Domestic Research And Development Of Laser Airborne Particle Counter (APC)

With the development of such industries as electronics, precision optical machinery processing, war industry, medical treatment, medicines and food production, it is increasingly demanded to control the airborne particles and germ particles in air. As an effective air cleanliness measuring equipment, Laser APC is needed increasingly in market. Because such measuring equipments are mostly imported production, the price is very high and it is very difficult to repair. Owing to the limited factories, low production ability and foreign tradesmen controlling the key and relative parts of Laser APC, it is practical and useful to make domestic research and development of laser airborne particle counter.On the base of analyzing foreign products, the essay puts forward the domestic research and development of the instrument, mainly focusing on the key parts of laser APC——research and development of Optical Transducer——and resolves following questions:(1) Defining the construction of optical transducer in laser APC,——mainly including the selection of light source, design for the lighting system and optical system through studying and comparing analyzing and in the form of right angle optical collecting.(2) Exploring the main construction parts in the APC transducer——the design and processing of ellipse reflective mirror. Under the pre-condition for meeting the instrument's functions, according to the local ability to process ,we can divide the processing into four steps by a series of processing experiments with Ly12 making ellipse reflective mirror----precision numerical control turning shaping, precision grinding, precision polishing and coating high reflective film on turned aluminum mirror---- to modify processing technology and to reduce the cost.(3) Improving the structure of the sample spray mouth because the shape of the spray head has great influence on the floating state of the tested air and making a industrial product designing for the instrument.The laser APC is highly made in China; the key structural and relative partscan be made and bought at home. So the producing cost is decreased greatly. Bythe results of instrument's measuring standard particles, it proved that the designand manufacturing of the product are up to standard and successful. The samplingof air about the product is 2.83L/min; the tiniest particle diameter is 0.3μm; thereare six ways of measuring the particle diameter. Compared with the same ones inforeign country, the product—simple, small and exquisite, beautiful and dignified,convenient to fix and debug, highly precised----has the obvious advantage in price.