Illumination and imaging devices and methods

• US 20030047683A1
• Filed: 09/10/2002
• Published: 03/13/2003
• Est. Priority Date: 02/25/2000
• Status: Active Grant

• Current Assignee: Teledyne FLIR LLC (Teledyne Technologies Incorporated)
• Original Assignee: Qinetiq Limited (QinetiQ Group PLC)
• Inventors: Kaushal, Tej
• Granted Patent: US 7,579,592 B2
• Time in Patent Office: Days
• US Class Current: 250/330
• CPC Class Codes: A61B 2090/366 using projection of images directly onto the body
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/489 Blood vessels
• CPC Class Codes: F21W 2131/406 for theatres, stages or film studios
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 5/0022 for sensing the radiation of moving bodies
• CPC Class Codes: G02B 23/12 with means for image conversion or intensification
• CPC Class Codes: H04N 9/3161 using laser light sources using laser beams scanning the display screen H04N9/3129

Abstract

A thermal torch (12) comprises an infrared camera (22) and a visible light emitter (28, 26) arranged so as to illuminate hot objects with visible light. This projection of visible light onto the scene, rather than observing it at infrared wavelengths converted to visible light by a display screen, makes viewing the scene more natural. Applications include medical imaging equipment, nightdriving systems, stage lights, and security lights. The profile of the beam of visible light can be modulated with a beam profiler (26) which may be an LCD. The infrared camera (22) and visible projector (28, 26) may be bore-sighted to facilitate overlying of the visible projected image onto the scene.

Claims

1. A projector device comprising:

a passive infrared detector adapted to detect thermal infrared radiation emitted by a body in an observed scene and incident upon the device from a direction;

an emitter adapted to emit a beam of radiation of visible light, and emitted beam control means adapted to control the direction of the emitted visible light beam to direct it in substantially the same direction as that from which came the detected thermal infrared radiation.

3. A device according to claim 1 or claim 2 in which the emitter has an emitted beam patterner, and in which the detector is adapted to detect the cross-sectional profile, or pattern, of an object passively detected in an observed scene in infrared, or first wavelength, and in which the emitter is adapted to emit an emitted beam with a variable cross-sectional profile which is modulated by the beam patterner to match the profile or pattern in infrared or first wavelength, and to superpose an equivalent visible light pattern over the infrared or first wavelength pattern in the observed scene.

4. A device according to any preceding claim in which an optical alignment element is provided to register the emitted beam with the detected body, the alignment element being at least partially reflective to radiation of one of the thermal infrared, or first, wavelengths and visible light, and at least partially transmissive to radiation of the other of the thermal infrared, or first wavelength, and visible light.

5. A device according to claim 4 in which the alignment element comprises a beam splitter.

6. A device according to any preceding claim comprising a hand-held torch.

9. A device according to any preceding claim in which signals produced by the detector are passed substantially unprocessed to the emitter.

10. A device according to any preceding claim which has a sensor sensitive to visible light, and a directional or imaging detector, and a directional or image projector as the emitter, and deselection control means being adapted to identify areas of the scene being observed that are the source of a significant amount of radiation of visible light to the device, and being adapted to deselect those regions for illumination by the visible light emitter.

11. A device according to any preceding claim which has a detecting imager with a plurality of pixels and an emitter adapted to project an image with substantially the same number of pixels.

2. A projector device comprising a passive detector adapted to detect directional information regarding waves or radiation of a first, non-visible wavelength incident upon the device from a direction;

an emitter adapted to emit a beam of visible light, and emitted beam control means adapted to control the direction of the emitted visible light beam to direct it in substantially the same direction as that from which came the detected waves or non-visible radiation.

7. A device according to claim 3 or any claim depending directly or indirectly from claim 2 in which the beam patterner comprises a spatial light modulator (SLM) adapted to control an image emitted by the emitter.

8. A device according to claim 7 in which the spatial light modulator is provided at or between an alignment element adapted to align an emitted visible light image with a detected image thermal infrared, or first wavelength radiation, and a source of visible light.

12. A method visibly representing a thermal mapping of an observed scene comprising receiving thermal infrared radiation of a first wavelength and using the received infrared radiation to control the projection of visible light onto the observed scene, the visible light being projected in a visible light pattern onto the observed scene that mirrors and overlays the thermal infrared map of the observed scene.

15. A method of improving the safely of driving in the dark comprising mounting on a vehicle a visible light projector which operates in accordance with any one of claims 12 to 14 and illuminating thermal objects in an observed scene with visible light.

13. A method of visibly representing a mapping of an observed scene in a non-visible information carrier domain from which directional and intensity information about the observed scene has been obtained comprising detecting a non-visible domain pattern from the observed scene and projecting an equivalent corresponding visible light pattern onto the observed scene, with visible light patterns superimposed upon the corresponding non-visible domain patterns observed.

14. A method according to claim 13 comprising providing a user with a hand-held torch to perform the visible light pattern illumination of the non-visible domain patterns.

16. A method of reducing the size of a passive thermal infrared imaging array in a device adapted to show a user the shape of a hot body, the method comprising using a passive thermal infrared sensor to control and pattern the output of a visible band projector to illuminate the thermal body with visible light with a pattern that corresponds to the thermal image obtained by the sensor.

17. A method of imaging anatomical structures comprising using a non-visible band imager to generate image-controlling signals relating to the structure of the anatomical structure of interest and using those signals to control the output of a visible band projector to project onto the person or animal'"'"'s body an image in visible light of the structure with a pattern that corresponds to the image produced using the non-visible band imager.