Abstract

Synthetic fused silica, Dynasil, is widely used in modern optics because of its special optical characteristics is widely. UV transmittance and optical homogeneity are two of its most important qualities. A study of UV transmittance has resulted in determination of the distribution of that characteristic in the manufactured boules. The profile of the area in the boules where UV transmittance exceeds 80% (for 185 nm wave length and 10 mm sample thickness) has been determined, and strict quality-assurance procedures have been implemented. The accuracy of optical homogeneity measurement performed on fine ground silica blanks (oil-on-plate technique) with ZYGO MarkII ZAPP interferometer has been studied. The systematic error of the measurement (bias) was found to be 1/30 of a wavelength for a 4 in. (10.16 cm) aperture and 1/15 of a wavelength for 12 in. (30.48 cm) aperture; the data scatter was about 30% of the bias value.

© 1990 Optical Society of America