Filters are core optical elements in various optical instruments. The performance of these filters directly determines the accuracy and reliability of these instruments. Focusing on filters used in fluorescence detection and analysis instruments, their working principle was discussed, and the principles that should be followed when designing these filters were analyzed; the optical coating technology used for filter design and the types of main coating equipment were introduced. Suggestions were given for the selection of coating equipment by comparing and analyzing the advantages and disadvantages of different types of coating equipment. Based on the development and changes of fluorescence detection and analysis instruments, new requirements for these filters were summarized, such as coating on one substrate, more complex spectra, lower wave front distortion, deeper blocking and sharper steepness.