US 12,352,974 B2
Optical system for directing an image for viewing
Yochay Danziger, Kfar Vradim (IL)
Assigned to Lumus Ltd., Ness Ziona (IL)
Filed by Lumus Ltd., Ness Ziona (IL)
Filed on Jan. 8, 2023, as Appl. No. 18/094,362.
Application 18/094,362 is a continuation in part of application No. PCT/IL2022/050216, filed on Feb. 24, 2022.
Claims priority of provisional application 63/430,036, filed on Dec. 4, 2022.
Claims priority of provisional application 63/424,923, filed on Nov. 13, 2022.
Claims priority of provisional application 63/421,769, filed on Nov. 2, 2022.
Claims priority of provisional application 63/324,218, filed on Mar. 28, 2022.
Claims priority of provisional application 63/297,299, filed on Jan. 7, 2022.
Prior Publication US 2023/0221561 A1, Jul. 13, 2023
Int. Cl. G02B 27/01 (2006.01); F21V 8/00 (2006.01)
CPC G02B 27/0172 (2013.01) [G02B 6/0035 (2013.01); G02B 6/005 (2013.01); G02B 2027/0178 (2013.01)] 18 Claims
OG exemplary drawing
 
1. An optical system for directing light beams corresponding to an image from an image projector towards a user for viewing, the optical system comprising:
(a) a partial-internal-reflection rectangular light guide (PRLG) formed from a transparent material and having first and second mutually-parallel major surfaces, a third major surface perpendicular to said first and second major surfaces, said first, second and third major surfaces supporting internal reflection for a range of incident angles, and a fourth major surface parallel to said third major surface, at least part of said fourth major surface provided with a non-diffractive, partially-reflecting coating;
(b) a second light guide portion having a pair of mutually-parallel major surfaces for conveying the light beams by internal reflection, said second light guide portion optically coupled to at least part of an area of said partially-reflecting coating, said second light guide portion containing a set of planar, mutually-parallel, partially-reflecting surfaces located between, and non-parallel to, said pair of major surfaces;
(c) a third light guide portion, formed as a continuation of, or adjacent to, said second light guide portion, said third light guide portion including a coupling-out configuration deployed for coupling-out the light beams propagating within the third light guide portion by internal reflection so as to direct the light beams towards the user; and
(d) a coupling-in arrangement for coupling light beams corresponding to a collimated image from the image projector into said PRLG so as to propagate within said PRLG by four-fold internal reflection at said first, second, third and fourth major surfaces,
such that the light beams from the image projector propagating by four-fold internal reflection within said PRLG are progressively emitted from said PRLG through said partially-reflecting coating and enter said second light guide portion, are redirected by reflection at said set of partially-reflecting surfaces so as to propagate within said third light guide portion, and are coupled-out from said third light guide portion by said coupling-out configuration towards the user.