Lighting Flashcards
(25 cards)
What is the visable Light we can see?
Visible light is the range of electromagnetic spectrum that the human eye can see, typically ranging from 380-700 nanometres, which corresponds to the colours we can see violet to red.
What the light temperatures?
It is a measurement of how warm or cool the colour of a light is. Using the Kelvin scale (K), the lower the value indicates a warmer or yellowed toned light, the higher the value equates to a bluer toned light.
Yellow orange = candle light 900K
Yellow = Warm white 700-3000K
Daylihgt = 800K
Cool white = 700 - 7500K
What are the measurements of light?
Luminous Flux: Luminous Flux: measurement of perceived power of light (in all directions, also termed as ‘radiant flux’). Describes the quality of light emitted by a light source.
Luminous Intensity: describes the quantity of light that radiates in a particular direction.
Illuminance: describes the quality of luminous flux falling on a surface. Relevant standards specify the required illuminance.
Luminance: the measure of the quantity of light that falls on a surface.
What is the definition of LUX?
It is a measure of illuminance: the total amount of light falling on a surface.
Define lumens
It is a measure of luminous flux - the total amount of light emitted in all directions.
Define Luminous Flux
The light emitted by a light source or luminair of received by a surface, respectively, in the direction in which it is distributed. The unit is the lumen (Im)
Define Luminous Intensity
Luminous intensity of a light source in a given direction - The luminous flux emitted by the source in an infinitesimal cone containing the given direction divided by he solid angle of the cone.
The unit is candela (cd)
Define Illuminance
The luminous flux incident on a surface per unit area.
The unit is lux (lx). 1 lx = 1 Im/m2
To meet AS 1680
Define luminace
(at a point on a surface and in a given direction) - The luminous intensity per unit projected area of the surface
The unit used in candela per square metre (cd/m2)
Define the working plane
The horizontal, vertical or inclined plan in which the task lies. Typically ‘desk height” is a horizontal plane 700mm above the floor, of a typical “bench height” at 850mm.
Define brightness
The attribute of visual sensation according to which a surface appears to emit of reflect more or less light
Define Glare
a visual condition which results in discomfort, annoyance, interference with visual efficiency or eye fatigue due to the brightness of a portion of the field of view (lamps, luminaires or other surfaces) being markedly greater than the rest.
What are the types of glare?
- Direct glare (primarily caused by luminaries)
- Reflected glare ( on horizontal visual tasks)
- Reflected glare on vertical tasks (e.g. computer screens)
What is discomfort and disability glare?
Discomfort Glare: which causes discomfort without necessity, impairing the visibility of objects
Disability glare, which impairs the visibility of objects without necessarily causing discomfort.
Define Colour Rendering
A general expression for the colour appearance of objects when illuminated by light from a given source compared, consciously or unconsciously, with the appearance under light from some reference source.
Define Colour Rendering Index
A measure of the degree to which the perceived colours of objects illuminated by a given light source conform to those of the same objects under a reference source.
What is a luminaire?
A light fitting complete with all lamps and other necessary parts and wiring.
What is a lamp?
A generic term for a light source that otherwise might be called a bulb or tube.
What is a troffer?
A luminarie is constructed from an inverted metal trough, most commonly in office buildings, where they are usually inserted into the ceiling grid tiles. Commonly use fluorescent tubes or LED lights.
What are the 3 basic lighting technologies?
Thermal radiation - thermal light sources
Gas discharge - discharge lamps
Electroluminescence - semiconductor light sources
Name some Incandescent Lamps
- General Lighting Services (GLS)
watt range: 15-1500 watts
effective life: 1000 hours
efficacy: 10-15 lumens per watt
phased out in 2009 - Tungsten Halogen
watt range: 10-1500 watts
efficacy: 2000 hours
efficacy: 20-22 lumens per watt
Name some Discharge Lamps
- Fluorescent
watt range: 4-125 watts
efficacy: 7500 hours
efficacy: 60 lumens per watt - Mercury Vapour
watt range: 50-1000 watts
efficacy: 7500 hours
efficacy: 50-55 lumens per watt - Mercury Halide
watt range: 250-1500 watts
efficacy: 10,000 hours
efficacy: 100 lumens per watt - Sodium Vapour: High Pressure Sodium
watt range: 150-1000 watts
efficacy: 16,000 hours
efficacy: 130 lumens per watt - Sodium Vapour: Low Pressure Sodium
watt range: 30-180 watts
efficacy: 6000 hours
efficacy: 170 lumens per watt
Name some LED Lamps
- Light Emitting Diode
watt range: 0.8-15 watts
efficacy: 50,000 hours
efficacy: 100 lumens per watt - Two Types (Red, Green, Blue - tricolour), phosphor-coated
What are the light basics for design?
Visible light
Temperature of light
Measurement of light
Quality of light
Legislative requirements
Amenity and Sustainability
