The Development Of Semiconductor Laser Characteristic Detection System

With the rapid development of optoelectronic technology, semiconductor laser diode (LD) has been one of the most important components of optoelectronic domain. As the central devices of optoelectronic domain, the performance of the LD is improving continuously, with which the demand for LD characteristic testing is extended. The performance index of LD primarily depends on the testing technology to be ensured. So it is significant and worth studying that testing the characteristics. Based on deep comprehend of the LD basic characteristics, a semiconductor LD testing system was studied deeply in this thesis.The measurement system of LD was made up of PC and measurement instrument of LD and other measurement devices. The paper analyzed the characters and the disadvantages of the existed LD characteristic detection system and puts forward the main functions of the detection systems. The system mainly includes: the study on the physical significance and test methods of the main parameters of LD that includes the photoelectric properties, spectrum properties and so on. This paper designed a semiconductor LD temperature control system.The establishment and realization of the testing system which was base on GPIB interfaces discussion about the construction methods of the detection system platform, which was general opening and in a high testing efficiency; this introduction of the communication on GPIB interfaces, the software exploiting environment, the exploitation of the test software, the disposition of testing data and etc. Aiming at this system's functions, it designed a test software, shows the results and improving plan to the problem in the test. The realization of this system would provide a general establishing method to the measure of LD, mature test means and integrated database management to the detection systems in the field of the LD test.According to actual needs, a semiconductor LD testing system with small size, low price, high precision and flexible operation was developed. The system could drive the wide range semiconductor LD from small to large current and has four control modes, such as ACC, AVC, APC, AMC. At the same time, the system had the function of temperature control with high precision. The essential characteristics parameters of LD, such as LD drive current I_f, drive voltage V_f, output power Po, threshold current Ith of drive current, wavelength and spectrum etc., could be all detected and measured, and the characteristics parameters curve I-L,I-V,I-Im,dV/dI-I,dL/dI-I could be printed. Furthermore, the characteristics TEC could be measured which include temperature , Itec ,Vtec etc.In the process of drawing curves, the testing data was dealed with by smoothing and fitting method. So, the curves become more credible and rational.