US 12,124,052 B2
Dynamic incoupling gratings in imaging systems
Jahja I. Trisnadi, Cupertino, CA (US); Pierre St. Hilaire, Belmont, CA (US); and Clinton Carlisle, Parkland, FL (US)
Assigned to Magic Leap, Inc., Plantation, FL (US)
Filed by Magic Leap, Inc., Plantation, FL (US)
Filed on Feb. 24, 2021, as Appl. No. 17/184,039.
Application 17/184,039 is a continuation of application No. PCT/US2019/048642, filed on Aug. 28, 2019.
Claims priority of provisional application 62/723,688, filed on Aug. 28, 2018.
Prior Publication US 2021/0255471 A1, Aug. 19, 2021
Int. Cl. G02B 27/42 (2006.01); G02B 27/00 (2006.01); G02B 27/01 (2006.01); H04N 9/31 (2006.01)
CPC G02B 27/4205 (2013.01) [G02B 27/0081 (2013.01); G02B 27/0172 (2013.01); H04N 9/3155 (2013.01); G02B 2027/0123 (2013.01)] 19 Claims
OG exemplary drawing
 
1. An eyepiece for projecting an image light field to an eye of a viewer, the eyepiece comprising:
a waveguide configured to propagate light via total internal reflection (TIR) inside the waveguide between a first surface of the waveguide and a second surface of the waveguide opposing the first surface;
a dynamic input coupling grating (ICG) formed as an integral part on the first surface of the waveguide in a first lateral region of the waveguide and configured to diffract light into the waveguide as a TIR beam;
a light source configured to generate a light beam transmitted to the dynamic ICG;
a controller coupled to the light source and the dynamic ICG, the controller being configured to:
modulate an intensity of the light beam in a sequence of time slots, each time slot of the sequence of time slots corresponding to a respective field angle of a pixel in the image light field, the intensity of the light beam in each time slot of the sequence of time slots corresponding to an intensity of the pixel in the image light field at the respective field angle; and
control the dynamic ICG to, for each time slot of the sequence of time slots, diffract a respective portion of the light beam into the waveguide at a respective angle corresponding to the respective field angle of the pixel prior to propagation by total internal reflection inside the waveguide; and
an exit pupil expander coupled to a second lateral region of the waveguide and configured to direct each respective portion of the light beam out of the waveguide toward the eye of the viewer at the respective field angle, thereby projecting the image light field to the eye of the viewer.