Abstract

A short review of the available neutral density filters is given, with emphasis placed on the evaporation of Chromel A to form a film of any practical density that has neutral transmission throughout the visible and into the infra-red and ultraviolet regions. These films are simple to make and have proved to have good durability, resisting corrosion and rough handling.

© 1947 Optical Society of America

Practical Methods of Making and Using Multilayer Filters

Mary Banning
J. Opt. Soc. Am. 37(10) 792-797 (1947)

Reflection and Transmission Interference Filters Part I. Theory

L. N. Hadley and D. M. Dennison
J. Opt. Soc. Am. 37(6) 451-465 (1947)

A Study Concerning Characteristics of the High-Voltage a.c. Arc

E. A. Boettner and C. F. Tufts
J. Opt. Soc. Am. 37(3) 192-198 (1947)

Infra-Red Filters and Cells of Unpolished Salt Crystals

J. J. McGovern and R. A. Friedel
J. Opt. Soc. Am. 37(8) 660-663 (1947)

Partially Reflecting Mirrors of High Efficiency and Durability1

Mary Banning
J. Opt. Soc. Am. 37(9) 688-689 (1947)