| 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 the characteristics. Base on deep comprehend of the LD basic characteristics, a LD testing system was studied deeply in this dissertation.Single chip is a important development direction of microcomputer, which has higher integrated rate, highly efficient and cost-effective, greatly reduced dimension and weight. Therefore, it acquire its name by integrating many function components such as CPU, RAM, ROM, EPROM and Input/Output (I/O) interfaces together on one chip.The single chip have the basic function of computer which puts multi-pieces chip on the printed circuit board together The single chip work well as general microcomputer in the application fields which strictly require the volume, the cost, the power loss, the real-time control and so on, Even the microcomputer can not take the place of single chip. It has been widely applied in the field of small intelligent instrument, industry real-time control, intelligent terminal, telecommunication equipment, automobile, farm machinery, household electric appliance and children toy.As the MCS-51 series single chips have the merits such as various kinds, strongly compatibility, cheap price, complete application software and the mature development technology, nowadays it plays important part in the industry domain of intelligent instrument measuring appliance, medical instrument, household electric appliance consumption and computer external instrumentation.Charge-coupled device (CCD) is a new semiconductor device proposed in 1970's. For 30 years, it is surprisingly that the research and the application of this device has rapidly developed, and moves quickly from experimental stage towards practical stage. Now, CCD has become one of the most actively and productively emerging field of modern photo-electronics and the modern test gathering technology. For CCD have a series advantage of non-contacts, highly accurate rate, highly sensitivity, easily computer processing, easy connected with automatic control equipment and so on, from the beginning of the 1990's, using CCD as data acquisition technology, is a extremely effective non- contact examination method which is widely used in kinds of parameter inspect instrumentation. Therefore we developed the system to gathering laser semiconductor's parameter with CCD.There are mainly two kinds of the traditional semiconductor laser parameter gathering test system. One depends on the spectrograph to gather the data, another takes step-by-step motor machine as the internal core which is connected with the grating. When the photosource arrive in the diffraction grating, light of different wavelength reflect to different directions. depending on step-by-step motor machine in each period of time causing the grating rotate to certain angle, which will beam a component of light launching from an eyelet shinning to PMT (photo multiplier tube), and the data will be carried on by PMT gathering.with the development of photo electricity semiconductor technology, CCD (Charge-coupled device) and the solid detector gradually applied in the photo electricity examination and the spectral analysis. Their performance not only as good as PMT, but also have the function of simultaneously multi-channel examination.Although the Miniature spectroscope integrated by the grating and the miniature CCD has less-sensitivity, the volume is smaller and the cost is low, and it can work long hours under the room temperature. Moreover, compared with the spectrograph and PMT, using CCD can conveniently connect to the photosource and the computer through the optical fiber input, USB or the serial data communication interface, and the most of all, it has the function of multichannel simultaneously examination, which can provide with two dimensional and even the three dimensional photoelectricity information in the extremely short time, thus enhanced the efficiency.In the paper first introduced the research background and the significance of semiconductor laser, and elaborated laser both domestic and foreign research course of the semiconductor and the its latest achievement. Base on this foundation, it is detailed discussed about the semiconductor laser module structure, the principle of the laser shone, the shines principle of semiconductor laser, related characteristic parameter analysis and the test method of semiconductor laser. With correlated introduction, the goal and the related researched content of the paper are determined.Main idea of the paper is to gather (V-I) and photoelectric characteristics (P-I) characteristic parameter of semiconductor laser with CCD, with the modulus switch carrying digital-analog conversion, then, correlation processing with data is transmitted from the lower position machine to top position machine(computer) through the serial communication. Of course the whole process is under the control of MCS-51 single chip. Main content is: the choice of CCD apparatus and the design of actuation; the choice of modulus switch and the design of actuation; the realization of serial communication function; the control of input power source's current adjustment with single chip and the D/A converter; semiconductor laser electric current control's choice and the hardware's design,manufacture ,debugging, Semiconductor laser voltage source's design, manufacture and debugging; software of top position machine's design and development work.Finally, we carried on the overall debugging and did the experiment for the system. From the calculation result it is showed that the system can work well with the data's acquisition, conversion, transmission and can carry on the corresponding data processing in the top position machine, and give the parameter diagram of V-I, the P-Is curves. The design had achieved the anticipated target, satisfied the design request. |
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