A novel chip pattern with extinction function in Lead salt detectors is specified. Lead Sulfide (PbS) polycrystalline film is prepared by Chemical Bath Deposition (CMD) on a transparent substrate, then a special figure and structure is saved by lithography techonology on the substrate. As a quaternion detector chip that made by PbS thin film for example in this paper, whose performance including signal, noise, weak-peaks and the uniformity of the chip are too poor to meet the detecting system at the initial stage of research, and the qualified ratio of chips is only 3% .This paper explains the reason why the performance and qualified ratio of chips were so poor, focuses on a novel chip pattern with extinction which avoided the disadvantages of traditional one. the novel chip pattern has been applied in detectors. The novel chip pattern is prepared with PbS thin film which both “extinction slice” and detector chip are based on a same substrate , which not only had absorbed the jumbled light , improved the uniformity and other performance of photosensitive elements, but also had left out the assembly diffculty and precision demand when a extinction slice assembly in the restricted space of inswept detector chip, omitted the production process of extinction slice and shorten the assembly process of the detectors, and the qualified ratio of chips had been improved from 3% to 98%.
High performance narrow band-pass filter(NBF) designed for dual-band infrared(IR) detectors of near-infrared(NIR) and
mid-wavelength infrared(MWIR) application is presented. As the part of dual-color filters, the filter features a high
transmittance at the center wavelength of 1.55μm and a broadband rejection out of the pass band from 1 to 5μm. The
pass band need to be centered in 1.55±0.03μm, have a full width at half maximum of less than 0.055μm and maximum
transmittance higher than 75% when measured at normal incidence. Thin-film design for the filters is investigated in
detail and two kinds of multilayer schemes are obtained by computer optimization. Both consist of a fundamental
narrow-band filter of Fabry-Perot cavity with Si/SiO2 and Ti3O5/SiO2 as the material pair, respectively, and three edge
filters with the material pair of Si/SiO2 for wide band rejection. Moreover, the preparation of the filters have been given,
including the deposition parameters and especially, the optical thickness monitoring of the stack of Fabry-Perot cavity.
Finally, the filters meeting the requirements are accomplished and characterized, which have the peak transmittance of
about 82%, a full width at half maximum of 0.050μm and a broadband rejection with the average transmittance lower
than 1% from 1 to 5μm.