The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 12, 1999
Filed:
Apr. 10, 1996
Junichi Oka, Hikone, JP;
Dainippon Screen, Mfg. Co., Ltd., Osaka, JP;
Abstract
The light emitted from a point light source is converged by a relay lens to form an intermediate image which is an enlarged image of the light source. The light source and the relay lens are accommodated in the same lens-barrel, and are thereby united as a light source unit. When a problem occurs in the light source, the light source is not independently replaced, but the light source unit is replaced as a unit. That is to say, the intermediate image formed by the light source unit is used as an apparent new light source (referred to as a 'pseudo light source'). The emitted luminous flux from this pseudo light source is made parallel by a collimator lens and then is linearly focused into an image on a reflection plane of a deflector by a first cylindrical lens. First cylindrical lens 6 has its focal point in a plane including the rotation axis of the deflector and a slit. The light deflected by the deflector is focused into an image with a prescribed beam diameter on a photosensitive material by a second image forming optical system formed of an f.theta. lens and a curved second cylindrical lens.