Lighting Specifications Flashcards
____ is light emitted from or reflected by an object.
Luminance
Luminance is measured in ____ or ____.
candelas per square meter (cd/m2, also referred to as a nit) or footlamberts (fL).
One nit (cd/m2) = ____ fL.
0.292
____ is light falling on a surface
Illuminance
Illuminance is measured in ____ or ____ .
lux (lx) or footcandles (fc).
One lux = ___ fc
0.09
_____ measures the direct light coming from a source, such as a lightbulb, projector, or monitor.
A. Incident Light Meter
B. Reflected Light Meter
A. Incident Light Meter
____ also known as spot meters, measure the light that bounces off an object, such as a projection screen or work surface.
A. Incident Light Meter
B. Reflected Light Meter
B. Reflected Light Meter
____ is the quantification of the color of “white” light, as rated on a numerical scale.
Color temperature
____ measures the light color that a lamp emits as a single number and indicates the “warmth” or “coolness” of the light.
Correlated color temperature (CCT)
The higher the CCT, the ____ the light. The lower the CCT, the ____ the light.
bluer / redder
The ____ measures how accurately a light source replicates a desired set of parameters. It is the effect a light source has on the perceived color of objects relative to an incandescent source of the same CCT.
color rendering index (CRI)
A lamp’s performance can be measured in lumens per watt. The number of lumens you get per watt is known as ____.
efficacy
A ____ describes the light source and light-producing components (bulb, filament, fuse, and so on).
A. lamp
B. luminaire
A. lamp
A ____ is the light source plus the structures attached to it that control and distribute light (the lamp plus sockets, housing, and so on).
A. lamp
B. luminaire
B. luminaire
Often you’ll hear ____ and luminaire used interchangeably in the AV industry.
lighting fixture
The Illuminating Engineering Society (IES) Lighting Handbook recommends task light levels in AV areas to be from ___ to ___ lux or from ___ to ___ fc.
200 to 500 / 20 to 50
AV designers should specify the amount of ambient light falling on a screen. Front-projection screen recommendation is less than ___ lux.
A. 50
B. 150
C. 200
A. 50
AV designers should specify the amount of ambient light falling on a screen. Rear-projection screen recommendation is less than ___ lux.
A. 50
B. 150
C. 200
B. 150
AV designers should specify the amount of ambient light falling on a screen. Direct display screen recommendation is less than ___ lux.
A. 50
B. 150
C. 200
C. 200
Once you’ve specified your task light levels and your ambient light limits, you can consider the types of lamps and luminaires you’ll want in the room. Lamps can be broken into three main groups.
- Incandescent
- Fluorescent
- LED
_____ work by heating a filament with electricity, which causes the tungsten wire to glow. The advantages are low initial cost and high CRI, while the disadvantages are low efficacy and high heat output.
A. Incandescent Lamps
B. Fluorescent lights
C. LED lights
A. Incandescent Lamps
_____ work by heating both an inert gas and mercury to the point of producing visible light by the phosphor coating on the bulb. The advantages are higher efficacy and cooler operation, while the disadvantages are higher initial cost and sensitivity to external temperatures.
A. Incandescent Lamps
B. Fluorescent lights
C. LED lights
B. Fluorescent lights
_____ work by converting electrical energy directly into photons through semiconductor materials. The advantages are long lamp life, high efficacy, good performance in cold weather, and longer durability. The disadvantages are high initial cost and heat sensitivity.
A. Incandescent Lamps
B. Fluorescent lights
C. LED lights
C. LED lights
