Photoelectric System Design Of The Comprehensive Test Instrument Of Automatic Darkening Welding Goggle Based On New Light Source

The automatic darkening welding goggle is the protective tool that must be worn by the electric welding operators.It can provide a clear and gentle field of view before and after the arcing,which can improve the welding effect and ensure the health and safety of the operators.Shading number,response time,transmittance uniformity and angle dependence are the four most important technical indicators.However,the existing comprehensive measuring instrument can achieve the specified measurement requirements,it can not match the requirements of the inspection department because of its narrow spectral range.Therefore,a new light source is designed by using deuterium lamp and halogen lamp according to regulation of the spectral range of the inspection department,and the photoelectric system of the automatic darkening welding goggle comprehensive measuring instrument is designed.The application circuit of the dual-color detector,the signal processing circuit of the variable gain weak current from nanoampere to milliamperes range and the lower machine program are designed with the single-chip microcomputer as the control core,which realized synchronous detection of dual photoelectric detection signals.In addition,some mechanical structures have been improved.Finally,the spectral range of this measuring system covers 200nm-2000 nm,the light intensity stability reaches ±0.005%.Simulation experiments show that the signalto-noise ratio of the circuit reaches above 110 dB,the response time of the circuit itself is shortened by 3us;moreover,the software part is rewritten to make the function clearer by removing unnecessary programs.Compared with the previous measuring instrument,the measurement system expands the spectral range of the measuring beam,and satisfies the testing requirements of the inspection department,improves the detection accuracy and range of the transmitted light intensity,and further broadens the detection range of the shading number and response time.The detection process of transmittance uniformity and angle dependence is improved.