EP-4740050-A1 - TAPERED ANTI-REFLECTION COATING THAT PRESERVES IMAGE SHARPNESS IN WAVEGUIDE COMBINERS

Abstract

Embodiments of the disclosure provided herein include waveguide combiners. More specifically, embodiments described herein provide for waveguide combiners with a waveguide layer and a coating having a tapered portion disposed thereover. The waveguide includes one or more gratings, the one or more gratings including a plurality of grating structures disposed over a waveguide substrate, wherein the grating structures include a waveguide material, and the plurality of grating structures include exterior grating structures at outer edges of the one or more gratings. A waveguide layer is disposed over the waveguide substrate between the exterior grating structures and an edge of the waveguide substrate, the waveguide layer including the waveguide material, and a coating disposed over the waveguide layer, the coating having a tapered portion that is tapered from at least one of the exterior grating structures to a planar portion of the coating.

Inventors

• SHASTRI, Kunal
• Wang, Evan
• LORENZO, Simon
• SELL, DAVID ALEXANDER
• MESSER, Kevin
• BHARGAVA, SAMARTH

Assignees

• Applied Materials, Inc.

Dates

Publication Date

20260513

Application Date

20240618

Claims (20)

1. 1. A waveguide, comprising: one or more gratings, the one or more gratings comprising a plurality of grating structures disposed over a waveguide substrate, wherein: the grating structures comprise a waveguide material, and the plurality of grating structures comprise exterior grating structures at outer edges of the one or more gratings; a waveguide layer disposed over the waveguide substrate between the exterior grating structures and an edge of the waveguide substrate, the waveguide layer including the waveguide material; and a coating disposed over the waveguide layer, the coating having a tapered portion that is tapered from at least one of the exterior grating structures to a planar portion of the coating.
2. 2. The waveguide of claim 1 , wherein the coating is disposed over the waveguide substrate between the exterior grating structures and the edge of the waveguide substrate.
3. 3. The waveguide of claim 1 , wherein the one or more gratings are one of an input coupling region, an intermediate region, or an output coupling region.
4. 4. The waveguide of claim 1 , wherein the waveguide layer and the grating structures have the same thickness.
5. 5. The waveguide of claim 1 , wherein the coating has a refractive index of less than 2.0.
6. 6. The waveguide of claim 1 , wherein the coating comprises a coating refractive index and the waveguide layer comprises a waveguide layer refractive index, the coating refractive index is less than the waveguide layer refractive index.
7. 7. The waveguide of claim 1 , wherein of the coating includes a planar portion adjacent to an outer taper edge of the tapered portion.
8. 8. A waveguide, comprising: one or more gratings comprising a plurality of grating structures disposed over a waveguide substrate, the plurality of grating structures comprising a waveguide and comprising exterior grating structures at outer edges of the one or more gratings; a waveguide layer having the waveguide material and disposed over the waveguide substrate between the exterior grating structures and an edge of the waveguide substrate; and a coating disposed over the waveguide layer, the coating having a coating refractive index less than the waveguide layer refractive index and having a tapered portion that is tapered from at least one of the exterior grating structures to a planar portion of the coating adjacent to an outer taper edge of the tapered portion.
9. 9. The waveguide of claim 8, wherein the one or more gratings are one of an input coupling region, an intermediate region, or an output coupling region.
10. 10. The waveguide of claim 8, wherein the coating has a thickness of between about 10 nanometers to about 800 nanometers.
11. 11 . The waveguide of claim 8, wherein the coating refractive index is less than 2.0.
12. 12. The waveguide of claim 8, wherein the waveguide layer and the grating structures have the same thickness.
13. 13. The waveguide of claim 8, wherein a distance between the inner taper edge and an outer taper edge of the coating is from about 1 micrometer to about 2000 micrometers.
14. 14. A waveguide, comprising: one or more gratings comprising a plurality of grating structures disposed over a waveguide substrate, the plurality of grating structures comprise a waveguide material and exterior grating structures at outer edges of the one or more gratings; a waveguide layer disposed over the waveguide substrate between the exterior grating structures and an edge of the waveguide substrate, the waveguide layer including the waveguide material and having the same thickness as the plurality of grating structures; and a coating disposed over the waveguide layer, the coating having a tapered portion that is tapered from at least one of the exterior grating structures to a planar portion of the coating.
15. 15. The waveguide of claim 14, wherein the one or more gratings are one of an input coupling region, an intermediate region, or an output coupling region.
16. 16. The waveguide of claim 14, wherein the coating comprises a coating refractive index and the waveguide layer comprises a waveguide layer refractive index, the coating refractive index is less than the waveguide layer refractive index.
17. 17. The waveguide of claim 16, wherein the coating refractive index is less than 2.0.
18. 18. The waveguide of claim 14, wherein the coating has a thickness of between about 10 nanometers to about 800 nanometers.
19. 19. The waveguide of claim 14, wherein the tapered portion comprises an outer taper edge adjacent to the planar portion of the coating and an inner taper edge adjacent to the exterior grating structures.
20. 20. The waveguide of claim 20, wherein a distance between the inner taper edge and an outer taper edge of the coating is from about 1 micrometer to about 2000 micrometers.

Description

TAPERED ANTI-REFLECTION COATING THAT PRESERVES IMAGE SHARPNESS IN WAVEGUIDE COMBINERS BACKGROUND Field [0001] Embodiments of the present disclosure generally relate to waveguide combiners. More specifically, embodiments described herein provide for waveguide combiners with a waveguide layer and a coating having a tapered portion disposed thereover. Description of the Related Art [0002] Virtual reality is generally considered to be a computer generated simulated environment in which a user has an apparent physical presence. A virtual reality experience can be three-dimensionally generated and viewed with a head-mounted display (HMD), such as glasses or other wearable display devices that have near-eye display panels as lenses to display a virtual reality environment that replaces an actual environment. [0003] Augmented reality, however, enables an experience in which a user can still see through the display lenses of the glasses or other HMD device to view the surrounding environment, yet also see images of virtual objects that are generated for display and appear as part of the environment. Augmented reality can include any type of input, such as audio and haptic inputs, as well as virtual images, graphics, and video that enhance or augment the environment that the user experiences. Image sharpness of the virtual image may be affected by the environment. [0004] Accordingly, there is a need for waveguide combiners with a waveguide layer and a coating having a tapered portion disposed thereover. SUMMARY [0005] Embodiments described herein generally relate to systems and methods used for waveguide combiners. More specifically, embodiments described herein provide for waveguide combiners with a waveguide layer and a coating having a tapered portion disposed thereover. [0006] In an embodiment, a waveguide is provided. The waveguide includes one or more gratings, the one or more gratings including a plurality of grating structures disposed over a waveguide substrate, wherein the grating structures include a waveguide material, and the plurality of grating structures include exterior grating structures at outer edges of the one or more gratings. A waveguide layer is disposed over the waveguide substrate between the exterior grating structures and an edge of the waveguide substrate, the waveguide layer including the waveguide material, and a coating disposed over the waveguide layer, the coating having a tapered portion that is tapered from at least one of the exterior grating structures to a planar portion of the coating. [0007] In another embodiment, a waveguide is provided. The waveguide includes one or more gratings including a plurality of grating structures disposed over a waveguide substrate, the plurality of grating structures including exterior grating structures at outer edges of the one or more gratings, a waveguide layer disposed over the waveguide substrate between the exterior grating structures and an edge of the waveguide substrate, and a coating disposed over the waveguide layer, the coating having a tapered portion that is tapered from at least one of the exterior grating structures to a planar portion of the coating adjacent to an outer taper edge of the tapered portion. [0008] In yet another embodiment, a waveguide is provided. The waveguide includes one or more gratings including a plurality of grating structures disposed over a waveguide substrate. The plurality of grating structures include a waveguide material and exterior grating structures at outer edges of the one or more gratings. The waveguide also includes a waveguide layer disposed over the waveguide substrate between the exterior grating structures and an edge of the waveguide substrate, and a coating disposed over the waveguide layer, the coating having a tapered portion that is tapered from at least one of the exterior grating structures to a planar portion of the coating. The waveguide layer includes the waveguide material and having the same thickness as the plurality of grating structures. BRIEF DESCRIPTION OF THE DRAWINGS [0009] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only exemplary embodiments of the present disclosure and are therefore not to be considered limiting of its scope, and may admit to other equally effective embodiments of the present disclosure. [0010] Figure 1A illustrates a schematic top view of a waveguide combiner, according to certain embodiments. [0011] Figure 1 B illustrates a schematic cross-sectional view of a portion of the waveguide combiner of Figure 1 A, according to certain embodiments. [0012] To facilitate understanding, identical reference numerals have been used, where possible, to designate