Abstract: A system for grading and evaluating optical elements, such as lenses, filters, reticules and the like, where the tested element is scanned by at least one wedge shaped light beam, which has an angle of about 5 degrees to 35 degrees, and which intersects the surface of the optical element in the form of a narrow rectangle, and at an angle with the surface of the element. Beyond the optical element there is arranged a rotating mask which rotates synchronized with the rotating light beam, so that no direct light reaches an array of photoelements positioned beyond the mask, which array receives light pulses resulting from surface defects and internal defects of the tested optical element. The light signals reaching the said array are evaluated and thus the quality of the optical element is deduced.

Abstract: A compact RF excited annular laser system has a stable resonator with a high quality output beam. The stable resonator has internal axiconical and annular mirrors to conform with the annular lasing medium, and to convert the annular beam into a compact cylindrical beam. Mode control is achieved by a combination of diffractive effects in both the annular beam and the compact beam.