Stray light

[3] ASTM standard E387 describes methods of estimating stray light in spectrophotometers.

There are also commercial sources of reference materials to help in testing the stray light level in spectrophotometers.

[5] In optical astronomy, stray light from sky glow can limit the ability to detect faint objects.

Stray light is a major issue in the design of a coronagraph, used for observing the Sun's corona.

[6] For example: A number of optical design programs can model stray light in an optical system, for instance: Such models can be used to predict and minimize stray light in the final system.