Vehicle surface

Abstract

A vehicle surface includes a set of retroreflectors configured to reflect, at least in part, incident hostile light towards a source of the incident hostile light.

Claims

1. A vehicle surface, comprising: a retroreflector configured to reflect, at least in part, incident hostile light towards a source of the incident hostile light, the retroreflector configured to be positioned on an outer surface of the vehicle, wherein the retroreflector includes a holographic interference coating on at least a first part of a surface of the retroreflector and an antireflective coating on at least a second part of the surface of the retroreflector.

2. The vehicle surface according to claim 1, wherein the retroreflector comprises one or more of a cube corner, a cat's eye, and a phase conjugate minor.

3. The vehicle surface according to claim 1, comprising a paint or lacquer overlaying, at least in part, the retroreflector.

4. The vehicle surface according to claim 1, further comprising a first discrete retroreflector and a second discrete retroreflector.

5. The vehicle surface according to claim 1, comprising one of an embossing and a film comprising the retroreflector.

6. The vehicle surface according to claim 1, wherein the retroreflector has a dimension in a range from 5 m to 100 cm.

7. The vehicle surface according to claim 1, wherein the retroreflector covers at least 20% of an area of the vehicle surface.

8. A vehicle comprising the vehicle surface according to claim 1.

9. The vehicle according to claim 8, wherein the vehicle is an aircraft.

10. A method of controlling hostile light incident on a vehicle, the method comprising: reflecting, at least in part, the incident hostile light towards a source thereof using the vehicle surface according to claim 1, the vehicle surface being part of the vehicle.

11. The method according to claim 10, wherein the hostile light has a wavelength in a range from 380 nm to 760 nm.

12. The method according to claim 10, wherein the source comprises a laser, and wherein the vehicle is an aircraft.

13. The vehicle surface according to claim 1, wherein the retroreflector covers at least 60% of an area of the vehicle surface.

14. The vehicle surface according to claim 1, wherein the retroreflector comprises a spheroidal or spherical bead that is at least partially coated with an optical interference coating.

15. The vehicle surface according to claim 14, wherein the spheroidal or spherical bead includes a metalized surface.

16. The vehicle surface according to claim 1, wherein the retroreflector is at least partially coated with an optical interference coating, the optical interference coating configured to be ablated by at least a portion of electromagnetic radiation of the incident hostile light, thereby absorbing energy from the electromagnetic radiation.

17. A coating material for coating a vehicle surface, the coating material comprising a retroreflector configured to reflect, at least in part, incident hostile light towards a source of the incident hostile light, the retroreflector configured to be positioned on an outer surface of a vehicle, wherein the retroreflector comprises one or more of a cube corner, a cat's eye, and a phase conjugate mirror, and wherein the retroreflector includes a holographic interference coating on at least a first part of a surface of the retroreflector and an antireflective coating on at least a second part of the surface of the retroreflector.

18. A method of providing a vehicle surface, the method comprising: arranging a retroreflector on a substrate, wherein the retroreflector is configured to reflect, at least in part, incident hostile light towards a source of the incident hostile light, the retroreflector configured to be positioned on an outer surface of a vehicle, and wherein the retroreflector includes a holographic interference coating on at least a first part of a surface of the retroreflector and an antireflective coating on at least a second part of the surface of the retroreflector.

19. The method according to claim 18, comprising overlaying, at least in part, the retroreflector with a paint or lacquer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For a better understanding of the invention, and to show how exemplary embodiments of the same may be brought into effect, reference will be made, by way of example only, to the accompanying diagrammatic Figures, in which:

(2) FIG. 1 is a photograph showing dazzle due to an eye safe (<1 mW) laser;

(3) FIG. 2 is a photograph of the same scene as FIG. 1, under ambient lighting, for comparison;

(4) FIG. 3 schematically depicts a vehicle surface according to an exemplary embodiment;

(5) FIG. 4 schematically depicts a vehicle surface according to an exemplary embodiment;

(6) FIG. 5 schematically depicts a vehicle surface according to an exemplary embodiment;

(7) FIG. 6 schematically depicts a vehicle according to an exemplary embodiment;

(8) FIG. 7 schematically depicts a method according to an exemplary embodiment; and

(9) FIG. 8 schematically depicts a method according to an exemplary embodiment.

DETAILED DESCRIPTION OF THE DRAWINGS

(10) FIG. 3 schematically depicts a vehicle surface 10 according to an exemplary embodiment.

(11) The vehicle surface 10 comprises thereon and/or therein a set of retroreflectors 100, including a first retroreflector 100A, configured to reflect, at least in part, incident hostile light .sub.incident towards a source thereof.

(12) In this example, the first retroreflector 100A is a bead, particularly a spherical bead, provided on a substrate 1. In this example, the first retroreflector 100A is completely coated with an optical interference coating 110, particularly a holographic interference coating 110, provided as a film 120 on a surface of the bead. The particle 130 is formed from optical glass and has a radius of 100 m. In this example, the set of retroreflectors 100 is coated with a flowable formulation, cured to a solid (not shown).

(13) coating 215 is outermost or generally outermost. In this way, retroreflection of at least some of the incident electromagnetic radiation, towards the source (e.g. a laser) thereof, is improved.

(14) In this way, at least some incident electromagnetic radiation .sub.incident reflects off a front surface of the first retroreflector 100A (i.e. as reflected electromagnetic radiation .sub.reflected, external) while at least some incident electromagnetic radiation .sub.incident is transmitted into the first retroreflector 100A (i.e. enters the bead 130 as admitted electromagnetic radiation .sub.admitted). At least some of the admitted electromagnetic radiation .sub.admitted transmitted into the first retroreflector 100A is subsequently transmitted out of the first retroreflector 100A (i.e. exits the bead as transmitted electromagnetic radiation .sub.transmitted) (not shown). However, at least some of the electromagnetic radiation .sub.admitted transmitted into the first retroreflector 100A is trapped in the bead 130, due to reflection by the optical interference coating, for example the holographic interference coating 110. The trapped electromagnetic radiation .sub.reflected,internal may ablate at least a part of the optical interference coating 110, for example the holographic interference coating, and/or the first retroreflector 100A, thereby absorbing energy of the trapped electromagnetic radiation and protecting the underlying article. At least some of the trapped electromagnetic radiation .sub.reflected,internal may exit the first retroreflector 100A via the front surface i.e. as reflected electromagnetic radiation .sub.reflected.

(15) In use, the set of retroreflectors 100 on the vehicle surface 10 is such that the surface of the vehicle is covered in many layers of the beads, thereby providing a protective layer. This allows for the destruction and ablation of the protective layer by the incident hostile light from the source without breach of protection. Protection may be required only for a limited time due to a nature of the source only being able to target the vehicle for a specific time. The holographic interference coating 110 may be tuned for a predetermined wavelength or a range of predetermined wavelengths. Since lasers from sources are generally monochromatic, protection may be thus provided against predetermined sources.

(16) FIG. 4 schematically depicts a vehicle 20 according to an exemplary embodiment. The vehicle surface 20 is similar to the vehicle surface 10 and like features are denoted by like reference signs. However, in contrast to the vehicle surface 10, a holographic interference coating 210 is provided on at least a first part of surfaces of the first retroreflector 200A and an antireflective coating 215 is provided on at least a second part of the surfaces of the first retroreflector 200A. Particularly, half of the surface of the first retroreflector 200A is covered by the holographic interference coating 210 and the other half of the surface of the first retroreflector 200A is covered by the antireflective coating 215. Coating one half of the surface of the first retroreflector 200A with the holographic interference coating 210 allows for greater reflection whilst ensuring that energy is allowed to exit the bead whilst the antireflective coating 215 on the front side allows for easier admittance of the incident hostile light and/or transmittance of the retroreflected light. Preferably, some or all of the retroreflectors of the set of retroflectors 200 are oriented, for example electrostatically, whereby the antireflective coating 215 is outermost or generally outermost. In this way, retroreflection of at least some of the incident electromagnetic radiation, towards the source (e.g. a laser) thereof, is improved.

(17) FIG. 5 schematically depicts a vehicle surface 30 according to an exemplary embodiment.

(18) The vehicle surface 30 comprises thereon and/or therein a set of retroreflectors 300, including a first retroreflector 300A, configured to reflect, at least in part, incident hostile light .sub.incident towards a source thereof.

(19) In this example, the first retroreflector 300A is a corner reflector, provided on a substrate 1.

(20) Using a corner reflector arrangement allows for reflection to occur as the internal surfaces may be made from highly polished metal (such as steel), for example with a holographic interference coating applied to the internal surfaces. This would allow for the metallic structure to be cooled using traditional cooling methods such as phase changing, radiators etc. If the laser ablates the holographic interference coating the underlying structure provides additional protection. It is envisaged that many small structures will be placed along the asset to be protected to provide full coverage.

(21) FIG. 6 schematically depicts a vehicle V according to an exemplary embodiment. In this example, the vehicle V is an aircraft including vehicle surfaces 30 (shown as red circles), as described above with reference to FIG. 5.

(22) FIG. 7 schematically depicts a method according to an exemplary embodiment. Particularly, the method is of providing a vehicle surface.

(23) At S701, a set of retroreflectors, including a first retroreflector, is arranged on a substrate, wherein the set of retroreflectors is configured to reflect, at least in part, incident hostile light towards a source thereof, thereby providing the vehicle surface.

(24) Optionally, the method comprises overlaying, at least in part, the set of retroreflectors with a paint or lacquer.

(25) The method may include any of the steps described herein.

(26) FIG. 8 schematically depicts a method according to an exemplary embodiment. Particularly, the method is of controlling hostile light incident on a vehicle.

(27) At S801, the incident hostile light is reflected, at least in part, towards a source thereof using a set of retroreflectors, including a first retroreflector, on and/or in a vehicle surface of the vehicle.

(28) Optionally, the hostile light has a wavelength in a range from 380 nm to 760 nm.

(29) Optionally, the source comprises and/or is a laser and/or wherein the vehicle comprises and/or is an aircraft.

(30) The method may include any of the steps described herein.

(31) Although a preferred embodiment has been shown and described, it will be appreciated by those skilled in the art that various changes and modifications might be made without departing from the scope of the invention, as defined in the appended claims and as described above.

(32) Attention is directed to all papers and documents which are filed concurrently with or previous to this specification in connection with this application and which are open to public inspection with this specification, and the contents of all such papers and documents are incorporated herein by reference.

(33) All of the features disclosed in this specification (including any accompanying claims and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at most some of such features and/or steps are mutually exclusive.

(34) Each feature disclosed in this specification (including any accompanying claims, and drawings) may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

(35) The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.