Transmission Type Optical Element
OwnerKatsuhide Shimmoinventor
Life of this patent
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Abstract
The invention relates to a transmission type optical element configured so that a convex/concave structure is formed on a surface thereof, and that incident light to the optical element is subjected to an action at the convex/concave structure. In this optical element, a layer having a convex/concave structure is formed on one of surfaces of a substrate. The transmittance of each of the substrate and the layer having the convex/concave structure at a wavelength of 360 nm is set to be 90% or more so that the transmittance of the layer having the convex/concave structure is equal to or less than the transmittance of the substrate.
Claims8
1-6. (canceled)
A method of manufacturing a transmission type optical element comprising:
- applying a gel solution onto opposite surfaces of a substrate to form coating films;
- pressing a forming die having a convex/concave structure on a first film of the coating films on the opposite surfaces of the substrate;
- pressing a plate-like substrate on a second film of the coating films on the opposite sides of the substrate;
- holding the substrate at a temperature to harden the first film and the second film into respective layers;
- releasing the substrate from the forming die and the plate-like substrate to form the convex-concave structure on the substrate;
- wherein a depth of said convex/concave structure ranges from 0.1 μm to 0.9 μm, and average thickness d1 and d2 of said layers that are respectively formed on both of said surfaces of said substrate and that have refractive indices n1 and n2 at a wavelength λ, at which said transmission type optical element is utilized, are set so that each of values of optical thicknesses n1·d1 and n2·d2 of said layers is within a range defined by an odd multiple of (λ/4)+20%.
Dependencies are inferred from the claim text.