LOW PASS FILTER AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a low pass filter which can easily control optical performance with sufficient accuracy and which can be easily manufactured at a low cost and with stable quality and is suitable for mass production. SOLUTION: The low pass filter 10 includes a structure 10A which is constituted by two-dimensionally arranging projection-shaped lens bodies 13 on a base material 11 at about definite pitch P and an intermediate body 15 which is arranged in a trench 14 in a state where the trench 14 between the lens bodies 13 of the structure 10A is buried. The lens body 13 is formed of a first material and the intermediate body 15 is formed of a second material. When d(μm) denotes the depth of the trench and▵n denotes the difference between a refractive index of the first material and a refractive index of the second material, a value of d×▵n(μm) is in a range between 0.20 and 0.60 and the pitch of the lens body is in a range between 1.0μm and 100μm. COPYRIGHT: (C)2009,JPO&INPIT