Many tests of cell phone jammer will be done in the testing center

 Many tests of cell phone jammer will be done in the testing center.
Under normal circumstances, the semiconductor laser emission wavelength with temperature changes of 0.2-0.3nm / ℃, spectral width increases, affecting the color brightness. In addition, when the forward current flows through the pn junction, fever, loss of the junction of temperature rise, at room temperature near the temperature is increased by 1 ℃, light-emitting semiconductor laser intensity with a corresponding reduction of about 1%, package heat; keep color purity and luminous intensity is very important, in the past to use more ways to reduce the drive current and reduce the junction temperature, the majority of the semiconductor laser drive current is limited to 20mA or so. However, the semiconductor laser light output will increase with the increase of current, present, many power semiconductor laser drive current up to 70mA, 100mA or 1A level, need to improve the packaging structure, a new semiconductor laser package design and low heat resistance package structure and technology to improve the thermal characteristics. For example, using a large area flip-chip structure, selection of good thermal conductivity of silver plastic, metal stents increases the surface area of silicon carrier solder bump directly mounted on the upper heat sink method. In addition, application design, PCB circuit board thermal design, thermal performance is also very important. In the 21st century, high-performance semiconductor lasers, ultra-high brightness, full-color continuous development of innovative, red, orange luminous efficiency semiconductor lasers has reached 100Im / W, green semiconductor laser as 501m / W, the flux alone semiconductor lasers has reached tens of Im.However, the laser threshold current is to allow the laser start-up current, the different cavity length the threshold current can make different semiconductor lasers, such as edge-emitting laser cavity length is longer, the threshold current is relatively large, while the vertical cavity surface-emitting laser cavity length is very short threshold current is very low. These are not one or two words can be said clearly, and their respective rate equations are also different, not one or two formulas can be interpreted. Also different cavity length can be selected to achieve the role model, that is different from the output frequency of the laser. Semiconductor lasers, also known as laser diodes (LD).