US 12,306,404 B2
Waveguide-type display device
Jeonggeun Yun, Suwon-si (KR); Byoungho Lee, Seoul (KR); Kiseung Bang, Seoul (KR); Chanhyung Yoo, Seoul (KR); Kyookeun Lee, Suwon-si (KR); and Minseok Chae, Seoul (KR)
Assigned to SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR); and SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION, Seoul (KR)
Filed by SAMSUNG ELECTRONICS CO., LTD., Suwon-si (KR); and SEOUL NATIONAL UNIVERSITY R&DB FOUNDATION, Seoul (KR)
Filed on Aug. 2, 2022, as Appl. No. 17/879,469.
Application 17/879,469 is a continuation of application No. PCT/KR2021/000735, filed on Jan. 19, 2021.
Claims priority of application No. 10-2020-0030378 (KR), filed on Mar. 11, 2020.
Prior Publication US 2022/0390749 A1, Dec. 8, 2022
Int. Cl. G02B 27/01 (2006.01); F21V 8/00 (2006.01); G02B 27/00 (2006.01); G02B 27/28 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 6/0056 (2013.01); G02B 27/0081 (2013.01); G02B 27/283 (2013.01); G02B 2027/0118 (2013.01); G02B 2027/0123 (2013.01); G02B 2027/0134 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A waveguide-type display device comprising:
a waveguide;
an input coupler provided on the waveguide and configured to transmit an image to travel into the waveguide;
an output coupler provided on the waveguide and configured to output the image traveling in the waveguide to an outside of the waveguide;
a field-of-view (FOV) expander configured to output an image having an expanded FOV by deflecting and outputting the image output from the output coupler in a certain direction based on polarization characteristics of the image, the FOV expander comprising:
a first ¼ wave plate configured to convert the image output from the output coupler into an image of circular polarization; and
a first polarization grating configured to deflect and output the image of the circular polarization, output from the first ¼ wave plate, in a direction that is different from a direction of the image output from the first ¼ wave plate, based on a rotational direction of the circular polarization;
an external light compensator configured to deflect external light corresponding to an external environment, the external light compensator comprising:
a circular polarizer configured to output a portion of the external light as external light of circular polarization;
a second polarization grating configured to deflect and output the external light of the circular polarization, output from the circular polarizer; and
a second ¼ wave plate configured to convert the external light of the circular polarization, output from the second polarization grating, into external light of linear polarization and pass the external light of linear polarization through the waveguide to the FOV expander;
a first spacer between the waveguide and the FOV expander; and
a second spacer between the output coupler and the external light compensator;
wherein the circular polarizer, the second polarization grating, and the second ¼ wave plate, the second spacer, the waveguide, the first spacer, the first ¼ wave plate and the first polarization grating are arranged sequentially in a direction perpendicular to a longitudinal direction of the waveguide.