1550nm 200mW CW DFB Fiber Laser module Manufacturers

Photodiodes are often used as photodetectors. Such devices contain a p-n junction and usually have an intrinsic layer between the n and p layers. Devices with intrinsic layers are called PIN-type photodiodes. The depletion layer or the intrinsic layer absorbs light and generates electron-hole pairs, which contribute to the photocurrent. Over a wide power range, the photocurrent is strictly proportional to the absorbed light intensity.

Recently, Zhang Weijun, a researcher at Anhui Institute of Optics and Fine Mechanics, Hefei Institute of Physical Science, Chinese Academy of Sciences, has made progress in atmospheric nitrogen dioxide (NO2) detection technology. A new method for rapid and sensitive detection of NO2" was published in the American Chemical Society "Analytical Chemistry".

A sensor is a detection device that can feel the information being measured, and can transform the sensed information into electrical signals or other required forms of information output according to a certain rule, so as to satisfy the transmission, processing, storage, and display of information , Recording and control requirements.

Optical coherence tomography is a low-loss, high-resolution, non-invasive medical imaging technology developed in the early 1990s. It combines optical technology with ultrasensitive detectors. Using modern computer image processing, OCT fills the gap in resolution and imaging depth between microscopes and ultrasound imaging. The imaging resolution of OCT is about 10~15 μm, which is clearer than that of intravascular ultrasound (IVUS), but OCT cannot image through blood. Compared with IVUS, its tissue penetration ability is lower, and the imaging depth is limited to 1-2mm.

An optical fiber sensor is a sensor that converts the state of the measured object into a measurable light signal. The working principle of the optical fiber sensor is to send the incident light beam from the light source into the modulator through the optical fiber. The interaction between the modulator and the external measured parameters determines the optical properties of the light, such as the intensity, wavelength, frequency, phase, polarization state, etc. It changes and becomes a modulated optical signal, which is then sent to the optoelectronic device through the optical fiber and passed through the demodulator to obtain the measured parameters. During the whole process, the light beam is introduced through the optical fiber, passes through the modulator, and then emitted. The role of the optical fiber is first to transmit the light beam, and secondly to act as an optical modulator.