The Design Of Intelligent Instrument For Experiment Of Photoelectric Effect

The rapid development of micro electron technology, computer technology and microcontroller, especially, made traditional electronic measuring instrument having the huge change in principle, function, precision and automation, forming the new generation of measuring instrument ~ intelligence instrument, completely to break through the traditional areaThe photoelectric effect experiment, verifying the Einstein's equation and asking to take Planck the constant, is made by many instruments, out of date in precision, speed and quality of control in experiment. The students must to read a mass data in the experiment taking the survey process longer. The instrument also frequently changes in survey. It brings about a big difference in accurate. There are no functions of image display and real-time observation and control. For the physical experiment automation, opening up student mentality, training student ability of experiment, the intelligent design is made in the equipment for the experimentFor the intelligent design of test equipment of the photoelectric effect, intelligent instrument experiment system using microcontroller is made. This system is mainly composed amplifying circuit, A/D and D/A converters, microcontroller, and computer. The survey process completely is controlled by the microcontroller: the reverse voltage applied to photoelectric cell, produced by the microcontroller, goes through D/A converser. The photoelectric tube produced photoelectric current by light illumination under some frequency that is enlarged by signal enlarging electric circuit, transformed with A/D converser the signal that is collected by the microcontroller. This signal transmits through RS-232 serial communication for computer. The computer carries on the data processing to the signal under the different frequency to make a volt-ampere characteristic curve. The signal of delay time after pressurizing and data collection of photoelectric current is controlled by the microcontroller on time. The period of measuring point is made automatically according program.The system is so practical that it solves the problems of inference on measuring accuracy of the instrument with measuring for a long time and changing of environment, reduces error in experiment and disturbed opportunity of weak photoelectric current to get measuring rapid and accurate.The intelligent instrument for the photoelectric effect experiment is union of new technology (human intelligence, the digital signal processing, the computer science, electronics) and traditional instrument measuring appliance. Along with the developing integration technology for special-purpose, the intelligent instrument will be able to obtain a more widespread application. The microcontroller technology, as an important part of intelligent instrument, is a force making intelligent instrument to miniaturization, multi-purpose. Therefore it will have a widespread application prospect.