WAVEGUIDES WITH INTEGRATED OPTICAL ELEMENTS AND METHODS OF MAKING THE SAME
This disclosure describes optical devices, such as waveguides, and methods of manufacturing same. An example waveguide can include a polymer layer having substantially optically transparent material with first and second major surfaces configured such that light containing image information can propagate through the polymer layer being guided therein by reflecting from the first and second major surfaces via total internal reflection. The first surface can include first smaller and second larger surface portions monolithically integrated with the polymer layer and with each other. The first smaller surface portion can include at least a part of an in-coupling optical element configured to couple light incident on the in-coupling optical element into the polymer layer for propagation therethrough by reflection from the second major surface and the second larger surface portion of the first major surface.
1 . A method of making a waveguide, the method comprising:
providing first and second molds, the first mold and the second mold facing one another, wherein at least the first mold comprises an imprint of at least a part of at least one in-coupling optical element:
providing a polymer material between the first and second molds:
contacting the polymer material with the first and second molds such that the first mold transfers a corresponding imprint of the at least a part of the at least one in-coupling optical element into the polymer material:
exposing the polymer material to a hardening process: and
removing the polymer material from the first and second molds to provide the waveguide that includes the at least a part of the at least one in-coupling optical element.
2 . The method of claim 1 , wherein exposing the polymer material to a hardening process comprises exposing the polymer material to ultraviolet light.
3 . The method of claim 1 , wherein the waveguide comprises a plurality of surfaces configured to guide light containing image information in the waveguide by total internal reflection.
4 . The method of claim 3 , wherein at least one of the plurality of surfaces has a surface roughness between about 0.1 nm to about 2.0 nm.
5 . The method of claim 1 , wherein the at least one in-coupling optical element comprises a tilted surface.
6 . The method of claim 5 , wherein the tilted surface has curvature.
7 . The method of claim 1 , wherein the at least one in-coupling optical element comprises at least one grating.
8 . The method of claim 1 , wherein the at least one in-coupling optical element comprises at least one lens that is arranged to impart optical power to the light that is received by the at least one in-coupling optical element.
9 . The method of claim 8 , wherein the at least one lens is formed in at least one surface of the waveguide and is monolithically integrated with the waveguide.
10 . The method of claim 9 , wherein the at least one in-coupling optical element further comprises at least one grating, and wherein the at least one grating is aligned with the at least one lens such that the at least one lens is arranged to impart optical power to the light that is received by the at least one grating.
11 . The method of claim 1 , wherein the at least one in-coupling optical element includes a prism.
12 . The method of claim 1 , wherein the at least a part of the at least one in-coupling optical element is monolithically integrated with the waveguide.
13 . The method of claim 1 , wherein:
at least the first mold further comprises an imprint of at least a part of at least one anti-reflective structure;
the first mold further transfers a corresponding imprint of the at least a part of the at least one anti-reflective structure into the polymer material; and
removing the polymer material from the first and second molds provides the waveguide that further includes the at least a part of the at least one anti-reflective structure.
14 . The method of claim 13 , wherein the at least one anti-reflective structure is separate from the at least one in-coupling optical element.
15 . The method of claim 13 , wherein the at least a part of the at least one anti-reflective structure is monolithically integrated with the waveguide.
16 . The method of claim 13 , wherein the at least one anti-reflective structure comprises at least one of an undulating pattern and a periodic pattern.