Research On Photoresist Particle Counter

Among the many factors that cause a hydraulic system failure,the particulate contaminants in the oil account for more than half cases,so the detection of the degree of oil contamination is a research hotspot in hydraulic systems in recent years.The function of the particle counter is to measure the degree of contamination in the hydraulic oil and detect the concentration of solid particles in the oil to achieve the function of detection and remind to reduce the chance of equipment damage due to oil contaminations.In the research of particle counters,to improve measurement accuracy is the key point to research.Among the factors that cause measurement errors,bubbles in the oil often result in inaccurate particle measurements.Therefore,it is necessary to improve the accuracy of the particle counter measurement and solve the cause of the error caused by bubbles.First,the design of the particle counter's amplifier circuit was designed,and the overall circuit including the transimpedance operation amplifier circuit,differential amplifier circuit(1),band-rejection filter circuit,differential amplifier circuit(2),and logarithmic amplifier circuit was designed.The optical signal generated after passing the detection zone is converted into an electrical signal and amplified to a multiple of the ease of detection.And it focuses on the noise generated by the circuit noise on the amplifying circuit,processing it,and performing the simulation calculation on the filter to achieve noise reduction.Secondly,Zemax software was used to simulate and analyze the light signals generated by the air bubbles in the detection area after being irradiated with parallel light,and the single air bubbles,the coincidence of two air bubbles,the intersections,and the multiple working conditions in the air bubbles were analyzed.According to the above analysis results,a bubble recognition method is proposed.That is,when the bubbles pass through the detection area,an optical signal different from the particle is formed.According to the characteristic,the measurement data result is analyzed and the bubble feature data is eliminated to avoid bubbles.Finally,an experimental test was performed on the designed particle counting platform to test the particle-sized hydraulic oils with particle sizes 4?m,6 m?,and14 m?.The voltage thresholds of the above three particle sizes were measured and measured at different flow rates.The verification experiment of the bubble treatment method was conducted,and the experimental results were compared with the traditional ultrasonic defoaming method and positive pressure defoaming method.The comparison results proved the reliability of the bubble processing method.