Title:
OPTICAL SYSTEM AND OPTICAL EQUIPMENT
Document Type and Number:
Japanese Patent JP2015138208
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To provide an optical system capable of reducing ghosts in a wide range without decreasing transmittance performance by using an antireflection film having scratch resistance and good antireflection performance.SOLUTION: The optical system includes a first optical surface where a first antireflection film is formed, and a second optical surface where a second antireflection film is formed. The first and second antireflection films have different reflection characteristics from each other. The first antireflection film includes a first layer containing hollow silica, while the second antireflection film includes a second layer containing hollow silica. The first and second layers each have a refractive index of 1.3 or less with respect to light at a wavelength from 400 nm to 700 nm.
Inventors:
UCHIDA KAZUE
Application Number:
JP2014010874A
Publication Date:
July 30, 2015
Filing Date:
January 24, 2014
Export Citation:
Assignee:
CANON KK
International Classes:
G02B1/11; B32B7/02; G02B13/00; G02B13/04
Attorney, Agent or Firm:
Ryosuke Fujimoto
Atsushi Mizumoto
Hirayama Tomoya
Atsushi Mizumoto
Hirayama Tomoya