Lightweight eyepiece for head mounted display

摘要

An eyepiece includes an eyepiece frame, an in-coupling polarization beam splitter (“PBS”), an end reflector, and an out-coupling PBS. The eyepiece frame defines an air cavity and includes an illumination region for receiving computer generated image (“CGI”) light into the eyepiece frame and a viewing region to be aligned with an eye of a user. The in-coupling PBS is supported within the eyepiece frame at the illumination region to re-direct the CGI light to a forward propagation path extending along the air cavity towards the viewing region. The end reflector is disposed to reflect the CGI light back along a reverse propagation path within the eyepiece frame. The out-coupling PBS is supported at the viewing region to pass the CGI light traveling along the forward propagation path and to redirect the CGI light traveling along the reverse propagation path out of an eye-ward side of the eyepiece frame.

主权项

1. An eyepiece for a head mounted display, the eyepiece comprising:
an eyepiece frame defining an air cavity, the eyepiece frame including an illumination region for receiving computer generated image (“CGI”) light into the eyepiece frame and a viewing region to be aligned with an eye of a user; an in-coupling polarization beam splitter (“PBS”) supported within the eyepiece frame at the illumination region to re-direct the CGI light to a forward propagation path extending along the air cavity towards the viewing region; a reflector disposed at an opposite end of the eyepiece frame from the illumination region to reflect the CGI light back along a reverse propagation path within the eyepiece frame, wherein the reflector comprises a toroidal mirror having multiple radiuses of curvatures; out-coupling PBS supported within the eyepiece frame at the viewing region to pass the CGI light traveling along the forward propagation path and to redirect the CGI light traveling along the reverse propagation path out of an eye-ward side of the eyepiece frame, wherein the out-coupling PBS reflects a substantially orthogonal polarization component of the CGI light than the in-coupling PBS reflects; and a polarization rotator disposed in the forward and reverse propagation paths of the CGI light between the out-coupling PBS and the reflector, wherein the toroidal mirror is disposed in the forward propagation path after the polarization rotator and the out-coupling PBS with the polarization rotator disposed between the toroidal mirror and the out-coupling PBS.