Reflection type image forming optical system and projector
Patent 6612704 Issued on September 2, 2003. Estimated Expiration Date: 
December 10, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
December 10, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesScene projector Image projector system Projector Lens-less projection optical system of reflection type Patent #: 6513935 InventorAssigneeApplicationNo. 10/315031 filed on 12/10/2002US Classes:353/99, Plural359/858, Including curved mirror surfaces in series359/859, With concave and convex mirrors in series359/861With three or more successive reflectionsExaminersPrimary: Dowling, William C.Attorney, Agent or FirmInternational ClassH04N 5/74 (20060101)Foreign Application Priority Data2001-12-12 JPAbstractA reflection type image forming optical system and a projector are compact with wide view angle, in expensive and having uniform illumination intensity. The reflection type image forming optical system includes a first reflection mirror having a rotation symmetric aspheric shape concave reflection surface directed to an image forming surface arranged an image forming element thereon, a second reflection mirror having a rotation symmetric aspheric shape convex reflection surface directed toward a flux of light from the first reflection mirror, a third reflection mirror having a rotation symmetric aspheric shape concave reflection surface directed toward a flux of light from the second reflection mirror and a fourth reflection mirror having a rotation symmetric aspheric shape convex reflection surface directed toward a flux of light from the third reflection mirror. The first, second, third and fourth reflection mirrors form a telecentric optical system. | |
