Patent attributes
Support device for positioning an optical element includes a first frame unit and a plurality of support units. Each of the support units has a first end for fixedly engaging a part of the first frame unit and a second end for supporting the optical element. The support units are arranged for positioning the optical element along first, second and third directions in a manner of parallel kinematic. The first, second and third directions being translatory directions arranged mutually transverse to each other. There are provided three support units, each of which provides for restriction of first and second degrees of freedom to support the optical element in an isostatic manner, and one of the support units comprises a movable part bearing an entire fraciton of a load to be taken by the one of the support units.