LEDs Test Method: Luminous Flux and Luminous Efficiency
Method 2003: Luminous Flux and Luminous Efficiency 1 Objective Measure the luminous flux and luminous efficiency of LED device being tested under the rated condition. 2 Test Chart Picture 9 Method 2003 test chart Note 1: the optical radiation lunched by the LED device under test has been reflected many times through the integral wall [...]
Theories About Light Part2: Photometry and Luminous flux
Photometry Photometry is the light measurement, which is defined as electromagnetic radiation detectable by the human eye (daylight). It is thus restricted to the wavelength range from about 380 to 780 nanometers (1000 nm = 1 μm). Photometry is just like radiometry except that everything is weighted by the spectral response of the eye. Visual [...]
Basic Theories About Goniophotometer Part2: High Accuracy Measurement for Luminous Flux
2. High accuracy measurement method for luminous flux of luminaries and lamps The derivation of luminous flux from a measurement of illuminance distribution of a light source is the method which can usually achieve very high accuracy. The measurement principle can be expressed as: φ=∫E*dS (s) This is also the method for many developed countries [...]
Photometric Terms
Luminous flux: Φ, Lm Luminous flux is the sum total of the amount of light per second generated by the illuminant. Light intensity: I, cd The luminous intensity is the luminous flux from a point source emitted per unit solid angle in a given direction. A goniophotometer can be used for measuring light intensity. Illuminance: [...]
