Thermal pad has good heat conduction ability and high level pressure-tolerant, and it is the substitute of thermal grease. Because of having certain flexibility, it has good bonding between a power device and an aluminum heat sink, so it can achieve the best purpose of heat conduction and heat dissipation. In the industry, thermal pad is also called the thermal silica film, thermal conductive silicone pad, insulating heat conducting sheet, soft cooling pad and so on.(more)

Laser is a kind of light source components. In actually, drive circuit refers to modulation circuit of light source device, which plays a role of converting digital signal to optical pulse signal and then sending to fibers. This part is the core of optical transmitter, which decides many important technical parameters.(more)

More recently high-power laser diodes operating in the wavelength range of about 0.8–1.1 micron have been getting much attention due to their widespread applications. These lasers are used in optical pumping of solid-state lasers, such as the Nd: YAG, replacing traditional flash lamp designs. High-power laser diodes are tuned to the absorption band of the dielectric crystal resulting in much more efficient pumping of the laser rod, from which a high-power focused coherent beam of light is emitted. This beam can then be used in a variety of industrial, medical, and military applications. Laser diodes have been developed to match the absorption bands of a variety of dielectric crystals in a broad wavelength range. Figure 6 shows two common variations of high-power laser diode packages.(more)

With the development of science and technology, laser technology has been used in many fields, such as national economy, national defense construction and so on. And it has wide applications in long-distance communications, digital signal storage and recovery, laser ranging, robotics, holographic application, medical diagnosis, etc.(more)

The maximum temperature difference of a single-stage thermoelectric cooler with a standard can reach about 72℃. Some TEC can be stacked together by using mechanical method: the cold side surface of one TEC is installed on the hot side surface of another TEC, so the maximum temperature difference can reach 130℃. This stacking is called the cascade or multi-stage cooler layout. In general, multi-stage cooler has the shape of Pyramid, and a high level volume of TEC is smaller than the low level volume. However, regardless of the shape and the size, the low level TEC need to have a greater cooling capacity than the high level TEC do. Although currently, we have the ability to manufacture more than six or seven level multi-stage TEC, we generally use the two to fourlevel layouts.(more)

c) In order to avoid TECs losing effect due to obvious mechanical vibration, do not place any large mass device without support on the cold end of TECs. When involving lass mass device, it's better to use chucking to fix the TECs between heat sinks and the object. Or place the device on a cold plate that can be media at first. At this time, damping screws can effectively increase the shear strength of the whole mechanical system.(more)

Thermistor is a kind of sensitive element. There are two kinds of thermistors based on different the temperature, which are PTC and NTC. It has a typical characteristic that it is sensitive on temperature. It shows different resistance value when it is under different temperature.(more)

In the system of optical communication, laser driver is an important part of an optical transmitter and it provides enough current to drive laser diode with direct modulation or enough voltage to drive electoral absorption device with indirect modulation.(more)

Thermistor is a kind of sensitive element, and according to the different temperature coefficients, thermistor can be divided into positive temperature coefficient thermistor (PTC thermistor) and negative temperature coefficient thermistor (NTC thermistor). The typical characteristic of the thermistor is sensitive to temperature, and different temperatures show different resistance values. At the higher temperature, the resistance value of PTC thermistor is larger, and NTC thermistor is lower, which belongs to the same semiconductor device.(more)

In the installation process, it's necessary to avoid wrong installation, which makes influence to the TEC modules. There are the following points that may affect the reliability of the TEC modules during the installation:(more)