US 12,050,345 B2
Waveguide facet interface
Abu Thomas, Oak Park, CA (US); Andrea Trita, Pasadena, CA (US); and Jeffrey Driscoll, San Jose, CA (US)
Assigned to Rockley Photonics Limited, Altrincham (GB)
Filed by ROCKLEY PHOTONICS LIMITED, Altrincham (GB)
Filed on Mar. 4, 2022, as Appl. No. 17/687,068.
Claims priority of provisional application 63/157,354, filed on Mar. 5, 2021.
Prior Publication US 2022/0283365 A1, Sep. 8, 2022
Int. Cl. G02B 6/125 (2006.01); G02B 6/122 (2006.01); G02B 6/24 (2006.01); G02B 6/12 (2006.01)
CPC G02B 6/125 (2013.01) [G02B 6/122 (2013.01); G02B 6/241 (2013.01); G02B 2006/12119 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A photonic integrated circuit, comprising:
a waveguide; and
a waveguide facet,
a first end of the waveguide being at the waveguide facet,
a first angle being an angle between:
the waveguide at the first end of the waveguide, and
the normal to the waveguide facet,
the first angle being at least 5 degrees,
a first section of the waveguide having a first end at the waveguide facet and a second end,
the first section having:
a curvature of less than 0.01/mm at the first end of the first section,
a curvature of less than 0.01/mm at the second end of the first section, and
a curvature of at least 0.1/mm at a point between the first end and the second end,
wherein the maximum value of the magnitude of the rate of change of curvature within the first section is less than 15/mm2.