US 12,111,481 B2
Lens and optical component
Akinori Kahara, Osaka (JP); Masato Hasegawa, Osaka (JP); and Toshihiro Yoshida, Osaka (JP)
Assigned to Sumitomo Electric Industries, Ltd., Osaka (JP)
Filed by Sumitomo Electric Industries, Ltd., Osaka (JP)
Filed on Feb. 11, 2022, as Appl. No. 17/669,923.
Application 17/669,923 is a continuation of application No. 15/523,049, abandoned, previously published as PCT/JP2015/080763, filed on Oct. 30, 2015.
Claims priority of application No. 2014-221615 (JP), filed on Oct. 30, 2014.
Prior Publication US 2022/0163698 A1, May 26, 2022
Int. Cl. G02B 5/22 (2006.01); G02B 1/11 (2015.01); G02B 3/00 (2006.01); G02B 5/18 (2006.01); G02B 13/14 (2006.01)
CPC G02B 3/00 (2013.01) [G02B 1/11 (2013.01); G02B 3/0012 (2013.01); G02B 5/18 (2013.01); G02B 5/1876 (2013.01); G02B 5/1895 (2013.01); G02B 13/14 (2013.01); G02B 2003/0093 (2013.01)] 5 Claims
OG exemplary drawing
 
1. An optical component comprising:
a lens having a circular shape when viewed in a plan view, and forming the outermost layer of the optical component; and
a diamond like carbon film covering at least a portion of an entrance surface side of the lens,
the lens is composed of zinc sulfide,
the optical component allows infrared rays having a wavelength of 8 to 12 μm to pass therethrough,
the lens is a diffractive lens,
a surface of the diffractive lens has not more than 0.05 μm of an average value of surface roughnesses Ra in an optical effective area,
the lens has a diffractive surface on an exit surface side, and the lens does not have the diffractive surface on the entrance surface side,
the lens has a bending strength of not less than 10 MPa and not more than 300 MPa, and
the following conditions (a), (b) and (c) are simultaneously satisfied:
(a) lens diameter (mm)≤20×thickness (mm)−50,
(b) the lens has a thickness of more than 3 mm and not more than 7.5 mm at a lens center, and
(c) the lens has a lens diameter of not less than 5 mm and not more than 40 mm.