LIGHTING TERMS Flashcards
- lamp invested by a Swiss named Argand in 1783
- had a round wick with provision for the intro. of air inside the wick as well as around the outside
Argand Lamp
- oil lamp with swinging the tubular arms, generally furnished with an a Argand burner
- used in the early 19th century
Astral Lamp
-the process by which the eye adjusts to a change in light level
Adaptation
-general light, often indirect, or entering a room from an adjacent space
Ambient Light
-an opaque or translucent element used to shield a lamp from view or to absorb unwanted light
Baffle
-a device used with HID and fluorescent lamps to establish the circuit conditions necessary to start and operate the lamp
Ballast
-an unshielded light source
Bare Lamp
-glare so intense that cannot se for a short period of time
Blinding Glare
- any artificial light source, concealed behind a decorative facing, which allows the light to diffuse over its edges, and through it, if the facing is translucent be recessed into ceiling or wall can be direct, indirect, or semi-direct
- cove and valance lighting are examples
Concealed Light
-the difference in luminance between an object and its background
Contrast
-an optical filter that selectively reflects some wavelengths, while transmitting others
Dichroic Mirror
-one that appears scattered, either in reflection or transmission
Diffuse Reflector
-a device used to regulate the intensity of light from a lamp
Dimmer
-this is light that is focused and forced to travel in a particular direction either by a reflector or baffle
Directional Light
-glare the reduces visibility and visual performance
Disabling Glare
-annoying glare but often does not reduces visibility and visual performance
Discomfort Glare
-recessed or semi-recessed lighting unit with a rotating spherical element that may be turned to project light in any direction below the ceiling line
Eyeball
-a way of transmitting light through long flexible glass or plastic fibers, using the principle of total intern refraction
Fiber Optics
-a device to change, in transmission, the quality of light affecting the magnitude and or spectral make-up
Filter
-the emission of light, only during the absorption of radiation of a different wavelength
Fluorescence
-the density of a light on a surface
Illuminance
-a lighting unit which, by means of lenses and mirrors, concentrates light in a limited angle and intensifies it
Projector
-a general term used to describe devices that block, diffuse or redirect light such as a louver or lampshade
Shielding
-a term applied to any stray light outside the main concentration of the beam, usually controlled by louvers, baffles. etc.
Spill Light
-glare,, where reflection reduces contrast and so prevents detail being discerned
Veiling Reflection
-usually the horizontal surface at which a task is performed and at which light levels are specified and measured
Work Plane
