US 12,038,606 B2
Optical device and photodetection system
Akira Hashiya, Osaka (JP); Yasuhisa Inada, Osaka (JP); and Masanori Era, Kumamoto (JP)
Assigned to PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD., Osaka (JP)
Filed by Panasonic Intellectual Property Management Co., Ltd., Osaka (JP)
Filed on Sep. 29, 2021, as Appl. No. 17/488,391.
Application 17/488,391 is a continuation of application No. PCT/JP2020/016394, filed on Apr. 14, 2020.
Claims priority of application No. 2019-089232 (JP), filed on May 9, 2019.
Prior Publication US 2022/0019022 A1, Jan. 20, 2022
Int. Cl. G02B 6/12 (2006.01); G01S 7/481 (2006.01); G02B 6/124 (2006.01)
CPC G02B 6/124 (2013.01) [G01S 7/4817 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An optical device comprising:
a first mirror having a first reflecting surface and extending along a first direction;
a second mirror having a second reflecting surface that faces the first reflecting surface and extending along the first direction;
an optical waveguide layer, located between the first mirror and the second mirror, that causes light to propagate along the first direction, wherein:
a transmittance of the first mirror is higher than a transmittance of the second mirror,
a reflection spectrum of at least either the first mirror or the second mirror with respect to light arriving from a direction normal to the reflecting surface includes, in a wavelength region in which a reflectance is higher than or equal to 90%, a local maximum point and first and second points of inflection located closer to a long-wavelength side than the local maximum point, and
a reflectance monotonically decreases on a long-wavelength side of the local maximum point to at least the second point of inflection.