JP4077138B2

JP4077138B2 - Optical scanning device

Info

Publication number: JP4077138B2
Application number: JP2000180391A
Authority: JP
Inventors: 信昭小野
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 2000-06-15
Filing date: 2000-06-15
Publication date: 2008-04-16
Anticipated expiration: 2020-06-15
Also published as: JP2001356291A

Description

【０００１】
【発明の属する技術分野】
本発明は、デジタル複写機、レーザＦＡＸ、レーザ印刷機またはレーザプロッタ等に使用される光走査装置の発明に関し、特に、複数のユニットを共通とした光走査装置に関する。
【０００２】
【従来の技術】
近年、デジタル複写機、レーザＦＡＸ、レーザ印刷機およびレーザプロッタ等の機器において内部に使われるユニットは可能な限り共通に使用できるように開発が進められている。機器の共通化は、生産性を向上させ低コスト化を実現するだけでなく、廃棄部品を少なくすることができるので地球環境にとって優しいという長所を有するものとなる。
このような機器における光走査装置では、機種毎に走査レンズ系を共通に使用することがしばしば求められるが、機器の価格やスペックによって、走査速度が異なることが通常である。そして、光走査速度が速い高速の光走査装置では、偏向器の回転数を高める必要があり、防音用途の略平行平板の透明部材が通常は不可欠となる。
一方、光走査速度が遅い低速の光走査装置においては、同じ走査レンズを使用しても光走査速度が遅いため偏向器の回転数を低く抑えることができる。このため、低速の光走査装置においては、偏向器の高速回転における風きり音を抑制できるので、防音用としての略平行平板の透明部材が一般に不要になる。しかし、この略平行平板の透明部材は、防音用以外にも防塵用として用いることもできるため、機器によっては採用することもできる。
また、光走査装置として、特開平１１−２１８７１５号公報に記載されたものが知られている。この光走査装置は、光源からの光束を偏向器（回転多面鏡）へ導く際に、途中に配設した２枚のミラーのＺ軸への平行移動により主走査方向の光軸調整を可能にしている。
【０００３】
【発明が解決しようとする課題】
しかしながら、従来の光走査装置においては、複数のユニットを共通とする場合において、防音および防塵用の透明部材を使用するか否かにより光ビームの結像の位置が異なるから、被走査面に光ビームを正確に結像することができないという問題がある。
本発明の課題は、このような問題を解決することにある。すなわち、本発明の目的は、複数のユニットを共通とする場合において、防音および防塵用の透明部材の有無にかかわらず被走査面に光ビームを正確に結像することができる光走査装置を提供することにある。
【０００４】
【課題を解決するための手段】
前記課題を解決するために、請求項１に記載の発明は、光ビームを出射する光源ユニットと、この光源ユニットから出射された光ビームを所定位置に結像する第１結像光学系と、この第１結像光学系からの光ビームを受けて走査する偏向器と、この偏向器からの光ビームを結像して被走査面に照射する第２結像光学系とを有する光走査装置であって、前記光源ユニットと、前記第１結像光学系と、前記偏向器および前記第２結像光学系は箱体に取り付けられ、前記第１結像光学系と前記偏向器との間および前記偏向器と前記第２結像光学系との間に位置するように着脱可能に配置される略平行平板の透明部材を有し、前記第２結像光学系の取り付け位置を前記透明部材の有無に応じて変更可能とすることを特徴とする。
請求項２に記載の発明は、請求項１に記載の光走査装置において、前記第２結像光学系の主走査方向の取り付け位置を前記透明部材の有無に応じて変更可能とすることを特徴とする。
請求項３に記載の発明は、請求項１に記載の光走査装置において、前記第２結像光学系の光軸方向の取り付け位置を前記透明部材の有無に応じて変更可能とすることを特徴とする。
請求項４に記載の発明は、請求項１に記載の光走査装置において、前記第２結像光学系の主走査方向及び光軸方向の取り付け位置を前記透明部材の有無に応じて変更可能とすることを特徴とする。
【０００５】
【発明の実施の形態】
次に、本発明の実施の形態を図を参照しつつ説明する。
図１は、本発明の第１の実施の形態に係る光走査装置を示す略平面図である。図１に示すように、この光走査装置は、光源ユニット１と、第１結像光学系２と、偏向器（ポリゴンミラー）３と、第２結像光学系４と、略平行平板の透明部材５とを有している。
光源ユニット１は、光ビームを出射する。第１結像光学系２は、光源ユニット１から出射された光ビームを所定位置に結像する。偏向器３は、所定方向へ定速で回転され、かつ、第１結像光学系２からのた光ビームを受けて走査する。第２結像光学系４は、偏向器３からの光ビームを結像して被走査面６に照射する。
光源ユニット１は、光ビームを出射する光源１ａと、この光源１ａから出射される光ビームを集光するカップリングレンズ１ｂと、このカップリングレンズ１ｂからの光ビームを絞るアパーチャ１ｃとから構成されている。透明部材５は、第１結像光学系２と偏向器３との間および偏向器３と第２結像光学系４との間に位置するように着脱可能に配置されている。透明部材５は、防音および防塵用のものである。光源ユニット１と、第１結像光学系２と、偏向器３と第２結像光学系４および透明部材５は、箱体７に取り付けられている。
図２は、光走査装置が透明部材５を有する場合と光走査装置が透明部材５を有しない場合における光ビームの経路の差異を示す。図２において、点線は光走査装置が透明部材５を有する場合における光軸を示し、実線は光走査装置が透明部材５を有しない場合における光軸を示す。図２に示すように、光走査装置が透明部材５を有するか否かによって、光軸ずれが生じることが明瞭にわかる。
【０００６】
図３は、光走査装置が透明部材５を有する場合における光像の光軸方向の浮き上がり量（Ｃ１’、Ｃ２’）と、光軸ずれ量（Ｃ１、Ｃ２）とを説明するための図である。図３に示すように、第１結像光学系２からの光ビームの透明部材５における光路長をｂとし、入射角をｕとした場合に、偏向器３における光像の光軸方向の浮上がり量Ｃ１’および光軸ずれ量Ｃ１は、それぞれＣ１’＝ｂｃｏｓｕおよびＣ１＝ｓｉｎｕで表される。また、偏向器３からの光ビームの透明部材５における光路長をｂ’とし、入射角をｕ’とした場合に、被走査面６における光像の光軸方向の浮上がり量Ｃ２’および光軸ずれ量Ｃ２は、それぞれＣ２’＝ｂｃｏｓｕ’およびＣ２＝ｓｉｎｕ’で表される
本発明に係る光走査装置は、このような光軸ずれを防止するものである。次に、本発明の実施の形態を詳細に説明する。
本発明の第１の実施の形態を図１および図４に基づいて説明する。図４は、本発明の第１の実施の形態に係る光走査装置の要部を示す図である。図４に示すように、第２走査結像光学系４は主走査方向（第２結像光学系４の光軸に対して垂直方向）へ位置決めするための突起部８を有している。箱体７には、第２結像光学系４の光軸に対して垂直方向へ所定間隔をおいて２つの受け片９、１０が形成されている。第２走査結像光学系４の突起部８は、２つの受け片９、１０の間に配置されている。
第２走査結像光学系４の突起部８が２つに受け片９、１０のいずれかに当接されることにより第２結像光学系５の主走査方向における位置決めが行われる。すなわち、光走査装置が透明部材５を有しない場合には図２に示すように光軸は実線となるので、図４（２）に示すように第２走査結像光学系４の突起部８が受け片９に当接された状態で位置決めがされる、すなわち、第２走査結像光学系４は図２の実線に示すような位置に位置決めがされる。また、光走査装置が透明部材５を有する場合には図２に示すように光軸は点線となるので、図４（１）に示すように第２走査結像光学系４の突起部８が受け片１０に当接された状態で位置決めがされる、すなわち、第２走査結像光学系４は図２の点線に示すような位置に位置決めがされる。このように、光走査装置における透明部材５の有無によって生じる主走査方向の光軸ずれ量をキャンセル（消去）するように、第２走査結像光学系４の突起部８が２つに受け片９、１０のいずれかに当接されることにより第２走査結像光学系４の位置決めがされる。
【０００７】
次に、本発明の第２の実施の形態を図１および図５に基づいて説明する。図５は、本発明の第２の実施の形態に係る光走査装置の要部を示す図である。本発明の第２の実施の形態においては、本発明の第１の実施の形態と同じ構成要素には同じ参照符号が付されてる。第２走査結像光学系４は、両端部にリブ１１を有している。これらのリブ１１は、第２結像光学系４の光軸方向における位置決めをするためのものである。箱体７には、第２結像光学系４の光軸方向へ所定間隔をおいて２対のリブ受け片１２、１３がそれぞれ形成されている。第２走査結像光学系４のリブ１１は、各対のリブ受け片１２、１３の間にそれぞれ配置されている。
第２走査結像光学系４の各リブ１１がリブ受け片１２、１３のいずれかに当接されることにより第２走査結像光学系４の位置決めがされる。すなわち、光走査装置が透明部材５を有しない場合には図３に示すように光軸は点線となるので、図５（２）に示すように第２走査結像光学系４の各リブ１１がリブ受け片１３に当接された状態で位置決めがされる。また、光走査装置が透明部材５を有する場合には図３に示すように光軸は実線となるので、図５（１）に示すように第２走査結像光学系４の各リブ１１がリブ受け片１２に当接された状態で位置決めがされる。このように、光走査装置における透明部材５の有無によって生じる光像の光軸方向の浮き量をキャンセル（消去）するように、第２走査結像光学系４の各リブ１１がリブ受け片１２、１３のいずれかに当接されることにより第２走査結像光学系４の位置決めがされる。
【０００８】
次に、本発明の第３の実施の形態を図１および図６に基づいて説明する。図６は、本発明の第３の実施の形態に係る光走査装置の要部を示す図である。本発明の第３の実施の形態においては、本発明の第１および第２の実施の形態と同じ構成要素には同じ参照符号が付されてる。
本発明の第３の実施の形態は、本発明の第１実施の形態と第２の実施の形態とを組み合わせたものである。第２走査結像光学系４は主走査方向（第２結像光学系４の光軸に対して垂直方向）へ位置決めするための突起部８を有している。箱体７には、第２結像光学系４の光軸に対して垂直方向へ所定間隔をおいて２つの受け片９、１０が形成されている。第２走査結像光学系４の突起部８は、２つの受け片９、１０の間に配置されている。第２走査結像光学系４の突起部８が２つに受け片９、１０のいずれかに当接されることにより第２結像光学系５の主走査方向における位置決めが行われる。
光走査装置における透明部材５の有無によって生じる光ビームの光軸方向の浮き量をキャンセル（消去）するように、第２走査結像光学系４の突起部８が２つに受け片９、１０のいずれかに当接されることにより第２走査結像光学系４の位置決めがされる。
また、第２走査結像光学系４は、両端部にリブ１１を有している。これらのリブ１１は、第２結像光学系４の光軸方向における位置決めをするためのものである。箱体７には、第２結像光学系４の光軸方向へ所定間隔をおいて２対のリブ受け片１２、１３がそれぞれ形成されている。第２走査結像光学系４のリブ１１は、各対のリブ受け片１２、１３の間にそれぞれ配置されている。
光走査装置における透明部材５の有無によって生じる光像の光軸方向の浮き量をキャンセル（消去）するように、第２走査結像光学系４の各リブ１１がリブ受け片１２、１３のいずれかに当接されることにより第２結像光学系４の光軸方向における位置決めがされる。
【０００９】
【発明の効果】
以上説明したように、請求項１に記載の発明によれば、第１結像光学系と偏向器との間およびこの偏向器と第２結像光学系との間に位置するように着脱可能に配置される略平行平板の透明部材を有し、前記第２結像光学系の取り付け位置を前記透明部材の有無に応じて変更可能とするから、複数のユニットを共通とする場合において、防音および防塵用の透明部材の有無にかかわらず被走査面に光ビームを正確に結像することができる。
請求項２に記載の発明によれば、前記透明部材の有無に応じて、第２結像光学系の取り付け位置を主走査方向に変更できるので、主走査方向の光軸ずれ量を減少させることができる。
請求項３に記載の発明によれば、前記透明部材の有無に応じて、第２結像光学系の取り付け位置を光軸方向に変更できるので、光像の光軸方向の浮き上がり量を減少させることができる。
請求項４に記載の発明によれば、前記透明部材の有無に応じて、第２結像光学系の取り付け位置を主走査方向および光軸方向に変更できるので主走査方向の光軸ずれ量および光像の光軸方向の浮き上がり量の両方を減少させることができる。
また、本発明は、デジタル複写機、レーザＦＡＸ、レーザ印刷機またはレーザプロッタ等の機器に適用可能であり、内部に使われるユニットを共通に使用できるため、生産性を向上させ低コスト化を実現するだけでなく、廃棄部品を少なくすることができるから地球環境にとって優しいという長所を有する。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態に係る光走査装置を示す略平面図である。
【図２】光走査装置が透明部材５を有する場合と光走査装置が透明部材を有しない場合における光ビームの経路の差異を説明するための図である。
【図３】本発明の実施の形態に係る光走査装置が略平行平板の透明部材を有する場合における光像の浮き上がり量（Ｃ１' 、Ｃ２' ）と、光軸ズレ量（Ｃ１、Ｃ２）を説明するための図である。
【図４】（１）および（２）は、本発明の第１の実施の形態に係る光走査装置の要部を示す斜視図である。
【図５】（１）および（２）は、本発明の第２の実施の形態に係る光走査装置の要部を示す斜視図である。
【図６】（１）および（２）は、本発明の第３の実施の形態に係る光走査装置の要部を示す斜視図である。
【符号の説明】
１光源ユニット、２第１結像光学系、３偏向器、４第２結像光学系、５透明部材、６被走査面、７箱体、８突起部、９、１０受け片、１１リブ、１２、１３リブ受け片。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an invention of an optical scanning device used for a digital copying machine, a laser FAX, a laser printer, a laser plotter, or the like, and more particularly to an optical scanning device having a plurality of units in common.
[0002]
[Prior art]
In recent years, development has been progressing so that units used internally in devices such as a digital copying machine, a laser FAX, a laser printer, and a laser plotter can be used in common as much as possible. The standardization of equipment not only improves productivity and lowers costs, but also has the advantage of being friendly to the global environment because it can reduce waste parts.
In an optical scanning apparatus in such an apparatus, it is often required to use a scanning lens system in common for each model, but the scanning speed is usually different depending on the price and specifications of the apparatus. In a high-speed optical scanning device with a high optical scanning speed, it is necessary to increase the number of rotations of the deflector, and a substantially parallel flat transparent member for soundproofing is usually indispensable.
On the other hand, in a low-speed optical scanning device with a low optical scanning speed, the rotational speed of the deflector can be kept low because the optical scanning speed is low even if the same scanning lens is used. For this reason, in a low-speed optical scanning device, wind noise due to high-speed rotation of the deflector can be suppressed, so that a generally parallel flat transparent member for soundproofing is generally unnecessary. However, the substantially parallel flat transparent member can be used not only for soundproofing but also for dustproofing.
Also, an optical scanning device described in Japanese Patent Application Laid-Open No. 11-218715 is known. This optical scanning device makes it possible to adjust the optical axis in the main scanning direction by translating the two mirrors arranged in the middle to the Z-axis when guiding the light beam from the light source to the deflector (rotating polygon mirror). ing.
[0003]
[Problems to be solved by the invention]
However, in the conventional optical scanning device, when a plurality of units are used in common, the light beam imaging position varies depending on whether or not a soundproof and dustproof transparent member is used. There is a problem that the beam cannot be accurately imaged.
An object of the present invention is to solve such a problem. That is, an object of the present invention is to provide an optical scanning device capable of accurately imaging a light beam on a surface to be scanned regardless of the presence or absence of a soundproof and dustproof transparent member when a plurality of units are shared. There is to do.
[0004]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 includes a light source unit that emits a light beam, a first imaging optical system that forms an image of the light beam emitted from the light source unit at a predetermined position, An optical scanning device comprising: a deflector that receives and scans the light beam from the first imaging optical system; and a second imaging optical system that images the light beam from the deflector and irradiates the surface to be scanned. The light source unit, the first imaging optical system, the deflector, and the second imaging optical system are attached to a box, and between the first imaging optical system and the deflector. And a transparent member of a substantially parallel plate that is detachably disposed so as to be located between the deflector and the second imaging optical system, and the mounting position of the second imaging optical system is the transparent member It can be changed according to the presence or absence of.
According to a second aspect of the present invention, in the optical scanning device according to the first aspect, the mounting position of the second imaging optical system in the main scanning direction can be changed according to the presence or absence of the transparent member. And
According to a third aspect of the present invention, in the optical scanning device according to the first aspect, the mounting position of the second imaging optical system in the optical axis direction can be changed according to the presence or absence of the transparent member. And
According to a fourth aspect of the present invention, in the optical scanning device according to the first aspect, the mounting position of the second imaging optical system in the main scanning direction and the optical axis direction can be changed according to the presence or absence of the transparent member. It is characterized by doing.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic plan view showing an optical scanning device according to a first embodiment of the present invention. As shown in FIG. 1, the optical scanning device includes a light source unit 1, a first imaging optical system 2, a deflector (polygon mirror) 3, a second imaging optical system 4, and a transparent substantially parallel plate. Member 5.
The light source unit 1 emits a light beam. The first imaging optical system 2 images the light beam emitted from the light source unit 1 at a predetermined position. The deflector 3 is rotated in a predetermined direction at a constant speed, and receives and scans the light beam from the first imaging optical system 2. The second imaging optical system 4 forms an image of the light beam from the deflector 3 and irradiates the scanned surface 6.
The light source unit 1 includes a light source 1a that emits a light beam, a coupling lens 1b that condenses the light beam emitted from the light source 1a, and an aperture 1c that narrows the light beam from the coupling lens 1b. ing. The transparent member 5 is detachably disposed so as to be positioned between the first imaging optical system 2 and the deflector 3 and between the deflector 3 and the second imaging optical system 4. The transparent member 5 is for soundproofing and dustproofing. The light source unit 1, the first imaging optical system 2, the deflector 3, the second imaging optical system 4, and the transparent member 5 are attached to the box 7.
FIG. 2 shows the difference in the path of the light beam when the optical scanning device has the transparent member 5 and when the optical scanning device does not have the transparent member 5. In FIG. 2, the dotted line indicates the optical axis when the optical scanning device includes the transparent member 5, and the solid line indicates the optical axis when the optical scanning device does not include the transparent member 5. As shown in FIG. 2, it can be clearly seen that the optical axis shift occurs depending on whether or not the optical scanning device has the transparent member 5.
[0006]
FIG. 3 is a diagram for explaining the floating amount (C1 ′, C2 ′) of the optical image in the optical axis direction and the optical axis deviation amount (C1, C2) when the optical scanning device has the transparent member 5. is there. As shown in FIG. 3, when the optical path length of the light beam from the first imaging optical system 2 in the transparent member 5 is b and the incident angle is u, the optical image of the deflector 3 is floated in the optical axis direction. The rising amount C1 ′ and the optical axis deviation amount C1 are expressed by C1 ′ = bcosu and C1 = sinu, respectively. Further, when the optical path length of the light beam from the deflector 3 in the transparent member 5 is b ′ and the incident angle is u ′, the floating amount C2 ′ of the optical image in the optical axis direction on the surface to be scanned 6 and the light The optical scanning device according to the present invention in which the axis deviation amount C2 is expressed by C2 ′ = bcosu ′ and C2 = sinu ′, respectively, prevents such an optical axis deviation. Next, embodiments of the present invention will be described in detail.
A first embodiment of the present invention will be described with reference to FIGS. FIG. 4 is a diagram showing a main part of the optical scanning device according to the first embodiment of the present invention. As shown in FIG. 4, the second scanning imaging optical system 4 has a protrusion 8 for positioning in the main scanning direction (perpendicular to the optical axis of the second imaging optical system 4). In the box 7, two receiving pieces 9, 10 are formed at a predetermined interval in the direction perpendicular to the optical axis of the second imaging optical system 4. The protrusion 8 of the second scanning imaging optical system 4 is disposed between the two receiving pieces 9 and 10.
Positioning of the second imaging optical system 5 in the main scanning direction is performed by bringing the two projections 8 of the second scanning imaging optical system 4 into contact with either one of the receiving pieces 9 and 10. That is, when the optical scanning device does not have the transparent member 5, the optical axis is a solid line as shown in FIG. 2, so that the protrusion 8 of the second scanning imaging optical system 4 is shown in FIG. Is positioned in contact with the receiving piece 9, that is, the second scanning imaging optical system 4 is positioned at the position shown by the solid line in FIG. Further, when the optical scanning device has the transparent member 5, the optical axis is a dotted line as shown in FIG. 2, so that the protrusion 8 of the second scanning imaging optical system 4 is provided as shown in FIG. Positioning is performed with the receiving piece 10 in contact with the receiving piece 10, that is, the second scanning imaging optical system 4 is positioned at a position as shown by a dotted line in FIG. As described above, the two projections 8 of the second scanning imaging optical system 4 receive the two pieces so as to cancel (erase) the amount of optical axis deviation in the main scanning direction caused by the presence or absence of the transparent member 5 in the optical scanning device. The second scanning imaging optical system 4 is positioned by being brought into contact with any one of 9 and 10.
[0007]
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 5 is a diagram showing a main part of an optical scanning device according to the second embodiment of the present invention. In the second embodiment of the present invention, the same components as those in the first embodiment of the present invention are denoted by the same reference numerals. The second scanning imaging optical system 4 has ribs 11 at both ends. These ribs 11 are used for positioning the second imaging optical system 4 in the optical axis direction. In the box 7, two pairs of rib receiving pieces 12 and 13 are formed at predetermined intervals in the optical axis direction of the second imaging optical system 4. The rib 11 of the second scanning imaging optical system 4 is disposed between each pair of rib receiving pieces 12 and 13.
Each rib 11 of the second scanning imaging optical system 4 is brought into contact with one of the rib receiving pieces 12 and 13 so that the second scanning imaging optical system 4 is positioned. That is, when the optical scanning device does not have the transparent member 5, the optical axis is a dotted line as shown in FIG. 3, so that each rib 11 of the second scanning imaging optical system 4 is shown in FIG. Is positioned in contact with the rib receiving piece 13. Further, when the optical scanning device has the transparent member 5, the optical axis is a solid line as shown in FIG. 3, so that each rib 11 of the second scanning imaging optical system 4 is shown in FIG. Positioning is performed with the rib receiving piece 12 in contact with the rib receiving piece 12. In this way, each rib 11 of the second scanning imaging optical system 4 has the rib receiving piece 12 so as to cancel (erase) the floating amount in the optical axis direction of the optical image caused by the presence or absence of the transparent member 5 in the optical scanning device. , 13 is positioned so that the second scanning imaging optical system 4 is positioned.
[0008]
Next, a third embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a diagram showing a main part of an optical scanning device according to the third embodiment of the present invention. In the third embodiment of the present invention, the same components as those in the first and second embodiments of the present invention are denoted by the same reference numerals.
The third embodiment of the present invention is a combination of the first embodiment and the second embodiment of the present invention. The second scanning imaging optical system 4 has a protrusion 8 for positioning in the main scanning direction (perpendicular to the optical axis of the second imaging optical system 4). In the box 7, two receiving pieces 9, 10 are formed at a predetermined interval in the direction perpendicular to the optical axis of the second imaging optical system 4. The protrusion 8 of the second scanning imaging optical system 4 is disposed between the two receiving pieces 9 and 10. Positioning of the second imaging optical system 5 in the main scanning direction is performed by bringing the two projections 8 of the second scanning imaging optical system 4 into contact with either one of the receiving pieces 9 and 10.
Two protrusions 8 of the second scanning imaging optical system 4 receive the pieces 9, 10 so as to cancel (erase) the amount of floating of the light beam in the optical axis direction caused by the presence or absence of the transparent member 5 in the optical scanning device. The second scanning imaging optical system 4 is positioned by being brought into contact with any one of the above.
The second scanning imaging optical system 4 has ribs 11 at both ends. These ribs 11 are used for positioning the second imaging optical system 4 in the optical axis direction. In the box 7, two pairs of rib receiving pieces 12 and 13 are formed at predetermined intervals in the optical axis direction of the second imaging optical system 4. The rib 11 of the second scanning imaging optical system 4 is disposed between each pair of rib receiving pieces 12 and 13.
Each rib 11 of the second scanning imaging optical system 4 has any of the rib receiving pieces 12 and 13 so as to cancel (erase) the floating amount in the optical axis direction of the optical image caused by the presence or absence of the transparent member 5 in the optical scanning device. The second imaging optical system 4 is positioned in the optical axis direction by being in contact with each other.
[0009]
【The invention's effect】
As described above, according to the first aspect of the present invention, it is detachable so as to be positioned between the first imaging optical system and the deflector and between the deflector and the second imaging optical system. In the case where a plurality of units are used in common, it is possible to change the mounting position of the second imaging optical system according to the presence or absence of the transparent member. In addition, a light beam can be accurately imaged on the surface to be scanned regardless of the presence or absence of a dustproof transparent member.
According to the second aspect of the present invention, since the mounting position of the second imaging optical system can be changed in the main scanning direction according to the presence or absence of the transparent member, the amount of optical axis deviation in the main scanning direction can be reduced. Can do.
According to the third aspect of the present invention, since the mounting position of the second imaging optical system can be changed in the optical axis direction according to the presence or absence of the transparent member, the floating amount of the optical image in the optical axis direction is reduced. be able to.
According to the fourth aspect of the present invention, since the mounting position of the second imaging optical system can be changed in the main scanning direction and the optical axis direction depending on the presence or absence of the transparent member, the amount of optical axis deviation in the main scanning direction and Both the floating amount of the optical image in the optical axis direction can be reduced.
In addition, the present invention can be applied to devices such as a digital copying machine, a laser FAX, a laser printer, or a laser plotter, and since the unit used inside can be used in common, the productivity is improved and the cost is reduced. In addition, it has the advantage of being friendly to the global environment because it can reduce the number of waste parts.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing an optical scanning device according to a first embodiment of the present invention.
FIG. 2 is a diagram for explaining a difference in a light beam path when the optical scanning device has a transparent member 5 and when the optical scanning device does not have a transparent member.
FIG. 3 shows the amount of floating of an optical image (C1 ′, C2 ′) and the amount of optical axis misalignment (C1, C2) when the optical scanning device according to the embodiment of the present invention has a transparent member having a substantially parallel plate. It is a figure for demonstrating.
FIGS. 4A and 4B are perspective views illustrating a main part of the optical scanning device according to the first embodiment of the present invention. FIGS.
FIGS. 5A and 5B are perspective views showing a main part of an optical scanning device according to a second embodiment of the present invention. FIGS.
FIGS. 6A and 6B are perspective views illustrating a main part of an optical scanning device according to a third embodiment of the present invention. FIGS.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Light source unit, 2 1st imaging optical system, 3 Deflector, 4 2nd imaging optical system, 5 Transparent member, 6 Surface to be scanned, 7 Box body, 8 Projection part, 9, 10 Receiving piece, 11 rib, 12, 13 Rib receiving piece.

Claims

A light source unit that emits a light beam, a first imaging optical system that forms an image of the light beam emitted from the light source unit at a predetermined position, and a deflection that receives and scans the light beam from the first imaging optical system And a second imaging optical system that forms an image of the light beam from the deflector and irradiates the surface to be scanned with the light source unit, the first imaging optical system, The deflector and the second imaging optical system are attached to a box, and are positioned between the first imaging optical system and the deflector and between the deflector and the second imaging optical system. An optical scanning device having a substantially parallel plate-shaped transparent member which is detachably arranged so that the mounting position of the second imaging optical system can be changed according to the presence or absence of the transparent member. .

2. The optical scanning device according to claim 1, wherein an attachment position of the second imaging optical system in the main scanning direction can be changed according to the presence or absence of the transparent member.

2. The optical scanning device according to claim 1, wherein the mounting position of the second imaging optical system in the optical axis direction can be changed according to the presence or absence of the transparent member.

2. The optical scanning device according to claim 1, wherein the mounting positions of the second imaging optical system in the main scanning direction and the optical axis direction can be changed according to the presence or absence of the transparent member. .