Transferable thin-film optical devices

Patent metadata

Field	Value
Publication number	US-10884309-B2
Application number	US-201916274211-A
Country	US
Kind code	B2
Filing date	Feb 12, 2019
Priority date	Aug 8, 2018
Publication date	Jan 5, 2021
Grant date	Jan 5, 2021

Abstract

A transferrable thin-film optical device and a head-mounted display are provided. A transferrable thin-film optical device comprises a thin-film layer providing at least one predetermined optical function. The thin-film layer is configured to be removably attached to a substrate, such that a molecular pattern for the at least one predetermined optical function of the thin-film layer is preserved post removal.

First claim

What is claimed is:

1. A transferrable thin-film optical device, comprising:
a substrate; and
a thin-film liquid crystal layer structurally configured to have liquid crystal molecules aligned in a predetermined alignment pattern to provide at least one predetermined optical function,
wherein the thin-film liquid crystal layer is configured to be removably attached to the substrate, such that the predetermined alignment pattern of the liquid crystal molecules of the thin-film liquid crystal layer is preserved post removal from the substrate, and
wherein the thin-film liquid crystal layer is removably attached to the substrate through a soluble element, which is configured to be dissolved to separate the thin-film liquid crystal layer from the substrate when the thin-film liquid crystal layer is to be transferred to another substrate.

2. The transferrable thin-film optical device according to claim 1 ,
wherein the soluble element is a soluble synthetic polymer layer.

3. The transferrable thin-film optical device according to claim 1 , wherein:
the at least one predetermined optical function of the thin-film liquid crystal layer is provided by in-plane orientations of the liquid crystal molecules configured in the thin-film liquid crystal layer.

4. The transferrable thin-film optical device according to claim 3 , wherein:
the in-plane orientations of the liquid crystal molecules in the thin-film liquid crystal layer are configured by aligned photo-alignment materials.

5. The transferrable thin-film optical device according to claim 3 , wherein:
the thin-film liquid crystal layer is a liquid crystal polymer layer.

6. The transferrable thin-film optical device according to claim 3 , wherein:
the thin-film liquid crystal layer is a bulk photo-alignment material layer that is photo-crosslinked with induced birefringence.

7. The transferrable thin-film optical device according to claim 1 , wherein:
the transferrable thin-film optical device is a Pancharatnam Berry phase element.

8. The transferrable thin-film optical device according to claim 1 , wherein:
the transferrable thin-film optical device is one or more of a transmissive or reflective prism, a lens, a beam deflector, a lens array, a prism array, and a phase retarder.

9. The transferrable thin-film optical device according to claim 1 , wherein:
the thin-film liquid crystal layer includes at least one of nematic liquid crystals, twist-bend liquid crystals, or chiral nematic liquid crystals.

10. The transferrable thin-film optical device according to claim 1 , further comprising:
a plurality of electrodes coupled with the thin-film liquid crystal layer, and configured to provide a driving voltage to the thin-film liquid crystal layer,
wherein the plurality of electrodes include one or more flexible transparent conductive layers, and
wherein the electrodes and the thin-film liquid crystal layer are removable from the substrate as a single entity.

11. The transferrable thin-film optical device according to claim 1 , further comprising:
an adhesive layer,
wherein the thin-film liquid crystal layer has a first surface facing the substrate and an opposing second surface facing away from the substrate, and
wherein the adhesive layer is disposed on the second surface of the thin-film liquid crystal layer.

12. The transferrable thin-film optical device according to claim 11 , wherein:
the adhesive layer is an ultraviolet curable isotropic adhesive layer.

13. The transferrable thin-film optical device according to claim 11 , wherein:
the adhesive layer is an index-matching layer or an index-mismatching layer.

14. An optical system, comprising:
a first optical device; and
a second optical device that is a thin-film optical device attached to a surface of the first optical device, the thin-film optical device providing at least one predetermined optical function and comprising:
a thin-film liquid crystal layer structurally configured to have liquid crystal molecules aligned in a predetermined alignment pattern to provide the at least one predetermined optical function,
wherein the thin-film liquid crystal layer is configured to be removably attached to a substrate prior to being detached from the substrate and attached to the first optical device, wherein the predetermined alignment pattern of the liquid crystal molecules of the thin-film liquid crystal layer is maintained before and after removal from the substrate, and
wherein the thin-film liquid crystal layer is removably attached to the substrate through a soluble element, which is configured to be dissolved to separate the thin-film liquid crystal layer from the substrate when the thin-film liquid crystal layer is transferred to the first optical device.

15. The optical system according to claim 14 , wherein:
the at least one predetermined optical function of the thin-film liquid crystal layer is provided by in-plane orientations of the liquid crystal molecules configured in the thin-film liquid crystal layer.

16. The optical system according to claim 15 , wherein:
the in-plane orientations of the liquid crystal molecules in the thin-film liquid crystal layer are provided by aligned photo-alignment materials.

17. The transferrable thin-film optical device according to claim 1 , further comprising:
an alignment layer disposed between the substrate and the thin-film liquid crystal layer and configured to align the liquid crystal molecules in the predetermined alignment pattern,
wherein the soluble element is disposed between the alignment layer and the substrate, and is configured to be dissolved to separate the thin-film liquid crystal layer and the alignment layer together from the substrate as a single entity.

18. The transferrable thin-film optical device according to claim 17 , wherein a thickness of the thin-film liquid crystal layer is in a range of 0.5 μm to 10 μm, and a thickness of the soluble element is in a range of 0.1 μm to 10 μm.

Assignees

• Facebook Tech Llc

Inventors

• Lu Lu
• Wang Junren
• Mceldowney Scott

Classifications

• G02B27/0093

  with means for monitoring data relating to the user, e.g. head-tracking, eye-tracking · CPC title

• G02B27/0172

  characterised by optical features · CPC title

• G02F1/0322 Primary

  Arrangements comprising two or more independently controlled crystals · CPC title

• G02B27/017

  Head mounted · CPC title

• G02F1/133305

  Flexible substrates, e.g. plastics, organic film · CPC title