US 12,282,181 B2
Sensor
Hiroshi Sato, Minamiashigara (JP); Katsumi Sasata, Minamiashigara (JP); and Yukito Saitoh, Minamiashigara (JP)
Assigned to FUJIFILM Corporation, Tokyo (JP)
Filed by FUJIFILM Corporation, Tokyo (JP)
Filed on Oct. 25, 2023, as Appl. No. 18/493,881.
Application 18/493,881 is a division of application No. 17/522,266, filed on Nov. 9, 2021, granted, now 11,835,744.
Application 17/522,266 is a continuation of application No. PCT/JP2020/017296, filed on Apr. 22, 2020.
Claims priority of application No. 2019-090017 (JP), filed on May 10, 2019.
Prior Publication US 2024/0077664 A1, Mar. 7, 2024
Int. Cl. G02B 5/30 (2006.01); G01S 7/481 (2006.01); G02B 5/28 (2006.01); G02F 1/1335 (2006.01)
CPC G02B 5/3016 (2013.01) [G01S 7/481 (2013.01); G02B 5/283 (2013.01); G02B 5/305 (2013.01); G02F 1/133543 (2021.01); G02F 2201/343 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A sensor comprising:
a light source;
a band pass filter; and
a light-receiving element,
wherein the band pass filter includes a first cholesteric liquid crystal layer and a second cholesteric liquid crystal layer that are layers obtained by immobilizing a cholesteric liquid crystalline phase,
in the first cholesteric liquid crystal layer and the second cholesteric liquid crystal layer, helical twisted directions and helical pitches of the cholesteric liquid crystalline phases are the same, each of the helical pitches being a length in a thickness direction in which liquid crystal compounds are laminated in a helical rotation of 360°,
the first cholesteric liquid crystal layer and the second cholesteric liquid crystal layer are in direct contact with each other, and
an angle between optical axes derived from a liquid crystal compound on contact surfaces of the first cholesteric liquid crystal layer and the second cholesteric liquid crystal layer is 45° to 90° within the contact surfaces.