Optical scales, reticles, gratings, masks, and standards

Photofabrication techniques using positive photoresists, developed for the quantity production of theodolite circular scales, have been adapted to making master chrome masks for photoetching moire fringe radial diffraction gratings. Diamond stylus wear, or chipping of the diamond tip, on a precision surface measuring instrument is difficult to detect and can cause incorrect surface texture measurements. A stylus wear standard was developed, and fabrication problems were solved by the anisotropic etching of a silicon slice using a chrome mask and photoresist. An essential feature of this process was precise orientation of the mask with a crystal cleavage plane. Experience gained suggests the means for quantitative quality control of diamond tools used for micromachining.