The major contribution of fuzzy set theory lies in its capability of representing vague data. Fuzzy logic offers a systematic base to deal with situations, which are ambiguous or not well defined. In the literature, there exist many papers on fuzzy control charts, which use defuzziffication methods in the early steps of their algorithms. Whereas in designing the suggested Fuzzy control chart, a new description of Alpha cut using geometric terms and trigonometric similarity, which is a simple method without using deffusification has been developed for preventing the loss of information included by the fuzzy samples. Accordingly both the samples and the control limits are presented by Fuzzy numbers in whole the charts designing process. Meanwhile in presented thesis the fuzzy process capability ratio was demonstrated for the first time. In the meantime, in other researches no method for determining the Alpha value in designing the fuzzy charts has presented. In this thesis the value of Alpha cut is defined by applying a logical method. From other remarkable topics in this thesis presenting methods for identifying unnatural patterns and the efficiency of the suggested method in calculating the type and error has been evaluated can be pointed out. The suggested approach has been coded applying Dephi7 and powerful software based on the mentioned innovations has been developed. In conclusion the calculated results which gathered from SaIran Electro-Optics Industries (SAPA-Isfahan) have been presented for demonstrating the approach’s efficiency.
