| 摘要 |
PROBLEM TO BE SOLVED: To provide an ND filter and a light quantity diaphragm device capable of suppressing the deformation of a substrate due to the internal stress of the filter, capable of suppressing the transmission in a visible wavelength region, and also, capable of reducing the transmitted light quantity in a near infrared wavelength region, and to provide a camera equipped with the light quantity diaphragm device. SOLUTION: A thin film 2 having characteristics of attenuating the transmission of a visible region is arranged on a substrate 1 having characteristics of suppressing the transmission of the light in the near-infrared wavelength region as compared with the transmission of the light in the visible wavelength region. In this case, the substrate can be constituted of an infrared cut glass and a resin infrared cut filter or the like, and the thin film can be constituted of a thin film having either of mono-density, multi-density, and gradation in terms of density distribution. COPYRIGHT: (C)2006,JPO&NCIPI
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