Title:
LIGHT SENSOR AND BAND-PASS FILTER INCLUDED IN LIGHT SENSOR
Document Type and Number:
Japanese Patent JP2023066877
Kind Code:
A
Abstract:
To provide a light sensor enabling suppression of the noise component of light that is received, and a band-pass filter including the light sensor.SOLUTION: According to one aspect of the present embodiment, a light sensor comprises: a light source emitting irradiation light having a wavelength band including a specific peak wavelength to a detection object; a band-pass filter allowing irradiation light having been reflected by the detection object to selectively pass through the filter; a light receiver receiving irradiation light having passed through the band-pass filter; and a measurement device measuring the state of the detection object using the light received by the light receiver. The light source has such a temperature characteristic that a specific wavelength peak of the emitted light shifts for only a first wavelength shift amount due to the ambient temperature. The band-pass filter has such a temperature characteristic that a specific wavelength peak shifts for only a second wavelength shift amount due to the ambient temperature. The shape and material of the band-pass filter are selected in such a way that the second wavelength shift amount and the first wavelength shift amount are equal to each other.SELECTED DRAWING: Figure 1
Inventors:
KOKUSHI WATARU
MIYAI EIJI
MIYAI EIJI
Application Number:
JP2021177718A
Publication Date:
May 16, 2023
Filing Date:
October 29, 2021
Export Citation:
Assignee:
ROHM CO LTD
International Classes:
G01J1/04; G01C3/06; G01J1/02; G01S7/481; G02B5/28
Attorney, Agent or Firm:
Hidekazu Miyoshi
Keishin Terayama
Keishin Terayama