Multi-plane display device

Patent metadata

Field	Value
Publication number	US-12468152-B2
Application number	US-202117787936-A
Country	US
Kind code	B2
Filing date	Mar 29, 2021
Priority date	Apr 1, 2020
Publication date	Nov 11, 2025
Grant date	Nov 11, 2025

Abstract

A head-up display is described. A spatial light modulator is arranged to display a diffractive pattern of first picture content and/or second picture content. A screen assembly has first and second diffusers arranged in a stepped configuration so that the first diffuser is spatially offset from the second diffuser by a perpendicular distance. A light source is arranged to illuminate the diffractive pattern such that the first picture content is formed on the first diffuser and/or the second picture content is formed on the second diffuser. An optical system comprising at least one optical element having optical power is arranged so that the first and second diffusers have different object distances to the optical system.

First claim

The invention claimed is:

1 . A head-up display comprising:
a spatial light modulator configured to display a diffractive pattern encoding first picture content and second picture content, wherein the diffractive pattern comprises (i) a first component comprising a first Fourier hologram of the first picture content and a first lensing function and (ii) a second component comprising a second Fourier hologram of the second picture content and a second lensing function that is the same as the first lensing function; a screen assembly comprising a first diffuser and a second diffuser, wherein the first diffuser and the second diffuser are arranged in a stepped configuration so that the first diffuser is spatially offset from the second diffuser by a perpendicular distance; a light source configured to illuminate the diffractive pattern such that the first picture content is formed on the first diffuser and the second picture content is formed on the second diffuser; and an optical system comprising at least one optical element having optical power, wherein the first and second diffusers have different object distances to the at least one optical element of the optical system.

2 . The head-up display according to claim 1 wherein, in operation, the at least one optical element is configured to relay the first picture content formed on the first diffuser or the second picture content formed on the second diffuser along a common light propagation path along a propagation axis towards an optical combiner for forming respective virtual images at different virtual image distances from a viewing plane.

3 . The head-up display according to claim 1 , wherein an optical element is arranged along at least one of a first light propagation path between the spatial light modulator and the first diffuser and a second light propagation path between the spatial light modulator and the second diffuser such that the first light propagation path has the same length along its propagation axis as the second light propagation path.

4 . The head-up display according to claim 3 , further comprising:
a first optical element arranged along a propagation axis of the first light propagation path between the spatial light modulator and the first diffuser, the first optical element arranged to fold the first light propagation path; and a second optical element arranged along a propagation axis of the second light propagation path between the spatial light modulator and the second diffuser, the second optical element arranged to fold the second light propagation path, wherein the first optical element and the second optical element are spatially separated so that the first light propagation path has the same length along its propagation axis as the second light propagation path.

5 . The head-up display according to claim 3 , wherein the optical element is arranged along at least one of the first light propagation path between the spatial light modulator and the first diffuser and the second light propagation path between the spatial light modulator and the second diffuser, wherein the at least one optical element is arranged to adjust the optical path length such that the first light propagation path has the same length along its propagation axis as the second light propagation path.

6 . The head-up display according to claim 5 , wherein the optical element comprises a refractive optical element arranged to adjust an optical path length of light propagating therethrough.

7 . The head-up display according to claim 1 wherein the screen assembly is arranged orthogonal to the spatial light modulator and wherein the perpendicular distance from the spatial light modulator to the first diffuser is different to the perpendicular distance from the spatial light modulator to the second diffuser.

8 . The head-up display according to claim 1 wherein the first picture content and the second picture content are formed on the screen assembly at the same time.

9 . The head-up display according to claim 1 wherein the first picture content and the second picture content are formed at different times within an integration time of a human eye in accordance with a time multiplexing scheme.

10 . The head-up display according to claim 1 wherein the first diffuser and the second diffuser of the screen assembly are integrally formed.

11 . The head-up display according to claim 10 , wherein the screen assembly comprises one of (i) a stepped disc or (ii) a rotatable disc.

12 . The head-up display according to claim 1 , wherein the diffractive pattern comprises a Fresnel hologram of the first picture content and the second picture content.

13 . A screen assembly configured for use in a head-up display system configured to generate holographic reconstructions using a spatial light modulator arranged to display a diffractive pattern encoding first picture content and second picture content, wherein the diffractive pattern comprises (i) a first component comprising a first Fourier hologram of the first picture content and a first lensing function and (ii) a second component comprising a second Fourier hologram of the second picture content and a second lensing function that is the same as the first lensing function, wherein the screen assembly comprises:
a first diffuser and a second diffuser arranged in a stepped configuration so that the first diffuser is spatially offset from the second diffuser by a perpendicular distance; wherein the first diffuser is configured to receive and display a first holographic reconstruction of the first picture content formed by illuminating the first component of the diffractive pattern comprising the first Fourier hologram and the first lensing function; wherein the second diffuser is configured to receive and display a second holographic reconstruction of the second picture content formed by illuminating the second component of the diffractive pattern comprising the second Fourier hologram and the second lensing function that is the same as the first lensing function; and wherein the first and second diffusers have different object distances relative to an optical system having optical power for forming respective virtual images at different virtual image distances from a viewing plane.

14 . A vehicle comprising a head-up display, wherein the head-up display comprises:
a spatial light modulator configured to display a diffractive pattern encoding first picture content and second picture content, wherein the diffractive pattern comprises (i) a first component comprising a first Fourier hologram of the first picture content and a first lensing function and (ii) a second component comprising a second Fourier hologram of the second picture content and a second lensing function that is the same as the first lensing function; a screen assembly comprising a first diffuser and a second diffuser, wherein the first diffuser and the second diffuser are arranged in a stepped configuration so that the first diffuser is spatially offset from the second diffuser by a perpendicular distance; a light source configured to illuminate the diffractive pattern such that the first picture content is formed on the first diffuser and the second picture content is formed on the second diffuser; and an optical system comprising at least one optical element having optical power, wherein the first and second diffusers have different object distances to the at least one optical element of the optical system.

15 . The vehicle of claim 14 , wherein in operation, the at least one optical element is configured to relay the first picture conten

Assignees

• Envisics Ltd
• Enviscis Ltd

Inventors

• Christmas Jamieson
• Karner Máté
• Cole Alexander
• Chowdhury Sahar

Classifications

• B60K35/211

  producing three-dimensional [3D] effects, e.g. stereoscopic images · CPC title

• B60K35/232

  controlling the projection distance of virtual images depending on the condition of the vehicle or the driver · CPC title

• B60K35/85

  Arrangements for transferring vehicle- or driver-related data · CPC title

• B60K35/10

  Input arrangements, i.e. from user to vehicle, associated with vehicle functions or specially adapted therefor · CPC title

• B60K2360/29

  Holographic features · CPC title