Patent ID: 7777976
Filing Date: 2010-08-17
Classification: G02B

Abstract:
1. An imaging device comprising: an image sensor with a rectangular imaging surface having two short sides and two long sides; an imaging optical system which forms an image on said image sensor, said imaging optical system including an on-axis lens element which is always positioned on an imaging optical axis and a radially-retractable lens element movable between an on-axis position in which said radially-retractable lens element is positioned on said imaging optical axis and an off-axis displaced position in which said radially-retractable lens element is displaced from said imaging optical axis; and a swingable arm which is pivoted about a swing axis which is eccentrically positioned with respect to said imaging optical axis, said radially-retractable lens element being supported by a free end of said swingable arm, wherein said on-axis lens element has a non-circular outer shape defined by at least one removed portion which is removed from a reference circle having a center on said imaging optical axis along at least one of said two long sides of said rectangular imaging surface, wherein, when said radially-retractable lens element is in said off-axis displaced position, said radially-retractable lens element is positioned at said removed portion of said on-axis lens element and an optical axis of said radially-retractable lens element is offset from an on-axis plane which passes through said imaging optical axis of said on-axis lens element and which is parallel to said two short sides of said rectangular imaging surface, and wherein said swing axis is positioned adjacent to one of said two short sides of said rectangular imaging surface that is closer to said optical axis of said radially-retractable lens element in said off-axis displaced position.