Optical element shaping systems
A method for shaping an optical element includes heating a first surface of an optical element, and allowing the first surface of the optical element to cool, thereby causing residual stress in the first surface which deforms the optical element to a predetermined shape. Heating can include applying a laser to the first surface.
1. A method for shaping an optical element, comprising:
heating a first surface of the optical element by applying a first quantity of laser radiation to a portion of the first surface that does not extend to any lateral edge of the first surface, wherein the first surface is a back R2 surface of the optical element that is opposite a second surface of the optical element that is a front R1 surface of the optical element;
applying a second quantity of laser radiation to a third surface of the optical element that is a side surface of the optical element to shape the second surface of the optical element;
allowing the first and third surfaces of the optical element to cool, thereby causing residual stress in the first and third surfaces, wherein the residual stresses shape the second surface of the optical element by deforming the second surface of the optical element,
wherein applying laser radiation to the portion of the first surface comprises applying the radiation directly to the first surface without passing the radiation through the second surface.
2. The method of claim 1 , wherein applying the laser radiation to the portion of the first surface comprises controlling one or more characteristics of the laser radiation to produce a predetermined heating effect and corresponding deformation of the optical element.
3. The method of claim 2 , wherein controlling one or more characteristics of the laser radiation comprises controlling at least one of intensity, beam width, scan rate, and exposure time.
4. The method of claim 1 , further comprising applying the laser radiation to multiple portions of the first surface to cause a predetermined non-uniform deformation of the first surface of the optical element, wherein each of the multiple portions of the first surface does not extend to any lateral edge of the first surface.
5. An optical element, comprising:
an R1 front surface;
an R2 back surface;
a side surface;
a residual stress portion of the R2 back surface that does not extend to any lateral edge of the R2 back surface and has a thickness less than the thickness of the optical element; and
a residual stress portion of the side surface,
wherein the residual stress portions cause and maintain a deformation of the R1 front surface of the optical element by bending the optical element; and
wherein the residual stress portion in the back surface does not extend through the optical element to the front surface of the optical element.
6. The optical element of claim 5 , wherein the optical element is a mirror.