| 摘要 |
FIELD: narrowband filtration covers. ^ SUBSTANCE: narrowband filtration cover contains two systems of alternating dielectric layers with different refraction coefficients and equal optical thickness lambda0/4, in the form of high reflection mirrors, and a dielectric layer dividing them. In accordance to the invention, structure of high reflection mirrors additionally features dielectric layers with intermediate value of refraction coefficient and dividing layer has optical thickness lambda0 or one divisible by it, and sequence of layer alternation has form (CBCABA)KD(ABACBC)K with nA<nB<nC, where refraction coefficient of dividing layer nD is not equal to nA (for example, nD=nC) and k>=1 is an integer number, where: lambda0 - maximal filtration cover throughput wave length; A, B and C - dielectric layers with values of refraction coefficient nA, nB and nC respectively, and D - dividing layer. ^ EFFECT: increased selectivity due to expansion of high reflection bands on the sides of pass band. ^ 5 dwg |
