Patent ID: 8238223

Claim:
A deformable mirror comprising: a reflection mirror having a reflection surface on which light is reflected, at least part of the reflection mirror being made of a ferromagnetic member, the reflection mirror having a deformed state and a non-deformed state; and a switching device that switches the reflection mirror between the deformed state and the non-deformed state using a magnetic force, the switching device having a hard magnetic member made of a hard magnetic material and a magnetizing unit including a magnetizing coil, wherein a current is passed through the switching device by a driving circuit, wherein the magnetizing unit is (i) capable of applying current to the magnetizing coil so that the hard magnetic member enters a state in which the hard magnetic member is magnetized and (ii) capable of applying current to the magnetizing coil so that the hard magnetic member, when in the state in which the hard magnetic member is magnetized, enters a state in which the hard magnetic member is demagnetized, and wherein the current is applied by the driving circuit to the magnetizing coil of the switching device only when the reflection mirror is switched between the deformed state and the non-deformed state.