Optical knowledge and noun interpretation of light guide block
[source]: according to different types of light emitting devices / principle, can be divided into point source, line source and surface light source, the typical point light source and a light emitting diode (LED); line light sources such as fluorescent lamp, cold cathode fluorescent lamp (CCFL); OLED, TDEL/ surface light source for EL light emitting device;
[luminous flux]: that is, the rate of light energy emitted by a light source or the rate of light flow, which is the basic quantity for illuminating light source, and the unit is lumen (Lumen). A l00 watt (W) bulb produces l750lm, and a 40W cold white fluorescent tube can produce a 3l5Olm luminous flux.
Luminous intensity: referred to as photometry, it is the luminous flux emitted from a solid angle (unit Sr), that is, the distribution density of luminous flux emitted by light sources or lamps and lanterns in the selected direction of space, and the unit is candlelight (CD). The light luminous intensity of 1CD can radiate the l2.57lm luminous flux.
[illuminance]: the density of the luminous flux on the irradiated plane can be measured by the luminous flux per unit area. LLM luminous flux is uniformly distributed in the L square meter (M2) of the surface, which produce 1 new leuc (LUX, lX) luminous flux illuminance 1lm falling in L square feet (ft2) of the surface, the illumination value of L footcandles (Footcandle, fC). The illuminance of the desktop and working face should not be less than 150lX. The lighting of the living room is ideal with a semi direct light light light fitting, and the average illumination should reach about l00lX. The power of the lamps for reading and writing is larger and the illuminance should reach 200lX.
[color temperature]: in our eyes, most of the light emitted by the light source is commonly referred to as white light. Actually, the white light emitted by different light sources on the naked eye will show different colors due to the color temperature. The blue color, the color temperature is higher the red color temperature is lower. The human eye will sometimes be fooled by their own feeling, feel the difference, but in our photo shoot, you can see the most direct effect, such as shooting in the empty eyes under the pictures may be blue chills, while filming in the light of the photos (not open flash), will have the obvious warm orange red.
[light source efficiency]: the efficiency of the light source is divided by the luminance of its light by the value of its power consumption. The efficiency of light source (Lm/w) = lumen (Lm) / power consumption (W), that is, the amount of light emitted by every watt power. The higher the value, the higher the efficiency of light source, and the more energy saving it is. So efficiency is usually an important factor that we often have to consider.
[type efficiency]: incandescent bulb L5 / quartz halogen lamp 25 /SL power saving fluorescent bulb 65 / mercury lamp 70/ ordinary fluorescent tube 60