Gaseous Discharge Lamp - Working Principle and Types: Incandescent lamp suffers from two disadvantages—low efficiency and coloured light. The gaseous discharge lamp have been developed to overcome these drawbacks. The basic principle of a gaseous…

Incandescent Lamp - Construction, Working and Advantages: For sometimes the arc lamps were used for general lighting purpose but as the carbon-arc lamps were complicated so these have been superseded by filament lamps for general…

Arc Lamp -Definition, Working Principle and Types: In an arc lamp electric current is made to flow through two electrodes in contact with each other which are drawn apart. The result is an arc being…

Integrating Sphere in illumination - Construction and Working Principle: It is a piece of apparatus which is now commonly employed for measurement of mean spherical candle power. In this method the sphere is used to…

What is a Photometer and Photometry? - Working Principle and Types: The candle power of a source in any given direction is measured by comparison with a standard or substandard source employing photometer bench and…

Polar Curve in illumination | Rousseau's Construction: Polar Curve in illumination - All discussions made so far were based on the assumption that the luminous intensity or the candle power from a source is uniformly…

Laws of illumination in Electrical: There are two laws of illumination Law of inverse squares and Lambert's cosine law. Law of Inverse Squares: If a source of light which emits light equally in all directions…

What is illumination? - Terms used in Illumination Light is the prime factor in the human life as all activities of human beings ultimately depend upon the light. Where there is no natural light, use…