Light-shielding film for optical element and optical element having light-shielding film

Patent metadata

Field	Value
Publication number	US-2016363701-A9
Application number	US-201514597070-A
Country	US
Kind code	A9
Filing date	Jan 14, 2015
Priority date	Feb 12, 2010
Publication date	Dec 15, 2016
Grant date	—

Abstract

A light-shielding film for optical element includes at least a resin and a colorant. The light-shielding film for optical element has an average extinction coefficient of 0.03 or more and 0.15 or less as an average of extinction coefficients of the whole light-shielding film for light having wavelengths ranging from 400 to 700 nm.

First claim

What is claimed is:

1 . An optical element comprising:
a base material composed of glass or plastic, and a light-shielding film provided on the base material; wherein the light-shielding film comprises a resin and a colorant, wherein the light-shielding film has an interface with the base material, and an interface with air, wherein the light-shielding film has an average thickness of 2 μm or more and 30 μm or less, and wherein the average of extinction coefficient of the whole light-shielding film for light having wavelengths ranging from 400 to 700 nm is 0.03 or more and 0.15 or less.

2 . The optical element according to claim 1 , wherein the light-shielding film further comprises:
(i) non-black particles having an average particle diameter of 100 nm or less and a refractive index (nd) of 2.2 or more, or (ii) inorganic black particles having an average particle diameter of 100 nm or less and a refractive index (nd) of 2.2 or more and 3.5 or less.

3 . The optical element according to claim 1 ,
wherein the colorant contains 20 wt % or more and 50 wt % or less of dye.

4 . The optical element according to claim 1 ,
wherein the colorant contains dye and pigment; and the pigment is composed of at least one selected from the group consisting of carbon black, copper-manganese complex oxide, titanium black, and copper oxide, each having an average particle diameter of 0.1 μm or more and 10 μm or less.

5 . The optical element according to claim 2 , further comprising:
non-black particles having an average particle diameter of 100 nm or less and a refractive index (nd) of 2.2 or more.

6 . The optical element according to claim 5 ,
wherein the non-black particles are titania, zirconia, or a mixture thereof.

7 . The optical element according to claim 2 ,
wherein the colorant is composed of inorganic black particles having a d-line refractive index of 2.2 or more and 3.5 or less.

8 . The optical element according to claim 7 ,
wherein the inorganic black particles are TiN, titania covered with carbon black, titania covered with titanium black, zirconia covered with carbon black, or zirconia covered with titanium black, each having an average particle diameter of 100 nm or less.

9 . The optical element according to claim 1 ,
wherein the ratio of a minimum transmittance to a maximum transmittance, (minimum transmittance)/(maximum transmittance), of the light-shielding film for light having wavelengths ranging from 400 to 700 nm is 0.7 or more.

10 . The optical element according to claim 1 ,
wherein the light-shielding film has a difference in extinction coefficient thereof and is applied to an optical element in such a manner that the side having a smaller extinction coefficient than the average extinction coefficient of the whole light-shielding film is brought into the contact with the optical element.

11 . The optical element according to claim 1 ,
wherein an inner-surface reflectance of inner-surface-reflected light, which is incident light having entered from the side of the optical element and having been reflected at an interface between the optical element and the light-shielding film and at an interface between the light-shielding film and air, at an incident angle of 36.73° is 0.05% or less, the inner-surface reflectance at an incident angle of 45° is 0.07% or less, and the inner-surface reflectance at an incident angle of 68.13° is 1% or less.

Assignees

• Canon Kk

Inventors

• Kubota Reiko

Classifications

• G02B5/003 Primary

  Light absorbing elements · CPC title

• Y10T428/25

  Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles · CPC title

• C09D7/61

  inorganic · CPC title

• C09D7/67

  Particle size smaller than 100 nm · CPC title

• G02B1/04

  made of organic materials, e.g. plastics (G02B1/08 takes precedence) · CPC title