APPARATUS FOR HIGH CONTRAST OPTICAL SIGNALING, AND EXEMPLARY APPLICATIONS

• US 20130093581A1
• Filed: 10/10/2012
• Published: 04/18/2013
• Est. Priority Date: 10/12/2011
• Status: Active Grant

• Current Assignee: IMRA America Incorporated (Aisin Corp.)
• Original Assignee: IMRA America Incorporated (Aisin Corp.)
• Inventors: ARAI, Alan Y.
• Granted Patent: US 9,333,900 B2
• Time in Patent Office: Days
• US Class Current: 340/435
• CPC Class Codes: B60Q 1/00 Arrangement of optical signalling or lighting devices, the mounting or supporting thereof or circuits therefor for lighting vehicle interior B60Q3/00
• CPC Class Codes: B60R 1/1207 with lamps; with turn indicators
• CPC Class Codes: B60R 2001/1215 with information displays
• CPC Class Codes: G09G 2380/06 Remotely controlled electronic signs other than labels
• CPC Class Codes: G09G 2380/10 Automotive applications

Abstract

A display apparatus generates a high visibility optical signal, such as an ICON, the ICON comprising a symbol, shape, or other image-like representation. The ICON becomes visible at an observation point during an illumination ON-state. The ICON may be formed as a portion of display medium, for example as a machined portion of a mirror capable of forming images of a scene by reflection in normal operation. The visibility of the ICON in the illumination OFF-state from an observation point is sufficiently low such that the normal operation of the display medium is maintained. The display apparatus may be used in a blind spot warning system for a vehicle. Visible wavelength LEDs, RGB LEDs and/or diode lasers may be utilized as an illumination source. Ultrashort laser processing or other methods for material modification may be utilized to form microscopic features which distribute incident light, increasing the visibility of the optical signal at an observation point in an ON-state, with very low visibility in the OFF-state and minimal effect on the image in the display medium in the OFF state.

Claims

1. An optical signaling apparatus, comprising:

a controllable first source of illumination capable of providing ON and OFF illumination states; and

an optical medium arranged to receive illumination from said controllable first source and capable of receiving illumination from a second source, wherein a region of said medium is arranged in such a way that a detectable optical signal is visible therefrom during an illumination ON state of said controllable first source, and wherein said region of said medium is indistinguishable from other parts of the medium during an OFF illumination state of said controllable first source, notwithstanding the arrangement of said region.

2. The optical signaling apparatus of claim 1, wherein said region of said medium forms an image with said illumination from said second source.

3. The optical signaling apparatus of claim 1, wherein said region of said optical medium comprises microscopic features formed in said medium, and said microscopic features distribute energy from said controllable first source over a viewing angle so as to form said detectable optical signal.

4. The optical signaling apparatus of claim 1, wherein said optical medium comprises a transparent or translucent substrate with a thin, opaque or semi-opaque film.

5. The optical signaling apparatus of claim 1, wherein said optical medium comprises a mirror, the mirror comprising a transparent substrate and a reflective coating disposed thereon.

6. The optical signaling apparatus of claim 1, wherein said optical medium comprises a mirror, said mirror comprising a transparent substrate and a reflective coating disposed thereon, and said region comprises microscopic features that substantially diffract energy received from said controllable first source in an ON state to generate said optical signal, and said microscopic features are sufficiently small to be nearly invisible when said controllable first source is in the OFF state.

7. The optical signaling device of claim 6, wherein energy is diffracted over a full angle of at least about 10 degrees.

8. The optical signaling apparatus of claim 1, wherein said microscopic features are formed by selectively removing a depth-wise portion of the reflective coating.

9. The optical signaling apparatus of claim 1, where said controllable first source comprises at least one LED.

10. The optical signaling apparatus of claim 1, wherein said controllable first source comprises an RGB LED source.

11. The optical signaling apparatus of claim 1, wherein said second illumination source emits natural illumination.

12. The optical signaling apparatus of claim 1, wherein said second illumination source emits energy from an artificial source of illumination.

13. The optical signaling apparatus of claim 1, wherein a portion of illumination from the controlled first source is incident on the region of medium from first directions, and at least a portion of illumination from second source is source is incident from second directions that overlap the first directions.

14. The optical signaling apparatus of claim 1, wherein said apparatus is configured as a portion of a warning system of a vehicle, and said optical signal is in the form of an ICON.

15. A laser-based method comprising:

irradiating a portion of an optical medium with laser pulses to selectively remove at least a depth-wise portion of material from a region of said medium, and to form a predetermined pattern of microscopic features arranged in such a way that a detectable optical signal is visible therefrom with illumination from a first source, said medium capable of receiving illumination from a second source, and wherein said region of said medium is essentially indistinguishable from other parts of the medium without illumination from said first source, notwithstanding the arrangement of said region.

16. The method of claim 15, wherein said optical medium comprises a transparent or translucent substrate with a thin, opaque or semi-opaque film.

17. The method of claim 15, wherein said optical medium comprises a mirror, said mirror comprising a transparent substrate and a reflective coating disposed thereon.

18. The method of claim 15, wherein said optical medium comprises a mirror, said mirror comprising a transparent substrate and a reflective coating disposed thereon, and said region comprises microscopic features that substantially diffract energy received from said controllable first source to generate the detectable signal, and said microscopic features are sufficiently small to be nearly invisible without illumination from the first source.

19. The method of claim 15, wherein said microscopic features are formed by selectively removing a depth-wise portion of said reflective coating.

20. The method of claim 15, wherein ultrashort pulses are generated, said ultrashort pulses having a pulse width in the range from about 100 fs to about 10 ps.

21. The method of claim 15, wherein said laser pulses are generated at a repetition rate of at least about 1 KHz.

22. The method of claim 15, wherein said laser pulses are generated at a repetition rate of at least about 100 KHz.

23. A method comprising:

modifying a portion of an optical medium to selectively remove at least a depth-wise portion of material from a region of said medium, and to form a predetermined pattern of microscopic features arranged in such a way that a detectable optical signal is visible therefrom with illumination from a first source, said medium capable of receiving incident illumination from a second source, and wherein said region of said medium is essentially indistinguishable from other parts of the medium without illumination from said first source, notwithstanding the arrangement of said region.

24. The method of claim 23, wherein said method comprises mechanically scribing or etching.

25. An optical signaling method, comprising:

controlling a first source of illumination capable of providing ON and OFF illumination states; and

utilizing an optical medium to receive illumination from said first source and to receive illumination from a second source, wherein a region of said medium is arranged in such a way that a detectable optical signal is visible therefrom during an illumination ON state of said first source, and wherein said region of said medium is essentially indistinguishable from other parts of the medium during an OFF illumination state of said first source, notwithstanding the arrangement of said region.

26. The optical signaling method of claim 25, wherein said method provides a warning indication for use during movement.

27. A visual warning system, comprising:

a controllable first source of illumination capable of providing ON and OFF illumination states; and

a mirror arranged to receive illumination from said controllable first source and capable of receiving illumination from a second source different than the first source, wherein a region of said mirror comprises microscopic features that distribute energy from said controllable first source over a viewing angle so as to form an optical signal visible therefrom during an illumination ON state of said controllable first source, wherein said visible optical signal is in the form of an ICON comprising a symbol, shape, or other image-like representation, and wherein said region of said mirror is indistinguishable from other parts of the mirror during an OFF illumination state of said controllable first source, notwithstanding the arrangement of said region of microscopic features, wherein said region of said mirror forms a portion of a visible mirror image with said illumination from said second source.

28. A visual warning system, comprising:

a controllable first source of illumination capable of providing ON and OFF illumination states; and

a mirror arranged to receive illumination from said controllable first source and capable of receiving illumination from a second source different than the first source, wherein a region of said mirror comprises microscopic features that distribute energy from said controllable first source over a viewing angle so as to form an optical signal visible therefrom during an illumination ON state of said controllable first source, wherein said visible optical signal is in the form of an ICON comprising a symbol, shape, or other image-like representation, and wherein said ICON is essentially invisible during an OFF illumination state of said controllable first source, notwithstanding the arrangement of said region of microscopic features and a presence of illumination from said second source on or within said region, and wherein said region of said mirror forms a portion of a visible mirror image with said illumination from said second source.

29. The visual warning system of claim 28, wherein said system comprises a plurality of ICONs and a corresponding plurality of controllable sources of illumination, said ICONs comprising at least two different shapes or symbols.