shade glass

shade glass

[′shād ‚glas]
(optics)
A darkened transparency that can be moved into the line of sight of an optical instrument, such as a sextant, to reduce the intensity of light reaching the eye.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Outside (above), angled west wall has roll-down dlinds to shade glass from summer sun; stucco blends addition with existing exterior
The manufacturers say the Blue Shade Glasses will make food look "dull and boring" because blue is the least appetising colour on the spectrum.