The Design And Error Analysis Of LED Array Illumination Homogenization For Light Field Type Time Gate Angular Displacement Sensor

Angular displacement is one of the most basic physical quantities in measurement,and with the rapid development of advanced manufacturing and measurement fields,precision measurement technology for Angle measurement system precision requirements are more and more high,at the same time,a variety of precision angular displacement measurement devices have been born.For commonly used circular grating angular displacement sensor are grid line processing difficult manufacturing cost is high,and rotating transformer to very difficult to guarantee consistency problems,the author at the early stage of the light field type grating angular displacement sensor based on the research of,further in-depth development from the illuminance distribution of LED lighting uniformity design and error theory research,the main research work is as follows:(1)Carry out research on the design,and simulation source uniformity.According to the characteristics of LED Lambert-type light source,the light source model was simulated with simulation software,and the method of circular array illumination homogenization design was proposed.The homogenization design of the light source with divergence Angle of 7.5° were completed.(2)Theoretical analysis and simulation of light intensity spatial modulation error sources were carried out.According to the error of light source and the error of mechanical structure which causes the spatial modulation error of light intensity,an optimization method combining the design of collimating lens and increasing the number of opposite poles is proposed.The spatial modulation optimization of the system is realized by simulation and verification of the aligning lens and different gate number.(3)Carry out experimental research on light source design and error optimization.The actual effect of LED ring array and collimating lens is verified respectively,and the two kinds of fixing structures with different poles are verified experimentally,and the two kinds of fixing structures with the same poles,single layer and double layer through the grating surface are tested to test the stability of the system.The experimental results show that,after the optimized design of light source,90 pairs of pole-penetration grating surfaces are used in the fixed plate,and the measurement accuracy of ±5.9" is achieved within the 360° whole period measurement range.To sum up,this article through to the LED light source intensity of illumination distribution were studied,the uniformity of the light source design and light emphasis on error theory research,and through the light collimating lens design and change the number of dynamic fixed grid in the face of realize the optimization of spatial modulation signal,realize grating angular displacement sensor light field type to the possibility of a higher precision.