roundel

Alternate spelling of rondel.

Also spelled roundel, and usually pronounced "ron-dell".
A rondel is a circular glass color media used in compartmentalized striplights or borderlights, sometimes called X-Rays.

Kopp Glass was/is probably the most common manufacturer.

Colors are limited to Primary Red/Blu/Grn, Amber, and Clear. Historically, other colors including yellow/canary, surprise pink and no color blue were available. Diameter varies from about 3" to 8"; the most common is 5-5/8" which fit the AltmanR40striplight (and similar) as well as many older 'A-lamp' styles.




Smooth:


Stippled:


"Lenticular-Lined" 50° Spread:


While some may refer to them as lenses, rondels have no magnifying power, although are available in a variety of finishes: smooth, stippled, and 50° spread.

The lenticular-lined spread rondel works like R104 Tough Silk, spreading the light only in one axis, perpendicular to the lines..