Dust-proof, light-transmitting member and its use, and imaging apparatus comprising same
View Patent ↗A dust-proof, light-transmitting member disposed on a light-receiving surface of an imaging device, comprising a light-transmitting substrate, at least a light-entering surface of which is provided with a dust-proof coating having fine roughness on the surface.
1. A dust-proof, light-transmitting member disposed on a light-receiving surface of an imaging device, comprising a light-transmitting substrate, at least a light-entering surface of which is provided with a dust-proof coating having fine roughness on the surface, comprising at least one selected from alumina, zinc oxide or zinc hydroxide, wherein an antistatic layer is formed under said dust-proof coating and a water-repellant layer with or without oil repellency is formed on said dust-proof coating, wherein said dust-proof, light-transmitting member has spectral reflectance of 3% or less to visible light.
2. The dust-proof, light-transmitting member according to claim 1 , wherein the roughness of said dust-proof coating is constituted by large numbers of fine petal-shaped protrusions irregularly distributed with groove-shaped recesses existing therebetween.
3. The dust-proof, light-transmitting member according to claim 1 , wherein said antistatic layer has surface resistivity of 1×10 14 Ω/square or less.
4. The dust-proof, light-transmitting member according to claim 1 , wherein said a water-repellent layer with or without oil repellency has a thickness of 0.4-100 nm.
5. The dust-proof, light-transmitting member according to claim 1 , wherein said outermost surface has three-dimensional average surface roughness of 1-100 nm.
6. The dust-proof, light-transmitting member according to claim 1 , wherein the roughness of said outermost surface has the maximum height difference of 5-1,000 nm.
7. The dust-proof, light-transmitting member according to claim 1 , wherein said outermost surface has a specific surface area of 1.05 or more.
8. The dust-proof, light-transmitting member according to claim 1 , wherein it comprises a mechanical dust-removing means.
9. A lowpass filter constituted by the dust-proof, light-transmitting member recited in claim 1 .
10. A protective member for an imaging device, which is constituted by the dust-proof, light-transmitting member recited in claim 1 .
11. An imaging apparatus provided with the lowpass filter recited in claim 9 .
12. An imaging apparatus provided with the protective member recited in claim 10 .