Optical arrangements including Fresnel lens elements

Patent metadata

Field	Value
Publication number	US-11693238-B2
Application number	US-202016921112-A
Country	US
Kind code	B2
Filing date	Jul 6, 2020
Priority date	Mar 21, 2016
Publication date	Jul 4, 2023
Grant date	Jul 4, 2023

Abstract

An optical lens arrangement comprises a first Fresnel lens element and a second lens element. The first Fresnel lens element defines a flat surface side and an opposite faceted surface side defining wedge and draft faces. The flat surface side faces towards the eye of a user and the opposite faceted surface side faces away from the eye of the user. The second lens element interfaces with the faceted surface side of first Fresnel lens. The second lens element is selected from the group consisting of: a second Fresnel lens element, a singlet lens element, a doublet lens element and any combination thereof. The first Fresnel lens is proximal relative to the eye of the user and the second lens element is distal relative to the eye of the user. Head mounted devices (HMD) including these optical lens arrangements are provided. Methods of making such optical lens arrangements and HMDs are also provided.

First claim

What is claimed is:

1. An optical lens arrangement in a head-mounted device including an opaque display screen comprising:
a first Fresnel lens element defining a flat surface side and an opposite faceted surface side defining wedge faces and draft faces, the flat surface side facing towards the opaque display screen and away from an eye of a user while the head-mounted device is worn and the faceted surface side facing away from the opaque display screen and towards the eye of the user while the head-mounted device is worn; and
a second Fresnel lens element defining a flat surface side and an opposite faceted surface side defining wedge faces and draft faces, the faceted surface side of the second Fresnel lens element facing towards the faceted surface side of first Fresnel lens and the flat surface side of the second Fresnel lens element facing away from the first Fresnel lens element.

2. The optical lens arrangement of claim 1 , wherein at least one of the draft faces of the first Fresnel lens element or the draft faces of the second Fresnel lens element comprise a black absorbing coating or dye.

3. The optical lens arrangement of claim 1 , wherein at least one of the draft faces of the first Fresnel lens element or the draft faces of the second Fresnel lens element comprise a rough diffusive finish.

4. The optical lens arrangement of claim 1 , wherein at least one of the draft faces of the first Fresnel lens element or the draft faces of the second Fresnel lens element comprise an anti-reflective coating.

5. The optical lens arrangement of claim 1 , wherein the optical lens arrangement defines an optical axis, a draft angle being defined between the draft faces of the first Fresnel lens element and the optical axis of the optical lens arrangement in a plane in which the optical axis lies, wherein the draft angles are arranged for providing for light rays passing through the optical lens arrangement to be almost substantially parallel to the draft faces of the first Fresnel lens element for a specific pupil position.

6. The optical lens arrangement of claim 1 , wherein at least one of the flat surface side of the first Fresnel lens element or the flat surface side of the second Fresnel lens element comprises a diffractive surface.

7. The optical lens arrangement of claim 6 , wherein the diffractive surface comprises a binary surface.

8. The optical lens arrangement of claim 1 , further comprising a third lens element interposed between the first Fresnel lens element and the second Fresnel lens element.

9. The optical lens arrangement of claim 1 , comprising a binary surface adjacent to a space between the first Fresnel lens element and the second Fresnel lens element.

10. The optical lens arrangement of claim 1 , wherein a distance between the first Fresnel lens element and the second Fresnel lens element is from about 0 mm to about 5 mm.

11. A head-mounted device comprising:
a data image processor;
an opaque display screen in communication with the data image processor to display an image; and
an optical lens arrangement comprising:
a first Fresnel lens element defining a flat surface side and an opposite faceted surface side defining wedge faces and draft faces, the flat surface side facing away from the opaque display screen and away from an eye of a user while the head-mounted device is worn and the faceted surface side facing towards the opaque display screen and towards the eye of the user while the head-mounted device is worn; and
a second Fresnel lens element defining a flat surface side and an opposite faceted surface side defining wedge faces and draft faces, the faceted surface side of the second Fresnel lens element facing towards the faceted surface side of first Fresnel lens and the flat surface side of the second Fresnel lens element facing away from the first Fresnel lens element.

12. The head-mounted device of claim 11 , wherein at least one of the draft faces of the first Fresnel lens element or the draft faces of the second Fresnel lens comprise at least one of a black absorbing coating or dye, a rough diffusive finish, or an anti-reflective coating.

13. The head-mounted device of claim 11 , wherein the optical lens arrangement defines an optical axis, a draft angle being defined between the draft faces of the first Fresnel lens element and the optical axis of the optical lens arrangement in a plane in which the optical axis lies, wherein the draft angles are arranged for providing for light rays passing through the optical lens arrangement to be almost substantially parallel to the draft faces of the first Fresnel lens element for a specific pupil position.

14. The head-mounted device of claim 11 , wherein the optical lens arrangement further comprises a third lens element interposed between the first Fresnel lens element and the second Fresnel lens element.

15. The head-mounted device of claim 11 , wherein the optical lens arrangement comprises a binary surface adjacent to a space between the first Fresnel lens element and the second Fresnel lens element.

16. The head-mounted device of claim 11 , wherein a distance between the first Fresnel lens element and the second Fresnel lens element is from about 0 trim to about 5 mm.

17. The head-mounted device of claim 11 , wherein the image is a video image.

18. The head-mounted device of claim 11 , wherein the image is a virtual reality image.

19. The head-mounted device of claim 11 , wherein the image is an augmented reality image.

20. A method of making a lens arrangement in a head-mounted device including an opaque display screen comprising:
providing a first Fresnel lens element defining a flat surface side and an opposite faceted surface side defining wedge and draft faces, the flat surface side being positioned for facing towards the opaque display screen and away from an eye of a user while the head-mounted device is worn and the faceted surface side being positioned for facing away from the opaque display screen and towards the eye of the user while the head-mounted device is worn; and
positioning a second Fresnel lens element proximate to first Fresnel element, the second Fresnel lens element defining a flat surface side and an opposite faceted surface side defining wedge faces and draft faces, the faceted surface side of the second Fresnel lens element facing towards the faceted surface side of first Fresnel lens and the flat surface side of the second Fresnel lens element facing away from the first Fresnel lens element.

Assignees

• Apple Inc

Inventors

• Fortin-Deschenes Simon
• Powell Ian

Classifications

• G02B25/001

  Eyepieces · CPC title

• G02B25/008 Primary

  comprising two or more lenses (G02B25/004 - G02B25/007 take precedence) · CPC title

• G02B3/08 Primary

  with discontinuous faces, e.g. Fresnel lens {(diffractive Fresnel lenses G02B5/1876)} · CPC title

• G02B2027/0118

  comprising devices for improving the contrast of the display / brillance control visibility · CPC title

• G02B27/0018

  with means for preventing ghost images (anti-reflection coatings G02B1/11) · CPC title