What is nature of light ?
What is Velocity, Frequency & wavelength?
What is Visible Spectrum?
What is Photometry?
Because the eye isnt a reliable means of measuring light, other methods have been developed. This field of science is called photometry.
What is Total Luminous Flux ?
Luminous flux or luminous power is the measure of the perceived power of light. It differs from radiant flux, the measure of the total power of light emitted, in that luminous flux is adjusted to reflect the varying sensitivity of the human eye to different wavelengths of light.
What is Lumens?
The lumen (symbol: lm) is the SI derived unit of luminous flux, a measure of the power of light perceived by the human eye.
How to measure Luminance?
The term luminance is used to describe how bright a lamp appears. Luminance is measured as luminous intensity per unit area of light emitting surface, This is usually candelas per square centimeter (cd/cm2).
What is Illumination & Lux ?