Quote: Let's take a look at the VGA case. The full name of the VGA is the Video Graphic Array, which is the display graphics array. VGA supports simultaneous display of 16 colors or 256 shades of gray at a higher resolution of 640X480, while simultaneously displaying 256 colors at 320X240 resolution. VGA quickly became popular due to good performance. This article refers to the address: http:// Let's take a look at the VGA case. The full name of the VGA is the Video Graphic Array, which is the display graphics array. VGA supports simultaneous display of 16 colors or 256 shades of gray at a higher resolution of 640X480, while simultaneously displaying 256 colors at 320X240 resolution. VGA has quickly become popular due to its good performance. Vendors have expanded on VGA, such as increasing the memory to 1M and supporting higher resolutions such as 800X600 or 1024X768. These extended modes are called VESA (Video Electronics). Standards Association, Video Electronics Standards Association's Super VGA mode, referred to as SVGA, now the graphics card and display support SVGA mode VGA interface is the interface of the analog signal output on the graphics card, also known as D-Sub interface. The VGA interface is a D-type interface with a total of 15 pins on the top, divided into three rows, five in each row. The VGA interface is the most widely used interface type on graphics cards, and most graphics cards have such interfaces. The working principle is digitally generated display image information inside the computer, which is converted into three primary color signals R, G, and B and line and field synchronization signals by the digital/analog converter in the graphics card, and the signals are transmitted to the display device through the cable. For analog display devices, such as analog CRT displays, the signal is sent directly to the corresponding processing circuit, which drives the control tube to generate an image. For LCD, DLP and other digital display devices, the corresponding A/D (Analog/Digital) converter should be configured in the display device to convert the analog signal into a digital signal. After D/A and A/D2 conversions, Avoiding some loss of image detail. Now look at the DVI interface. DVI is called Digital Visual Interface. It was composed of Silicon Image, Intel (Intel), Compaq (Compaq), IBM, HP (HP), NEC, Fujitsu (Fujitsu) and other companies in 1999. The figures show the interface standard introduced by the Working Group DDWG (Digital Display Working Group), which is the abbreviation of Digital Visual Interface, and its appearance is a 24-pin connector. The DVI interface is available in a variety of sizes, including DVI-A, DVI-D, and DVI-I, and is designed for digital display devices such as LCD displays. In the process of transmitting analog signals, digital/analog conversion is first performed in the graphics card of the computer, and the digital signals are converted into analog signals for transmission to the display device, and in the digital display device, the analog signals are converted by analog/digital conversion. Convert to a digital signal and display it. After two conversions, some information is inevitably lost, which has a certain impact on image quality. In the DVI interface, the computer directly transmits the display information to the display device by means of digital signals, thereby avoiding the conversion process twice. Therefore, in theory, the image quality of the display device using the DVI interface is better. In addition, the DVI interface enables true plug-and-play and hot-swap, eliminating the need to shut down the computer and display device during the connection process. Therefore, many LCD monitors now use this interface. DVI is divided into DVI-A, DVI-D and DVI-I. 1. The DVI-A port is used to transmit analog signals and has the same function as D-SUB. From the above theoretical introduction, we have clearly understood the advantages of the DVI interface. In the actual use, what advantages does the DVI interface have? To sum up, the DVI interface has the following two major advantages: 1): Fast speed: DVI transmits digital signals. Digital image information is directly transmitted to the display device without any conversion, thus reducing the digital → analog → digital cumbersome conversion process, which greatly saves time. Therefore, it is faster, effectively eliminates smear, and uses DVI for data transmission, the signal is not attenuated, the color is purer and more realistic. 2) The picture is clear: the internal digital signal is transmitted in the computer. If the VGA interface is used to connect the LCD display, the signal needs to be converted into the R, G and B primary color signals through the D/A (digital/analog) converter in the graphics card. And the line and field sync signals, these signals are transmitted to the inside of the liquid crystal through the analog signal line. The corresponding A/D (Analog/Digital) converter is needed to convert the analog signal into a digital signal again to display the image on the liquid crystal. In the above D/A, A/D conversion and signal transmission process, signal loss and interference are inevitable, resulting in image distortion or even display error, and the DVI interface does not need to perform these conversions, thereby avoiding signal loss, so that The sharpness and detail of the image have been greatly improved. Early LCDs, LCDs with DVI interfaces were generally more expensive. At that time, only high-end products had DVI interfaces, but now with the sharp drop in LCD prices, products with DVI interfaces have been priced with only VGA interfaces. The LCD is in line. In this case, why don't we buy products that use this new technology? And DVI will be more and more widely used in future applications. Some LCDs are prone to water ripples when using VGA. Zolition Electronics Co., Ltd. , http://www.szpestrepeller.com
2. The DVI-D port is used to transmit digital signals. The DVI-D interface can only receive digital signals. There are only 3 rows, 8 columns and 24 pins on the interface, and one pin in the upper right corner is empty. Not compatible with analog signals. It is a true digital signal interface.
3. The DVI-I port is used to transmit compatible signals and to transmit analog or digital signals via the active pin definitions on the interface. Among them, the DVI-I port is also divided into single channel and dual channel, which is the 18-pin and 24-pin from the market. The DVI 18-pin DVI belongs to the single channel, while the 24-pin belongs to the dual channel, that is, the 18-pin. The DVI transmission rate is only half of the 24-pin, which is 165MHz. In the screen display, the single-channel DVI supports the same resolution as the dual channel, but the refresh rate is only about half of the dual channel, which will cause the display quality to drop.