Title:
OPTICAL SYSTEM, OPTICAL DEVICE AND OPTICAL ELEMENT
Document Type and Number:
Japanese Patent JP2019040115
Kind Code:
A
Abstract:
To provide a safety control system for an optical device when the optical device is subjected to such a temperature condition that is an abnormal condition for the optical device, particularly a high temperature condition, where a part of optical components and optical elements included in the optical device may cause abnormal irreversible optical characteristics.SOLUTION: An optical system includes a light source 10, an optical element 30 that converts the state of light emitted from the light source 10 and exits the light, and a thermochromic element 20 having a thermochromic material layer that is an optical functional layer containing a thermochromic material. The thermochromic element 20 is disposed in an optical path of the light emitted from the light source 10, The thermochromic material layer develops such an irreversible change that, when an ambient temperature exceeds an upper limit θ[°C] and/or a lower limit θ[°C], determined as a predetermined threshold of allowable temperatures, a reduction rate of the transmittance for light at a center wavelength of use wavelengths from the transmittance under a predetermined temperature condition before the ambient temperature exceeds the threshold is 5% or more.SELECTED DRAWING: Figure 1
Inventors:
MIYASAKA KOJI
Application Number:
JP2017163140A
Publication Date:
March 14, 2019
Filing Date:
August 28, 2017
Export Citation:
Assignee:
AGC INC
International Classes:
G02B5/00; G02B5/18; G02B5/20; G02B5/32; G02B21/06
Attorney, Agent or Firm:
Rock wall Fuyuki
Makoto Shiokawa
Makoto Shiokawa