What Is The Difference Between LCD Module And LCD Panel?

Liquid crystal module (LCM) is simply the LCD screen and backlight assembly. For example, the display component of an LCD TV is a liquid crystal module, and its low temperature is equivalent to a picture tube in a CRT. Other parts include power supply circuits, signal processing circuits, etc., and of course the casing.

Liquid crystal modules are mainly divided into screen and backlight components. The two parts are assembled together but work independently of each other. The principle of liquid crystal display is that the backlight component emits light, and the light is displayed through the liquid crystal screen. The role of the LCD screen is to control and process these lights on a pixel-by-pixel basis to display images.

The LCD panel is the main component of the LCD and accounts for nearly 80% of the cost of the LCD. At present, there are not many manufacturers with panel manufacturing technology in the world. Only SHARP (Sharp), Samsung, LGD, Innolux, AUO and other manufacturers have core technologies. In the past, most terminal manufacturers used their LCD panels. Of course, with the rapid development of mainland panel manufacturers, domestic companies such as BOE, Shentianma, CSOT, etc. have also begun to accumulate their own patented technologies, and the panels produced by them are also widely used by terminal manufacturers.

What is the difference between LCM and LCD panel

LCD panel specifications and grades

The so-called dead pixel is a general term for pixels that cannot be displayed normally on the LCD panel. The liquid crystal panel is composed of many pixel points, and the liquid crystal material on each display point is completed by changing the light transmission and the same state under the control of electric signal. At 1024*768 resolution, the LCD panel has a total of 786,432 display points, so it is difficult to completely guarantee that there will be some problems with so many points. At present, the technology cannot completely overcome the occurrence of no dead pixels. Therefore, the level division of the panel is also judged according to the number of dead pixels. Manufacturers generally avoid dead pixels and divide LCD panels, selling LCD panels with no dead pixels or very few dead pixels at a high price, while those with a large number of dead pixels are dealt with at a low price.

At present, the main grading standards for panels are:

Korean manufacturers, less than 3 are A-level

Japanese manufacturers, less than 5 are A-level

Taiwanese manufacturers, less than 8 are Class A

Key indicators of mainstream LCD monitor brands:

AA grade: LCD display without any dead pixels is AA grade.

A-level: 3 dead pixels or less, no more than one bright spot, and the bright spot is not in the central area of the screen.

Class B: 3 dead pixels or less, including no more than two bright spots, and the bright spots are not in the central area of the screen.

In addition, the quality of the liquid crystal panel is related to the resolution, brightness, response time, visibility, contrast ratio and the like of the liquid crystal panel. The control ICs, filters and directional films used in the manufacture of liquid crystal panels are closely related to the contrast ratio of the panel. For ordinary users, a contrast ratio of 350:1 is enough, but in the professional field, such a contrast ratio is not enough. user needs.

Brightness is also a more important indicator. The brighter the liquid crystal is, it stands out from a row of liquid crystal walls when viewed from a distance. The principle of LCD display brightness is realized by the brightness of the backlight tube behind the panel.

The response time refers to the response speed of the liquid crystal display to the input signal, that is, the response time of the liquid crystal from dark to bright or from bright to dark, usually in milliseconds (ms). Response time is as short as possible.

The viewing angle of the liquid crystal When the backlight passes through the polarizer, the liquid crystal and the alignment layer, the output light has directionality. So far there are three more popular techniques, namely: TN+FILM, IPS (IN-PLANE-SWITCHING) and MVA (MULTI-DOMAIN VERTICAL alignMENT).