US 12,105,320 B2
Plastic wavelength shifting fiber
Masashi Akari, Niigata (JP); Katsuhiro Fujita, Niigata (JP); and Ryuichi Iwakawa, Niigata (JP)
Assigned to KURARAY CO., LTD., Okayama (JP)
Appl. No. 17/630,686
Filed by KURARAY CO., LTD., Okayama (JP)
PCT Filed Jul. 29, 2020, PCT No. PCT/JP2020/029155
§ 371(c)(1), (2) Date Jan. 27, 2022,
PCT Pub. No. WO2021/020478, PCT Pub. Date Feb. 4, 2021.
Claims priority of application No. 2019-139408 (JP), filed on Jul. 30, 2019.
Prior Publication US 2022/0260774 A1, Aug. 18, 2022
Int. Cl. G02B 6/02 (2006.01); C09K 11/06 (2006.01); G01T 1/20 (2006.01)
CPC G02B 6/02033 (2013.01) [C09K 11/06 (2013.01); G01T 1/2018 (2013.01); C09K 2211/1018 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A plastic wavelength shifting fiber comprising:
a core containing a fluorescent agent having a peak of a fluorescence spectrum in a wavelength range of 450 to 550 nm; and
a cladding covering an outer peripheral surface of the core and having a refractive index lower than that of the core, wherein
a sum of a number of carbon atoms of the fluorescent agent and a number of oxygen atoms of the fluorescent agent is 10 to 25, and
a quantum yield QE of the fluorescent agent and an overlap parameter OL thereof defined by a below-shown Formula (2) satisfy a below-shown Formula (1):
OL×(1−QE)<0.07  Formula (1)

OG Complex Work Unit Math
in the Formula (2): Abs(300+2×i) is a relative intensity of an absorption spectrum normalized so that its peak intensity becomes 1; Flu(300+2×1) is a relative intensity of a fluorescence spectrum normalized so that its peak intensity becomes 1; and i is a variable that increases from 0 to 200 by 2 at a time.