LCD interface types and definitions

LCD interface types and definitions

CVBS composite video signal

Transmission signal: Luminance signal and chrominance signal are superimposed together through spectrum interleaving. Because the luminance and chrominance signals are mixed, the CVBS signal needs to be separated in bright colors, and a good comb filter can obtain high-quality bright color separation. The grooming filter is only useful for bright color separation of TV signals and CVBS signals.

VGA-PC 15-pin VGA input interface

Transmission signal: VGA interface can transmit all signals except 480I/576I signal. The minimum signal standard of the VGA interface is the VGA format (640*480@60Hz progressive), so the VGA interface may not support 480I/576I with too low specifications. Generally, the VGA interface of the projector can accept 480I/576I signals, while the VGA interface of CRT equipment (TV and computer monitors) does not accept 480I/576I signals. The VGA interface contains the I2C bus, so the host and the display device can negotiate and automatically determine the best display format to use, achieving "plug and play".

RGBHV input

RGBHV usually uses 5 BNC or 5 RCA sockets, VW11HT has 5 RCA sockets. If you want to connect the PC's video output to the VW11HT, you need a VGA-5 RCA adapter cable. Transmission signal: RGBHV transmits the same video signal as the VGA interface. Since in the 5 BNC connection, RGB and HV signals are respectively transmitted using a professional BNC cable, unlike VGA, all signals are in the VGA cable, so the transmission characteristics of 5 BNC are better than VGA. Coupled with the good contact performance of the socket (self-contained screwing device), 5 BNC is usually used in the dedicated display field.

VI-Digital Visual Interface

DVI interface due to P&D considering too much "compatibility", and the maximum transmission speed of DFP is limited, VESA has formulated the DVI standard. DVI supports two sets of TMDS signal transmission, up to 2048*1536@75Hz format, so it can be applied to video transmission from ordinary projectors, plasma displays, LCDs to professional workstations. DVI is widely used in projectors and plasma displays. About 30%-50% of mid-to-high-end products have DVI interfaces.

VGA interface

The VGA interface is also known as (S-Dub), which is derived from the input interface of the computer. Since the CRT monitor cannot directly accept the input of digital signals, the graphics card can only obtain the picture by inputting analog signals into the monitor. And VGA is the interface that transmits the analog signal to the display. There are a total of 15 pins on the VGA interface, divided into three rows, five in each row. VGA interface is the most widely used interface type on graphics cards, and most graphics cards have this type of interface.

Both DVI interface and VGA are the most commonly used interfaces in computers. Unlike VGA, DVI is an interface for all-digital transmission, so it guarantees completely uncompressed transmission in terms of image quality. But it does not mean that it is only an interface in a computer. In fact, both VGA and DVI are widely used in other fields, such as digital TV.