Method and apparatus for calibrating glare-shielding glasses

• US 20060119785A1
• Filed: 11/30/2005
• Published: 06/08/2006
• Est. Priority Date: 12/03/2004
• Status: Active Grant

• Current Assignee: Christopher S. Mullin
• Original Assignee: Dynamic Fax Inc.
• Inventors: Mullin, Christopher S., Heuser, Timothy D.
• Granted Patent: US 7,585,068 B2
• Time in Patent Office: Days
• US Class Current: 351/44
• CPC Class Codes: G02C 7/101 having an electro-optical light valve electro-optical elements per se G02F

Abstract

The present invention is directed to a method and apparatus for assuring that dynamic glare-shielding devices are properly characterized for the optical arrangement of a particular user by using a plurality of calibration points, thereby assuring the maximum effectiveness of such devices

Claims

1. A method for calibrating a glare-shield comprising:

measuring at least two relationships between a glare source and a glare calibration position; and

using the measured relationships, determining the location of a darkened spot on the glare shield in response to a specific location of glare on a glare sensor.

2. The method of claim 1, further including tracking the position of a pupil with a pupil tracking system, wherein the measured relationships are adjusted according to the position of the pupil.

3. The method of claim 1, wherein at least three calibration points are used to measure the relationships between the glare source and the calibration position, and where the location of the darkened spot is calculated from a quadratic equation.

4. The method of claim 1, further comprising testing the validity of the calibration measurements by comparing a spread in pixel positions to a maximum allowable spread.

5. The method of claim 1, wherein measuring at least two relationships comprises:

determining a first relationship between the glare source, a first darkened region on the glare-shield, and the calibration position;

concurrently recording the first position of the glare source on a photodetector associated with the glare-shield to produce a first calibration data point;

determining a second relationship between the glare source, a second darkened region on the glare-shield, and the calibration position; and

concurrently recording the second position of the glare source on the photodetector associated with the glare-shield to produce a second calibration data point.

6. The method of claim 5, wherein the first darkened region is spaced apart from the second darkened region.

7. The method of claim 5, wherein the first and second calibration data points are recorded as at least two-dimensional positions.

8. The method of claim 5, wherein determining the relationship comprises:

providing a glare source at a position in front of the glare-shield;

darkening a region on the glare-shield; and

adjusting the relative relationship between the darkened region and the glare source until the darkened region lies along a line between the glare source and the calibration position.

9. The method of claim 8, further comprising signaling a microcontroller for the glare-shield that a calibration point is complete when the darkened region lies between the glare source and the desired shielding point.

10. The method of claim 5, wherein determining the location of the darkened spot on the glare shield in response to the specific location of glare on a glare sensor comprises:

calculating a first optical ratio (H/B);

calculating a first offset parameter Q;

calculating a second offset parameter Q′

; and

using the optical ratio and first and second offset parameters, in conjunction with the specific location of glare on a glare sensor, to determine the location of the darkened spot.

11. The method of claim 6, wherein the first and second calibration data points are stored in response to a calibration signal.

12. The method of claim 11, wherein the calibration signal is generated in response to a button being pressed.

13. The method of claim 11, wherein the calibration signal is generated in response to a coded signal.

14. The method of claim 13, wherein the coded signal is generated by the glare source.

15. The method of claim 10, wherein the optical ratio and the offset parameters are further modified to shield a position at a different distance from the glare-shield

16. The method of claim 10, wherein determining the location of the darkened spot further comprises calculating a non-parallel adjustment factor to adjust for at least one angle of orientation between the photodetector and the glare-shield.

17. The method of claim 10, wherein determining the location of the darkened spot further comprises calculating a non-planar adjustment factor to adjust for curvature in the glare-shield.

18. The method of claim 5, wherein the glare source produces a visible output that is detected by the photodetector.

19. The method of claim 5, wherein the glare source produces a non-visible output that is detected by the photodetector.

20. The method of claim 5 wherein a position of the glare source is calculated as a function of a plurality of pixel positions in the photodetector detecting the glare source.

21. The method of claim 12, wherein the calibration signal is triggered by a wearer of the glare shield observing the darkened region covering at least a portion of the glare source.

22. The method of claim 12, wherein the calibration signal is triggered by an observer detecting that the darkened region is at least partially aligned with the glare source and the calibration position.

23. A system for the calibration of a glare-shield, comprising:

at least one glare source;

a darkened region on the glare-shield;

a calibration position for concurrently perceiving the glare source and the darkened region and adjusting the location of the darkened region relative to the glare source;

a microcontroller for determining at least a first and a second relationship between the location of the glare source, the darkened region on the glare-shield, and the calibration position;

memory, associated with said microcontroller, for recording first and second calibration data points for positions of the glare source on a photodetector associated with the glare-shield when the darkened region occludes the glare source; and

said microcontroller further determining, based upon the first and second calibration data points, a position of the darkened region in response to the glare source location on the photodetector.

24. The system of claim 23, wherein said microcontroller further adjusts the location of the darkened region relative to the glare source until the darkened region lies between the glare source and the calibration position.

25. The system of claim 24, further comprising means for signaling the controller for the glare-shield that a calibration point is complete.

26. The system of claim 25, wherein the means for signaling includes an electrical switch in the form of a button.

27. The system of claim 25, wherein the means for signaling includes a signal transmitter and receiver.

28. The system of claim 25, wherein the signal is a coded a signal from the glare source, and where said microcontroller monitors an on/off state of the glare source over a period of time to detect the coded signal.