| 摘要 |
<p>PURPOSE: To simplify constitution in the mirror body of an optical equipment having a zooming optical system, and to surely attain shading regardless of a zooming operation. CONSTITUTION: A first lens group is fixed in a moving mirror body 22, and a second lens group 40 is arranged so as to be operated relatively to the first lens. A third lens group 44 is positioned at the back part of the second lens group 40. A shading member 24 is housed between a first holder 26 which supports the first lens group and a second holder 28 which supports the second lens group 40. The shading member 24 is constituted by winding a strip piece made of a metallic board like a spiral, and this is provided with an elastic force in an axial direction. When the first lens group and the second lens group 40 are relatively moved according to zooming, the shading member 24 executes shading when part of each roll part expands and contracts in an overlapped state. At the same time, the shading member 24 is functioned as an elastic member for energizing the both lens groups in the axial direction, and a distance between the lens groups is maintained to be a prescribed value.</p> |
