Why 200 yuan street lamp lighting is more yellow and solar street lamps

Street light yellow light mainly consider economy, yellow light is a result not a cause. Street light yellow light is commonly high pressure sodium lamp, the vast majority of photon wavelengths of 555 nanometers, the human eye the wavelengths of light that is yellow. Generally see things under high pressure sodium lamp is depth not



street light yellow light mainly consider economy, yellow light is a result not a cause.

street light yellow light is commonly high pressure sodium lamp, the vast majority of photon wavelengths of 555 nanometers, the human eye the wavelengths of light that is yellow. In general to see under high pressure sodium lamp is different shades of yellow, yes, but now the commonly used high pressure sodium lamp is not a single wavelength, still can show the objects of different colors. Generally we use the color rendering index [ Light source for color is called color rendering of the object, is by reference or reference light source with same color temperature ( Incandescent lamp or light) The comparison of the object color appearance. 】 The indicator light of the features, the sun and the incandescent lamp was out of a possible 100, high pressure sodium lamp is about 20, general metal halide lamp' Ac power metal halide lamp works in mercury and rare metal halide mixed vapor arc discharge in glowing discharge lamp, metal halide lamp is on the basis of high pressure mercury lamp add various metal halide made of the third generation light source. 】 Or energy-saving lamps to more than 60 resolution object color is no pressure. Now also have a high color rendering index for high pressure sodium lamp, such as philips cosmo, while their companies more willing to put the lamp is classified as a metal halide lamp ( Metal halide lamp ( Metal Halide Lamp） Is ac power, working in mercury and rare metal halide mixture vapor arc discharge in glowing discharge lamp, metal halide lamp is on the basis of high pressure mercury lamp add various metal halide made of the third generation light source. 】 。

why use this lamp, because the photoelectric conversion efficiency ( The photoelectric conversion efficiency, namely the incident monochromatic photons - Electronic conversion efficiency ( 单色入射光子- - Electron conversion efficiency, abbreviations IPCE) , defined as the unit of time in the internal and external circuit and per unit time the number of the electrons produced can be the ratio of the number of photons incident monochromatic Np. The mathematical expression formula, IPCE = 1240 Isc/( l Pin) Isc, l and Pin, the use of units of mu A cm - respectively 2, the nm and W m - 2. 】 Commonly used high photosynthetic efficiency high, high pressure sodium lamp 400 - watt bulb in photosynthetic efficiency in more than 140 lumens per watt, elimination of ordinary incandescent lamp in under 10 lumens per watt, household energy-saving lamps, compact fluorescent lamps that highest photosynthetic efficiency are 30 to 40, the higher the same power as the brighter the light efficiency, also is the same brightness can reduce power less inefficient.

a 400 - watt street light to electricity more than 1000 a year, a master in urban areas more than 70000 streetlights.

in addition, high pressure sodium lamp belongs to the gas discharge lamp, unlike incandescent bulbs cannot meet the 220 grid directly, need a inductance ballasts, also need a high voltage pulse trigger, starting current is much bigger than the normal working current, light, need 10 to 15 minutes to reach the normal work of the state, go out to be back in a few minutes later, ionization tube metal sodium cooled to light again, so you see this light conversion efficiency is very high, but not suitable for home.

now in promoting led street lamp ( LED street lamp is made of street lamp, LED lamps and lanterns with high efficiency, safety, energy saving, environmental protection, long service life, fast response speed, high color rendering index of unique advantages, the city lighting energy saving is of great significance. 】