HUD system and method with dynamic light exclusion

• US 9,679,367 B1
• Filed: 04/24/2014
• Issued: 06/13/2017
• Est. Priority Date: 04/17/2013
• 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: Wald, Daniel S., Wilson, Brandon E., Stratton, Eric P., Kelly, Conor D.
• Primary Examiner(s): Zimmerman, Mark
• Assistant Examiner(s): Tswei, Yu-Jang
• Application Number:
  US14/260,943
• Time in Patent Office: 1,146 Days
• Field of Search: None
• CPC Class Codes: B60K 2360/20 Optical features of instruments
• CPC Class Codes: B60K 2360/21 using cameras
• CPC Class Codes: B60K 2360/25 using filters
• CPC Class Codes: B60K 2360/693 Cover plate features
• CPC Class Codes: B60K 35/00 Instruments specially adapted for vehicles; Arrangement of instruments in or on vehicles
• CPC Class Codes: G02B 2027/0118 comprising devices for improving the contrast of the display / brillance control visibility
• CPC Class Codes: G02B 27/01 Head-up displays
• CPC Class Codes: G02B 27/0101 characterised by optical features G02B27/0172 takes precedence
• CPC Class Codes: G02B 5/23 Photochromic filters
• CPC Class Codes: G06T 5/20 using local operators
• CPC Class Codes: G06T 5/94 based on local image properties, e.g. for local contrast enhancement
• CPC Class Codes: H04N 23/63 by using electronic viewfinders
• CPC Class Codes: H04N 23/951 by using two or more images to influence resolution, frame rate or aspect ratio

Abstract

A system and method can mitigate or prevent contrast ratio issues due to bright light (e.g., light saturation) in a head up display (HUD). The head up display can include a waveguide combiner (or non-waveguide combiner) and a mitigator disposed to prevent or reduce bright light from being provided through the combiner. The bright light can be direct lunar light, direct solar light, or solar/lunar reflections. The mitigator dynamically selects and reduces bright background light which results in an increase of contrast ratio.

Claims

1. A head up display for use in a cockpit environment for providing light from an image source, the head up display comprising:

a sensor array;

a combiner configured to allow viewing of an outside scene and information from the image source, wherein the combiner comprises a waveguide have an input and an output, the light associated with the information traveling from the input to the output by total internal reflection within the waveguide, wherein bright light from the cockpit environment is virtually provided through the waveguide into an eye box at a virtual location;

a processing circuit configured to determine the virtual location in response to data from the sensor array and provide a control signal; and

a dynamic gradient disposed to selectably reduce or prevent transmission through the combiner of the bright light from the cockpit environment observed by the sensor array in response to the control signal, the dynamic gradient utilizing at least one selectably opaque area to reduce or prevent transmission of the bright light through the combiner, the at least one selectably opaque area corresponding to the virtual location of the bright light on the combiner, and wherein the at least one selectably opaque area is shaped to a correspond to a shape of the bright location at the virtual location on the combiner.

2. The head up display of claim 1, wherein the dynamic gradient comprises a dynamic filter.

3. The head up display of claim 1, wherein the dynamic gradient is disposed on a side of the combiner closer to a windshield than another side of the combiner.

4. The head up display of claim 1, wherein the combiner comprises at least one diffractive element coupler.

5. The head up display of claim 4, wherein the dynamic gradient covers an area associated with the diffractive element coupler.

6. The head up display of claim 1, wherein the dynamic gradient creates an exclusion area on a pixel-by-pixel basis.

7. The head up display of claim 1, further comprising an eye sensor.

8. The head up display of claim 7, wherein the processing circuit is configured to receive aircraft position, velocity and acceleration parameters and correlate a first position of a user eye, and a second position of a bright light on the sensor array and uses the first and second position to select a location to reduce or prevent transmission of the bright light on the dynamic gradient.

9. The head up display of claim 1, wherein the dynamic gradient comprises a liquid crystal material, organic light emitting diode material, or dynamic neutral density filter.

10. The head up display of claim 1, wherein the processing circuit is configured to determine a future position of the bright light in response to the portion and velocity parameters and control the dynamic gradient accordingly.

11. A method of providing information to a pilot in an aviation environment, the method comprising:

providing light associated with the information to a combiner, wherein the combiner comprises a waveguide have an input and an output, the light associated with the information traveling from the input to the output by total internal reflection within the waveguide, wherein bright light in the cockpit environment is provided through the waveguide into an eye box at a virtual location;

sensing a location of the bright light from the environment and determining the virtual location in response to data from a sensor array and

attenuating the bright light at the virtual location by utilizing at least one selectably opaque area wherein the at least one selectably opaque area is shaped to correspond to a shape of the bright light at the virtual location.

12. The method of claim 11, further comprising executing software to perform real time computational analysis to determine the location of both a source of the bright light and the position of the eye.

13. The method of claim 11, wherein the determining uses an eye location, a velocity parameter of the aircraft, and a position parameter of the aircraft.

14. The method of claim 13, wherein the determining use, the velocity parameter and the position parameter to determine a future location of the bright light in an environment.

15. The method of claim 14, wherein the location of the bright light in the environment is triangulated to the location on the combiner using data from an eye sensor.

16. The method of claim 11, wherein the attenuating uses an LCD or a dynamic filter.

17. A head up display, comprising:

a waveguide combiner including an input grating and an output grating, wherein light associated with information travels from the input grating from the output grating by total internal reflection within the waveguide combiner, wherein bright light in an environment of the cockpit is virtually provided through the waveguide combiner into an eye box at a virtual location; and

a saturation mitigator disposed to prevent bright light from outside the waveguide combiner from being provided through the output grating and reaching the eye box, the saturation mitigator being selectably opaque in at least one area, the at least one area corresponding to the virtual location of the bright light, and wherein the at least one area is shaped to correspond to a shape of the bright light at the location.

18. The head up display of claim 17, further comprising a bright light sensor.

19. The head up display of claim 17, further comprising an eye sensor.

20. The head up display of claim 17, further comprising a processor for locating the bright light and correlating the location of the bright light to the area.