Main types of light source lifting lamp

Time：2021-03-24 View：

Main types

 

Lighting source
The illumination light source is an electric light source that radiates visible spectrum (wavelength 380 ~ 780nm) mainly for human vision for the purpose of illumination. Its specifications are various, with power ranging from 0.1W to 20kW, and its output accounts for more than 95% of the total output of electric light sources.
There are many kinds of lighting sources, which can be divided into three types according to the form of light emission: heat radiation light source, gas discharge light source and electroluminescent light source.
① heat radiation light source. The current flows through the light source of conductive objects to radiate light energy at high temperature. Including incandescent lamp and tungsten halogen lamp.
② gas discharge light source. Electric current flows through gas or metal vapor to generate a light source that emits light due to gas discharge. There are two kinds of gas discharge: Arc discharge and glow discharge, and three kinds of discharge voltage are low pressure, high pressure and ultra high pressure. Arc discharge light sources include: Fluorescent lamp, low pressure sodium lamp and other low pressure gas electric-discharge lamp, high pressure mercury lamp, high pressure sodium lamp, metal halide lamp and other high intensity gas electric-discharge lamp, ultra high pressure mercury lamp and other ultra high pressure gas electric-discharge lamp, and arc lamp carbon, xenon lamp, some spectral light sources and other gases with large discharge pressure span electric-discharge lamp. Glow discharge light source includes glow indicator light source using glow discharge in negative glow region and neon light using glow discharge in positive column region, both of which are low pressure electric-discharge lamp; In addition, some spectral light sources are also included.
③ electroluminescent light source. Under the action of electric field, the light source that makes solid matter glow. It directly converts electric energy into light energy. Including electroluminescent light source and light emitting diode.

 

Radiation light source
Radiation light source is an electric light source that does not aim at illumination and can radiate a large amount of ultraviolet spectrum (1 ~ 380nm) and infrared spectrum (780~1 × 106nm), including ultraviolet light source, infrared light source and visible light source for non-illumination. The above two types of light sources are non-coherent light sources. In addition, there is a kind of coherent light source, which emits light through excited particles under the action of stimulated radiation, and outputs the wavelength of light wave from short wave ultraviolet to far infrared. This light source is called laser light source.

 

Stable light source
In fiber optical communication technology, light source is an indispensable signal source for measuring optical fiber attenuation, connection loss, active connector loss and sensitivity measurement of optoelectronic devices or optical receiver.

 

Principle of stable light source
Stable light source, that is, its output optical power, wavelength, spectral width and other characteristics (mainly optical power) should be stable and unchanged. Of course, absolute stability is impossible, only under given conditions (such as a certain environment and a certain time range), its characteristics are relatively stable. To meet certain index requirements, stable light source should have certain measures to ensure the stability of its characteristics. Generally, measures such as ECC (automatic power control) circuit and ATC (automatic temperature control) circuit are adopted.

Backlight
The most core technology in light source module is the optical technology of light guide plate, which mainly includes printing form and injection molding form. Other forms such as injection molding and printing, laser marking and corrosion account for a small proportion, not suitable for mass production principles. Printing form has become the mainstream technology for a long time because of its low cost, but its main disadvantage is that the qualified products are not high, and LCD products require more precise light guide plate structure, injection molding light guide plate is bound to become the mainstream of backlight development, but only a few large factories can overcome the corresponding mold technology problems. The optical technology of the light guide plate of Weizhi company mainly adopts two forms of light guide plate: printing shape and injection molding shape.
Backlight there are mainly three types of backlight according to the light source type: EL, CCFL and LED, which are divided into side light type and straight down type (bottom backlight type) according to the different light source distribution position. The following is a brief introduction to them.

 

Edge light type
The linear or point light source is set on the side of the specially designed light guide plate made of backlight. According to the needs of actual use, it can be made into two-sided or even three-sided. The side light backlight can generally be made very thin, but the light utilization rate of the light source is relatively small, and the thinner the utilization rate is smaller, the maximum is about 50%. Its technical core is the design and manufacture of light guide plate. The most commonly used side light type are LED light backlight and CCFL backlight. Weizhi LED side light type backlight has WU, WH, WN class as single side type, WL, WJ, WK, and WB class as double side type. With the continuous development of LCD modules in the direction of brighter, lighter and thinner, side-light CCFL backlight has become the mainstream of the development of backlight. WQ products are Weizhi CCFL edge light backlight.

 

LED light backlight
LED lights are also called light emitting diodes. Compared with other light sources, the power consumption of a single LED light is minimal. From blue to red, LED lights have many colors, such as "Table 1" and "Table 2". In addition, another special color is white, "Table 3" shows its commonly used chromaticity range. In various colors, it can be roughly divided into two types: bright and low bright: basically, "Table 1" is low Bright (although Amber, orange and red are also slightly highlighted), "Table 2" and "Table 3" are highlighted.
Since White is a mixed color and has no marked wavelength value, it is expressed by its coordinate value on the chromaticity diagram. We customize it as "cold white" and "warm white. In all kinds of colors, there is the problem of color deviation, among which blue and white are more obvious, especially white, and LED suppliers cannot effectively control them.

 

CCFL backlight
The biggest advantage of this kind of backlight is high brightness, so black and white negative phase, blue mode negative phase and color liquid crystal display parts with larger area basically adopt it. Theoretically, it can make various colors according to the color matching principle of three primary colors. The disadvantage is that the power consumption is relatively large, and the inverter circuit needs to be driven, and the working temperature is relatively narrow, between 0 and 60 degrees, while LED and other QITADE backlight can reach between-20 and 70.

 

Bottom backlight
It is a flat surface light source with a certain structure, which can be a continuous and uniform surface light source, such as EL or flat fluorescent lamp; It can also be composed of more point light sources, such as Dot Matrix LED or incandescent lamp backlight. LED dot matrix and El backlight are commonly used.

 

El backlight
That is, Electroluminescence is the cold light illuminator that emits light by the intrinsic luminescence of fluorescent powder under the excitation of alternating electric field. Its biggest advantage is thin, which can achieve a thickness of 0.2~0.6mm. Disadvantages are low brightness, short service life (generally 3000~5000 hours), inverter drive is required, and flicker, noise and other defects will occur due to circuit interference. EL drivers include inverter and DriverIC drivers. Because the frequency and load output voltage of DriverIC cannot reach the typical conditions of EL (400Hz, AC100V), the brightness is lower than that of inverter drive. White Light (full color) EL and LCD backlight are also available one after another. However, because the brightness is dark, it is basically used for small-sized liquid crystal display below 4 inches. Such as mobile phones, PDAs, and game consoles. Full color (white light), large size brightness backlight, the mainstream is still using CCFL as the light source. Wei Zhi did not develop EL backlight.

 

LED bottom backlight
The advantages are good brightness and uniformity. The disadvantage is that the thickness is relatively large (greater than 4.0mm), the number of LEDs used is relatively large, and the heating phenomenon is obvious. Generally, low-light colors are used for design, while bright colors are basically not considered due to high cost. WA products are Weizhi bottom backlight.
Electric light source refers to a device or device that converts electric energy into light energy. Widely used in daily lighting, industrial and agricultural production, national defense and scientific research, etc.