What's the difference between WLED and LED?

WLED is a kind of LED, especially white LED. The standard WLED of conventional displays in the market is called professional error prevention at best, and DT at worst. To put it bluntly, basically all the LED backlight displays you see on the street are WLED. Will the desktop monitor with RGBLED really be less than five-digit RMB …

Cold cathode fluorescent lamp (CCFL).

2.2 composition. CCFL

1. 1. connector: connect the inverter.

1.2. Iron frame: protecting and fixing lamps.

1.3. Nylon rivet: fixing lamp tube with light guide plate, reflector, diffuser, etc. ? camera lens

1.4. Light guide plate: light guide

1.5. Heat shrinkable sleeve: fix the high-voltage conductor, insulate and protect the exposed electrode terminal.

1.6. High voltage conductor: conducting electricity.

1.7. Lamp silver reflective paper: reflecting the lamp light and leading it into the light guide plate.

The characteristics of 3.3. CCFL

3. 1. Light weight, thin and light plane.

3.22. Uniform lighting, high efficiency and high brightness.

The cold cathode lamp tube (as shown in figure 1) is sealed in a glass tube with inert gas Ne+Ar mixed gas. The glass tube contains a small amount of mercury vapor (several milligrams), and the inner wall of the glass is coated with fluorescent powder. A high-voltage and high-frequency electric field is applied between the two electrodes, so that the mercury vapor is excited in this electric field to produce an energy release and luminescence effect, and ultraviolet light with a wavelength of 253.7nm is emitted. At the same time, phosphor atoms on the inner wall are excited by ultraviolet light to improve their energy levels. When atoms return to their original low energy levels,

thin film transistor

Thin film transistor (TFT) means that each LCD pixel is driven by a TFT integrated behind it. So as to display screen information at high speed, high brightness and high contrast. TFT belongs to active matrix liquid crystal display.

Supplement: TFT(thinfilmtonist) refers to the thin film transistor, which means that each liquid crystal pixel is driven by the thin film transistor integrated behind the pixel, so that it can display screen information with high speed, high brightness and high contrast. It is one of the best LCD color display devices at present, and its effect is close to CRT display. It is the mainstream display device on notebook computers and desktops. Each pixel of a TFT is controlled by a TFT integrated on itself and is an active pixel. Therefore, not only the speed can be greatly improved, but also the contrast and brightness are greatly improved, and the resolution has reached a very high level.

TFT (thin film transistor) screen is also widely used in high-end color screen mobile phones at present, which is divided into 65536 colors, 260,000 colors and160,000 colors, and the display effect is excellent.

WLED

WLED white light emitting diode

It means white LED.

Basic knowledge of led

LED is the abbreviation of light emitting diode, which is translated as "light emitting diode" in Chinese. It is an electronic device that can convert electric energy into light energy and has the characteristics of a diode. At present, different light emitting diodes can emit light with different wavelengths from infrared to blue light, and there are also white LEDs coated with fluorescent powder to convert blue light into white light.

Color and technology of LED: Different materials can produce photons with different energy, thus controlling the wavelength of light emitted by LED, that is, spectrum or color. The material of the first LED in history was gallium arsenide (As) (Ga), and the light emitted was infrared spectrum. Another commonly used LED material is gallium phosphide (Ga), which emits green light.

Because gallium, arsenic and phosphorus are used in the manufacturing process, these LEDs are usually called ternary LEDs. The blue led of GaN, the green LED of GaP and the infrared LED of GaAs are called binary LEDs. At present, the latest technology is a quaternary LED made of AlGaInN quaternary materials mixed with aluminum (Al), calcium (Ca), indium (In) and nitrogen (N), which can cover all the spectral ranges of visible light and part of ultraviolet light.

Luminous intensity:

Luminous intensity is measured by lux, lumen and candlelight.

1CD (candle light) refers to the luminous intensity of a completely radiated object per sixtieth square centimeter at the freezing point of platinum.

1L (lumen) refers to the luminous flux of 1 CD candle shining on a plane with a distance of 1cm and an area of 1cm.

1Lux (lux) refers to the illuminance where the luminous flux of 1L is evenly distributed on the area of 1m2.

The active luminous body generally adopts the luminous intensity unit candle CD, such as incandescent lamp and LED. Reflecting or penetrating objects use luminous flux unit lumen L, such as liquid crystal projector; Luminance unit Lux is generally used in photography and other fields. The three units of measurement are equivalent in value, but they need to be understood from different angles. For example, if the brightness (luminous flux) of a liquid crystal projector is 65,438+0,600 lumens, and its projection size on the total reflection screen is 60 inches (65,438+0 square meters), its illuminance is 65,438+0,600 lux, assuming that its light outlet is 65,438+0 cm away from the light source and its light outlet area is 65. However, due to the loss of light propagation, the loss of reflective or light-transmitting film and the uneven distribution of light, the brightness of a real LCD projector will be greatly reduced, and the efficiency of 50% is generally good.

In practical use, data units that are easy to map or change direction are often used in light intensity calculation. For LED display screen, which is an active luminous body, CD/ m2 is generally used as the luminous intensity unit, and the observation angle is used as an auxiliary parameter, which is equivalent to the illuminance unit lux on the screen surface. Multiply this value by the effective display area of the screen to get the luminous intensity of the whole screen at the perfect angle. Assuming that the luminous intensity of each pixel in the screen is constant in the corresponding space, this value can also be regarded as the luminous flux of the whole screen. Generally, the brightness of outdoor LED display screen must reach more than 4000 CD// m2, in order to have ideal display effect in the sun. Ordinary indoor LED, the maximum brightness is about 700~2000 CD//m2.