JP7330917B2 - Optical scanning device and image forming device - Google Patents

Description

The present invention relates to an image forming apparatus such as an optical scanning device, a copying machine, a multifunction machine, a printer, and a facsimile machine.

An optical scanning device generally includes a beam detector that receives a light beam from a light source (for example, a laser diode element), and an optical path between the light source and the beam detector that directs light toward the beam detector. a condensing lens for condensing the beam. In such an optical scanning device, the beam detector detects the main scanning start timing of a light beam emitted from a light source and deflected and scanned in a predetermined main scanning direction by a deflection scanning member.

JP 2008-257194 A

By the way, it is conceivable to share an optical member (for example, a condenser lens) in an optical scanning device with an image forming apparatus or an optical scanning device of each model of electronic equipment (for example, each model of image forming device) provided with an optical scanning device. However, the optical member cannot be shared by each model of the image forming apparatus or the optical scanning device, and a dedicated optical member is sometimes used for each model of the image forming device or the optical scanning device.

Regarding this point, for example, Patent Document 1 describes an optical scanning device in which an imaging lens as an optical member is positioned by a protrusion provided at the center in the longitudinal direction of the imaging lens. However, there is no mention of common use in the image forming apparatus or the optical scanning apparatus.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an optical scanning device and an image forming apparatus in which an optical member can be shared by various types of image forming apparatuses or optical scanning apparatuses.

In order to solve the above problems, the present invention provides the following optical scanning device and image forming apparatus.

(1) Optical scanning device
An optical scanning device according to the present invention is an optical scanning device that includes an optical member , and includes a beam detector that receives a light beam emitted from a light source and deflected and scanned in a predetermined main scanning direction by a deflection scanning member. the optical member includes a first installation portion installed on a housing of the optical scanning device; and a second installation portion installed on the housing at a location different from the first installation portion; The first installation portion and the second installation portion are provided with a first engaging portion and a second engaging portion, respectively, which are locked by a positioning locking portion provided on the housing. In the width direction perpendicular to both the height direction and the optical axis direction, which is the direction of the optical axis of the optical member, the first engaging portion is locked by the locking portion so that the first installation portion is a first distance between the first engaging portion and the optical axis when installed in a housing; A second distance between the second engaging portion and the optical axis when installed in a housing is different, and the optical member can be arranged in a plurality of different arrangement positions in the housing. A supporting portion for supporting the optical member is provided, the supporting portion supports the optical member so as to be arranged at a plurality of different arrangement positions in the width direction, the supporting portion includes the locking portion, and the optical member includes the locking portion. The member is a condensing lens for condensing the light beam from the deflection scanning member toward the beam detection section .

( 2 ) Image Forming Apparatus An image forming apparatus according to the present invention includes the optical scanning device according to the present invention.

According to the present invention, although the configuration is simple, the optical member can be shared by various types of image forming apparatuses or optical scanning apparatuses.

1 is a schematic cross-sectional view of an image forming apparatus according to an exemplary embodiment viewed from the front; FIG. 2 is a perspective view of the front side of an optical scanning device in the image forming apparatus shown in FIG. 1 as viewed from the upper right; FIG. 3 is a perspective view of the rear side of the optical scanning device shown in FIG. 2 as viewed from the upper left; FIG. FIG. 3 is a perspective view of the optical scanning device shown in FIG. 2 with a top cover removed, viewed from above the front side; 5 is a plan view showing the optical scanning device shown in FIG. 4; FIG. FIG. 3 is an exploded perspective view showing a state in which a lower cover is removed from the optical scanning device; 3 is a perspective view showing an example of a deflection scanning unit in the optical scanning device; FIG. FIG. 5 is a perspective view showing another example of a deflection scanning unit in the optical scanning device; FIG. 2 is a plan view showing an example of the configuration of an optical system for a normal size of recording paper in an optical scanning device; FIG. 10 is a plan view showing another example of the configuration of the optical system for the normal size specification of the recording paper in the optical scanning device; FIG. 2 is a plan view showing an example of the configuration of an optical system for a special size of recording paper in an optical scanning device; FIG. 10 is a plan view showing another example of the configuration of the optical system for the special size specification of the recording paper in the optical scanning device; FIG. 8C is a plan view showing the configuration of the optical system in the optical scanning device shown in FIGS. 8A to 8D ; It is a schematic diagram for demonstrating the beam detection structure of a surface light reception type. It is a schematic diagram for demonstrating the beam detection structure of a back surface light reception type. It is a top view which shows the support part part in a housing|casing. FIG. 12D is a perspective view of the state before the support portion of the housing of the condenser lens is attached to the position shown in FIG. 12C , viewed from above on the light beam incident side; FIG. 12D is a perspective view of the state after the support portion of the housing of the condenser lens is attached to the position shown in FIG. 12C , viewed from above on the light beam incident side; FIG. 4 is a plan view of a condenser lens arranged at a first optical axis direction arrangement position and a first width direction arrangement position in a support portion of a housing; FIG. 13D is a perspective view of the state before the support portion of the housing of the condenser lens is attached to the position shown in FIG. 13C , viewed from above on the light beam incident side; FIG. 13D is a perspective view of the state after the support portion of the housing of the condenser lens is attached to the position shown in FIG. 13C , viewed from above on the light beam incident side; FIG. 4 is a plan view of a condenser lens arranged at a first optical axis direction arrangement position and a second width direction arrangement position in a support portion of a housing; FIG. 14C is a perspective view of the state before attachment of the supporting portion of the housing of the condenser lens to the position shown in FIG. 14C , viewed from above on the light beam emitting side; FIG. 14D is a perspective view of the state after the support portion of the housing of the condenser lens is attached to the position shown in FIG. 14C , viewed from above on the light beam emission side; FIG. 10 is a plan view of a condenser lens arranged at a second optical axis direction arrangement position and a first width direction arrangement position in a support portion of a housing; FIG. 15B is a perspective view of the state before the support portion of the housing of the condenser lens is attached to the position shown in FIG. 15C , viewed from above on the light beam emission side; FIG. 15D is a perspective view of the state after the support portion of the housing of the condenser lens is attached to the position shown in FIG. 15C , viewed from above on the light beam emission side. FIG. 10 is a plan view of a condensing lens arranged at a second optical axis direction arrangement position and a second width direction arrangement position in a support portion of a housing;

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments according to the present invention will be described below with reference to the drawings. In the following description, the same parts are given the same reference numerals. Their names and functions are also the same. Therefore, a detailed description thereof will not be repeated.

[Image forming apparatus]
FIG. 1 is a schematic cross-sectional view of an image forming apparatus 100 according to the present embodiment as viewed from the front. In the figure, the symbol X indicates the depth direction, the symbol Y the horizontal direction, and the symbol Z the vertical direction.

Image forming apparatus 100 according to the present embodiment is a monochrome image forming apparatus. The image forming apparatus 100 performs image forming processing according to image data read by the image reading apparatus 1 or image data transmitted from the outside. Note that the image forming apparatus 100 may be a color image forming apparatus that forms multicolor and monochromatic images on the paper P. FIG.

The image forming apparatus 100 includes a document feeder 108 and an image forming apparatus main body 110 . An image forming unit 102 and a sheet conveying system 103 are provided in the image forming apparatus main body 110 .

The image forming section 102 includes an optical scanning device 200 (optical scanning unit), a developing unit 2 , a photosensitive drum 3 acting as an electrostatic latent image carrier, a cleaning section 4 , a charging device 5 and a fixing unit 7 . The paper transport system 103 also includes a paper feed tray 81 , a manual paper feed tray 82 , a discharge roller 31 and a discharge tray 14 .

An image reading device 1 for reading an image of a document G is provided on the upper portion of the image forming apparatus main body 110 . The image reading apparatus 1 includes a document table 107 on which a document G is placed. A document feeding device 108 is provided above the document table 107 . In the image forming apparatus 100, the image of the document G read by the image reading apparatus 1 is sent to the image forming apparatus main body 110 as image data, and the image is recorded on the paper P. FIG.

The image forming apparatus main body 110 is provided with a paper transport path S1. The paper feed tray 81 or the manual paper feed tray 82 supplies the paper P to the paper transport path S1. The paper transport path S<b>1 guides the paper P to the discharge tray 14 via the transfer roller 10 and the fixing unit 7 . The fixing unit 7 fixes the toner image formed on the paper P to the paper P by heating. Pickup rollers 11a and 11b, a transport roller 12a, a registration roller 13, a transfer roller 10, a heat roller 71 and a pressure roller 72 in the fixing unit 7, and a discharge roller 31 are arranged near the paper transport path S1.

In the image forming apparatus 100 , the paper P supplied from the paper feed tray 81 or the manual paper feed tray 82 is conveyed to the registration rollers 13 . Next, the paper P is conveyed to the transfer roller 10 at the timing at which the registration roller 13 aligns the paper P with the toner image on the photosensitive drum 3 . The toner image on the photosensitive drum 3 is transferred onto the paper P by the transfer roller 10 . After that, the paper P passes through the heat roller 71 and pressure roller 72 in the fixing unit 7 and is discharged onto the discharge tray 14 via the transport roller 12 a and the discharge roller 31 . When the image is formed not only on the front side of the paper P but also on the back side, the paper P is conveyed in the reverse direction from the ejection roller 31 to the reverse paper conveyance path S2. The paper P passes through the reversing conveying rollers 12b to 12b, the front and back of the paper P is reversed, and is led to the registration rollers 13 again. After a toner image is formed and fixed on the back surface of the paper P, the paper P is ejected toward the ejection tray 14 in the same manner as on the front surface.

[Optical scanning device]
FIG. 2 is a perspective view of the front side of the optical scanning device 200 in the image forming apparatus 100 shown in FIG. 1 as viewed from the upper right. FIG. 3 is a perspective view of the rear side of the optical scanning device 200 shown in FIG. 2 as viewed from the upper left. FIG. 4 is a perspective view of the optical scanning device 200 shown in FIG. 2 with the top cover 202 removed, viewed from above the front side. FIG. 5 is a plan view showing the optical scanning device 200 shown in FIG. FIG. 6 is an exploded perspective view of the optical scanning device 200 with the lower cover 204 removed. 7A and 7B are perspective views showing one example and another example of the deflection scanning unit 220 in the optical scanning device 200, respectively. 8A and 8B are plan views respectively showing one example and another example of the configuration of the optical system for the normal size (A3 size) specification of the recording paper (paper P) in the optical scanning device 200. FIG. 8C and 8D are plan views showing an example and another example of the configuration of the optical system for the special size (SRA3 size) of the recording paper (paper P) in the optical scanning device 200, respectively. FIG. 9 is a plan view showing the configuration of the optical system in the optical scanning device 200 shown in FIGS. 8A to 8D. Further, FIG. 10A is a schematic diagram for explaining a front-surface-receiving beam detection structure, and FIG. 10B is a schematic diagram for explaining a back-surface-receiving beam detection structure.

In the optical scanning device 200, the size in the main scanning direction X1 of the reflecting surface 223a of the deflection scanning member 223 (second deflection scanning member 2232) of the deflection scanning unit 220 (2202) shown in FIGS. 7B, 8C, 8D, and 9 is larger than the size in the main scanning direction X1 of the reflecting surface 223a of the deflection scanning member 223 (first deflection scanning member 2231) of the deflection scanning unit 220 (2201) shown in FIGS. 7A, 8A, 8B, and 9. ing. The optical scanning device 200 is deflected by the deflection scanning unit 220 (2201) shown in FIGS. 7A, 8A, 8B and 9 and the deflection scanning unit 220 (2202) shown in FIGS. 7B, 8C, 8D and 9. The deflection scanning units 220 (2201, 2202) can be replaced by replacing the lower lids 204, 204 provided with the scanning units 220 (2201, 2202). The configurations shown in FIGS. 7A, 8A, 8B and 9 and the configurations shown in FIGS. 7B, 8C, 8D and 9 will be described together below.

The optical scanning device 200 includes a housing 201 , an incident optical system 210 , a deflection scanning unit 220 (deflection scanning section), and an emission optical system 230 .

The incident optical system 210 includes a light source 211 (laser diode element), a collimator lens 212, an aperture member 213, a cylindrical lens 214, and a reflecting mirror 215 for light source. The light source 211 emits a light beam L (laser beam). The collimator lens 212 converts the light beam L from the light source 211 into substantially parallel light and irradiates the aperture member 213 with the parallel light. The aperture member 213 constricts the light beam L from the collimator lens 212 and irradiates it onto the cylindrical lens 214 . The cylindrical lens 214 converges the light beam L from the aperture member 213 only in the sub-scanning direction and condenses it on the reflecting surface 223a of the deflection scanning member 223 (polygon mirror) via the reflecting mirror 215 for light source. The light source reflecting mirror 215 guides the light beam L from the cylindrical lens 214 to the reflecting surface 223a of the deflection scanning member 223 (polygon mirror).

The deflection scanning unit 220 includes a deflection scanning substrate 221, a deflection scanning motor 222 (polygon motor), and a deflection scanning member 223 (rotating polygon mirror). The deflection scanning board 221 is fixed to the plane (upper surface) side of the lower lid 204 with a plurality of fixing members (screws) SC to SC. A deflection scanning motor 222 is provided on the deflection scanning substrate 221 . A deflection scanning member 223 (first deflection scanning member 2231, second deflection scanning member 2232) is fixed to the rotating shaft 222a of the deflection scanning motor 222 (first deflection scanning motor 2221, second deflection scanning motor 2222). . The deflection scanning member 223 deflects and scans the light beam L from the light source reflection mirror 215 in a predetermined main scanning direction X1.

The output optical system 230 includes an fθ lens 231, a beam detection reflecting mirror 232, a condenser lens 233 (beam detection lens) which is an example of an optical member, and a beam detection unit 234 [Beam Detect sensor (BD sensor)]. and

The fθ lens 231 is elongated in the main scanning direction X1. The f.theta. The beam detection reflecting mirror 232 guides the light beam L deflected and scanned by the reflecting surface 223 a of the deflection scanning member 223 to the condenser lens 233 .

Considering the detection accuracy of the beam detection unit 234, the first optical path length from the deflection scanning member 223 to the object to be scanned (photosensitive drum 3) and the second optical path length from the deflection scanning member 223 to the beam detection unit 234 It is necessary to make the beam diameter of the light beam L irradiated by the photosensitive drum 3 and the beam diameter of the light beam L irradiated by the beam detector 234 equal or approximately equal. However, in this example, the first optical path length is longer than the second optical path length. Therefore, the light beam L from the reflecting mirror 232 for beam detection is condensed on the beam detection section 234 using the condenser lens 233 . As a result, even if the first optical path length is longer than the second optical path length, the beam diameter of the light beam L at the photosensitive drum 3 and the beam diameter of the light beam L at the beam detection unit 234 are made equal or substantially equal. can be made equal.

The beam detector 234 detects the main scanning start timing of the light beam L (image writing start timing). The optical scanning device 200 further includes a substrate 240 (light source and beam detector substrate). In the optical scanning device 200, a front light receiving substrate 241 (single-sided substrate) or a rear light receiving substrate 242 (double-sided substrate or multilayer substrate) is mounted as the substrate 240 depending on the model of the image forming apparatus 100. FIG. A light source 211 and a beam detector 234 are provided on the substrate 240 (241, 242).

The housing 201 has a rectangular bottom plate 201a and four side plates 201b to 201e surrounding the bottom plate 201a. The housing 201 is provided with a deflection scanning chamber 203 (see FIGS. 4 to 6) that covers the deflection scanning unit 220 . An opening 203a (see FIG. 6) is provided in the deflection scanning chamber 203 portion of the bottom plate 201a. The opening 203a is closed by a lower lid 204, and the lower lid 204 is fixed to the bottom (lower) side of the bottom plate 201a with a plurality of fixing members (screws) SC to SC. A deflection scanning unit 220 is arranged on the lower cover 204 , and the deflection scanning unit 220 is accommodated in the deflection scanning chamber 203 by fixing the lower cover 204 to the bottom plate 201 a. As a result, the deflection scanning unit 220 can be replaced by replacing the lower cover 204 provided with the deflection scanning unit 220 with another lower cover 204 provided with the deflection scanning unit 220 .

The light beam L reflected by the light source reflection mirror 215 enters the deflection scanning chamber 203 through the first window 203b (see FIG. 5) formed in the deflection scanning chamber 203. As shown in FIG. Further, the light beam L scanned by the deflection scanning member 223 is emitted to the outside of the deflection scanning chamber 203 through the first window portion 203b. A first dustproof glass plate 235 (transparent body) is provided in the first window portion 203b. As a result, it is possible to effectively prevent dust and other unwanted substances from entering the deflection scanning chamber 203 . The light beam L that has passed through the f.theta. A second dustproof glass plate 236 (transparent body) is provided in the second window portion 201f. As a result, it is possible to effectively prevent unwanted substances such as dust from entering the housing 201 .

The board 240 is a flat printed board and has a circuit for driving the light source 211 . The substrate 240 is fixed to the outside of the side plate 201 d of the housing 201 opposite to the fθ lens 231 so that the light emitting portion of the light source 211 and the light receiving portion of the beam detector 234 face the inside of the housing 201 . The emitting portion of the light source 211 and the light receiving portion of the beam detector 234 face the inside of the housing 201 through respective openings (not shown) formed in the side plate 201d. Thereby, the light source 211 can emit the light beam L from the emitting portion toward the collimator lens 212 inside the housing 201 . The beam detection unit 234 can receive the light beam L from the condenser lens 233 in the housing 201 at the light receiving unit.

The deflection scanning board 221 is a flat printed board and has a circuit for driving the deflection scanning motor 222 . A deflection scanning motor 222 is fixed on the deflection scanning substrate 221 , and a central portion of a deflection scanning member 223 is connected and fixed to a rotating shaft 222 a of the deflection scanning motor 222 . The deflection scanning member 223 is rotationally driven by a deflection scanning motor 222 .

Next, the optical path through which the light beam L from the light source 211 is incident on the photosensitive drum 3 will be described.

The light beam L from the light source 211 passes through the collimator lens 212 to be substantially parallel light, condensed by the aperture member 213, passes through the cylindrical lens 214, enters the light source reflection mirror 215, is reflected, and is deflected. It is incident on the reflecting surface 223 a of the scanning member 223 . The deflection scanning member 223 is rotated in a predetermined rotation direction R at a constant angular velocity by the deflection scanning motor 222, and the light beam L is successively reflected by each reflecting surface 223a, and the light beam L is repeatedly reflected in the main scanning direction X1 at a constant angular velocity. Deflect. The fθ lens 231 converges the light beam L to a predetermined beam diameter on the surface of the photosensitive drum 3 in both the main scanning direction X1 and the sub-scanning direction. Further, the fθ lens 231 converts the light beam L, which is deflected at a constant angular velocity in the main scanning direction X1 by the deflection scanning member 223, so that the light beam L moves at a constant linear velocity on the photosensitive drum 3. FIG. This allows the light beam L to repeatedly scan the surface of the photosensitive drum 3 in the main scanning direction X1.

Further, the beam detection unit 234 receives the light beam L reflected by the beam detection reflection mirror 232 immediately before main scanning (writing) of the photosensitive drum 3 is started. The beam detector 234 receives the light beam L just before main scanning of the surface of the photosensitive drum 3 starts, and outputs a BD signal indicating the timing just before main scanning starts. The start timing of the main scanning of the photosensitive drum 3 on which the toner image is formed is set according to the BD signal, and writing of the light beam L corresponding to the image data is started. Then, the two-dimensional surface (peripheral surface) of the photosensitive drum 3 that is rotationally driven and charged is scanned by the light beam L, and each electrostatic latent image is formed on the surface of the photosensitive drum 3 .

By the way, as the incident angle of the light beam L incident on the first dust-proof glass plate 235 is closer to a right angle, the light transmittance can be improved. In this regard, since the light beam L is scanned in the main scanning direction X1, for example, if the first dust-proof glass plate 235 is provided along the longitudinal direction W of the fθ lens 231, the following problems will occur. There is That is, on the first dust-proof glass plate 235, the light beam L (deflected Since the light beam L) directed from the scanning member 223 to the beam detection unit 234 is too inclined with respect to the first dust-proof glass plate 235, the light transmittance is deteriorated.

In this regard, in the present embodiment, the first dust-proof glass plate 235 is inclined with respect to the longitudinal direction W of the fθ lens 231 so as to face the beam detection section 234 side. By doing so, it is possible not only to avoid deterioration of the light transmittance of the light beam L with respect to the first dust-proof glass plate 235 in the scanning area α, It is possible to avoid deterioration of the light transmittance of the first dust-proof glass plate 235 . Also, the deflection scanning board 221 is arranged parallel or substantially parallel to the first dust-proof glass plate 235 .

[Regarding this embodiment]
In the optical scanning device 200 according to the present embodiment, the beam detector 234 detects the main scanning start timing of the light beam L emitted from the light source 211 and deflected and scanned in the main scanning direction X1 by the deflection scanning member 223 .

By the way, depending on the type of the beam detection unit 234, the incident position in the optical axis direction S (incident direction M1 in which the light beam L is incident), which is the direction of the optical axis N, may differ. For example, the beam detection unit 234 includes a front-surface-receiving beam detection structure and a back-reception-type beam detection structure. In the present embodiment, it is possible to attach a plurality of types of beam detectors 234 having mutually different incident positions in the incident direction M1 in which the light beam L is incident.

The surface light receiving substrate 241 (substrate 240) has a conductor pattern formed only on one surface (surface). As shown in FIG. 10A, the beam detection unit 234 provided on the front surface light receiving substrate 241 (substrate 240) is, for example, a light receiving unit 234a (light receiving surface ) faces the surface 240a of the surface light receiving substrate 241 (single-sided substrate). Conductor patterns are formed on both surfaces (front surface and rear surface) of the rear light receiving substrate 242 (substrate 240). As shown in FIG. 10B, the beam detection unit 234 provided on the back light receiving substrate 242 (substrate 240) is, for example, a light receiving unit on the back surface 240b of the back light receiving substrate 242 [double-sided board or multilayer board (four-layer board)]. 234a may be mounted facing away from back surface 240b. In this case, when the front light receiving substrate 241 (single-sided substrate) and the back light receiving substrate 242 (double-sided substrate or multilayer substrate) are attached at the same position in the incident direction M1, the beam detection section provided on the front light receiving substrate 241 234 and the beam detector 234 provided on the rear light-receiving substrate 242, the position of the light-receiving part 234a in the incident direction M1 is different. For this reason, the focal distance d1 of the light beam L from the condenser lens 233 to the light receiving part 234a of the beam detection part 234 in the front surface reception type beam detection structure shown in FIG. 10A and the back surface reception type beam detection structure shown in FIG. The focal distance d2 of the light beam L from the condenser lens 233 to the light receiving part 234a of the beam detecting part 234 differs from the focal distance d2 (d1>d2). Then, the focal position of the condenser lens 233 is at the focal length d1 or the focal length d2 to the beam detection unit 234 in either one of the front light receiving type beam detection structure and the back light receiving type beam detection structure. , the focal position of the condenser lens 233 in the other beam detection structure will not match, and the beam detection accuracy of the beam detection unit 234 will deteriorate.

Further, image formation of each model having different sizes of scanning areas α (α1, α2) (see FIGS. 8A to 9 ) from the scanning start position to the scanning end position of the light beam L deflected and scanned by the deflection scanning member 223. When the optical scanning device 200 is shared with the device, for example, image formation of each model with different specifications of the size of the recording paper (paper P) [A3 size (297 mm × 420 mm) and SRA3 size (320 mm × 450 mm)]. When the optical scanning device 200 is shared with the apparatus, the optical scanning device 200 needs to be provided with a plurality of types of deflection scanning members 223 each having a reflecting surface 223a with a different size in the main scanning direction X1.

In this case, from the viewpoint of miniaturization of the housing 201, the reflecting mirror (232) is provided near the outside of the scanning area α (α1, α2), so that the light is reflected by the first scanning area α1 and the second scanning area α2. The arrangement position of the mirror (232) is changed. Then, the angle of incidence of the light beam L on the reflecting mirror (232) changes, so it is necessary to change the mirror arrangement angles θ (θ1, θ2). In this example, the second scanning area α2 is larger than the first scanning area α1. Specifically, the first scanning area α1 is the scanning area by the first deflection scanning member 2231, and the width (width of the image area) on the scanning surface of the object to be scanned (photosensitive drum 3) is 310 mm. The second scanning area α2 is a scanning area by the second deflection scanning member 2232, and has a width (image area width) of 330 mm on the scanning surface of the object to be scanned (photosensitive drum 3). Therefore, the arrangement position (second arrangement position) of the reflection mirror (232) in the second scanning area α2 is outside the arrangement position (first arrangement position) of the reflection mirror (232) in the first scanning area α1. To position. Then, the arrangement position of the reflecting mirror (232) and the mirror arrangement angle θ (θ1, θ2) change between the first scanning region α1 and the second scanning region α2.

Regarding these points, in the optical scanning device 200 according to the present embodiment, a plurality of types of deflection scanning members 223 to 223 having reflecting surfaces 223a to 223a of different sizes in the main scanning direction X1 are used as the deflection scanning member 223. considered to be replaceable. By doing so, it is possible to provide the optical scanning device 200 with a plurality of types of deflection scanning members 223 to 223 each having reflecting surfaces 223a to 223a of different sizes in the main scanning direction X1. In this example, the first deflection scanning member 2231 shown in FIG. 7A has a reflective surface 223a with a predetermined first size in the main scanning direction X1. The second deflection scanning member 2232 shown in FIG. 7B has a reflecting surface 223a of a predetermined second size larger than the first deflection scanning member 2231 shown in FIG. 7A and the first size in the main scanning direction X1.

By the way, the optical path length from the light source 211 to the beam detector 234 depends on the permissible performance level of the optical members (especially the condenser lens 233) (especially the deviation of the optical axis) between the first arrangement position and the second arrangement position of the reflecting mirror (232). allowable level), it is difficult to maintain the performance of the optical scanning device 200 unless the positional relationship of the condenser lens 233 is changed.

In this regard, in the optical scanning device 200 according to the present embodiment, the housing 201 is provided with a support portion 250 (see FIG. 5) that supports the condenser lens 233 so that it can be arranged at a plurality of different arrangement positions. there is The supporting portion 250 is concentrated at a plurality of different arrangement positions in the optical axis direction S (the incident direction M1 of the light beam L to the condensing lens 233) and the width direction T (the orthogonal direction M2 orthogonal to the incident direction M1). It supports the optical lens 233 so that it can be arranged. Here, the width direction T is the direction of the installation side to the housing 201 and the opposite side to the installation side, which is the height direction H [the rotation axis direction of the deflection scanning member 223 (polygon mirror)] and the optical axis direction S. is a direction orthogonal to both

FIG. 11 is a plan view showing the supporting portion 250 portion of the housing 201. As shown in FIG. 12A and 12B are perspective views of the light beam L incidence side before and after the support 250 of the housing 201 of the condenser lens 233 is attached to the position shown in FIG. 12C, as viewed from above. 12C is a plan view of the collective lens 233 arranged at the first optical axis direction arrangement position E1 and the first width direction arrangement position F1 in the support portion 250 of the housing 201. FIG. In FIG. 12C, the first engaging portion 237a and the locking portion 205a are shown not to be in contact with each other, but they are actually in contact with each other. 13C, contact between the first engaging portion 237b and the locking portion 205b in FIG. 14C, and contact between the second engaging portion 238a and the locking portion 205b in FIG. 15C. The same applies to contact between 238b and locking portion 205b.

13A and 13B are perspective views of the light beam L incidence side before and after the support portion 250 of the housing 201 of the condenser lens 233 is attached to the position shown in FIG. 13C, as viewed from above. FIG. 13C is a plan view of the collective lens 233 arranged at the first optical axis direction arrangement position E1 and the second width direction arrangement position F2 in the support portion 250 of the housing 201. FIG.

14A and 14B are perspective views of the light beam L emitting side before and after the support portion 250 of the housing 201 of the condenser lens 233 is attached to the position shown in FIG. 14C, as viewed from above. FIG. 14C is a plan view of the condenser lens 233 arranged at the second optical axis direction arrangement position E2 and the first width direction arrangement position F1 in the support portion 250 of the housing 201. FIG.

15A and 15B are perspective views of the light beam L emitting side before and after the support portion 250 of the housing 201 of the condenser lens 233 is attached to the position shown in FIG. 15C, as viewed from above. FIG. 15C is a plan view of the condenser lens 233 arranged at the second optical axis direction arrangement position E2 and the second width direction arrangement position F2 in the support portion 250 of the housing 201. FIG.

The condenser lens 233 has a first installation portion 2331 and a second installation portion 2332 . The first installation section 2331 is installed on the housing 201 of the optical scanning device 200 . The second installation portion 2332 is installed on the housing 201 at a location different from the first installation portion 2331 . A first engaging portion 237 (237a, 237b) and a second engaging portion 238 (238a, 238b) are provided on the first installation portion 2331 and the second installation portion 2332, respectively. The first engaging portions 237 ( 237 a, 237 b ) and the second engaging portions 238 ( 238 a, 238 b ) are engaged with positioning engaging portions 205 ( 205 a, 205 b ) provided on the housing 201 .

In the width direction T perpendicular to both the height direction H and the optical axis direction S, the first engaging portions 237 (237a, 237b) engage with the locking portions 205 (205a, 205b). When the first installation portion 2331 is installed on the housing 201, the first installation portion 2331 is installed in the housing 201 at a distance between the central portion in the width direction T of the first engaging portion 237 (237a, 237b) and the optical axis N (the center of curvature). 1 distance D1 (see FIGS. 12C and 14C), and the second engaging portion 238 (238a, 238b) is locked to the locking portion 205 (205a, 205b) so that the second installation portion 2332 is installed in the housing 201. The second distance D2 (see FIGS. 13C and 15C) between the central portion in the width direction T of the second engaging portion 238 (238a, 238b) and the optical axis N (the center of curvature) when the . By doing so, the positional relationship of the condenser lens 233 can be changed by the first engaging portions 237 (237a, 237b) and the second engaging portions 238 (238a, 238b). Here, the optical axis can be a straight line connecting the center of curvature of the lens surface on the incident side of the light beam L in the lens portion 233 a of the condenser lens 233 and the center of curvature of the lens surface on the exit side. In this example, the first engaging portions 237a and 273b are provided on the incident side and the emitting side of the light beam L in the condenser lens 233, respectively. The locking portions 205a and 205b are provided on the incident side and the emitting side of the light beam L with respect to the condenser lens 233 in the housing 201, respectively.

Thus, according to this embodiment, the positional relationship of the condenser lens 233 can be changed by the first engaging portion 237 and the second engaging portion 238, so the configuration is simple. Moreover, since only the work of arranging the condenser lens 233 is performed, no particular adjustment work is required. Further, the condenser lens 233 can be arranged at a plurality of positions, whereby the condenser lenses 233 supported at the plurality of arrangement positions are all common lenses [same shape or approximately the same shape (same size or approximately lenses of the same dimensions)]. Therefore, the optical member can be shared by each model of image forming apparatus or optical scanning apparatus.

In the present embodiment, the condenser lens 233 has the first engaging portion 237 (237a, 237b) and the second engaging portion 238 (238a, 238b) aligned with the optical axis N (center of curvature) in the height direction H. located on one side and the other of the boundary.

By doing so, by rotating the condenser lens 233 about the optical axis N by 180 degrees, the arrangement position of the condenser lens 233 can be easily changed.

In the present embodiment, the condenser lens 233 is configured so that the first engaging portions 237 (237a, 237b) and the second engaging portions 238 (238a, 238b) are bounded by the optical axis N (center of curvature) in the width direction T. located on one side and the other side of the

By doing so, the first engaging portions 237 (237a, 237b) and the second engaging portions 238 (238a, 238b) of the condenser lens 233 are locked to the locking portions 205a, 205b on one side in the width direction T. On the other hand, it is possible to secure a space for providing a structure for supporting the condenser lens 233 on the other side.

(First embodiment)
In this embodiment, the condensing lens 233 includes the locking portions 205 (205a and 205b) in the housing 201, the first engaging portions 237 (237a and 237b) in the first installation portion 2331, and the second installation portion 2332. are engaged with the second engaging portions 238 (238a, 238b) in the concave and convex portions.

By doing so, the locking portion 205 (205a, 205b), the first engaging portion 237 (237a, 237b), and the second engaging portion 238 (238a, 238b) are engaged with the housing 201 in an uneven manner. The condensing lens 233 can be reliably locked by

In the present embodiment, the condensing lens 233 has the locking portions 205 (205a, 205b) on the housing 201 that are convex portions, and the first engaging portions 237 (237a, 237b) on the first installation portion 2331 and the second Both of the second engaging portions 238 (238a, 238b) in the two installation portions 2332 are concave portions.

By doing so, the condenser lens 233 can be arranged in the housing without the first engaging portions 237 (237a, 237b) and the second engaging portions 238 (238a, 238b) interfering with other members. can.

In this example, the locking portion 205 (205a, 205b) is recessed in the optical axis direction S, and the locking portion 205 (205a, 205b) protrudes in the optical axis direction S. However, it is not limited to this, and the locking portions 205 (205a, 205b) may be recessed in the height direction H, and the locking portions 205 (205a, 205b) may protrude in the height direction H. Alternatively, the engaging portion 205 may protrude in the optical axis direction S, and the engaging portion 205 may be recessed in the optical axis direction S. Alternatively, the engaging portion 205 may protrude in the height direction H and may be recessed in the optical axis direction S. A combination of these may also be used.

In the present embodiment, in the height direction H, the condenser lens 233 is configured such that the first engaging portions 237 (237a, 237b) are locked by the locking portions 205 (205a, 205b), and the first installation portion 2331 is The third distance d3 (see FIGS. 12B and 14B) between the housing 201 and the optical axis N (the center of curvature) when installed in the housing 201, and the second engaging portion 238 (238a, 238b) A fourth distance d4 between the housing 201 and the optical axis N (center of curvature) when the second installation portion 2332 is installed in the housing 201 by being locked by the locking portions 205 (205a, 205b) (See FIGS. 13B and 15B).

By doing so, the condenser lens 233 can be attached to the same or different type of optical scanning device 200 having the same type of optical system (the light beam L is at the same height position).

In the present embodiment, the condenser lens 233 is configured such that the first engaging portions 237 (237a, 237b) are locked by the locking portions 205 (205a, 205b) in the height direction H, thereby A third distance d3 between the housing 201 and the optical axis N (the center of curvature) when the housing 2331 is installed in the housing 201, 205a, 205b) and the fourth distance d4 between the housing 201 and the optical axis N (the center of curvature) when the second installation portion 2332 is installed in the housing 201 is different. good.

By doing so, the condenser lens 233 can be attached to different types of optical scanning devices 200 having different types of optical systems (different height positions of the light beam L).

In this embodiment, the condenser lens 233 includes a lens portion 233a and an outer frame portion 233b provided on the outer periphery of the lens portion 233a. A first engaging portion 237 (237a, 237b) and a second engaging portion 238 (238a, 238b) are provided on the outer frame portion 233b.

In this way, the light beam L can be condensed by the lens portion 233a. 237 (237a, 237b) and second engaging portions 238 (238a, 238b) may be provided.

Here, the condensing lens 233 is formed by molding. Therefore, the condensing lens 233 is provided with a gate portion 233c (protrusion) corresponding to an injection port portion for injecting molding resin. In this example, the side opposite to the gate portion 233c of the condenser lens 233 is the first installation portion 2331, and the gate portion 233c side of the condenser lens 233 is the second installation portion 2332. As shown in FIG. Further, the housing 201 is provided with an insertion portion 201h through which the gate portion 233c is inserted when the condenser lens 233 is installed in the housing 201 . The insertion portion 201h may be a bottomed hole or a through hole as long as the installation portion of the condenser lens 233 (the second installation portion 2332 in this example) can reliably contact the housing 201 .

In the present embodiment, the condenser lens 233 has the first engaging portions 237 (237a, 237b) and the second engaging portions 238 (238a, 238b) locked to the locking portions 205 (205a, 205b). Movement in the width direction T is thereby restricted.

By doing so, the condensing lens 233 can be reliably positioned in the width direction T.

(Second embodiment)
In the present embodiment, the condenser lens 233 has a rectangular parallelepiped shape in which the length of the side in the optical axis direction S is smaller than the length of the other sides.

By doing so, the condensing lens 233 can be made compact in the optical axis direction S, and thus the size reduction of the optical scanning device 200 can be realized.

In this embodiment, the condenser lens 233 has a lens portion that has a spherical surface (convex surface) on the light beam L incident side and a toroidal surface (concave surface) on the light beam L exit side. Here, the toroidal surface is a surface that has curvature in one direction (width direction T in this example) but does not have curvature in a direction perpendicular thereto (height direction H in this example). Specifically, the curvature of the spherical surface is 0.0446 [1/mm] (curvature radius of 22.4 [mm]), and the curvature of the toroidal surface is 0.0190 [1/mm] (curvature radius of 52.6 [mm]). mm]).

By doing so, the light beam L can be focused in one direction (the width direction T in this example).

Specifically, in the present embodiment, support portion 250 in housing 201 has standing wall 250a erected from bottom surface 201g of housing 201 . Here, the bottom surface 201 g of the housing 201 includes installation surfaces corresponding to the first installation portion 2331 and the second installation portion 2332 .

Incidentally, the condenser lens 233 arranged at each arrangement position is finally fixed to the support portion 250 with an adhesive material such as an adhesive.

(Third Embodiment)
In the present embodiment, as shown in FIGS. 11 and 12A to 15C, the supporting portion 250 supports the condenser lens 233 so as to be arranged at a plurality of different arrangement positions in the width direction T (orthogonal direction M2). . The support portion 250 includes the locking portions 205 (205a, 205b).

In this way, the support part 250 supports the condenser lens 233 so that it can be arranged at a plurality of positions different from each other in the width direction T, so that the positional relationship of the condenser lens 233 in the width direction T can be changed. Thereby, the performance of the optical scanning device 200 can be maintained.

(Fourth embodiment)
In addition, in the present embodiment, the support portion 250 has a plurality of different optical axis direction arrangement positions (E1, E2) in the optical axis direction S (incident direction M1) and different positions in the width direction T (orthogonal direction M2). The condenser lens 233 is supported so as to be arranged at a plurality of widthwise arrangement positions (F1, F2).

10A and d2 shown in FIG. 10B. can be made equal or approximately equal, which effectively prevents deterioration of the beam detection accuracy of the beam detection structure. In addition, since the support portion 250 supports the condenser lens 233 in a plurality of positions different from each other in the width direction T, the positional relationship of the condenser lens 233 in the width direction T can be changed. , the performance of the optical scanning device 200 can be maintained.

12A to 15C, the supporting portion 250 includes an outer peripheral surface facing portion 251 facing the outer peripheral surfaces (233b1, 233b2) of the outer frame portion 233b, and an outer peripheral surface of the condenser lens 233. It has one or a plurality of side support portions 252 that support side surfaces (233b3, 233b4) that intersect (perpendicularly) with the outer peripheral surface (233b1, 233b2) of the portion 233b.

By doing so, the condensing lens 233 can be reliably held by the side support portion 252 .

More specifically, the support portion 250 includes a locking support portion 252a on the upstream side (hereinafter simply referred to as upstream side) in the incident direction M1 and a locking support portion 252a on the downstream side (hereinafter simply referred to as downstream side) in the incident direction M1. and a portion 252d. The side support portion 252 includes a first side support portion 252b and a second side support portion 252c on the upstream side, and a first side support portion 252e and a second side support portion 252f on the downstream side.

The locking support portions 252a and 252d include locking portions 205a at their distal ends. The first side support portion 252b and the second side support portion 252c on the upstream side support the side surface 233b3 on the upstream side of the outer frame portion 233b. The first side support portion 252e and the second side support portion 252f on the downstream side support the side surface 233b4 on the downstream side of the outer frame portion 233b.

As shown in FIGS. 12C, 13C, 14C, and 15C, the locking support portions 252a and 252d are first contact portions 2521 (2521a and 2521b) vertically or substantially vertically erected from the bottom surface 201g of the housing 201. ) (a convex curved surface along the standing direction M3). The first side support portions 252b and 252e have second contact portions 2522 (2522b and 2522e) (wall surfaces) erected vertically or substantially vertically from the bottom surface 201g of the housing 201 . Further, the second side support portions 252c and 252f have third contact portions 2523 (2523c and 2523f) (wall surfaces) erected vertically or substantially vertically from the bottom surface 201g of the housing 201. As shown in FIG. Here, the second contact portion 2522e and the third contact portion 2523f are shared with each other and are the same contact portion.

As shown in FIG. 12C, when the condenser lens 233 is arranged at the first optical axis direction arrangement position E1 and the first width direction arrangement position F1, the upstream first contact portion 2521a The condensing lens 233 is locked by the upstream first engagement portion 237a of the lens 233 . At this time, the upstream second contact portion 2522b contacts the lower side of the upstream side surface 233b3 of the condenser lens 233 (see FIG. 12B).

As shown in FIG. 13C, when the condenser lens 233 is arranged at the first optical axis direction arrangement position E1 and the second width direction arrangement position F2, the upstream first contact portion 2521a The condensing lens 233 is locked by the second engaging portion 238a on the upstream side of 233 . At this time, the upstream third contact portion 2523c contacts the lower side of the upstream side surface 233b3 of the condenser lens 233 (see FIG. 13B).

As shown in FIG. 14C, when the condenser lens 233 is arranged at the second optical axis direction arrangement position E2 and the first width direction arrangement position F1, the downstream first contact portion 2521b The condensing lens 233 is locked by the first engagement portion 237b on the downstream side of 233 . At this time, the downstream second contact portion 2522e contacts the lower side of the downstream side surface 233b4 of the condenser lens 233 (see FIG. 14B).

Further, as shown in FIG. 15C, when the condenser lens 233 is arranged at the second optical axis direction arrangement position E2 and the second width direction arrangement position F2, the downstream first contact portion 2521b The condensing lens 233 is locked by the second engaging portion 238b on the downstream side of the optical lens 233 . At this time, the downstream third contact portion 2523f contacts the lower side of the downstream side surface 233b4 of the condenser lens 233 (see FIG. 15B).

(Fifth embodiment)
By the way, in order to prevent the condensing lens 233 from collapsing, it is desirable to increase the height of the supporting portion 250 from the bottom surface 201g of the housing 201 as much as possible. On the other hand, if the height of the portion of the support portion 250 corresponding to the lens portion 233a from the bottom surface 201g of the housing 201 is too high, the optical path of the light beam L entering the condenser lens 233 is blocked.

In this regard, in the present embodiment, the support portion 250 is such that the height h1 (see FIG. 12A) of the outer peripheral surface facing portion 251 from the bottom surface 201g of the housing 201 is the lens portion 233a (at least the light beam L 12A) from the bottom surface 201g of the housing 201.

By doing so, it is possible to effectively prevent the condensing lens 233 from collapsing at the outer peripheral surface facing portion 251, and the light incident on the condensing lens 233 at the portion corresponding to the lens portion 233a in the side support portion 252. An optical path for the beam L can be secured.

(Sixth embodiment)
In the present embodiment, the position of the reflecting mirror (232) and Since the mirror arrangement angles θ (θ1, θ2) (see FIGS. 8A to 8D) change, the incident angle of the light beam L to the condenser lens 233 changes.

In this regard, in the present embodiment, the support portion 250 has one side support portion (252b, 252e) and other side support portions (252c, 252f). The support portion 250 has one first lens arrangement angle φ (φ1) (see FIGS. 12C and 14C) and another second lens arrangement angle φ (φ2) (see FIGS. 13C and 15C). . The first lens arrangement angle φ1 is the arrangement angle of the condenser lens 233 supported by one side support portion (252b, 252e) and locked by the locking portions 205 (205a, 205b). The second lens arrangement angle φ2 is the arrangement angle of the condenser lens 233 supported by the other side support portions (252c, 252f) and locked by the locking portions 205 (205a, 205b). Here, the first lens arrangement angle φ1 and the second lens arrangement angle φ2 are angles of the condenser lens 233 with respect to the reference line (in this example, the longitudinal direction W of the fθ lens 231).

As shown in FIG. 12C, the first side support portion 252b and the locking support portion 252a on the upstream side have the first lens arrangement angle φ1 at the first optical axis direction arrangement position E1 and the first width direction arrangement position F1. The condensing lens 233 is supported as follows. Specifically, in the example shown in FIG. 12C, in the condenser lens 233 having the first lens arrangement angle φ1, the lower portion of the side surface 233b3 is on the upstream side while the first engaging portion 237a is locked by the locking support portion 252a. 12B).

As shown in FIG. 13C, the second side surface support portion 252c and the locking support portion 252a on the upstream side have the second lens arrangement angle φ2 at the first optical axis direction arrangement position E1 and the second width direction arrangement position F2. The condensing lens 233 is supported as follows. Specifically, in the condenser lens 233 having the second lens arrangement angle φ2 in the example shown in FIG. 13C, the lower part of the side surface 233b3 is on the upstream side while the second engaging portion 238a is locked by the locking support portion 252a. 13B).

As shown in FIG. 14C, the first side support portion 252e and the locking support portion 252d on the downstream side have the first lens arrangement angle φ1 at the second optical axis direction arrangement position E2 and the first width direction arrangement position F1. The condensing lens 233 is supported as follows. Specifically, in the condenser lens 233 having the first lens arrangement angle φ1 in the example shown in FIG. 14C, the lower part of the side surface 233b4 is downstream when the first engaging portion 237b is locked to the locking support portion 252d. 14B).

As shown in FIG. 15C, the second side support portion 252f and the locking support portion 252d on the downstream side have the second lens arrangement angle φ2 at the second optical axis direction arrangement position E2 and the second width direction arrangement position F2. The condensing lens 233 is supported as follows. Specifically, in the condenser lens 233 having the second lens arrangement angle φ2 in the example shown in FIG. 15C , the lower part of the side surface 233b4 is downstream when the second engaging portion 238b is locked to the locking support portion 252d. is abutted on the second side support portion 252f of (see FIG. 15B).

By doing so, even if the lens arrangement angles φ (φ1, φ2) of the condenser lens 233 differ among the models of the image forming apparatuses, the condenser lens 233 can be used in common.

(Seventh embodiment)
In the present embodiment, the optical scanning device 200 can replace a plurality of types of deflection scanning members 223 to 223 having reflecting surfaces 223a to 223a of different sizes in the main scanning direction X1 as the deflection scanning member 223. there is

By doing so, it is possible to provide the optical scanning device 200 with a plurality of types of deflection scanning members 223 to 223 each having reflecting surfaces 223a to 223a of different sizes in the main scanning direction X1. In this example, the first deflection scanning member 2231 shown in FIG. 7A has a reflective surface 223a with a predetermined first size in the main scanning direction X1. The second deflection scanning member 2232 shown in FIG. 7B has a reflecting surface 223a of a predetermined second size larger than the first size in the main scanning direction X1 of the first deflection scanning member 2231 shown in FIG. 7A.

(Eighth embodiment)
In the first to seventh embodiments described above, the optical member is the condensing lens 233 that converges the light beam L from the deflecting scanning member 223 toward the beam detection unit 234, thereby concentrating the optical member. It can be suitably used for the optical lens 233 .

(Other embodiments)
In the first to eighth embodiments, the size (depth in this example) of the first engaging portion 237 (237a, 237b) and the second engaging portion 238 (238a, 238b) in the optical axis direction S is Either may be equal, or at least two may be different. Further, the contact positions of the first side support portion 252b and the second side support portion 252c on the upstream side and the locking portion 205a with the condenser lens 233 may be aligned in the optical axis direction S, or at least two It may be shifted. Similarly, the contact positions of the first side support portion 252e and the second side support portion 252f on the downstream side and the engaging portion 205b with the condenser lens 233 may be aligned in the optical axis direction S, or at least two positions may be aligned. It can be off the top. Moreover, it is preferable that the first side support portion 252b and the second side support portion 252c are provided on one side and the other side in the width direction T with the optical axis N as a reference, respectively. The first side support portion 252b and the second side support portion 252c on the upstream side and the locking portion 205a are arranged on one side and the other side in the width direction T with respect to the optical axis N of the supported condenser lens 233, respectively. is preferably provided in In addition, the first side support portion 252e and the second side support portion 252f on the downstream side and the locking portion 205b are respectively arranged on one side and the other side in the width direction T with the optical axis N of the supported condenser lens 233 as a reference. It is preferably provided on both sides.

The present invention is not limited to the embodiments described above, but can be implemented in various other forms. Therefore, the embodiment concerned is merely an example in all respects, and should not be construed in a restrictive manner. The scope of the present invention is indicated by the claims and is not restricted by the text of the specification. Furthermore, all modifications and changes within the equivalence range of claims are within the scope of the present invention.

100 Image forming apparatus 200 Optical scanning device 210 Incidence optical system 220 Deflecting scanning unit 230 Emission optical system 231 fθ lens 232 Reflecting mirror for beam detection 233 Condensing lens 2331 First installation section 2332 Second installation section 233a Lens section 233b Outer frame section 233b3 Side surface 233b4 Side surface 233c Gate portion 234 Beam detection portion 234a Light receiving portion 237 First engaging portion 238 Second engaging portion 240 Board 250 Supporting portion 250a Standing wall 251 Peripheral surface facing portion 252 Side supporting portion 2521 First contacting portion 2522 Second contact portion 2523 Third contact portion 252a Lock support portion 252b First side support portion 252c Second side support portion 252d Lock support portion 252e First side support portion 252f Second side support portion D1 First distance D2 Second distance E1 First optical axis direction arrangement position E2 Second optical axis direction arrangement position F1 First width direction arrangement position F2 Second width direction arrangement position G Document H Height direction L Light beam M1 Incident direction M2 Orthogonal direction M3 Standing Setting direction N Optical axis R Rotational direction S Optical axis direction T Width direction W Longitudinal direction X1 Main scanning direction d1 Focal length d2 Focal length d3 Third distance d4 Fourth distance α Scanning area α1 First scanning area α2 Second scanning area θ Mirror placement angle φ Lens placement angle φ1 First lens placement angle φ2 Second lens placement angle

Claims (17)

An optical scanning device comprising an optical member ,
a beam detector for receiving a light beam emitted from a light source and deflected and scanned in a predetermined main scanning direction by a deflection scanning member;
The optical member includes a first installation portion installed in a housing of the optical scanning device, and a second installation portion installed in the housing at a location different from the first installation portion,
The first installation portion and the second installation portion are provided with a first engaging portion and a second engaging portion, respectively, which are locked by a positioning locking portion provided on the housing,
In the width direction perpendicular to both the height direction of the optical member and the optical axis direction, which is the direction of the optical axis of the optical member, the first engaging portion is engaged with the engaging portion to form the first optical member. A first distance between the first engaging portion and the optical axis when the installation portion is installed in the housing; different from the second distance between the second engaging portion and the optical axis when the installation portion is installed in the housing,
The housing is provided with a support that supports the optical member so that it can be arranged at a plurality of different arrangement positions,
The support portion supports the optical member so as to be arranged at a plurality of different arrangement positions in the width direction,
The support portion includes the locking portion,
The optical scanning device , wherein the optical member is a condensing lens for condensing the light beam from the deflection scanning member toward the beam detection section. The optical scanning device according to claim 1,
The optical scanning device , wherein the first engaging portion and the second engaging portion of the optical member are positioned on one side and the other side of the optical axis in the height direction. The optical scanning device according to claim 1 or claim 2,
The optical scanning device , wherein the first engaging portion and the second engaging portion of the optical member are positioned on one side and the other side of the optical axis in the width direction. The optical scanning device according to any one of claims 1 to 3,
The engaging portion of the housing is engaged with the first engaging portion of the first installation portion of the optical member and the second engaging portion of the second installation portion of the optical member. Optical scanner . The optical scanning device according to claim 4,
The optical scanning device , wherein the engaging portion of the housing is a convex portion, and both the first engaging portion and the second engaging portion of the optical member are concave portions. The optical scanning device according to any one of claims 1 to 5,
In the height direction, the optical member is aligned with the housing and the optical axis when the first engaging portion is locked by the locking portion and the first installation portion is installed in the housing. and a third distance between the housing and the optical axis when the second engaging portion is locked by the locking portion and the second installation portion is installed in the housing and the fourth distance are equal to each other. The optical scanning device according to any one of claims 1 to 5,
In the height direction, the optical member is aligned with the housing and the optical axis when the first engaging portion is locked by the locking portion and the first installation portion is installed in the housing. and a third distance between the housing and the optical axis when the second engaging portion is locked by the locking portion and the second installation portion is installed in the housing The optical scanning device, wherein the fourth distance is different. The optical scanning device according to any one of claims 1 to 7,
The optical member includes a lens portion and an outer frame portion provided on the outer circumference of the lens portion,
An optical scanning device, wherein the first engaging portion and the second engaging portion are provided on the outer frame portion. The optical scanning device according to any one of claims 1 to 8,
The optical scanning device , wherein the movement of the optical member in the width direction is restricted by engaging the first engaging portion or the second engaging portion with the engaging portion. The optical scanning device according to any one of claims 1 to 9,
The optical scanning device , wherein the optical member has a rectangular parallelepiped shape in which the length of a side in the optical axis direction is smaller than the length of the other side. The optical scanning device according to any one of claims 1 to 10,
The optical scanning device , wherein the optical member has a lens portion having a spherical surface on an incident side of the light beam and a toroidal surface on the emitting side of the light beam. The optical scanning device according to any one of claims 1 to 11 ,
The support part supports the optical member so as to be arranged at a plurality of different optical axis direction arrangement positions in the optical axis direction and at a plurality of different width direction arrangement positions in the width direction. scanning device. The optical scanning device according to any one of claims 1 to 12 ,
The optical member includes a lens portion and an outer frame portion provided on the outer circumference of the lens portion,
The optical scanning device, wherein the support section has one or more side support sections that support a side surface that intersects the outer peripheral surface of the outer frame section of the optical member. The optical scanning device according to claim 13 ,
The support portion has one side support portion and another side support portion,
one first lens arrangement angle of the optical member supported by the one side support portion and locked by the locking portion; and the locking portion supported by the other side surface support portion An optical scanning device, wherein the angle of arrangement of the second lens of the optical member engaged with the second lens is different from that of the other second lens. The optical scanning device according to any one of claims 1 to 14 ,
An optical scanning device, wherein a plurality of types of beam detectors having different incident positions in an incident direction of the light beam can be attached. The optical scanning device according to any one of claims 1 to 15 ,
2. An optical scanning device according to claim 1 , wherein a plurality of types of deflection scanning members having reflecting surfaces of different sizes in the main scanning direction are replaceable as the deflection scanning member. An image forming apparatus comprising the optical scanning device according to any one of claims 1 to 16 .

Images