JP3773641B2

JP3773641B2 - Multi-beam light source device

Info

Publication number: JP3773641B2
Application number: JP34898297A
Authority: JP
Inventors: 智宏中島
Original assignee: Ricoh Co Ltd
Current assignee: Ricoh Co Ltd
Priority date: 1997-12-18
Filing date: 1997-12-18
Publication date: 2006-05-10
Anticipated expiration: 2017-12-18
Also published as: JPH11183813A

Description

【０００１】
【発明の属する技術分野】
本発明はデジタル複写機、レーザプリンタ等の書込系に用いられる光走査装置のマルチビーム光源装置に関する。
【０００２】
【従来の技術】
デジタル複写機、レーザプリンタ等の書込系に用いられる光走査装置においては、記録速度を向上させる手段は、光ビームを偏向走査する走査手段としてのポリゴンミラーの回転速度を上げる方式がある。しかし、この方式では、ポリゴンミラーを回転させるモータの耐久性や騒音、振動、光ビームの変調速度等が問題となり、限界がある。
【０００３】
そこで、光走査装置において、一度に複数の光ビームを走査して複数ラインを同時に記録するマルチビーム走査装置が提案されている。このマルチビーム走査装置としては、複数の半導体レーザからの光ビームをビームスプリッタを用いて合成する方式や、特開昭５６ー４２２４８号公報に記載されているように複数の発光源がアレイ状に配列された半導体レーザアレイを用いる方式、複数個の汎用の半導体レーザを用いる方式がある。この複数個の汎用の半導体レーザを用いる方式は、特開平７ー７２４０７号公報に記載されているように２個の半導体レーザからの光ビームをビーム合成手段を用いて合成して一度に隣接した２ラインを走査する方式が公知である。
【０００４】
【発明が解決しようとする課題】
上記半導体レーザアレイは、制御面での制約があり、汎用の半導体レーザと同様に扱うことができず、高精度な出力制御に不向きである上に、光源が複数であるにも拘らずコリメートレンズが共通であるために光源間の波長の差や発光点位置の差が残って結像位置がずれたり、コリメートレンズから射出される光ビームが各々離反する方向へ発散してしまったりする等取扱が厄介である。
【０００５】
一方、汎用の半導体レーザを２つ以上用いて複数の光ビームをビームスプリッタやプリズムにより合成する場合には、上記特開平７ー７２４０７号公報に記載されている方式では、複数の半導体レーザからの光ビームを１つのビームスプリッタで合成することにより構成が簡単で、かつ、経時的なずれが少なく、安定性に優れたマルチビーム光源装置を実現することができる。
【０００６】
このマルチビーム光源装置においては、主走査方向に各半導体レーザからの光ビーム射出方向を隔てることで、装置全体を走査光学系が収容される光学ハウジングに取り付ける際に光軸を回転中心とした調整を行うことにより、副走査方向の光ビームスポット間隔を設定していた。
【０００７】
しかしながら、このマルチビーム光源装置から射出される光ビームの形状は楕円であるため、各半導体レーザからの光ビーム射出方向を決定するコリメートレンズとの調整において設定値が大きくずれていると、装置全体を回転する量も大きくなり、光ビーム自体が傾いて所定の光ビームスポット径が得られないという不具合が生ずる。
【０００８】
本発明は、光ビームスポット径のばらつきを抑えて高品位な画像記録を行うことができ、組立て作業を簡易化することができて生産効率を向上させることができるマルチビーム光源装置を提供することを目的とする。
【０００９】
【課題を解決するための手段】
上記目的を達成するため、請求項１に係る発明は、複数の半導体レーザと、この複数の半導体レーザと対で設けられ該複数の半導体レーザからの光ビームを概略平行光束にする複数のコリメータレンズと、この複数のコリメータレンズ及び前記複数の半導体レーザを光ビーム射出方向を合わせて一体的に支持する支持部材と、前記複数のコリメータレンズからの光ビームを副走査方向に近接させて射出する光学素子を含むビーム合成手段とを有するマルチビーム光源装置において、前記ビーム合成手段と前記支持部材とは所定の光軸に垂直な面で接合するとともに、同面内での相対角度を可変としたものである。
【００１０】
請求項２に係る発明は、２個の半導体レーザと、この２個の半導体レーザと対で設けられ該２個の半導体レーザからの光ビームを概略平行光束にする２個のコリメータレンズと、この２個のコリメータレンズ及び前記２個の半導体レーザを光ビーム射出方向を合わせて一体的に支持する支持部材と、前記２個のコリメータレンズからの光ビームを副走査方向に近接させて射出する光学素子を含むビーム合成手段とを有し、このビーム合成手段と前記支持部材とは所定の光軸に垂直な面で接合するとともに、同面内での相対角度を可変としたマルチビーム光源装置において、各光ビームの前記ビーム合成手段射出方向の副走査方向成分が所定量となるように前記ビーム合成手段と前記支持部材との相対角度を設定したものである。
【００１１】
請求項３に係る発明は、主走査方向に隣接して配置された２個の半導体レーザ及び他の１個の半導体レーザと、この３個の半導体レーザと対で設けられ該３個の半導体レーザからの光ビームを概略平行光束にする３個のコリメータレンズと、この３個のコリメータレンズ及び前記３個の半導体レーザを光ビーム射出方向を合わせて一体的に支持する支持部材と、前記３個のコリメータレンズからの光ビームのうち前記２個の半導体レーザからの交差する方向に傾いた２つの光ビームと前記１個の半導体レーザからの１つの光ビームを副走査方向に近接させて射出するビーム合成手段とを有し、このビーム合成手段と前記支持部材とは所定の光軸に垂直な面で接合するとともに、同面内での相対角度を可変としたマルチビーム光源装置において、前記１つの光ビームの射出方向をなす第１の射出軸と、前記２つの光ビームの射出方向の対称軸をなす第２の射出軸との副走査方向成分が所定量となるように前記ビーム合成手段と前記支持部材との相対角度を設定したものである。
【００１２】
請求項４に係る発明は、請求項１記載のマルチビーム光源装置において、前記ビーム合成手段は前記支持部材との相対角度を光軸を回転中心として調整可能に形成されたビーム合成手段支持手段に収納されてなるとともに、前記回転中心を基準として走査光学系ハウジングに対する位置決めを行ったものである。
【００１３】
請求項５に係る発明は、請求項３記載のマルチビーム光源装置において、前記第１の射出軸と前記第２の射出軸とを光軸に対して対称になるように設定したものである。
請求項６に係る発明は、複数の半導体レーザと、前記複数の半導体レーザと対で設けられ前記複数の半導体レーザからの光ビームを概略平行光束にする複数のコリメータレンズと、前記複数のコリメータレンズ及び前記複数の半導体レーザを光ビーム射出方向を合わせて一体的に支持する支持部材と、前記複数のコリメータレンズからの光ビームを副走査方向に近接させて射出する光学素子を含むビーム合成手段とを有するマルチビーム光源装置において、前記複数の半導体レーザと前記複数のコリメータレンズを各々偏心させ、前記ビーム合成手段と前記支持部材とは所定の光軸に垂直な面で接合するとともに、同面内での相対角度を可変としたものである。
請求項７に係る発明は、複数の半導体レーザと、前記複数の半導体レーザと対で設けられ前記複数の半導体レーザからの光ビームを概略平行光束にする複数のコリメータレンズと、前記複数のコリメータレンズ及び前記複数の半導体レーザを光ビーム射出方向を合わせて一体的に支持する支持部材と、前記複数のコリメータレンズからの光ビームを副走査方向に近接させて射出する光学素子を含むビーム合成手段とを有し、光学系ハウジングに位置決めされるマルチビーム光源装置において、前記ビーム合成手段と前記支持部材とは所定の光軸に垂直な面で接合するとともに、同面内での相対角度を可変とする第一の調整手段と、前記光軸を中心に前記光学系ハウジングに回動可能に位置決めする第二の調整手段とを有するものである。
請求項８に係る発明は、請求項７記載のマルチビーム光源装置において、前記光学系ハウジングは、円筒部により回転可能に支持されるものである。
【００１４】
【発明の実施の形態】
図２は本発明を応用した光走査装置の第１実施形態を示す。この第１実施形態は、マルチビーム光源装置として汎用の半導体レーザを例えば２個用いた２ビーム光源ユニットを搭載した光走査装置の一実施形態であり、デジタル複写機、レーザプリンタ等の書込系に用いられる。この光走査装置においては、２ビーム光源ユニット１０１より射出された２つの光ビームは、シリンダレンズ１０２を介して走査手段としてのポリゴンミラー１０３の反射位置近傍で交叉した後、ポリゴンミラー１０３で偏向走査される。
【００１５】
このポリゴンミラー１０３で偏向走査された光ビームは、２枚構成のｆθレンズ１０４を通過して折返しミラー１０５で感光体からなる像担持体、例えば感光体ドラム１０７に向けて反射され、トロイダルレンズ１０６により感光体ドラム１０７に結像される。感光体ドラム１０７は、駆動部により回転駆動されて副走査方向に移動し、帯電手段により一様に帯電された後にトロイダルレンズ１０６からの２つの光ビームにより主走査方向（Ｙ方向）に走査されることで、副走査方向に所定のピッチで隣接した２ラインの画像記録が同時に行われる。
【００１６】
また、同期検知用ミラー１０８は画像領域外に配置されており、折返しミラー１０５からの光ビームが同期検知用ミラー１０８により反射されて同期検知センサ１０９により検出されることで、各光ビームの主走査方向Ｓの走査開始位置が検出される。ここに、同期検知センサ１０９は折返しミラー１０５から時系列に入射する２つの光ビームを検出し、この同期検知センサ１０９からの検出信号により感光体ドラム１０７の画像書き込みタイミングが揃えられる。
【００１７】
すなわち、同期検知センサ１０９の各光ビームに対する検出信号にそれぞれ同期して２ビーム光源ユニット１０１内の各半導体レーザ２０１、２０２が変調部で画像信号により変調されて２ビーム光源ユニット１０１から画像信号により変調された２つの光ビームが射出され、感光体ドラム１０７がトロイダルレンズ１０６からの２つの光ビームにより画像が書き込まれて静電潜像が形成される。この感光体ドラム１０７上の静電潜像は現像装置により現像されて転写手段により紙などに転写される。
【００１８】
図１は上記マルチビーム光源装置としての２ビーム光源ユニット１０１の構成を示す。この２ビーム光源ユニット１０１においては、汎用の半導体レーザ２０１、２０２は、アルミダイキャスト製の支持部材２０３の裏側に、副走査方向（Ｚ方向）に所定の間隔を隔てて並列に形成された図示しない嵌合穴に各々圧入されて支持される。
【００１９】
また、コリメータレンズ２０４、２０５は、Ｙ方向（主走査方向）及びＺ方向に垂直なＸ方向について半導体レーザ２０１、２０２の発散光束が平行光束となるように位置を合わせるとともに、Ｙ方向及びＺ方向について光ビーム射出方向が所定の方向となるように位置を合わせて、半導体レーザ２０１、２０２と対になるように支持部材２０３に形成されたＵ字状の支持部２０３ー１、２０３ー２との隙間にＵＶ硬化接着剤が充填されてＵ字状の支持部２０３ー１、２０３ー２に固定される。ここで、半導体レーザ２０１、２０２とコリメータレンズ２０４、２０５とは若干偏心させることで、光軸Ｃに対して対称に主走査方向の角度を隔てて各光ビームの射出軸が設定される。
【００２０】
半導体レーザ２０１からの光ビームの第１の射出軸に半導体レーザ２０２からの光ビームの第２の射出軸を近接させて光ビームを合成するビーム合成手段としてのプリズム２０６は、支持部材２０７にその裏側より位置決め収容される。支持部材２０７の裏側には支持部材２０３の円筒部２０３ー３の外周が嵌合する嵌合穴が形成され、この嵌合穴に支持部材２０３の円筒部２０３ー３の外周が嵌合嵌合されて支持部材２０７の光軸Ｃに垂直な面が支持部材２０３に当接されることでプリズム２０６と支持部材２０３とが光軸Ｃに垂直な面で接合され、ネジ２０８、２０９により支持部材２０３、２０７が一体に取り付けられる。
【００２１】
この場合、上記第１の射出軸と上記第２の射出軸とは光軸Ｃに対して対称に設定される。支持部材２０３の円筒部２０３ー３の中心位置は光軸Ｃに一致しており、これを回転中心として支持部材２０３を支持部材２０７に対して相対的に回転させる調整により、プリズム２０６で合成された各光ビームの相対角度の副走査方向成分（各光ビームのプリズム２０６射出方向の副走査方向成分）が所定量になるように、例えばゼロに近づくように支持部材２０３の位置を光軸Ｃを中心としてθ方向について決定してネジ２０８、２０９で支持部材２０３を支持部材２０７に止めることで、被走査面としての感光体ドラム１０７の表面上で各光ビームスポットが副走査方向に一致して光軸Ｃを挟んで主走査方向に並列となる状態となす。
【００２２】
なお、この調整を行うため、支持部材２０７のネジ２０８、２０９が通される貫通穴２０７ー１、２０７ー２は光軸Ｃを中心とした長穴をなしている。この２ビーム光源ユニット１０１は、プリズム２０６を支持する支持部材２０７に形成されている走査光学系ハウジングへの位置決め穴に係合する光軸Ｃを中心とした円筒部２０７ー３により回転可能に支持され、その回転αにより副走査方向の光ビームピッチが記録ピッチに一致するように調整される。
【００２３】
ビーム合成手段としてのプリズム２０６は、平行四辺形柱と三角柱とを用いたもので、一方の光源としての半導体レーザ２０１からの光ビームがそのまま透過する。もう一方の光源としての半導体レーザ２０２からの光ビームはプリズム２０６の平行四辺形柱の片側斜面２０６ー１で上方に反射され、プリズム２０６のビームスプリッタを構成する三角柱が平行四辺形柱に接合される斜面２０６ー２にて各光ビームの間隔が光軸に近接されて射出される。
【００２４】
なお、光軸Ｃとは、走査光学系を構成するレンズ群の中心軸を通る通路とする。このように、半導体レーザ２０１、２０２からの光ビームは、コリメータレンズ２０４、２０５により平行光束となり、プリズム２０６により合成されて支持部材２０７の円筒部２０７ー３から射出される。
【００２５】
この第１実施形態は、請求項１に係る発明を応用した光走査装置の一実施形態であって、複数の半導体レーザ２０１、２０２と、この複数の半導体レーザ２０１、２０２と対で設けられ該複数の半導体レーザ２０１、２０２からの光ビームを概略平行光束にする複数のコリメータレンズ２０４、２０５と、この複数のコリメータレンズ２０４、２０５及び前記複数の半導体レーザ２０１、２０２を光ビーム射出方向を合わせて一体的に支持する支持部材２０３と、前記複数のコリメータレンズ２０４、２０５からの光ビームを副走査方向に近接させて射出するビーム合成手段としてのプリズム２０６とを有するマルチビーム光源装置において、前記ビーム合成手段２０６と前記支持部材２０３とは所定の光軸に垂直な面で接合するとともに、同面内での相対角度を可変としたので、各光ビームの光源装置からの射出方向を調節することができ、被走査面としての感光体ドラム上の各光ビームスポットの副走査方向の間隔を記録ピッチに合わせることができる。
【００２６】
また、この第１実施形態は、請求項２に係る発明を応用した光走査装置の一実施形態であって、２個の半導体レーザ２０１、２０２と、この２個の半導体レーザ２０１、２０２と対で設けられ該２個の半導体レーザ２０１、２０２からの光ビームを概略平行光束にする２個のコリメータレンズ２０４、２０５と、この２個のコリメータレンズ２０４、２０５及び前記２個の半導体レーザ２０１、２０２を光ビーム射出方向を合わせて一体的に支持する支持部材２０３と、前記２個のコリメータレンズ２０４、２０５からの光ビームを副走査方向に近接させて射出するビーム合成手段としてのプリズム２０６とを有し、このビーム合成手段２０６と前記支持部材２０３とは所定の光軸に垂直な面で接合するとともに、同面内での相対角度を可変としたマルチビーム光源装置において、各光ビームの前記ビーム合成手段２０６射出方向の副走査方向成分が所定量となるように前記ビーム合成手段２０６と前記支持部材２０３との相対角度を設定したので、各光ビームの光源装置から射出される副走査方向の相対角度を所定範囲内に抑えることができ、光源装置全体の回転による調整量を軽減することができ、光源装置から射出される光ビームの傾きを最小限に抑えることができる。従って、光ビームスポット径のばらつきを抑えて高品位な画像記録を行うことができる。
【００２７】
また、この第１実施形態は、請求項４に係る発明を応用した光走査装置の一実施形態であって、請求項１記載のマルチビーム光源装置において、前記ビーム合成手段２０６は前記支持部材２０３との相対角度を光軸を回転中心として調整可能に形成されたビーム合成手段支持手段としての支持部材２０７に収納されてなるとともに、前記回転中心を基準として走査光学系ハウジングに対する位置決めを行ったので、プリズム２０６の半導体レーザ２０１、２０２支持部材２０３に対する相対角度の調整がラフであっても光源装置全体の回転による副走査方向光ビーム間隔の調整にてプリズム２０６の半導体レーザ２０１、２０２支持部材２０３に対する相対角度の微調整を行うことができ、作業効率を向上させることができる。また、プリズム２０６を半導体レーザ２０１、２０２支持部材２０３の接着等で直接保持するのに比べて、組み付け時にミスが生じてもプリズムを破損させることがない。
【００２８】
図３及び図４は本発明を応用した光走査装置の第２実施形態を示す。この第２実施形態は、マルチビーム光源装置として汎用の半導体レーザを３個用いた３ビーム光源ユニットを搭載した光走査装置の一実施形態であり、上記第１実施形態において、上記２ビーム光源ユニット１０１の代りに用いられる。汎用の半導体レーザ３０１、３０２、３０３は、アルミダイキャスト製の支持部材３０４の裏側に形成された図示しない嵌合穴に各々圧入されて支持される。
【００２９】
コリメータレンズ３０５、３０６、３０７は、Ｙ方向（主走査方向）及びＺ方向に垂直なＸ方向について半導体レーザ３０１、３０２、３０３の発散光束が平行光束となるように位置を合わせるとともに、Ｙ方向及びＺ方向について光ビーム射出方向が所定の方向となるように位置を合わせて、支持部材３０４に形成されたＵ字状支持部３０４ー１、３０４ー２との隙間に充填されたＵＶ硬化接着剤によりＵ字状支持部３０４ー１、３０４ー２に固定される。
【００３０】
支持部材３０３は、半導体レーザ３０２、３０３、コリメータレンズ３０６、３０７がそれぞれ光軸Ｃに対して主走査方向（Ｙ方向）に対称に隣接して配置され、かつ、汎用の半導体レーザ３０１とコリメータレンズ３０５とが副走査方向（Ｚ方向）に所定の間隔を隔てて並列に配置されるように形成される。
【００３１】
ここで、半導体レーザ３０２の光ビーム射出方向と半導体レーザ３０３の光ビーム射出方向は、半導体レーザ３０２、３０３の間隔に対してコリメータレンズ３０６、３０７の間隔を小さく設定する、つまり、半導体レーザ３０２、３０３に対してコリメータレンズ３０６、３０７を偏心させて配置することで、半導体レーザ３０２、３０３からの各光ビームが第２の射出軸ａに対して対称に各々交差するように所定の角度を有する。この実施形態では、この半導体レーザ３０２、３０３からの各光ビームが交差する位置はポリゴンミラー１０３の反射面近傍となるように半導体レーザ３０２、３０３の光ビーム射出方向が設定される。
【００３２】
半導体レーザ３０１の光ビーム射出方向は、プリズム３０８にて半導体レーザ３０１〜３０３からの光ビームが合成されて半導体レーザ３０１の光ビーム射出軸としての第１の射出軸ｂが第２の射出軸ａと光軸Ｃに対して対称になるように設定される。ビーム合成手段としてのプリズム３０８は、支持部材３０９にその裏側より位置決め収容される。
【００３３】
支持部材３０９の裏側には支持部材３０４の円筒部３０４ー３の外周が嵌合する嵌合穴が形成され、この嵌合穴に支持部材３０４の円筒部３０４ー３の外周が嵌合されて支持部材３０９の光軸Ｃに垂直な面が支持部材３０４に当接されることでプリズム３０８と支持部材３０４とが光軸Ｃに垂直な面で接合され、ネジ３１０、３１１により支持部材３０４、３０９が一体に取り付けられる。
【００３４】
支持部材３０４の円筒部３０４ー３の中心位置は光軸Ｃに一致しており、これを回転中心として支持部材３０４を支持部材３０９に対して相対的に回転させる調整により、第１の射出軸ｂと第２の射出軸ａとの相対角度の副走査方向成分が所定量になるように、例えばゼロに近づくように支持部材３０４の位置を光軸Ｃを中心としてθ方向について決定してネジ３１０、３１１で支持部材３０４を支持部材３０９に止める。
【００３５】
この時、図５に示すように被走査面としての感光体ドラム１０７の表面上での第１の射出軸ｂと第２の射出軸ａとの到達点は副走査方向に一致して主走査方向に並列となる状態となり、これにより、半導体レーザ３０２、３０３からの光ビームによる光ビームスポットＬＤ２−Ｌ、ＬＤ２−Ｒの結線上に半導体レーザ３０１からの光ビームによる光ビームスポットＬＤ１が移動してほぼ一直線上に光ビームスポットＬＤ１、ＬＤ２−Ｌ、ＬＤ２−Ｒが配列される。
【００３６】
なお、この調整を行うため、支持部材３０９のネジ３１０、３１１が通される貫通穴３０９ー１、３０９ー２は光軸Ｃを中心とした長穴をなしている。この３ビーム光源ユニットは、プリズム３０８を支持する支持部材３０９に形成されている走査光学系ハウジングへの位置決め穴に係合する光軸Ｃを中心とした円筒部３０９ー３により回転可能に支持され、その回転αにより副走査方向の光ビームピッチが記録ピッチに一致するように調整される。
【００３７】
ビーム合成手段としてのプリズム３０８は、平行四辺形柱と三角柱とを用いたもので、半導体レーザ３０１からの光ビームがそのまま透過する。半導体レーザ３０２、３０３からの光ビームはプリズム３０８の平行四辺形柱の片側斜面３０８ー１で上方に反射され、プリズム３０８のビームスプリッタを構成する三角柱が平行四辺形柱に接合される斜面３０８ー２にて各光ビームの間隔が光軸に近接されて射出される。
【００３８】
このように、半導体レーザ３０１〜３０３からの光ビームは、コリメータレンズ３０５〜３０７により平行光束となり、プリズム３０８により合成されて支持部材３０９の円筒部３０９ー３から射出される。
【００３９】
この第２実施形態は、請求項３に係る発明を応用した光走査装置の一実施形態であって、主走査方向に隣接して配置された２個の半導体レーザ３０２、３０３及び他の１個の半導体レーザ３０１と、この３個の半導体レーザ３０１〜３０３と対で設けられ該３個の半導体レーザ３０１〜３０３からの光ビームを概略平行光束にする３個のコリメータレンズ３０５〜３０７と、この３個のコリメータレンズ３０５〜３０７及び前記３個の半導体レーザ３０１〜３０３を光ビーム射出方向を合わせて一体的に支持する支持部材３０４と、前記３個のコリメータレンズ３０５〜３０７からの光ビームのうち前記２個の半導体レーザ３０２、３０３からの交差する方向に傾いた２つの光ビームと前記１個の半導体レーザ３０１からの１つの光ビームを副走査方向に近接させて射出するビーム合成手段としてのプリズム３０８とを有し、このビーム合成手段３０８と前記支持部材３０４とは所定の光軸Ｃに垂直な面で接合するとともに、同面内での相対角度を可変としたマルチビーム光源装置において、前記１つの光ビームの射出方向をなす第１の射出軸ｂと、前記２つの光ビームの射出方向の対称軸をなす第２の射出軸ａとの副走査方向成分が所定量となるように前記ビーム合成手段３０８と前記支持部材３０４との相対角度を設定したので、各光ビームの光源装置から射出される副走査方向の相対角度を所定範囲内に抑えることができ、光源装置全体の回転による調整量を軽減することができ、光源装置から射出された光ビームの傾きを最小限に抑えることができる。従って、光ビームスポット径のばらつきを抑えて高品位な画像記録を行うことができる。
【００４０】
また、この第２実施形態は、請求項５に係る発明を応用した光走査装置の一実施形態であって、請求項３記載のマルチビーム光源装置において、前記第１の射出軸ｂと前記第２の射出軸ａとを光軸に対して対称になるように設定したので、各射出軸の副走査方向の相対角度を合わせることができ、各光ビームスポットを一直線上に配列することができる。従って、光源装置全体の回転により容易に副走査方向の光ビーム間隔を調整することができ、組立て作業を簡易化して組立効率を向上させることができ、生産効率を向上させることができる。
【００４１】
なお、本発明は上記実施形態に限定されるものではなく、例えば上記実施形態ではプリズムは支持部材に収納する構成としたが、本発明は、この限りではなく、半導体レーザの支持部材にプリズムを接着等で直接に支持させても構わない。
【００４２】
【発明の効果】
以上のように請求項１に係る発明によれば、上記構成により、各光ビームの光源装置からの射出方向を調節することができ、被走査面上の各光ビームスポットの副走査方向の間隔を記録ピッチに合わせることができる。
【００４３】
請求項２に係る発明によれば、上記構成により、各光ビームの光源装置から射出される副走査方向の相対角度を所定範囲内に抑えることができ、光源装置全体の回転による調整量を軽減することができ、光源装置から射出される光ビームの傾きを最小限に抑えることができる。従って、光ビームスポット径のばらつきを抑えて高品位な画像記録を行うことができる。
【００４４】
請求項３に係る発明によれば、上記構成により、各光ビームの光源装置から射出される副走査方向の相対角度を所定範囲内に抑えることができ、光源装置全体の回転による調整量を軽減することができ、光源装置から射出された光ビームの傾きを最小限に抑えることができる。従って、光ビームスポット径のばらつきを抑えて高品位な画像記録を行うことができる。
【００４５】
請求項４に係る発明によれば、上記構成により、ビーム合成手段の半導体レーザ支持手段に対する相対角度の調整がラフであっても光源装置全体の回転による副走査方向光ビーム間隔の調整にてビーム合成手段の半導体レーザ支持手段に対する相対角度の微調整を行うことができ、作業効率を向上させることができる。また、ビーム合成手段を半導体支持手段の接着等で直接保持するのに比べて、組み付け時にミスが生じてもビーム合成手段を破損させることがない。
【００４６】
請求項５に係る発明によれば、上記構成により、各射出軸の副走査方向の相対角度を合わせることができ、各光ビームスポットを一直線上に配列することができる。従って、光源装置全体の回転により容易に副走査方向の光ビーム間隔を調整することができ、組立て作業を簡易化して組立効率を向上させることができ、生産効率を向上させることができる。
請求項６に係る発明によれば、上記構成により、各光ビームの光源装置からの射出方向を調節することができ、被走査面上の各光ビームスポットの副走査方向の間隔を記録ピッチに合わせることができる。
請求項７、８に係る発明によれば、上記構成により、各光ビームの光源装置からの射出方向を２段階の調整で調節することができ、被走査面上の各光ビームスポットの副走査方向の間隔を記録ピッチに合わせることができる。
【図面の簡単な説明】
【図１】本発明を応用した光走査装置の第１実施形態における２ビーム光源ユニットを分解して示す概略図である。
【図２】同第１実施形態を示す斜視図である。
【図３】本発明を応用した光走査装置の第２実施形態における３ビーム光源ユニットを示す断面図である。
【図４】同３ビーム光源ユニットを分解して示す概略図である。
【図５】同３ビーム光源ユニットを説明するための図である。
【符号の説明】
２０１、２０２、３０１〜３０３半導体レーザ
２０３、２０７、３０４、３０９支持部材
２０４、２０５、３０５〜３０７コリメータレンズ
２０６、３０８プリズム[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-beam light source device for an optical scanning device used in a writing system such as a digital copying machine and a laser printer.
[0002]
[Prior art]
In an optical scanning apparatus used in a writing system such as a digital copying machine or a laser printer, there is a method for increasing the rotational speed of a polygon mirror as a scanning means for deflecting and scanning a light beam as a means for improving the recording speed. However, this method has its limitations due to problems such as durability, noise, vibration, and light beam modulation speed of the motor that rotates the polygon mirror.
[0003]
Therefore, a multi-beam scanning device that scans a plurality of light beams at a time and records a plurality of lines simultaneously has been proposed. As this multi-beam scanning device, a method of combining light beams from a plurality of semiconductor lasers using a beam splitter, or a plurality of light emitting sources arranged in an array as described in Japanese Patent Laid-Open No. 56-42248. There are a method using an arrayed semiconductor laser array and a method using a plurality of general-purpose semiconductor lasers. This method using a plurality of general-purpose semiconductor lasers is composed of light beams from two semiconductor lasers combined using beam combining means as described in JP-A-7-72407 and adjacent to each other at once. A method of scanning two lines is known.
[0004]
[Problems to be solved by the invention]
The above-mentioned semiconductor laser array is limited in terms of control, cannot be handled in the same way as a general-purpose semiconductor laser, is not suitable for high-precision output control, and is a collimating lens despite having a plurality of light sources. The difference in wavelength between the light sources and the difference in the light emitting point position remains, and the imaging position shifts, and the light beams emitted from the collimating lens diverge in the directions away from each other. Is troublesome.
[0005]
On the other hand, when two or more general-purpose semiconductor lasers are used to synthesize a plurality of light beams with a beam splitter or prism, the method described in the above-mentioned Japanese Patent Application Laid-Open No. 7-72407 uses a plurality of semiconductor lasers. By combining the light beams with a single beam splitter, a multi-beam light source device having a simple configuration and little deviation with time and excellent stability can be realized.
[0006]
In this multi-beam light source device, by adjusting the light beam emission direction from each semiconductor laser in the main scanning direction, adjustment is made with the optical axis as the rotation center when the entire device is attached to the optical housing that houses the scanning optical system. Thus, the light beam spot interval in the sub-scanning direction is set.
[0007]
However, since the shape of the light beam emitted from the multi-beam light source device is an ellipse, if the setting value is greatly shifted in the adjustment with the collimating lens that determines the light beam emission direction from each semiconductor laser, the entire device As the amount of rotation of the light beam increases, the light beam itself tilts and a predetermined light beam spot diameter cannot be obtained.
[0008]
The present invention provides a multi-beam light source device capable of performing high-quality image recording while suppressing variations in the light beam spot diameter, simplifying assembly work, and improving production efficiency. With the goal.
[0009]
[Means for Solving the Problems]
  In order to achieve the above object, an invention according to claim 1 includes a plurality of semiconductor lasers and a plurality of collimator lenses which are provided in pairs with the plurality of semiconductor lasers and make light beams from the plurality of semiconductor lasers approximately parallel light beams. And a support member that integrally supports the plurality of collimator lenses and the plurality of semiconductor lasers in the light beam emission direction, and the light beams from the plurality of collimator lenses are emitted close to each other in the sub-scanning direction.Includes optical elementsIn the multi-beam light source device having beam combining means, the beam combining means and the support member are joined on a plane perpendicular to a predetermined optical axis, and the relative angle in the same plane is variable.
[0010]
  According to a second aspect of the present invention, there are provided two semiconductor lasers, two collimator lenses provided in pairs with the two semiconductor lasers, and making the light beams from the two semiconductor lasers substantially parallel luminous fluxes, A support member that integrally supports the two collimator lenses and the two semiconductor lasers in the light beam emission direction, and the light beams from the two collimator lenses are emitted close to each other in the sub-scanning direction.Includes optical elementsIn a multi-beam light source device having a beam synthesizing unit, the beam synthesizing unit and the support member being joined on a plane perpendicular to a predetermined optical axis and having a variable relative angle in the same plane, The relative angle between the beam synthesizing unit and the support member is set so that the sub-scanning direction component of the beam in the beam synthesizing unit emission direction becomes a predetermined amount.
[0011]
According to a third aspect of the present invention, two semiconductor lasers and one other semiconductor laser arranged adjacent to each other in the main scanning direction, and the three semiconductor lasers provided in pairs with the three semiconductor lasers. Three collimating lenses that make the light beam from the light beam substantially parallel, a supporting member that integrally supports the three collimating lenses and the three semiconductor lasers in the light beam emitting direction, and the three Among the light beams from the collimator lens, two light beams inclined in the intersecting direction from the two semiconductor lasers and one light beam from the one semiconductor laser are emitted close to each other in the sub-scanning direction. A multi-beam light source device having a beam synthesizing unit, the beam synthesizing unit and the support member being joined by a plane perpendicular to a predetermined optical axis and having a variable relative angle in the same plane. The beam is set so that a sub-scanning direction component between a first emission axis forming the emission direction of the one light beam and a second emission axis forming a symmetry axis of the emission direction of the two light beams becomes a predetermined amount. The relative angle between the synthesizing means and the support member is set.
[0012]
According to a fourth aspect of the present invention, in the multi-beam light source device according to the first aspect, the beam synthesizing unit is a beam synthesizing unit supporting unit formed so that a relative angle with the support member can be adjusted with the optical axis as a rotation center. It is housed and positioned with respect to the scanning optical system housing with the rotation center as a reference.
[0013]
  The invention according to claim 5 is the multi-beam light source device according to claim 3, wherein the first emission axis and the second emission axis are set to be symmetric with respect to the optical axis.
  According to a sixth aspect of the present invention, there are provided a plurality of semiconductor lasers, a plurality of collimator lenses provided in pairs with the plurality of semiconductor lasers to make light beams from the plurality of semiconductor lasers substantially parallel light beams, and the plurality of collimator lenses. And a beam synthesizing unit including a support member that integrally supports the plurality of semiconductor lasers in the light beam emission direction, and an optical element that emits the light beams from the plurality of collimator lenses in the vicinity of the sub-scanning direction; The plurality of semiconductor lasers and the plurality of collimator lenses are each decentered, and the beam synthesizing unit and the support member are joined to each other on a plane perpendicular to a predetermined optical axis. The relative angle at is variable.
  The invention according to claim 7 includes a plurality of semiconductor lasers, a plurality of collimator lenses which are provided in pairs with the plurality of semiconductor lasers and which make light beams from the plurality of semiconductor lasers substantially parallel light beams, and the plurality of collimator lenses. And a beam synthesizing unit including a support member that integrally supports the plurality of semiconductor lasers in the light beam emission direction, and an optical element that emits the light beams from the plurality of collimator lenses in the vicinity of the sub-scanning direction; In the multi-beam light source device positioned in the optical system housing, the beam synthesizing means and the support member are joined on a plane perpendicular to a predetermined optical axis, and a relative angle in the same plane is variable. And a second adjusting means for pivotally positioning the optical system housing about the optical axis.
  The invention according to claim 8 is the multi-beam light source device according to claim 7, wherein the optical system housing is rotatably supported by a cylindrical portion.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 2 shows a first embodiment of an optical scanning apparatus to which the present invention is applied. The first embodiment is an embodiment of an optical scanning device equipped with a two-beam light source unit using, for example, two general-purpose semiconductor lasers as a multi-beam light source device, and a writing system such as a digital copying machine or a laser printer. Used for. In this optical scanning device, the two light beams emitted from the two-beam light source unit 101 intersect with each other in the vicinity of the reflection position of the polygon mirror 103 as scanning means via the cylinder lens 102, and then deflect and scan with the polygon mirror 103. Is done.
[0015]
The light beam deflected and scanned by the polygon mirror 103 passes through the two-piece fθ lens 104 and is reflected by the folding mirror 105 toward the image carrier made of a photosensitive member, for example, the photosensitive drum 107, and the toroidal lens 106. As a result, an image is formed on the photosensitive drum 107. The photosensitive drum 107 is rotationally driven by the driving unit and moves in the sub-scanning direction. After being uniformly charged by the charging unit, the photosensitive drum 107 is scanned in the main scanning direction (Y direction) by the two light beams from the toroidal lens 106. As a result, image recording of two lines adjacent at a predetermined pitch in the sub-scanning direction is simultaneously performed.
[0016]
Further, the synchronization detection mirror 108 is disposed outside the image area, and the light beam from the folding mirror 105 is reflected by the synchronization detection mirror 108 and detected by the synchronization detection sensor 109, so that the main beam of each light beam is detected. A scanning start position in the scanning direction S is detected. Here, the synchronization detection sensor 109 detects two light beams incident in time series from the folding mirror 105, and the image writing timing of the photosensitive drum 107 is aligned by the detection signal from the synchronization detection sensor 109.
[0017]
In other words, the semiconductor lasers 201 and 202 in the two-beam light source unit 101 are modulated by the image signal by the modulation unit in synchronization with the detection signals for the respective light beams of the synchronization detection sensor 109, and the image signal from the two-beam light source unit 101 is received by the image signal. Two modulated light beams are emitted, and the photosensitive drum 107 is written with the two light beams from the toroidal lens 106 to form an electrostatic latent image. The electrostatic latent image on the photosensitive drum 107 is developed by a developing device and transferred to paper or the like by a transfer unit.
[0018]
FIG. 1 shows a configuration of a two-beam light source unit 101 as the multi-beam light source device. In this two-beam light source unit 101, general-purpose semiconductor lasers 201 and 202 are formed in parallel on the back side of a support member 203 made of aluminum die-cast at a predetermined interval in the sub-scanning direction (Z direction). It is press-fitted and supported in the fitting holes that are not.
[0019]
The collimator lenses 204 and 205 are aligned so that the divergent light beams of the semiconductor lasers 201 and 202 become parallel light beams in the Y direction (main scanning direction) and the X direction perpendicular to the Z direction, and the Y direction and the Z direction. The U-shaped support portions 203-1 and 203-2 formed on the support member 203 so as to be paired with the semiconductor lasers 201 and 202 are aligned so that the light beam emission direction is a predetermined direction. The gap is filled with UV curable adhesive and fixed to the U-shaped support portions 203-1 and 203-2. Here, the semiconductor lasers 201 and 202 and the collimator lenses 204 and 205 are slightly decentered to set the emission axis of each light beam symmetrically with respect to the optical axis C with an angle in the main scanning direction.
[0020]
A prism 206 serving as a beam combining means for combining the light beam from the semiconductor laser 201 with the first light output axis of the light beam from the semiconductor laser 202 to synthesize the light beam is provided on the support member 207. Positioned and accommodated from the back side. A fitting hole in which the outer periphery of the cylindrical portion 203-3 of the supporting member 203 is fitted is formed on the back side of the supporting member 207, and the outer periphery of the cylindrical portion 203-3 of the supporting member 203 is fitted and fitted into this fitting hole. Then, the surface perpendicular to the optical axis C of the support member 207 is brought into contact with the support member 203, whereby the prism 206 and the support member 203 are joined to each other at the surface perpendicular to the optical axis C, and the support member is fixed by screws 208 and 209. 203 and 207 are integrally attached.
[0021]
In this case, the first emission axis and the second emission axis are set symmetrically with respect to the optical axis C. The center position of the cylindrical portion 203-3 of the support member 203 coincides with the optical axis C, and is synthesized by the prism 206 by adjusting the rotation of the support member 203 relative to the support member 207 with this as the center of rotation. Further, the position of the support member 203 is moved to the optical axis C so as to approach zero, for example, so that the sub-scanning direction component of the relative angle of each light beam (sub-scanning direction component in the emission direction of the prism 206 of each light beam) becomes a predetermined amount. And the support member 203 is fixed to the support member 207 with screws 208 and 209, so that each light beam spot coincides with the sub-scanning direction on the surface of the photosensitive drum 107 as a surface to be scanned. Thus, the optical axis C is arranged in parallel in the main scanning direction.
[0022]
In order to perform this adjustment, the through holes 207-1 and 207-2 through which the screws 208 and 209 of the support member 207 are passed are long holes with the optical axis C as the center. The two-beam light source unit 101 is rotatably supported by a cylindrical portion 207-3 centered on an optical axis C that engages with a positioning hole for a scanning optical system housing formed on a support member 207 that supports a prism 206. Then, the rotation α adjusts the light beam pitch in the sub-scanning direction to coincide with the recording pitch.
[0023]
The prism 206 as beam combining means uses a parallelogram prism and a triangular prism, and the light beam from the semiconductor laser 201 as one light source is transmitted as it is. The light beam from the semiconductor laser 202 as the other light source is reflected upward by the one-side slope 206-1 of the parallelogram column of the prism 206, and the triangular column constituting the beam splitter of the prism 206 is joined to the parallelogram column. On the inclined surface 206-2, the intervals between the light beams are emitted close to the optical axis.
[0024]
The optical axis C is a path that passes through the central axis of the lens group constituting the scanning optical system. As described above, the light beams from the semiconductor lasers 201 and 202 are converted into parallel light beams by the collimator lenses 204 and 205, synthesized by the prism 206, and emitted from the cylindrical portion 207-3 of the support member 207.
[0025]
The first embodiment is an embodiment of an optical scanning device to which the invention according to claim 1 is applied, and is provided in pairs with a plurality of semiconductor lasers 201 and 202 and the plurality of semiconductor lasers 201 and 202. A plurality of collimator lenses 204 and 205 for converting light beams from a plurality of semiconductor lasers 201 and 202 into a substantially parallel light beam, and a plurality of collimator lenses 204 and 205 and the plurality of semiconductor lasers 201 and 202 are aligned in the light beam emission direction. A multi-beam light source device including a support member 203 that integrally supports the light beam from the plurality of collimator lenses 204 and 205, and a prism 206 as a beam combining unit that emits light beams close to each other in the sub-scanning direction. The beam combining means 206 and the support member 203 are joined on a plane perpendicular to a predetermined optical axis, Since the relative angle in the plane is variable, the emission direction of each light beam from the light source device can be adjusted, and the interval in the sub-scanning direction of each light beam spot on the photosensitive drum as the scanned surface can be adjusted. Can be adjusted to the recording pitch.
[0026]
The first embodiment is an embodiment of an optical scanning apparatus to which the invention according to claim 2 is applied, and is composed of two semiconductor lasers 201 and 202 and two semiconductor lasers 201 and 202. And two collimator lenses 204 and 205 which make the light beams from the two semiconductor lasers 201 and 202 substantially parallel light beams, and the two collimator lenses 204 and 205 and the two semiconductor lasers 201, A support member 203 that integrally supports 202 in the light beam emission direction, and a prism 206 as a beam combining unit that emits light beams from the two collimator lenses 204 and 205 in the sub-scanning direction. The beam combining means 206 and the support member 203 are joined on a plane perpendicular to a predetermined optical axis, and the relative angle in the same plane is variable. In the multi-beam light source device, since the relative angle between the beam synthesizing unit 206 and the support member 203 is set so that the sub-scanning direction component of each light beam in the emission direction of the beam synthesizing unit 206 becomes a predetermined amount, The relative angle of the light beam emitted from the light source device in the sub-scanning direction can be suppressed within a predetermined range, the adjustment amount due to the rotation of the entire light source device can be reduced, and the inclination of the light beam emitted from the light source device Can be minimized. Accordingly, high-quality image recording can be performed while suppressing variations in the light beam spot diameter.
[0027]
The first embodiment is an embodiment of an optical scanning device to which the invention according to claim 4 is applied. In the multi-beam light source device according to claim 1, the beam combining means 206 is the support member 203. Is stored in a support member 207 as a beam combining means support means formed so that the relative angle can be adjusted with the optical axis as the rotation center, and positioning with respect to the scanning optical system housing is performed with reference to the rotation center. Even if the relative angle of the prism 206 with respect to the semiconductor laser 201, 202 support member 203 is rough, the semiconductor laser 201, 202 support member 203 of the prism 206 is adjusted by adjusting the light beam interval in the sub-scanning direction by the rotation of the entire light source device. The relative angle with respect to can be finely adjusted, and the working efficiency can be improved. Further, as compared with the case where the prism 206 is directly held by bonding the semiconductor lasers 201 and 202 with the support member 203, the prism is not damaged even if a mistake occurs during assembly.
[0028]
3 and 4 show a second embodiment of an optical scanning device to which the present invention is applied. The second embodiment is an embodiment of an optical scanning device equipped with a three-beam light source unit using three general-purpose semiconductor lasers as a multi-beam light source device. In the first embodiment, the two-beam light source unit is Used in place of 101. General-purpose semiconductor lasers 301, 302, and 303 are supported by being press-fitted into fitting holes (not shown) formed on the back side of a support member 304 made of aluminum die cast.
[0029]
The collimator lenses 305, 306, and 307 are aligned so that the divergent light beams of the semiconductor lasers 301, 302, and 303 become parallel light beams in the Y direction (main scanning direction) and the X direction perpendicular to the Z direction. The UV curable adhesive filled in the gap between the U-shaped support portions 304-1 and 304-2 formed on the support member 304 by aligning the positions so that the light beam emission direction is a predetermined direction in the Z direction. By this, it is fixed to the U-shaped support portions 304-1, 304-2.
[0030]
The support member 303 includes semiconductor lasers 302 and 303 and collimator lenses 306 and 307 arranged symmetrically adjacent to the optical axis C in the main scanning direction (Y direction), and a general-purpose semiconductor laser 301 and a collimator lens. 305 are arranged in parallel in the sub-scanning direction (Z direction) at a predetermined interval.
[0031]
Here, the light beam emission direction of the semiconductor laser 302 and the light beam emission direction of the semiconductor laser 303 set the interval between the collimator lenses 306 and 307 smaller than the interval between the semiconductor lasers 302 and 303, that is, the semiconductor laser 302, By disposing the collimator lenses 306 and 307 eccentrically with respect to 303, each light beam from the semiconductor lasers 302 and 303 has a predetermined angle so as to cross each other symmetrically with respect to the second emission axis a. . In this embodiment, the light beam emission directions of the semiconductor lasers 302 and 303 are set so that the positions at which the light beams from the semiconductor lasers 302 and 303 intersect are in the vicinity of the reflection surface of the polygon mirror 103.
[0032]
The light beam emission direction of the semiconductor laser 301 is such that the light beam from the semiconductor lasers 301 to 303 is synthesized by the prism 308 and the first emission axis b as the light beam emission axis of the semiconductor laser 301 is the second emission axis a. And symmetric with respect to the optical axis C. The prism 308 as beam combining means is positioned and accommodated on the support member 309 from the back side.
[0033]
A fitting hole in which the outer periphery of the cylindrical portion 304-3 of the supporting member 304 is fitted is formed on the back side of the supporting member 309, and the outer periphery of the cylindrical portion 304-3 of the supporting member 304 is fitted into this fitting hole. The surface perpendicular to the optical axis C of the support member 309 is brought into contact with the support member 304, so that the prism 308 and the support member 304 are joined to each other at the surface perpendicular to the optical axis C, and the support member 304, 309 is attached integrally.
[0034]
The center position of the cylindrical portion 304-3 of the support member 304 coincides with the optical axis C, and the first injection axis is adjusted by adjusting the support member 304 relative to the support member 309 with this as the center of rotation. The position of the support member 304 is determined in the θ direction about the optical axis C so that the sub-scanning direction component of the relative angle between b and the second emission axis a becomes a predetermined amount, for example, so as to approach zero. At 310 and 311, the support member 304 is stopped on the support member 309.
[0035]
At this time, as shown in FIG. 5, the arrival point of the first emission axis b and the second emission axis a on the surface of the photosensitive drum 107 as the surface to be scanned coincides with the sub-scanning direction and performs the main scanning. As a result, the light beam spot LD1 due to the light beam from the semiconductor laser 301 moves on the connection of the light beam spots LD2-L and LD2-R due to the light beams from the semiconductor lasers 302 and 303. Thus, the light beam spots LD1, LD2-L, and LD2-R are arranged substantially on a straight line.
[0036]
In order to perform this adjustment, the through holes 309-1 and 309-2 through which the screws 310 and 311 of the support member 309 are passed have long holes with the optical axis C as the center. This three-beam light source unit is rotatably supported by a cylindrical portion 309-3 centered on the optical axis C that engages with a positioning hole for a scanning optical system housing formed in a support member 309 that supports a prism 308. The rotation α adjusts the light beam pitch in the sub-scanning direction to coincide with the recording pitch.
[0037]
The prism 308 as a beam combining unit uses a parallelogram column and a triangular column, and the light beam from the semiconductor laser 301 is transmitted as it is. The light beams from the semiconductor lasers 302 and 303 are reflected upward by the one-side slope 308-1 of the parallelogram prism of the prism 308, and the slope 308- where the triangular prism constituting the beam splitter of the prism 308 is joined to the parallelogram pillar. 2, the intervals between the light beams are emitted close to the optical axis.
[0038]
As described above, the light beams from the semiconductor lasers 301 to 303 are converted into parallel light beams by the collimator lenses 305 to 307, synthesized by the prism 308, and emitted from the cylindrical portion 309-3 of the support member 309.
[0039]
The second embodiment is an embodiment of an optical scanning device to which the invention according to claim 3 is applied, and two semiconductor lasers 302 and 303 and another one arranged adjacent to each other in the main scanning direction. The three semiconductor lasers 301 to 303 and three collimator lenses 305 to 307 provided in pairs with the three semiconductor lasers 301 to 303 to convert the light beams from the three semiconductor lasers 301 to 303 into substantially parallel beams, A support member 304 that integrally supports the three collimator lenses 305 to 307 and the three semiconductor lasers 301 to 303 in accordance with the light beam emission direction, and the light beams from the three collimator lenses 305 to 307. Of these, two light beams inclined in the intersecting direction from the two semiconductor lasers 302 and 303 and one light beam from the one semiconductor laser 301 are combined. A prism 308 serving as a beam combining unit that emits light in the vicinity of the scanning direction. The beam combining unit 308 and the support member 304 are joined to each other on a plane perpendicular to a predetermined optical axis C, and within the same plane. In the multi-beam light source device in which the relative angle is variable, the first emission axis b that forms the emission direction of the one light beam and the second emission axis a that forms the symmetry axis of the emission direction of the two light beams. Since the relative angle between the beam combining means 308 and the support member 304 is set so that the sub-scanning direction component becomes a predetermined amount, the relative angle in the sub-scanning direction of each light beam emitted from the light source device is predetermined. Thus, the amount of adjustment due to the rotation of the entire light source device can be reduced, and the inclination of the light beam emitted from the light source device can be minimized. Accordingly, high-quality image recording can be performed while suppressing variations in the light beam spot diameter.
[0040]
The second embodiment is an embodiment of an optical scanning device to which the invention according to claim 5 is applied. In the multi-beam light source device according to claim 3, the first emission axis b and the first Since the two exit axes a are set to be symmetric with respect to the optical axis, the relative angles of the exit axes in the sub-scanning direction can be matched, and the light beam spots can be arranged on a straight line. . Accordingly, the light beam interval in the sub-scanning direction can be easily adjusted by rotating the entire light source device, the assembling work can be simplified and the assembling efficiency can be improved, and the production efficiency can be improved.
[0041]
The present invention is not limited to the above embodiment. For example, in the above embodiment, the prism is housed in the support member. However, the present invention is not limited to this, and the prism is mounted on the support member of the semiconductor laser. It may be supported directly by bonding or the like.
[0042]
【The invention's effect】
As described above, according to the first aspect of the present invention, with the above-described configuration, the emission direction of each light beam from the light source device can be adjusted, and the interval between the light beam spots on the scanned surface in the sub-scanning direction. Can be adjusted to the recording pitch.
[0043]
According to the second aspect of the present invention, with the above configuration, the relative angle of each light beam emitted from the light source device in the sub-scanning direction can be suppressed within a predetermined range, and the adjustment amount due to the rotation of the entire light source device is reduced. The inclination of the light beam emitted from the light source device can be minimized. Therefore, high-quality image recording can be performed while suppressing variations in the light beam spot diameter.
[0044]
According to the third aspect of the invention, with the above configuration, the relative angle of each light beam emitted from the light source device in the sub-scanning direction can be suppressed within a predetermined range, and the adjustment amount due to the rotation of the entire light source device is reduced. The inclination of the light beam emitted from the light source device can be minimized. Accordingly, high-quality image recording can be performed while suppressing variations in the light beam spot diameter.
[0045]
According to the invention of claim 4, with the above configuration, even if the adjustment of the relative angle of the beam combining means to the semiconductor laser support means is rough, the beam can be adjusted by adjusting the light beam interval in the sub-scanning direction by the rotation of the entire light source device. Fine adjustment of the relative angle of the synthesizing unit to the semiconductor laser supporting unit can be performed, and the working efficiency can be improved. Further, as compared with the case where the beam combining means is directly held by bonding the semiconductor support means or the like, the beam combining means is not damaged even if an error occurs during assembly.
[0046]
  According to the fifth aspect of the present invention, with the above configuration, the relative angles of the respective emission axes in the sub-scanning direction can be matched, and the respective light beam spots can be arranged on a straight line. Accordingly, the light beam interval in the sub-scanning direction can be easily adjusted by rotating the entire light source device, the assembling work can be simplified and the assembling efficiency can be improved, and the production efficiency can be improved.
  According to the invention of claim 6, with the above-described configuration, the emission direction of each light beam from the light source device can be adjusted, and the interval in the sub-scanning direction of each light beam spot on the surface to be scanned is set to the recording pitch. Can be matched.
  According to the seventh and eighth aspects of the invention, with the above-described configuration, the emission direction of each light beam from the light source device can be adjusted in two steps, and the sub-scanning of each light beam spot on the surface to be scanned is performed. The direction interval can be adjusted to the recording pitch.
[Brief description of the drawings]
FIG. 1 is an exploded schematic view showing a two-beam light source unit in a first embodiment of an optical scanning device to which the present invention is applied.
FIG. 2 is a perspective view showing the first embodiment.
FIG. 3 is a cross-sectional view showing a three-beam light source unit in a second embodiment of an optical scanning device to which the present invention is applied.
FIG. 4 is an exploded schematic view showing the three-beam light source unit.
FIG. 5 is a diagram for explaining the same three-beam light source unit.
[Explanation of symbols]
201, 202, 301-303 Semiconductor laser
203, 207, 304, 309 Support member
204, 205, 305-307 Collimator lens
206, 308 Prism

Claims

A plurality of semiconductor lasers;
A plurality of collimator lenses which are provided in pairs with the plurality of semiconductor lasers and make the light beams from the plurality of semiconductor lasers substantially parallel beams;
A support member that integrally supports the plurality of collimator lenses and the plurality of semiconductor lasers in accordance with the light beam emission direction;
A multi-beam light source device including a beam combining unit including an optical element that emits light beams from the plurality of collimator lenses close to each other in a sub-scanning direction;
The beam combining means and the support member are joined on a plane perpendicular to a predetermined optical axis, and the relative angle in the same plane is variable.

Two semiconductor lasers;
Two collimator lenses which are provided in pairs with the two semiconductor lasers and make the light beams from the two semiconductor lasers approximately parallel beams;
A support member that integrally supports the two collimator lenses and the two semiconductor lasers in accordance with the light beam emission direction;
Beam combining means including an optical element that emits light beams from the two collimator lenses close to each other in the sub-scanning direction;
In the multi-beam light source device in which the beam combining means and the support member are joined on a plane perpendicular to a predetermined optical axis, and the relative angle in the same plane is variable,
A multi-beam light source device characterized in that a relative angle between the beam synthesizing unit and the support member is set so that a sub-scanning direction component of each light beam in an emission direction of the beam synthesizing unit becomes a predetermined amount.

Two semiconductor lasers arranged adjacent to each other in the main scanning direction and one other semiconductor laser and a pair of these three semiconductor lasers are provided as a pair of light beams from the three semiconductor lasers. Three collimating lenses, a supporting member that integrally supports the three collimating lenses and the three semiconductor lasers in the light beam emitting direction, and the light beams from the three collimating lenses. Among them, there are two light beams inclined in the intersecting direction from the two semiconductor lasers, and a beam combining means for emitting one light beam from the one semiconductor laser close to the sub-scanning direction, and In the multi-beam light source device in which the beam combining means and the support member are joined on a plane perpendicular to a predetermined optical axis and the relative angle in the same plane is variable, The beam synthesizing means and the support member so that a sub-scanning direction component between the first emission axis forming the emission direction and the second emission axis forming the symmetry axis of the emission direction of the two light beams becomes a predetermined amount. A multi-beam light source device characterized in that a relative angle with respect to is set.

2. The multi-beam light source device according to claim 1, wherein the beam synthesizing means is housed in a beam synthesizing means support means formed so that a relative angle with the support member can be adjusted with an optical axis as a rotation center, and the rotation. A multi-beam light source device characterized by positioning relative to a scanning optical system housing with a center as a reference.

4. The multi-beam light source device according to claim 3, wherein the first emission axis and the second emission axis are set to be symmetrical with respect to the optical axis.

A plurality of semiconductor lasers;
A plurality of collimator lenses which are provided in pairs with the plurality of semiconductor lasers and which make light beams from the plurality of semiconductor lasers substantially parallel beams;
The light beam emitting direction of the plurality of collimator lenses and the plurality of semiconductor lasers are aligned. A support member that supports the
A multi-beam light source device including a beam combining unit including an optical element that emits light beams from the plurality of collimator lenses close to each other in a sub-scanning direction;
Decentering each of the plurality of semiconductor lasers and the plurality of collimator lenses,
The beam combining means and the support member are joined on a plane perpendicular to a predetermined optical axis, and the relative angle in the same plane is variable.

A plurality of semiconductor lasers;
A plurality of collimator lenses which are provided in pairs with the plurality of semiconductor lasers and which make light beams from the plurality of semiconductor lasers substantially parallel beams;
A support member that integrally supports the plurality of collimator lenses and the plurality of semiconductor lasers in accordance with a light beam emission direction;
A beam combining means including an optical element that emits light beams from the plurality of collimator lenses close to each other in a sub-scanning direction, and a multi-beam light source device positioned in an optical system housing,
The beam combining means and the support member are joined by a plane perpendicular to a predetermined optical axis, and a first adjustment means for making the relative angle variable within the same plane;
A multi-beam light source device, comprising: a second adjusting unit that is pivotably positioned in the optical system housing about the optical axis.

8. The multi-beam light source device according to claim 7, wherein the optical system housing is rotatably supported by a cylindrical portion.