care flush with each other.

The pressing spring50has a slit50eformed to extend in an up-down direction from the first bent part50ato a neighborhood of the second pressure contact point53avia the third bent part50cand the fourth bent part50d. The slit50eis formed by cutting and raising the first pressing portion52from the spring main body51.

FIG.5is a partial sectional view of a vicinity of the lens retaining portion60in the housing48. WhileFIG.5shows a structure for retaining the first scanning lens46aon one side in a longitudinal direction thereof, a similar structure thereto is provided also on the other side of the first scanning lens46ain the longitudinal direction.

As shown inFIG.5, the lens retaining portion60is provided in a main body48a(seeFIG.3) of the housing48. The lens retaining portion60has an L shape as viewed sideways and includes a first retaining surface60aopposed to a light incidence surface (a left side surface inFIG.5) of the first scanning lens46aand a second retaining surface60bopposed to a lower surface of the first scanning lens46a. The second retaining surface60bhas a protrusion60cformed thereon. The engaged portion60dis formed below the second retaining surface60b.

The spring support portion61is provided in the main body48a. The spring support portion61is opposed at a prescribed distance to the first retaining surface60aof the lens retaining portion60. The spring support portion61has an inclined surface61aformed at an upper part thereof.

The pressing spring50is inserted between a light emission surface (a right side surface inFIG.5) of the first scanning lens46aand the spring support portion61. An engaging hole51aof the pressing spring50engages with the engaged portion60d, and thus positioning of the pressing spring50with respect to the main body48ais achieved (a first state). The first pressing portion52is in contact at the first pressure contact point52awith the light emission surface of the first scanning lens46a. The second pressing portion53is in contact at the second pressure contact point53awith an upper surface of the first scanning lens46a.

That is, by a biasing force of the first pressing portion52of the pressing spring50, the light incidence surface (the left side surface inFIG.5) of the first scanning lens46ais pressed against the first retaining surface60a. Furthermore, by a biasing force of the second pressing portion53of the pressing spring50, the lower surface of the first scanning lens46ais pressed against the protrusion60cof the second retaining surface60b.

According to this configuration, by use of the single pressing spring50, the first scanning lens46acan be retained to the first retaining surface60aand the second retaining surface60bof the lens retaining portion60. Accordingly, without the need to increase the number of pressing springs50used, the first scanning lens46acan be retained stably.

Next, a description is given of a method for securing the first scanning lens46aby using the pressing spring50in the optical scanner5of the first embodiment.FIG.6is a partial sectional view of the vicinity of the lens retaining portion60in the housing48of the optical scanner5of the first embodiment, illustrating a state where the pressing spring50is inserted between the first scanning lens46aand the spring support portion61.

In a case of securing the first scanning lens46aby using the pressing spring50, first, as shown inFIG.6, the light incidence surface and the lower surface of the first scanning lens46aare brought into contact with the first retaining surface60aand the second retaining surface60b(the protrusion60c) of the lens retaining portion60, respectively. As the pressing spring50is inserted, in this state, from above between the first scanning lens46aand the spring support portion61, the spring main body51of the pressing spring50slides downward along the inclined surface61aof the spring support portion61. Furthermore, the first pressure contact point52aof the first pressing portion52contacts the light emission surface of the first scanning lens46a.

Thus, by the biasing force of the first pressing portion52, the first scanning lens46ais brought into pressure contact with the first retaining surface60a. At this time, the second pressing portion53is not in contact with the upper surface of the first scanning lens46a. Furthermore, the engaging hole51aof the spring main body51is not engaged with the engaged portion60dof the lens retaining portion60(a second state).

As the pressing spring50is inserted further downward from the state shown inFIG.6, as shown inFIG.7, a distal end of the extension53cof the second pressing portion53contacts an upper surface60eof the lens retaining portion60. At this time, the second pressure contact point53aof the second pressing portion53is not in contact with the upper surface of the first scanning lens46a.

As the pressing spring50is inserted further downward from a state shown inFIG.7, as shown inFIG.8, the second pressure contact point53aof the second pressing portion53contacts the upper surface of the first scanning lens46a. Thus, by the biasing force of the second pressing portion53, the first scanning lens46ais brought into pressure contact with the second retaining surface60b(the protrusion60c).

As the pressing spring50is inserted further downward from a state shown inFIG.8, the engaging hole51aformed at the lower end of the spring main body51engages with the engaged portion60dof the lens retaining portion60, and there is brought about a state (the first state) shown inFIG.5where the first scanning lens46ais pressed and retained to the lens retaining portion60by the pressing spring50.

In this embodiment, when the pressing spring50is inserted between the lens retaining portion60and the spring support portion61, before the second pressure contact point53aof the second pressing portion53abuts on the upper surface of the first scanning lens46a, the extension53cabuts on the upper surface60eof the lens retaining portion60. Thus, in retaining the first scanning lens46ato the lens retaining portion60by using the pressing spring50, the second pressure contact point53aand the extension53cof the second pressing portion53can be prevented from entering a gap between the first retaining surface60aof the lens retaining portion60and the first scanning lens46a. Accordingly, there is no possibility that cracking or chipping occurs at an edge (a corner) of the first scanning lens46aor that the first scanning lens46ais disposed in an inclined manner.

Furthermore, in a case where the first retaining surface60aof the lens retaining portion60is substantially perpendicular as in this embodiment, from the viewpoint of preventing the second pressing portion53from entering the gap between the first retaining surface60aand the first scanning lens46a, it is difficult in terms of a mold structure to form a projection projecting from the first retaining surface60a. It is, therefore, particularly effective to adopt a relationship between the pressing spring50and the lens retaining portion60in the configuration of this embodiment.

FIG.9is a partial sectional view of a vicinity of a lens retaining portion60in a housing48of an optical scanner5according to a second embodiment of the present disclosure, illustrating a state where a first scanning lens46ais pressed and retained by a pressing spring50. In this embodiment, a second pressing portion53of the pressing spring50is configured differently from that in the first embodiment. To be more specific, a proximal end53band an extension53cof the second pressing portion53are not flush with each other, and the extension53cis bent in a direction toward an upper surface60eof the lens retaining portion60. Other portions of the pressing spring50are configured similarly to those in the first embodiment.

Next, a description is given of a method for securing the first scanning lens46aby using the pressing spring50in the optical scanner5of the second embodiment.FIG.10is a partial sectional view of the vicinity of the lens retaining portion60in the housing48of the optical scanner5of the second embodiment, illustrating a state where the pressing spring50is inserted between the first scanning lens46aand a spring support portion61.

In a case of securing the first scanning lens46aby using the pressing spring50, first, as shown inFIG.10, a light incidence surface and a lower surface of the first scanning lens46aare brought into contact with a first retaining surface60aand a second retaining surface60b(a protrusion60c) of the lens retaining portion60, respectively. As the pressing spring50is inserted, in this state, from above between the first scanning lens46aand the spring support portion61, a spring main body51of the pressing spring50slides downward along an inclined surface61aof the spring support portion61. Furthermore, a first pressure contact point52aof a first pressing portion52contacts a light emission surface of the first scanning lens46a.

Thus, by a biasing force of the first pressing portion52, the first scanning lens46ais brought into pressure contact with the first retaining surface60a. At this time, the second pressing portion53is not in contact with an upper surface of the first scanning lens46a. Furthermore, an engaging hole51aof the spring main body51is not engaged with an engaged portion60dof the lens retaining portion60(a second state).

As the pressing spring50is inserted further downward from the state shown inFIG.10, as shown inFIG.11, a distal end of the extension53cof the second pressing portion53contacts the upper surface60eof the lens retaining portion60. At this time, a second pressure contact point53aof the second pressing portion53is not in contact with the upper surface of the first scanning lens46a.

As the pressing spring50is inserted further downward from a state shown inFIG.11, as shown inFIG.12, the second pressure contact point53aof the second pressing portion53contacts the upper surface of the first scanning lens46a. Thus, by a biasing force of the second pressing portion53, the first scanning lens46ais brought into pressure contact with the second retaining surface60b(the protrusion60c).

As the pressing spring50is inserted further downward from a state shown inFIG.12, the engaging hole51aformed at a lower end of the spring main body51engages with the engaged portion60dof the lens retaining portion60, and there is brought about the state (the first state) shown inFIG.9where the first scanning lens46ais pressed and retained to the lens retaining portion60by the pressing spring50.

Also in this embodiment, similarly to the first embodiment, when the pressing spring50is inserted between the lens retaining portion60and the spring support portion61, before the second pressure contact point53aof the second pressing portion53abuts on the upper surface of the first scanning lens46a, the extension53cabuts on the upper surface60cof the lens retaining portion60. Thus, the second pressure contact point53aand the extension53cof the second pressing portion53can be prevented from entering a gap between the first retaining surface60aof the lens retaining portion60and the first scanning lens46a. Accordingly, there is no possibility that cracking or chipping occurs at an edge (a corner) of the first scanning lens46aor that the first scanning lens46ais disposed in an inclined manner.

Furthermore, since the extension53cis bent in the direction toward the upper surface60eof the lens retaining portion60, when the pressing spring50is inserted between the lens retaining portion60and the spring support portion61, the distal end of the extension53cis likely to contact the upper surface60eof the lens retaining portion60. This makes it possible to shorten the extension53ccompared with that in the first embodiment.

In addition, the present disclosure is not limited to the foregoing embodiments and can be variously modified without departing from the spirit of the present disclosure. For example, while the foregoing embodiments have described a configuration in which the first scanning lens46ais pressed and retained by the pressing spring50, an optical element pressed and retained by the pressing spring50is not limited to the first scanning lens46aand may also be each of the second scanning lenses47ato47dor each of the plane mirrors49ato49c. In a case where each of the plane mirrors49ato49cis pressed and retained by the pressing spring50, it is possible to effectively suppress cracking or chipping that might occur at an edge (a corner) of the each of the plane mirrors49ato49cdue to contact by the second pressing portion53.

Furthermore, a configuration of disposing the components constituting the scanning optical system in the housing48is not limited to that shown inFIG.3and may also be, for example, a configuration in which the polygon mirror45is disposed substantially at a center of the housing48, and one of two first scanning lenses46aand the second scanning lenses47aand47bare disposed to be opposed to the other of the two first scanning lenses46aand the second scanning lenses47cand47dvia the polygon mirror45.

Furthermore, while the foregoing description uses a tandem color printer as an example of the image forming apparatus100in which the optical scanner5is mounted, the present disclosure is not limited to the color printer and is applicable also to an electrophotographic color image forming apparatus such as a color copy machine or a facsimile or an electrophotographic monochrome image forming apparatus such as a monochrome printer or a monochrome multi-functional peripheral.

The present disclosure is usable in an optical scanner that forms a latent image on a scanning target surface by exposure scanning. Through the use of the present disclosure, it is possible to provide an optical scanner capable of preventing an optical element retained by using a pressing and retaining member from being subjected to cracking or chipping or from being disposed in an inclined manner irrespective of an angle at which the optical element is installed, and an image forming apparatus including the same.