Optical processing apparatus

摘要

An optical processing apparatus utilizing multiple reflections of a light beam between a mask and a reflector has improved uniformity in the distribution of the light beam over a surface of the mask. In one form, the reflector is disposed in a face-to-face relation with respect to the mask with an angle of inclination relative thereto. In another form, the reflector has a flat or curved taper surface for decreasing an angle of reflection of the light beam at the mask surface at an initial stage, and a flat surface disposed in parallel with the mask surface. In a further form, the reflector is curved in a direction of transmission of the light beam. In a yet further form, an angle of incidence of the light beam is properly adjusted such that a portion of the light beam, which is first reflected from the mask and escapes outwardly from the reflector, is minimized.