US 11,914,205 B2
Coated optical fiber, optical fiber cable, and coated optical fiber ribbon
Minoru Kasahara, Tokyo (JP); Yoshihiro Arashitani, Tokyo (JP); Kouji Mochiduki, Tokyo (JP); and Masahiro Yabe, Tokyo (JP)
Assigned to FURUKAWA ELECTRIC CO., LTD., Tokyo (JP)
Filed by FURUKAWA ELECTRIC CO., LTD., Tokyo (JP)
Filed on Aug. 23, 2022, as Appl. No. 17/821,537.
Application 17/821,537 is a continuation of application No. PCT/JP2021/010778, filed on Mar. 17, 2021.
Claims priority of application No. 2020-047923 (JP), filed on Mar. 18, 2020.
Prior Publication US 2022/0397732 A1, Dec. 15, 2022
Int. Cl. G02B 6/44 (2006.01); G02B 6/02 (2006.01)
CPC G02B 6/4403 (2013.01) [G02B 6/02009 (2013.01); G02B 6/02395 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A coated optical fiber in which a primary layer that covers an optical fiber is formed around the optical fiber, and a secondary layer that covers the primary layer is formed around the primary layer, the primary layer and the secondary layer being formed in this order
wherein an effective core cross-sectional area Aeff of the optical fiber at a wavelength of 1550 nm is 130 μm2 or more, and
wherein, when a coating thickness of the primary layer is P (μm),
a coating thickness of the secondary layer is S (μm),
a thermal expansion coefficient of the primary layer is βP (/K),
an elastic modulus (primary elastic modulus) of the primary layer is PISM (MPa), and
an elastic modulus (secondary elastic modulus) of the secondary layer is SISM (MPa),
a condition of the following equations (I), or
a condition of both the following equations (I) and (II) is satisfied
[Math. 1]
491×10−6≤βP×PISM<600×10−6  (I)
(S/P)×(SISM/PISM)≤1000  (II)