At present, the main video transmission lines on the market include single wire, twisted pair, coaxial cable, etc. Now we will briefly introduce the advantages and disadvantages of video cables in long-distance transmission. Regardless of any cable type, they are used as a conductor for signal transmission. These different types of cables have different quality performances in transmitting different signals. Except for some special applications, the cables currently used for audio and video transmission are mainly single wires, twisted pairs, coaxial cables and optical fibers. DVI extension The main function of the device is to transmit high-definition video signals over long distances. As users have higher and higher requirements for high-definition audio and video information, in order to meet the needs of users for high-quality audio and video, manufacturers of various signal sources, display terminals and intermediate processing equipment have overcome one A difficult problem, launched a series of high-end products. When the main structure of high-definition audio and video signals has been perfected, many manufacturers in the industry also have a lot of tricks on how to make the signal more stable. Usually in engineering installation, the distance between the video source, signal processing equipment and the display terminal cannot be directly connected with the DVI/HDMI cable. Even many equipment manufacturers pursue more stable performance during installation engineering and reduce subsequent maintenance costs. As long as the signal processing equipment is more than 10 meters away from the display terminal, they will no longer directly use the DVI/HDMI cable for direct connection. As a result, many manufacturers in the industry have launched a series of products for extending signal transmission. In response to the current market demand, the same three-dimensional DVI fiber optic extender has launched a variety of specifications, which can transmit 500 meters, 10 kilometers, and 15 kilometers. At present, there are mainly DVI/HDMI long-line transmitters (amplifiers) that use twisted pair cables for transmission. DVI/HDMI optical transceiver and DVI fiber extension module (DVI signal fiber optic transmitter).
Signal transmission extender application
The DVI optical fiber extension module includes two parts: DVI optical fiber receiver and transmitter:
1: Compared with the traditional DVI/HDMI long-line transmitter (amplifier) that uses twisted pair for transmission
(1) Small attenuation, strong anti-interference, high stability, especially not being damaged by changes in the external environment:
We often see flower screens, broken screens, and flickering screens in subway stations, roadside advertising screens, and buses, all of which are caused by unstable signal transmission and damage.
(2) The price is equivalent, the installation is also simple, and the after-sales maintenance cost is lower:
The price of DVI optical fiber extension module is equivalent to that of DVI/HDMI long-line transmitter (amplifier), and the price of optical fiber is also the same as that of twisted pair. At the same cost, the transmission performance can be greatly improved, and at the same time because of stability High can reduce after-sales maintenance and repair costs.
(3) Optical fiber transmission is a development trend, and the standard of display system installation projects is improved, and the winning rate of project bidding is increased.
2: Compared with DVI/HDMI optical transceiver
(1) The transmission performance is consistent, but the RS232 control design is lacking:
The design principles and transmission performance of the two are the same. The optical transceiver is an optical interface module that is independently plugged or welded to the circuit, while the DVI fiber extension module integrates the optical interface module directly into the circuit, so it is more compact and convenient. If the transmission link of the display system only requires signal extension and improved stability, the DVI optical fiber extension module will be more suitable for use.
(2) The price has an absolute advantage.
3: It has DVI-D interface and LC optical interface, and does not have HDMI interface design because in actual use, whether it is a display terminal, an intermediate processing device or a video source, for the convenience of later maintenance, the DVI to HDMI conversion is used The connector is used to connect the module, which can reduce the plugging damage of each device interface.
1. Comply with DVI1.0 standard, support the highest video bandwidth: 1.65Gbps
2. Support resolution: up to WUXGA (1920X1200@60Hz)
3. Transmission distance: 15KM
4. Video interface DVI-D 18+1 pin, optical interface: 2 X LC
5. External fiber type: single-mode fiber
Optical transmission wavelength: single mode 1310nm /1550nm VCSEL
6. Working temperature: 0℃~70℃
Storage temperature: -20℃~85℃
7. Dimensions: 64mm x 42mm x16mm
8. Transmitting power of signal transmitter: -5~0dBm
Signal receiver receiving sensitivity: better than -18dBm
1. Power on the monitor.
2. Connect the DVI fiber optic transmitter to the monitor.
3. Connect the power of the external +5V power adapter to the DVI fiber optic transmitter.
4. Insert a needle into the EDID read-write hole, press the button, wait for 2 seconds, you can see the blue LED light is on for 5-8 seconds, indicating that the EDID read and write succeeded, otherwise, the EDID read and write failed.
5. Unplug the external +5V power adapter.
6. Unplug the DVI fiber optic transmitter and connect it to a signal source, such as a PC.
7. Connect the DVI fiber optic receiver to the monitor and connect the external +5V power adapter.
8. Press the LC port to connect the optical fibers one by one and restart the system, then it can work normally.
The advantages of long-distance signal transmission fiber optic extender transmission medium
1. There is almost no attenuation in the optical fiber, only the lc or sc head itself has a slight attenuation, and this will not cause the influence on the distance, usually within 20dB, which is completely ignored. Unless the distance of this fiber is too long, for example, a multimode fiber with a length of 2.2 kilometers, there will be no signal in transmission. Otherwise, as long as there is a signal, the speed is equivalent to the sending end.
2. Strong anti-interference, zero packet loss rate, no matter how complicated the strong current is coiled around the optical fiber, the transmission speed is always the same. In addition, the probability of packet loss during transmission is almost zero. During the test, 200 finished multi-mode jumpers are used as the trunk, and the telecom software cannot be detected when the machine is full.
3. The service life is very long and the compatibility is high. The general optical fiber on the market can be used for 10 years or more. This copper cable network cable cannot be compared. Moreover, the compatibility is very high. In the high-speed improvement of the future network of optical fiber, whether it is 1M 10M or even the future 10G, 100G, any jumper is universal, and there will be no 5 category 6 like copper cable network cable. There will be no elimination problem if there are more than 10 categories.
4. There is an advantage in cost. According to the general optical fiber in the market at 20 yuan per end, 2 yuan per meter, the cost is not high, and it has an absolute advantage over high-quality category 6 lines
Optical fiber transmission solves long-distance or ultra-long-distance (tens of kilometers) DVI signal transmission, and it is lossless transmission. This allows the extremely difficult problems in many projects in the past to be reasonably solved, and greatly expands the scope of application, such as: The transmission of dvi signals in large-scale occasions such as airports, railway stations, sports centers, shopping malls, and highways can be realized; in many specific occasions, such as occasions with very bad electromagnetic environment, such as warships, substations, power stations, etc. The anti-interference characteristics of optical fiber transmission can be fully utilized, which expands the scope of dvi signal transmission applications.