1550nm DFB Fiber Coupled Butterfly Laser Diode Manufacturers

A pump laser is a laser used to provide an excitation light source for a fiber laser or fiber amplifier. The emission wavelength of a 980nm pump laser is approximately 980 nanometers (nm).

A femtosecond laser is an "ultrashort pulse light" generating device that emits light only for an ultrashort time of about one-gigasecond. Fei is the abbreviation of Femto, the prefix of the International System of Units, and 1 femtosecond = 1×10^-15 seconds. The so-called pulsed light emits light only for an instant. The light-emitting time of the flash of a camera is about 1 microsecond, so the ultra-short pulse light of femtosecond only emits light for about one billionth of its time. As we all know, the speed of light is 300,000 kilometers per second (7 and a half circles around the earth in 1 second) at an unparalleled speed, but in 1 femtosecond, even light only advances by 0.3 microns.

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".

Some solid-state laser gain media are doped with transition metal ions, and the transitions involved are those of electrons in the three-dimensional shell. Figure 1 shows the commonly used transition metal ions and their host media.