The Optimum Design Of 2D Micro Angle Sensor Based On Optical Internal Reflection

During the quality guarantee system of modern enterprises, angle measurement takes an important role, and it is also one of the most important parts in geometry measurement fields. With the further development of precision machining and super-high-speed processing, it requires new desire with the online testing precision and speed, and the study of micro angle measurement methods with high accuracy and resolution plays a more and more important role in this field. Nowadays, measurement accuracy and precision have achieved a high level by using various kinds of advanced measurement methods and complicated instruments. However, those traditional angle measurement instruments, such as optic-electronic autocollimator and laser interferometer, can hardly be used as angle sensor in on-line measurement because they are bulky, complicated, expensive, difficult to assemble multi-dimension measuring system and demanding strict work environment.To solve the problem metioned above, based on the effect of the optical internal reflection, a new type of two-dimension micro angle sensor is designed and trail made. This work prepares for the next step of designing and establishing a miniaturization multi-dimension angle and displacement measurement system to make a foundation of realizing the measurement of the moving status or errors of precision machining tool or coordinate measurement machine. Detecting circuit based on high performance MCU MSP430 was used to improve the system speed. To improve the system accuracy, light modulation methods were adopted. Five items listed below show the main work done in this paper.1) The purpose of the study is presented. A large number of references are collected and referred to, an overview of the current national and international situation and developmental trends in the field of micro angle measurement methods is discussed.2) The new angle measurement method based on internal reflection effectiveness discussed theoretically.3) Based on the theoretical analysis, designed a modulated laser diode device, including modulated signal generation circuit and modulation drive circuit. 4) The measurment circuit based on MSP430 has been designed and fabricated. The technical characteristics and performance have been primarily discussed by experiment results.5) The evaluation method of the critical angle sensor is presented. The error factors that affect the measuring accuracy of the measurement system are discussed.