US 12,455,415 B2
Signal light transmission member
Hideki Nagano, Saitama (JP)
Assigned to TAMRON CO., LTD., Saitama (JP)
Filed by Tamron Co., Ltd., Saitama (JP)
Filed on Sep. 13, 2023, as Appl. No. 18/367,776.
Claims priority of application No. 2022-167183 (JP), filed on Oct. 18, 2022.
Prior Publication US 2024/0126020 A1, Apr. 18, 2024
Int. Cl. G02B 1/118 (2015.01); G02B 6/32 (2006.01)
CPC G02B 6/325 (2013.01) [G02B 1/118 (2013.01); G02B 6/322 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A signal light transmission member comprising:
a lens that has a refractive index n1 and is configured to collimate signal light;
a housing part that houses the lens;
a light transmission part that has light permeability, has a refractive index n2 smaller than n1, is made of a light transmission material filling the housing part, and has the lens embedded therein;
an optical fiber through which the signal light passes, the optical fiber being inserted into the housing part and having an end portion fixed by the light transmission part at a position facing the lens on an optical axis of the lens in the housing part; and
an anti-reflective coating that is formed at least at a portion of the optical path of the signal light at the interface between the lens and the light transmission part, wherein
if the refractive index of a core material of the optical fiber is designated as n4, a following equation (1) is satisfied:
n4−0.14≤n2≤n4+0.14  (1).