HEAD-UP DISPLAY WITH DIFFUSER

• US 20170115627A1
• Filed: 05/13/2015
• Published: 04/27/2017
• Est. Priority Date: 05/16/2014
• Status: Active Grant

• Current Assignee: Envisics Ltd.
• Original Assignee: Two Trees Photonics Limited (DAQRI, LLC)
• Inventors: Christmas, Jamieson, Masiyano, Dackson
• Granted Patent: US 10,585,396 B2
• Time in Patent Office: Days
• CPC Class Codes: G02B 2027/011 comprising device for correcting geometrical aberrations, distortion
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 27/0103 comprising holographic elements
• CPC Class Codes: G02B 5/0263 with positional variation of the diffusing properties, e.g. gradient or patterned diffuser
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/0294 adapted to provide an additional optical effect, e.g. anti-reflection or filter
• CPC Class Codes: G03H 1/0841 Encoding method mapping the synthesized field into a restricted set of values representative of the modulator parameters, e.g. detour phase coding
• CPC Class Codes: G03H 1/16 using Fourier transform G03H1/10, G03H1/12, G03H1/14 take precedence; analogue computers G06G, e.g. G06G7/19
• CPC Class Codes: G03H 1/2205 using downstream optical component
• CPC Class Codes: G03H 1/2294 Addressing the hologram to an active spatial light modulator
• CPC Class Codes: G03H 2001/085 Kinoform, i.e. phase only encoding wherein the computed field is processed into a distribution of phase differences
• CPC Class Codes: G03H 2001/221 Element having optical power, e.g. field lens
• CPC Class Codes: G03H 2001/2221 Screen having complex surface, e.g. a structured object
• CPC Class Codes: G03H 2223/14 Diffuser, e.g. lens array, random phase mask
• CPC Class Codes: G03H 2223/17 Element having optical power
• CPC Class Codes: G03H 2223/24 Reflector; Mirror
• CPC Class Codes: G03H 2225/32 Phase only

Abstract

There is provided a head-up display for a windscreen having spatially variant optical power. The head-up display comprises a diffuser arranged to display an image. The diffuser is shaped to compensate for the spatially variant optical power of the windscreen. A holographic projector may be provided, which is arranged to project the image for display onto the diffuser; the holographic projector comprises a spatial light modulator arranged to apply a phase-delay distribution to incident light, wherein the phase-delay distribution comprises phase-only data representative of an object; the projector further comprises Fourier transform means arranged to perform a Fourier transform of phase modulated light received from the spatial light modulator and to form the image on the diffuser.

Claims

1-12. -12. (canceled)

13. A head-up display for a windscreen having spatially variant optical power, the head-up display comprising:

a diffuser arranged to display an image, wherein the diffuser is shaped to compensate for the spatially variant optical power of the windscreen; and

a holographic projector configured to project the image for display onto the diffuser, the holographic projector comprising;

a spatial light modulator arranged to apply a phase-delay distribution to incident light, wherein the phase-delay distribution comprises phase-only data representative of an object and is arranged to bring the image to a non-planar focus; and

Fourier transform means arranged to perform a Fourier transform of phase modulated light received from the spatial light modulator and form the image on the diffuser.

14. The head-up display of claim 13, further comprising a mirror arranged to receive light from the diffuser and redirect the received light onto the windscreen.

15. The head-up display of claim 14, wherein the mirror has optical power.

16. The head-up display of claim 13, wherein the windscreen forms part of an optical system arranged to form a virtual image of the image displayed by the diffuser.

17. The head-up display of claim 13, further comprising a laser arranged to produce the incident light for the spatial light modulator.

18. A method of manufacturing the head-up display of claim 13, the method comprising:

shaping the diffuser to compensate for the spatially variant optical power of the windscreen.

19. A method of displaying an image on a windscreen for a head-up display, the windscreen having spatially variant optical power, the method comprising:

displaying an image on a diffuser by projecting the image onto the diffuser, wherein the diffuser is shaped to compensate for the spatially variant optical power of the windscreen and projecting the image onto the diffuser comprises;

illuminating a spatial light modulator with incident light to apply a phase-delay distribution to the incident light, wherein the phase-delay distribution comprises phase-only data representative of an object; and

performing a Fourier transform of the phase modulated light received from the spatial light modulator and forming the image on the diffuser; and

forming a virtual image of the image using an optical system comprising the windscreen.