3 ports optical circulator Manufacturers

Single-frequency lasers based on Er3+-doped or Er3+/Yb3+ co-doped gain fibers mainly work in the 1.5 μm band (C-band: 1530-1565 nm) and part of the L-band (1565-1625 nm). Its wavelength is in the C window of optical fiber communication, which makes the 1.5 μm band single-frequency fiber laser with narrow linewidth and low noise characteristics very important in coherent optical communication. It is used in high-resolution sensing, optical frequency domain reflectometer , laser radar and other fields also have a wide range of applications.

Thermistors are mainly used for temperature monitoring, overheating protection, etc. It is a temperature-sensitive semiconductor resistor whose resistance changes significantly with changes in temperature. It uses the heat-sensitive effect of semiconductor materials to measure and control temperature, and is widely used in various electronic devices and systems. Thermistors have the advantages of small size, fast response speed, and high measurement accuracy. Therefore, they have been widely used in temperature measurement, temperature control, overcurrent protection and other fields. Text symbols are generally represented by "RT".

The fiber optic sensor network has three basic components, one of which is called a single-point sensor. An optical fiber only plays the role of transmission here, and the other is called a multi-point sensor, where one optical fiber connects many sensors together so that many sensors can share the light source to realize network monitoring. Then there is the smart fiber optic sensor. The multi-point optical fiber sensor is a grating from the outside, and periodic intervals are found through ultraviolet irradiation. When an optical fiber is incident, if the wavelength of the optical fiber is exactly twice the interval, the light wave will be strongly reflected, and if the optical fiber is subjected to temperature changes or strains, the reflected wavelength will change. This kind of sensor There can be many on one fiber, and it can be used for a variety of sensing applications by connecting them.

According to the direction of scattered light propagation, currently common distributed fiber optic sensing technologies are divided into two categories: backscattering distributed fiber optic sensing technology and interference distributed fiber optic sensing technology.

In various optical fiber interference instruments, in order to obtain the maximum coherence efficiency, the polarization state of the optical fiber propagating light is required to be very stable. The transmission of light in a single-mode fiber is actually two orthogonal polarization fundamental modes. When the optical fiber is an ideal optical fiber, the transmitted fundamental mode is two orthogonal double degenerate states, and the actual optical fiber is drawn due to There will be unavoidable defects, which will destroy the double degenerate state and cause the polarization state of the transmitted light to change, and this effect will become more and more obvious as the length of the fiber grows. At this time, the best way is to use Polarization maintaining fiber.