1. Philips Photonics Ltd. 4 New Road, Mitcham, Surrey CR4 4XY, England, UK.
2. Galileo Electro-Optics Corporation, Galileo Park, Sturbridge, Massachusetts 01566, USA.
3. Hamamatsu Photonics K.K. 314-5, Shimokanzo, Toyooka-village, Iwata-gun, Shizuoka-ken, 438-01, Japan.
4. Machinable Glass Ceramic, Corning code 9658.
5. Poly-chloro-tetra-fluoro-ethylene, Fluorocarbon Company Ltd, Caxton Hill, Hertford, England, SG13 7NH, UK.