secondary light source

secondary light source

1. A light source which is not self-luminous but receives light and redirects it as by reflection or transmission.
2. The second most important, or most obvious, source of light when several sources are present.
References in periodicals archive ?
Whereas other scanners based on older optical prism technology require a secondary light source to illuminate a fingerprint, LES film actually emits light itself.
The standard approach for CFS in Radiance is to precompute the light passing through each window or skylight, treating it as a "white box" in the final rendering, otherwise known as a "secondary light source." The original mkillum program was written to convert a CFS, described as geometry and materials, into a secondary light source with a luminous intensity distribution corresponding to a particular exterior condition (that is, sun, sky, obstructions, reflections, etc.).
This is why the default method computes a secondary light source (12), leaving the final rendering phase to create a realistic view out the window.
Since we know that windows are important contributors to illumination, we can turn them into secondary light sources, precomputing and smoothing their output distributions for efficient rendering.
If iodine could be induced to fluoresce, it would become an actual secondary light source, and any fingerprints recorded in iodine could be easily isolated and photographed on any background, however dark.
The IQ Lighting[TM] family by Philips Lighting comprises three incandescent bulbs with special features: Auto-Off[TM] turns itself off after 30 minutes; Dimmer lets the user adjust light levels on any fixture without special switches; and Back-up[TM] provides a secondary light source when the main bulb burns out.
These secondary light sources can range from a side or table lamp, torchieres, wall sconces, or track lighting.
Full browser ?