Abstract: An optical system having a deformable mirror is such that, in order to minimize variation of an image position on an imaging plane, or of a ray position, in at least two states where shapes of the deformable mirror are different, first- and lower-order terms of an equation expressing a surface of the deformable mirror are changed in the two states. As a result, an optical system including variable optical-property elements such as a variable focal-length lens, a deformable mirror, and a variable prism, and an optical apparatus having the optical system can be provided which is small in power consumption, noiseless, short in response time, simple in mechanical structure, and low in cost, minimize variation of the image position on the imaging plane, and permits sufficient correction for aberration caused by a shape error or the like.

Abstract: An optical system having a deformable mirror is such that, in order to minimize variation of an image position on an imaging plane, or of a ray position, in at least two states where shapes of the deformable mirror are different, first- and lower-order terms of an equation expressing a surface of the deformable mirror are changed in the two states. As a result, an optical system including variable optical-property elements such as a variable focal-length lens, a deformable mirror, and a variable prism, and an optical apparatus having the optical system can be provided which is small in power consumption, noiseless, short in response time, simple in mechanical structure, and low in cost, minimize variation of the image position on the imaging plane, and permits sufficient correction for aberration caused by a shape error or the like.