| Film technology is very important in the Optoelectronic field. From the points of the spectrum characteristics of the optic film, optimum design of the multi-layer film, error analyses of the film, monitoring method and the actual coating technology, detailed theoretical analyses and experimental research have been done for the four key types of filter used in WDM system. The design and manufacture of the various filters are the most useful and difficult technology in the field of optical information science. The main contributions of this thesis are listed as following: (1) A set of perfect film error analyses and coating process simulation was founded in this thesis. Monte Carlo simulation can obtain the range of the controlling precision for the film thickness, tolerance on the thickness of the each layer was obtained by dynamic sensitivity analysis; the possible compensation relation between each layer of the film was obtained by the analyses of the Admittance Chart; by modeling the optical monitoring process we can find out whether the monitoring process can be completed. The method of error analyses presented in this thesis is systemic and perfect, and is applicable to the analysis of other optical film. The experimental results confirm the theory analyses. (2) The strategy of controlling the film thickness was made to coat various filter film. A mixed monitor method was used in coating narrow band filter, maximum value monitor method for the reflected and interval layer, coupling layer by the method of quartz crystal oscillator, the outer layer was monitored by the method of quartz crystal oscillator and optical method. It is impossible to reach the technique parameters for the WDM filter only by the method of maximum value monitor. The Edge filter and PBS were monitored by the maximum value method. It can reduce the error by changing the monitor wavelength to convert all the layers to nonregular layer without any change of the film structure. The relative sensitivity of film layer has reduced to only one tenth after the wavelength conversion, and the productivity was greatly improved. (3) The optical monitor unit in Leybold APS1104 has been investigated and improved, the bandwidth of the monitor light is less than 0.3nm, the optimum bandwidth and intensity of the monitor light were decided by calculation and large amount of experiments. (4) Deep researches have been done for the testing method of the narrowband filter, and the testing system was established. Agilent8164A, which was operated manually before was modified to be an automatic testing system for the narrowband filter. Compared to the other testing system, the test speed has been improved several times, and it is easy to operate, the measure accuracy is ±1pm. The testing system not only can test the narrowband filter, but also can measure all optic signals (1550nm waveband) in the optic communication field. (5) Deep research was done to design and manufacture film Polarized Beam Splitter Prism (PBS) with small size, high extinction ratio, high cut-off degree. A high extinction ratio and cut-off degree device was obtained by the film design and coating method; reasonable cold machining process can make the prism with suitable dimension; the parallel angle between the input beam and the output s and p beam is less than 30 second, this was guaranteed by the special monitoring light path and optimum online glue worktable. In conclusion, the DWDM 100GHz narrowband filter with four cavities, the CWDM narrowband filter with 9 cavities, several types of interference edge filter in 1315nm/1550nm waveband and a micro-polarized beam splitter (PBS) have been designed and fabricated successfully in this thesis. Several WDM thin-film components with technique specifications in the international advanced level were made, and there are no reports on the micro PBS prism. Through the discussions on the fabrication of the Ta2O5, Nb2O5, SiO2, VO2, ITO thin film, the function of material doping and the film post annealing technique on the fabrication of WDM narrow band filter have been discussed in this thesis.
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