Abstract: A phase-compensating cube comer retroreflector includes three rear reflecting surfaces. All three rear reflecting surfaces can be coated with a phase-compensating film stack that induces 2n? phase difference when handling polarized light. So coated, the phase-compensating cube comer preserves the polarization orientation and ellipticity of the incident light. Such a phase-compensating cube comer can be used to improve the accuracy of distance-measuring interferometers. The cube corner directs light to and from other optical elements, including a polarizing beam-splitters, mirrors, and quarter-wave plates.

Abstract: A phase-compensating cube corner retroreflector includes three rear reflecting surfaces. The first and the third rear reflecting surfaces can be coated with a phase-compensating film stack that induces 2n? phase difference upon reflection, where n is an integer including 0. Alternatively, all three rear reflecting surfaces can be coated with a phase-compensating film stack that induces n? phase difference when handling linearly polarized light, or 2n? phase difference when handling linearly or circularly polarized light. So coated, the phase-compensating cube corner preserves the polarization orientation and ellipticity of the incident light. Such a phase-compensating cube corner can be used to improve the accuracy of distance-measuring interferometers. The cube corner directs light to and from other optical elements, including a polarizing beam-splitters, mirrors, and quarter-wave plates.

Abstract: A method of fabricating a high energy radiation mask, such as a laser ablation mask for manufacturing inkjet printheads, includes a multi-stage evacuation process and/or a step of reducing the deposition rate of silicon dioxide during formation of a dielectric stack. When the multi-stage evacuation procedure is combined with the slower deposition rate of silicon dioxide, the resulting mask has a surprisingly low defect density. In the first embodiment, the evacuation procedure is initiated using a low-rate first evacuation connection. The relatively slow purging of a vacuum chamber in which the dielectric stack is subsequently formed controls turbulence and environmental changes that can generate contamination and water along the surface of the substrate on which the dielectric stack is formed. When a pressure setpoint is reached, a second roughing connection is activated to increase the speed of the procedure. The second connection has a higher maximum rate than the first connection.