US 11,681,153 B2
Antireflection coatings for metasurfaces
Dianmin Lin, Los Altos, CA (US); Michael Anthony Klug, Austin, TX (US); Pierre St. Hilaire, Belmont, CA (US); Mauro Meili, San Leandro, CA (US); Christophe Peroz, San Francisco, CA (US); and Evgeni Poliakov, San Francisco, CA (US)
Assigned to Magic Leap, Inc., Plantation, FL (US)
Filed by Magic Leap, Inc., Plantation, FL (US)
Filed on Jan. 24, 2018, as Appl. No. 15/879,005.
Claims priority of provisional application 62/451,587, filed on Jan. 27, 2017.
Prior Publication US 2018/0217395 A1, Aug. 2, 2018
Int. Cl. G02B 27/42 (2006.01); G02B 1/11 (2015.01); G02B 5/18 (2006.01); G02B 27/01 (2006.01); G02B 1/00 (2006.01); G02B 27/00 (2006.01); G02B 1/111 (2015.01)
CPC G02B 27/4205 (2013.01) [G02B 1/002 (2013.01); G02B 1/111 (2013.01); G02B 5/1847 (2013.01); G02B 27/0093 (2013.01); G02B 27/0172 (2013.01); G02B 27/4272 (2013.01); G02B 2027/014 (2013.01); G02B 2027/0174 (2013.01); G02B 2027/0178 (2013.01); G02B 2027/0185 (2013.01); G02B 2207/101 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A display system comprising:
a waveguide assembly for receiving and outputting image light having image content, the waveguide assembly comprising a stack of waveguides, each waveguide comprising:
an optically transmissive substrate;
an incoupling optical element comprising a metasurface overlying the substrate, the metasurface comprising a plurality of nanostructures forming repeating unit cells, wherein, as seen in a top-down view, each unit cell comprises:
a plurality of first nanostructures having first lengths and first widths, wherein the first lengths are elongated in a first direction, and wherein the first widths differ from one another; and
a plurality of second nanostructures having second lengths and second widths, wherein the second lengths are elongated in a second direction, and wherein the second widths differ from one another,
wherein the second direction crosses the first direction; and
an antireflection coating comprising a layer of an optically transparent material conformally disposed over the nanostructures of the metasurface, wherein the optically transparent material has a refractive index less than a refractive index of the nanostructures, wherein the layer of the optically transparent material follows contours of the nanostructures without completely filling volumes separating each of the nanostructures such that a top surface of each waveguide is non-planar, and wherein the unfilled volumes that separate the first nanostructures from the second nanostructures are of a different volume from the unfilled volumes that separate the first nanostructures or that separate the second nanostructures; and
an image injection device configured to direct the image light into each waveguide of the waveguide assembly via the metasurface of each incoupling optical element,
wherein the antireflection coating has a thickness configured to provide destructive interference between image light reflecting off a top surface of the antireflection coating and image light reflecting off a bottom surface of the antireflection coating,
wherein, as seen in the top-down view, incoupling optical elements of different ones of the waveguides are laterally offset from one another.