Class 1 Flashcards
What is light output/luminous flux?
The amount of light created by a light source
How is light output/luminous flux measured?
In Lumens
What does Efficacy (lm/w) measure?
The number of lumens per watts
What does watts measure
Electrical output
What does a high lumen mean?
The higher the lumen, the brighter the bulb.
What is candle distribution?
Describes the amount of candle power a light source gives out at different angles
What is footcandle (fc)?
It is the imperial measure of illuminance
What does 1 footcandle equal?
1 lumen of light equally lighting 1 sqft of surface area at 1ft away from a light source.
What is Lux (lx) ?
The metric unit of illuminance
What does 1 lux equal?
1 lumen of light equally lighting 1 sqm of surface area at 1 m away from a light source
What is color temperature?
A way to describe the light appearance provided by a light bulb
How is color temperature measured?
In Kelvin
Warm light is how many Kelvin’s
3000k-4000k
Day light is how many Kelvin’s ?
4000k-5000k
How many Kelvin’s is cold light
5000k-6000k
What is the range of Kelvin’s that commercial and residential applications use?
2000k to 6500k
What is color rendering index (CRI)?
It measures the ability of a light source to reveal Colors of objects in contrast to a natural light source.
It is the measurement of how you perceive color
What are the CRI levels in percentage
Excellent: 90-100
Good: 60-85
Poor: 0-55
What are the 3 different types of lighting?
- Ambient
- Task lighting
- Accent lighting
What is ambient lighting?
Also known as general lighting, usually the primary source of light in a room
It provides overall illumination and sets the tone for the space
Ex: chandelier, recessed lighting
What is task lighting?
Illuminates the workspaces, helping you to see important detail.
Also important for eye health
Ex: lights under stove hood, under cabinets, table lamps
What is accent lighting?
Also known as highlighting, since it highlights certain aspects of the space.
It adds a dramatic effect to the room and makes it more appealing
Ex: spotlights, lights underneath bookshelves, lights along floor or stairs
