Superfluous or useless light rays, as from a spotlight or other focused light source

A rigid or flexible tape with exposed low-voltage light sources of 1 to 10 watts

A luminaire having a trough-shaped reflector holding one or more fluorescent lamps

A lamp designed to project or diffuse a comparatively uniform level of illumination over a large area

A luminaire consisting of a lamp set in a metal cylinder, recessed into or mounted on a ceiling to direct a beam of light downward

A lamp designed to project a strong, focused beam of light on an object or area

A lighting fixture suspended from a ceiling or wall by a flexible cord, by which it can be raised or lowered

A light source having a maximum dimension less than one fifth the distance from the source to the surface illuminated

A light source having one dimension significantly greater than its other dimensions, such as a fluorescent lamp

A light source having significant dimensions in two directions, such as a large window or a luminous ceiling

A lighting fixture suspended from a ceiling

A decorative lighting fixture suspended from a ceiling, usually having branched supports for a number of lamps

A decorative wall bracket for candles or other lights

A floor lamp having the light source on a hinged, horizontally adjustable arm

A desk lamp having a flexible shaft resembling the neck of a goose

A floor lamp having its light source within a reflecting bowl that directs the light upward

Lighting provided by adjustable spotlights mounted along a narrow, ceiling- or wall-mounted metal track through which current is conducted

Indirect lighting directed upward from an interior cornice at the edge of a ceiling

Indirect lighting directed upward or downward from a light source concealed by a horizontal board or band

Indirect lighting directed downward from an interior cornice at the edge of a ceiling

The science, theory, or method of providing illumination through the use of electric lamps

To emphasize by illuminating with a strong light

Lighting designed to provide a uniform level of illumination throughout an area

Lighting designed to provide a relatively high level of illumination over a small area, with a surrounding area of lower intensity from spill light

Lighting that calls attention to a particular object or feature in the visual field, or that forms a decorative pattern on a surface

Lighting designed to provide strong illumination for a visually demanding activity, such as reading or sewing

The sensation produced by any brightness within the visual field that is sufficiently greater than the luminance to which the eyes are adapted to cause annoyance, discomfort, or loss of visibility

Lighting in which luminaires distribute 90% to 100% of the emitted light downward on the surface or area to be illuminated

Lighting in which luminaires distribute 60% to 90% of the emitted light downward

Lighting from luminaires that emit an approximately equal distribution of light upward and downward

General diffuse lighting in which little light is emitted in the horizontal plane of the luminaires

Lighting in which luminaires distribute 60% to 90% of the emitted light upward

Lighting in which luminaires distribute 90% to 100% of the emitted light upward, esp. to avoid glare or prevent shadows

The regulating by the pupil of the quantity of light entering the eye, resulting in a change in the sensitivity of the eye's photoreceptors to light

A rating of the likelihood that a lighting system will not cause direct glare, expressed as the percentage of people who may be expected to experience visual comfort when seated in the least favorable visual position

The ratio between the luminance of an object and that of its background. Also called contrast ratio.

Reflected glare on a task surface that reduces the contrast necessary for seeing details

To illuminate something from behind in order to enhance depth or to separate the subject from its background

Light coming or produced from the side

Diffuse light that produces little contrast and poorly defined shadows on the subject

Diffuse light that produces high contrast and distinct shadows on the subject

Glare so intense that, for an appreciable length of time after it has been removed, visibility is lost

Glare that reduces visibility or impairs visual performance, often accompanied by discomfort

Glare that produces discomfort but does not necessarily interfere with visibility or visual performance

Glare resulting from a high brightness ratio or an insufficiently shielded light source in the visual field

Glare resulting from the specular reflection of a light source within the visual field

Light originating from sources facing each other, as from windows in opposite walls

Light originating from sources not facing each other, as from windows in adjacent walls

A pipe or tube lined with highly reflective, specular material and designed to transport light some distance from a single point source

A horizontal overhang that shades glazing from direct sunlight below while reflecting daylight through glazing above onto the ceiling of a room and more deeply into a space

Any of various exterior devices for regulating the amount of solar heat and sunlight that enters a window, consisting of movable horizontal or vertical fins controlled manually or operated automatically with time or photoelectric controls

A louvered awning, the metal fins of which are angled to shade a window from direct sunlight and glare while preserving the outside view and admitting soft, diffused light

A manually or electrically controlled exterior venetian blind for protecting a building interior from solar gain and glare

Any of various exterior devices consisting of fixed horizontal or vertical fins angled to shield a window from direct sunlight

A screen, usually of louvers, placed on the outside of a building to shield the windows from direct sunlight

A panel of miniature external louvers for shading a window from direct sunlight and glare while allowing a high degree of visibility, daylighting, ventilation, visual daytime privacy, and insect protection