Film thickness of vacuum coating machine measuring and monitoring method

   

  Coating control method is the most direct method of quartz crystal micro balances (QCM design),the instrument evaporation source of  vacu​um coating machine can be directly driven by the PID control loop drive baffle and the rate of evaporation. As long as the instrument and system control software, it can control the whole process of coating. Coating machine (QCM design) accuracy is limited, however, partly because of its monitoring instead of the optical thickness of the coating quality. In addition, although the QCM design is very stable at low temperature, the temperature is high,so it would be very sensitive to temperature. After a long period of heating process, it is hard to avoid sensors for sensitive areas and lead to significant errors film.
  Optical monitoring is a kind of high precision coating optimization control mode, the vacuum coating machine can accurately control the thickness of the membrane (if used properly). The improvement of accuracy, due to many factors, but the most fundamental reason is the monitoring of optical thickness. Optimalswa - I - 05 single wavelength optical monitoring system, coating machine is indirect control, advanced optical monitoring software in combination with the development of Dr Wong, effectively improve the sensitivity and change the light reaction of film thickness to reduce the ultimate method of error theory, provides monitoring wavelength feedback or the choice of transfer mode and extensive. Especially suitable for coating a variety of thin film thickness monitoring including irregular membrane.