Waveguide combiner system and method with less susceptibility to glare

• US 10,401,620 B1
• Filed: 03/15/2017
• Issued: 09/03/2019
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Rockwell Collins, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Stratton, Eric P., Buchholz, Christopher M., Keith, Christopher A., Stahl, Kurt A., Wilson, Brandon E.
• Primary Examiner(s): Pichler, Marin
• Application Number:
  US15/460,076
• Time in Patent Office: 902 Days
• Field of Search: 359566, 359569, 359572, 359575, 359576, 359 13, 359630, 359632, 359633
• CPC Class Codes: B64D 43/00 Arrangements or adaptations of instruments arrangements of cameras B64D47/08; aeronautical measuring instruments per se G01C
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 2027/0125 Field-of-view increase by wavefront division
• CPC Class Codes: G02B 2027/0145 creating an intermediate image
• CPC Class Codes: G02B 2027/0194 with combiner of laminated type, for optical or mechanical aspects
• CPC Class Codes: G02B 27/0081 with means for altering, e.g. enlarging, the entrance or exit pupil
• 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 27/0149 characterised by mechanical features G02B27/0176 takes precedence
• CPC Class Codes: G02B 27/4205 having a diffractive optical element [DOE] contributing to image formation, e.g. whereby modulation transfer function MTF or optical aberrations are relevant
• CPC Class Codes: G02B 5/18 Diffraction gratings holographic optical elements G02B5/32, G03H; integrally combined with optical fibres G02B6/02057; for coupling light guides G02B6/34; integrally combined with optical integrated light guides G02B6/12; grating systems G02B27/44
• CPC Class Codes: G02B 6/0016 Grooves, prisms, gratings, scattering particles or rough surfaces
• CPC Class Codes: G02B 6/0035 provided on the surface of the light guide or in the bulk of it
• CPC Class Codes: G02F 1/163 Operation of electrochromic cells, e.g. electrodeposition cells; Circuit arrangements therefor

Abstract

A system and method for a head up display (HUD) can mitigate glare. The head up display can include a waveguide combiner including an input grating and an output grating and a glare mitigator disposed to prevent glare through the output grating from reaching an eye box. The glare mitigator can be a shade, a diffuser, a dimming element, or other device for mitigating glare. The glare mitigator can be an active or passive glare mitigator.

Claims

1. A method of providing information to a pilot, the method comprising:

providing light associated with the information from within a glare shield to an input coupler of a substrate waveguide, the input coupler being part of a first portion of the substrate waveguide that is physically coupled with a second portion of the substrate waveguide, the first portion of the substrate waveguide being under and substantially parallel with the glare shield;

providing the light associated with the information at the input coupler of the substrate waveguide into the substrate waveguide by diffraction and diffracting the light associated with the information out of the waveguide at an output coupler of the substrate waveguide for reception by the pilot above the glare shield, wherein the light travels by total internal reflection between the input coupler and the output coupler, the output coupler being part of the second portion of the substrate waveguide, the second portion of the substrate waveguide being angled with respect to the glare shield and the first portion of the substrate waveguide; and

diffusing sunlight before the sunlight strikes on a surface of the substrate waveguide at a location associated with the output coupler to reduce sunspot imaging via diffraction through the output coupler.

2. The method of claim 1 further comprising providing a sensor signal by an ambient sensor to a control circuit, the control circuit causing the sunlight to be dimmed, diffused, or blocked in response to the ambient sensor signal.

3. The method of claim 1, further comprising blocking at least some of the sunlight by an electrometric layer or mechanical device.

4. The method of claim 1, wherein the sunlight is diffused by a layer above the surface of the waveguide.

5. The method of claim 1, wherein the sunlight is diffused by a first diffusive layer and a second diffusive layer, the first diffusive layer attached to a top end of the substrate waveguide and extending approximately parallel to a line of sight of the pilot, the second diffusive layer attached to the substrate waveguide along a surface of the substrate waveguide opposite the output coupler.

6. The method of claim 1, wherein the output coupler includes a diffraction grating and the light from the output coupler is provided to an eye motion box above the glare shield.