New Technique for the Design of an Extreme Ultraviolet Collimator

A mechanical collimator is described which eliminates the problem of internal reflection of off‐axis radiation and is suitable for use at extreme ultraviolet (XUV) wavelengths (approximately 2 to 1500 Å). The collimator consists of a number of identical multiple‐slit arrays, and makes use of the precision of microphotographic fabrication of the slit arrays. A procedure is given for the proper selection of the number and spacing between arrays to prevent cross‐channel transmission of off‐axis radiation [U. S. Patent No. 3,324,294 (6 June 1967)] and a typical application—wavelength discrimination in a satellite XUV spectrometer—is briefly described.