JP2008309844A5 - - Google Patents

Claims (7)

複数の光源手段と、前記複数の光源手段から出射された複数の光束を副走査断面内において互いに異なる角度をもって偏向手段の同一の偏向面に導光する入射光学系と、前記偏向手段の同一の偏向面で偏向走査された複数の光束を互いに異なる被走査面上に結像させる２つ以上の結像光学素子を有する結像光学系と、を有する光走査装置において、
前記２つ以上の結像光学素子のうち光路中で前記被走査面に最も近く配置された結像光学素子と前記被走査面との間の光路中には、前記偏向手段の同一の偏向面で偏向走査された光束を反射する反射ミラーが配置されており、
前記結像光学系は、前記偏向面と前記被走査面に最も近く配置された結像光学素子との間の光路中に副走査断面内において負のパワーを有する１つ以上の結像光学素子を有することを特徴とする光走査装置。 A plurality of light source means, an incident optical system for guiding a plurality of light beams emitted from the plurality of light source means to the same deflection surface of the deflection means at different angles in the sub-scan section, and the same of the deflection means In an optical scanning device comprising: an imaging optical system having two or more imaging optical elements that image a plurality of light beams deflected and scanned by a deflection surface on different scanning surfaces;
Of the two or more imaging optical elements, an optical path between the imaging optical element disposed closest to the scanned surface in the optical path and the scanned surface includes the same deflection surface of the deflecting unit. A reflection mirror that reflects the light beam deflected and scanned at is arranged,
The imaging optical system includes one or more imaging optical elements having negative power in a sub-scanning section in an optical path between the deflection surface and the imaging optical element disposed closest to the scanned surface. An optical scanning device comprising: 前記偏向手段の同一の偏向面で偏向走査された複数の光束は、前記結像光学系の同一の結像光学素子を通過することを特徴とする請求項１に記載の光走査装置。 2. The optical scanning device according to claim 1, wherein the plurality of light beams deflected and scanned by the same deflection surface of the deflecting unit pass through the same imaging optical element of the imaging optical system. 前記結像光学系を構成する２つ以上の結像光学素子の中で前記反射ミラーに最も近い位置にある光学面は、副走査断面内において副走査方向にシフト偏心していることを特徴とする請求項１又は２に記載の光走査装置。 Of the two or more imaging optical elements constituting the imaging optical system, an optical surface closest to the reflecting mirror is shifted in the sub-scanning direction in the sub-scanning section. The optical scanning device according to claim 1. 前記被走査面の前記結像光学系の光軸上を走査するときの光束の主光線が、副走査断面内において、前記偏向手段の偏向面にて偏向走査された後に光学基準軸C0と成す角をθs0、前記副走査方向に負のパワーを有する結像光学素子を通過した後に光学基準軸C0と成す角をθs1、光路中で前記被走査面に最も近くに配置された結像光学素子を通過した後に光学基準軸C0と成す角をθs2とするとき、
θs0＜θs1
０(deg)≦θs2
なる条件を満足することを特徴とする請求項２に記載の光走査装置。 The principal ray of the light beam when scanning the scanning surface on the optical axis of the imaging optical system forms the optical reference axis C0 after being deflected and scanned by the deflection surface of the deflection means in the sub-scan section. An imaging optical element having an angle θs0 and an angle formed with the optical reference axis C0 after passing through the imaging optical element having negative power in the sub-scanning direction is θs1, and is disposed closest to the scanned surface in the optical path When the angle formed with the optical reference axis C0 after passing through is θs2,
θs0 <θs1
0 (deg) ≦ θs2
The optical scanning device according to claim 2, wherein the following condition is satisfied. 副走査断面内において、前記偏向手段の偏向面から前記被走査面までの光路長をＬ１、前記偏向面から前記被走査面に最も近い位置にある結像光学素子の光学面までの光路長をＬ２とするとき、
２≦（Ｌ１／Ｌ２）≦４
なる条件を満足することを特徴とする請求項１乃至４の何れか１項に記載の光走査装置。 In the sub-scan section, the optical path length from the deflecting surface of the deflecting means to the scanned surface is L1, and the optical path length from the deflecting surface to the optical surface of the imaging optical element closest to the scanned surface is When L2
2 ≦ (L1 / L2) ≦ 4
5. The optical scanning device according to claim 1, wherein the following condition is satisfied. 前記光源手段の各々は、複数の発光部を有することを特徴とする請求項１乃至５の何れか１項に記載の光走査装置。 6. The optical scanning device according to claim 1, wherein each of the light source means includes a plurality of light emitting units. 請求項１乃至６の何れか１項に記載の光走査装置と、前記被走査面に配置された感光体と、前記光走査装置で走査された光ビームによって前記感光体の上に形成された静電潜像をトナー像として現像する現像器と、現像されたトナー像を被転写材に転写する転写器と、転写されたトナー像を被転写材に定着させる定着器とを有することを特徴とする画像形成装置。 The optical scanning device according to claim 1, a photosensitive member disposed on the surface to be scanned, and a light beam scanned by the optical scanning device, and formed on the photosensitive member. A developing device that develops an electrostatic latent image as a toner image, a transfer device that transfers the developed toner image onto a transfer material, and a fixing device that fixes the transferred toner image onto the transfer material. An image forming apparatus.