Week 22

Progress:

4.1.5 Color Rendering Index (CRI)

Color Rendering Index represents he quality of light and its faithfulness to render colors correctly that is to enable human to perceive colors. The ideal CRI is 100 and some bulbs approach this level. LED bulbs rating ranges from 70 to 95.

Light Source	CRI Index
Fluorescent Lamp	52-95
Incandescent Lamp	~100
HID (mercury)	15-55
LED	0-80

Table 4.2: CRI index for lighting devices

4.1.6 Correlated Color Temperature (CCT)

Correlated Color Temperature is the measure used to describe the relative color appearance of a white light source. CCT indicates whether the light source appears more yellow or gold or orange or more blue, in terms of the range of available shades of white. CCT is given in Kelvin (unit of absolute temperature). 2700K is Warm and 5000K is Cool.

4.1.7 Lumens

Lumen is a unit of standard measurement that is used to describe the amount of light contained in an area as perceived by the human eye. The more lumens, the brighter the light.

4.1.8 Luminous Flux

Luminous Flux is the flow of light measured in lumens. With light bulbs, it provides an estimate of the apparent amount of light the bulb will produce. Depending on the application, much of an incandescent light is wasted because it is emitted in every direction. LED bulbs, on the other hand, put out directional light, sending all of the light exactly where it is needed.