Serveral Common Fiber Optic Devices Wiki

1. Fiber Coupler

Fiber Optic Coupler, also called fiber optic adapter, is used for connecting and coupling of optical fiber connectors. According to the connection header of optical fiber connector to select model. The joint structure can be divided into: FC, SC, ST, LC, MTRJ, MPO, MU, SMA, DDI, DIN4, D4, E2000 forms, with good sintering technology to ensure excellent strength and stability (200 ~ 600gf insertion force).
Applications Of Fiber Optic Coupler
Fiber communication network
Broadband access network
Optical CATV
Optical instruments
LAN
2. Fiber Termination Box

Cable termination box, also known as optical fiber termination box or fiber termination box, is a connection device between several cores cables and termination equipments, mainly used to fix the cable termination, store and protect the remaining fiber optics, the splicing of fiber optic cable and fiber pigtail.
3. Fusion Splicer

Fusion splicer, the connection of two optical fiber cables, should joint the fiber inside the cable, because the fiber is just like glass, must re-fused special joint on the two ends, then the ends melt together, so that the light signal can be passed.
Light transmitting in fiber causes a loss, this loss is mainly composed of transmission loss of optical fiber itself and the splicing loss at optical fiber joints. Upon the order of optical cable, its own fiber optic transmission loss is also basically identified. The fiber joints splicing loss is determined by fiber optic itself and on-site construction. Efforts to reduce the optical fiber joints splice loss, can increase the transmission distance of optical fiber amplifier and improve the attenuation margin of fiber link.
4. Fiber Media Converter
Fiber optic media converter, is an Ethernet transmission media conversion unit to interchange the twisted-pair electrical signal of short distance and light signal of long distance.
Fiber converters are generally used in actual network environment where Ethernet cable can not cover and must use fiber optic to extend the transmission distance, the access layer application and usually located in metropolitan area networks; while it also plays a huge role in helping the fiber at the last kilometer connecting to the metro network and more outer layer network.
5. Fiber Optic Multiplexer
Fiber Optic Multiplexer is a fiber communication equipment to extend data transmission, it is mainly through the signal modulation, photoelectric conversion technology, using the optical transmission characteristics to achieve the purpose of remote transmission. Optical multiplexer generally used in pairs, divided into optical transmitter and optical receiver, optical transmitter completes the electrical/light switching, and optical signal is sent for optical fiber transmission; optical receiver mainly converts the light signals from the fiber receiver back into electrical signals, completing the light/electricity conversion. Optical multiplexer is used for remote data transmission.
Optical multiplexers are divided into many types, such as telephone optical multiplexer, Video Multiplexer, Video Audio Multiplexer, Video Data Multiplexer, video Audio Data Multiplexer and so on. And commonly used is Video Multiplexer (especially widely used in security industry).
Optical multiplexer is the terminal equipment of light signal transmission. Its principle is: a photoelectric conversion transmission equipment; put at both ends of the optical cable; one transmitter and receiver, just as its name implies multiplexer. So optical transmitter and receiver are used in pairs, usually buy optical multiplexer is said to buy a few pairs, instead of several.

Video Multiplexer Using High Speed Amplifier

In the past few years, the number of video sources connected to a single display has increased steadily, make the video signal switching must in most video system. In a typicaly home entertainment systems, for example, a set-top box (STB) or digital video recorder (DVR) cable or statellite TV, VCR, DVD players, a video game console, and a PC all feed a single display. The ability to switch multiple video sources to a single display extends to cars as well, where video sources include the vehicle entertainment system, rearview camera, DVD player, navigation system, and auxiliary video input.

Traditional CMOS multiplexers and switches suffer several disadvantages at video frequencies, where their on resistance introduces distortion, degrades differential gain and phase performance, and interacts with the terminal resistor to the attenuation of the incoming video signal and affect intensity. System designers to solve this problem by adding external buffer added gain, increasing the drive capability.

Video multiplexing can be simplified by using high speed video amplifiers with a disable mode. When the optical amplifier is disabled, its output stage into a high impedance state. This is different from their low power consumption mode, greatly reduces the power consumption, but leave the state of the output stage is undefined.

High-speed video amplifiers have all the key features required to make them ideal for this function. Their high input impedance does not affect the characteristic impedance of the transmission line, thus allowing back termination. Because they are video amplifiers, they have inherently good video specifications, including differential gain and phase, slew rate, bandwidth and 0.1-dB flatness.

In a mux configuration, the disabled channels present a high-impedance load to the single active channel. The gain setting and feedback resistors load the active amplifier, but their values are large compared to the 150-ohm video load, so their effect is negligible.

3:1 Video Multiplexer

Video multiplexer is used to encodes the multi channel video signals and convert them to optical signals to transmit on optical fibers. The ADA4853-3 has independent disable controls, making it suitable for use as a low-cost 3:1 buffered -output video mux. Its output impedance is greater than 2-kohms at 10 MHz, so the amplifier outputs can be connected to form a 3:1 mux with excellent switching behavior and great isolation characteristics. Operating on a single 5-V supply, the configuration shown in Figure 1 provides 14-MHz bandwidth (0.1-dB), gain of +2, and 58-dB off-channel isolation at 10 MHz. Its 10-μs channel-to-channel switching time supports CVBS analog video applications.

Figure 1. 3:1 Video Multiplexer

High-Performance 2:1 Video Multiplexer

Figure 2 shows a high-performance 2:1 mux. The two input amplifiers are configured as unity gain followers, while the output amplifier is set for a gain of +2. The ability to shut-down both stages allows this mux to achieve the excellent input-to-output off-isolation shown in Figure 3. Switching time in this configuration is 45 μs.

Conclusion:

High-speed video amplifiers with a single disabled needle is very suitable for simple structure, low cost video multiplexers and switches for compound and high resolution video. They are the ideal replace CMOS switch, it is more cost effective than video multiplexer. Be sure to consider using high-speed video amplifiers if your system requires video switching function.