| 摘要 |
A flexible membrane mirror comprises a housing (10) containing a closed space (19) delimited in part by a tensioned reflective flexible membrane (M) and means (14, 14a, 32, 31, 30, 18b) to vary the pressure in the closed space (19) to alter the radius of curvature of the membrane (M) and thus to vary the power of the mirror. The means to vary the pressure in the space (19) delimited by the reflective membrane (M) includes clutch means (29, 31) in the pressure varying means. |
