| 摘要 |
A variable focal length mirror assembly incorporates a rigid circular structure (18) defining a hollow chamber (21) with a circular aperture (19). A flexible elastomer (12,13) having a reflective coating (11) is disposed across aperture (19) with coating (11) outwardly facing. The elastomer (12,13) is peripherally gripped and clamped by a circularly-extending clamp means (15,16) located radially outwardly of the structure (18). The clamp means (15,16) are mounted for movement axially of the structure (18) in order to render flat that portion of the elastomer (12,13) covering the aperture (19) in the absence of any applied elastomer deformation force. Means (20) for applying elastomer deformation forces are provided. |
