US 12,135,442 B2
Display device with diffraction grating having reduced polarization sensitivity
Vikramjit Singh, Pflugerville, TX (US); Kang Luo, Austin, TX (US); Xiaopei Deng, Cedar Park, TX (US); Shuqiang Yang, Austin, TX (US); Frank Y. Xu, Austin, TX (US); and Kevin Messer, Fort Lauderdale, FL (US)
Assigned to Magic Leap, Inc., Plantation, FL (US)
Filed by Magic Leap, Inc., Plantation, FL (US)
Filed on Mar. 9, 2023, as Appl. No. 18/181,389.
Application 18/181,389 is a continuation of application No. 17/019,065, filed on Sep. 11, 2020, granted, now 11,614,573.
Claims priority of provisional application 62/902,295, filed on Sep. 18, 2019.
Claims priority of provisional application 62/899,673, filed on Sep. 12, 2019.
Claims priority of provisional application 62/899,063, filed on Sep. 11, 2019.
Prior Publication US 2023/0213692 A1, Jul. 6, 2023
Int. Cl. G02B 5/18 (2006.01); F21V 8/00 (2006.01); G02B 27/01 (2006.01)
CPC G02B 5/1842 (2013.01) [G02B 6/0026 (2013.01); G02B 27/0172 (2013.01); G02B 6/0076 (2013.01); G02B 2027/0178 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A waveguide comprising:
a substrate configured to propagate light within the waveguide by total internal reflection; and
at least one diffraction grating on the substrate, each diffraction grating comprising:
a grating pattern on a side of the substrate, the grating pattern comprising material different than the substrate;
a first layer disposed over at least a portion of the grating pattern on the side of the substrate, the first layer comprising an optically transmissive material; and
a second layer comprising metal disposed on the side of the substrate over both the grating pattern and the first layer, such that the first layer is between the grating pattern and the second layer, and such that the diffraction grating has a first diffraction efficiency for light having a first state over a range of angles of light incident thereon and a second diffraction efficiency for light having a second state over the range of angles of light incident thereon,
wherein the grating pattern, the first layer, and the second layer are on the side of the substrate configured as an incident side,
wherein at least one of the first state or the second state is a polarization state, and
wherein the first diffraction efficiency is 1 to 2 times the second diffraction efficiency.