| 摘要 |
A retractable lens system includes optical elements (L1, 31, L2, L3, F, C) of a photographing optical system, which are positioned on a common optical axis (Z1) when the lens system is in a ready-to-photograph state. The retractable lens system has a front side and a rear side (left and right side respectively in Fig. 3B). When the retractable lens system changes from the ready-to-photograph state to a retracted state, a removable optical element (L2) of the optical elements is moved to a position removed from the common optical axis and moved rearward. One of the optical elements remaining on the common optical axis is also moved rearward. This element includes a linearly movable element (30) which, in the ready-to-photograph state, moves in the common optical axis direction without changing a distance between the linearly movable element and the removable optical element. When the retractable lens system is in the retracted state, the removable optical element and the linearly movable element are intersected by a common plane(S) perpendicular to the common optical axis. Shutter unit (30), low pass filter (F) and CCD image sensor (C) are shown. |
