How to distinguish LCD LED OLED QLED?

▲LCD

LCD is the full name of Liquid Crystal Display, mainly including TN, HTN, STN, FSTN, VA, TFT, and other types of liquid crystal displays.

The structure of the LCD is to place a liquid crystal cell between two parallel glass substrates, set a TFT (thin film transistor) on the lower substrate glass, set a color filter on the upper substrate glass, and control the liquid crystal molecules by changing the signal and voltage on the TFT. Rotate the direction, so as to achieve the purpose of controlling whether the polarized light of each pixel is emitted or not to achieve the display purpose.

LCD is a substance between solid and liquid. It cannot emit light by itself and needs an additional light source. Therefore, the number of lamp tubes is related to the brightness of the liquid crystal display.

▲led

LED (Light-emitting diode) light-emitting diode screens. In fact, the images of these displays are still generated by liquid crystals. Light-emitting diodes are only used as light sources. Technically, they are still LCD displays, or LED-backlit LCD TVs.

Liquid crystal (LCD) TV with LED screen has the advantages of small size, low power consumption, long life, low cost, high brightness, long viewing angle, and high refresh rate. The disadvantage is that the color performance is relatively poor, especially when the LCD screen is folded where the color deviation is more pronounced.

▲OLED

OLED (Organic Light-Emitting Diode) organic light-emitting diode, although there is only one letter difference between it and LED, they actually describe completely different things.

We all know that the LCD panel emits light through the backlight, and produces various colors through the refraction of the liquid crystal molecules. The liquid crystal molecules themselves cannot emit light, and the LED only refers to the backlight.

OLEDs, on the other hand, emit light by themselves, so no backlight is required. LEDs are made of metal materials, while OLEDs are made of organic materials. They can emit light without being illuminated by light, and the contrast is better. Usually, LEDs need to be illuminated by a backlight to see things.

At present, the materials used in light-emitting diodes are all inorganic semiconductor materials, which are difficult to apply to large-area and high-resolution components (EX: screens). Solving these problems depends on new organic semiconductor materials (that is, hydrocarbon-containing material), which can be coated on a conductive glass sheet and passed through an electric current to emit light of various wavelengths.

▲QLED

QLED is the abbreviation of Quantum Dot Light Emitting Diodes, which is a self-illuminating technology that does not require additional light sources.

Quantum (Quantum Dots) are some extremely small semiconductor nanocrystals that cannot be seen by the naked eye and are particles with a particle size of fewer than 10 nanometers. Quantum dots have a distinctive feature: whenever stimulated by light or electricity, quantum dots will emit colored light. The color of the light is determined by the composition, material, size, and shape of the quantum dots, and its frequency can be adjusted by changing the size of the quantum dots. , shape, and material to precisely adjust to achieve a variety of applications.