OPTICAL ELEMENT AND OPTICAL SYSTEM HAVING THE SAME

Title:

OPTICAL ELEMENT AND OPTICAL SYSTEM HAVING THE SAME

Document Type and Number:

Japanese Patent JP2018045249

Kind Code:

A

Abstract:

PROBLEM TO BE SOLVED: To provide an optical element capable of reducing wavelength dependence of the transmissivity and changes in reflectance due to changes of film thickness in an absorber layer.SOLUTION: An absorber layer 13 is formed over a substrate 11. The transmissivity of the absorber layer 13 varies depending on the position of the substrate 11. The absorber layer 13 also contains a first material and a second material each of which the absorption coefficient having predetermined wavelength dependence. The extinction coefficient of the absorber layer 13 is 0.5 or less in a range of wavelength 400-700nm.SELECTED DRAWING: Figure 1

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Inventors:

KOGA HIRONOBU

Application Number:

JP2017223648A

Publication Date:

March 22, 2018

Filing Date:

November 21, 2017

Export Citation:

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Assignee:

CANON KK

International Classes:

G02B5/00; G02B5/22; G03B11/00

Domestic Patent References:

JP2009288294A	2009-12-10
JP2009092913A	2009-04-30
JP2013148844A	2013-08-01
JP2007178822A	2007-07-12
JP2009244531A	2009-10-22
JP2012163756A	2012-08-30

Foreign References:

WO2007083833A1

2007-07-26

Attorney, Agent or Firm:

Takuma Abe
Sogo Kuroiwa

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