Granted Patent B2

US 12,256,152 · App. 17/594,506 · Granted Mar 18, 2025

Inventors: Santeri Jeremias Seppä (VTT, FI); Teemu Kääriäinen (VTT, FI); Thomas Fordell (VTT, FI)

Assignee: TEKNOLOGIAN TUTKIMUSKESKUS VTT OY

H04N23/74G02B23/12F41G1/35F41G1/36G03B15/02

Abstract

Claims (31)

1. A system for providing stealthy vision, comprising:

a source element configured to provide electromagnetic radiation at a predetermined wavelength in order to illuminate a target, wherein the electromagnetic radiation is provided without controlling at least one of temperature or electrical current; and

a camera configured to image the target to be illuminated at the predetermined wavelength; wherein,

the source element is configured to provide electromagnetic radiation comprising shortwave infrared light; and

the predetermined wavelength comprises a wavelength in a region of the near infrared spectrum wherein the absorption features of an atom or a molecule present in a medium through which the electromagnetic radiation propagates form a continuum, that is a wavelength region wherein two or more narrow absorption lines are proximate to each other that they form a single absorption area with a width greater than that of a single absorption line so that the range of the electromagnetic radiation in the medium is limited for all wavelengths within the continuum; and wherein

the region corresponds to a wavelength range centered at 1382.8 nm, 1388.1 nm or 1392.4 nm.

2. The system for providing stealthy vision of claim 1 , wherein the wavelength region has a width of more than 0.2 nm.

3. The system for providing stealthy vision according to claim 1 , wherein the wavelength region has a width of more than 0.5 nm.

4. The system for providing stealthy vision according to claim 1 , wherein the source element comprises a laser source configured to provide the predetermined wavelength.

5. The system for providing stealthy vision according to claim 1 , wherein the source element comprises a broadband source of electromagnetic radiation.

6. The system for providing stealthy vision according to claim 1 , wherein the source element comprises a filter element configured to filter the electromagnetic radiation to the predetermined wavelength.

7. The system for providing stealthy vision according to claim 1 , wherein the camera comprises a short wave infrared, SWIR, camera.

8. The system for providing stealthy vision according to claim 1 , wherein the atom or molecule present in the medium through which the electromagnetic radiation propagates comprises H2O.

9. The system for providing stealthy vision according to claim 1 , wherein the source element is adjustable for choosing a predetermined wavelength.

10. A method for providing stealthy vision, comprising:

illuminating a target with electromagnetic radiation comprising shortwave infrared light at a predetermined wavelength from a source element, wherein the source element provides the electromagnetic radiation without controlling at least one of temperature or electrical current; and

imaging the illuminated target with camera configured to image the target to be illuminated at the predetermined wavelength; wherein

the predetermined wavelength comprises a wavelength in a region of the near infrared spectrum wherein the absorption features of an atom or a molecule present in a medium through which the electromagnetic radiation propagates form a, that is a wavelength region wherein two or more narrow absorption lines are proximate to each other that they form a single absorption area with a width greater than that of a single absorption line so that the range of the electromagnetic radiation in the medium is limited for all wavelengths within the continuum; and wherein

the region corresponds to a wavelength range centered at 1382.8 nm, 1388.1 nm or 1392.4 nm.

11. The method for providing stealthy vision according to claim 10 , wherein the wavelength region has a width of more than 0.2 nm.

12. The method for providing stealthy vision according to claim 10 , wherein the wavelength region has a width of more than 0.5 nm.

13. The method for providing stealthy vision according to claim 10 , further comprising adjusting the source element in order to choose a predetermined wavelength from several predetermined wavelengths.

14. An apparatus, comprising:

a system for providing stealthy vision, comprising:

a source element configured to provide electromagnetic radiation at a predetermined wavelength in order to illuminate a target, wherein the source element provides the electromagnetic radiation without controlling at least one of temperature or electrical current;

a camera configured to image the target to be illuminated at the predetermined wavelength; wherein

the source element is configured to provide electromagnetic radiation comprising shortwave infrared light; and

the predetermined wavelength comprises a wavelength in a region of the near infrared spectrum wherein the absorption features of an atom or a molecule present in a medium through which the electromagnetic radiation propagates form a continuum, that is a wavelength region wherein two or more narrow absorption lines are proximate to each other that they form a single absorption area with a width greater than that of a single absorption line so that the range of the electromagnetic radiation in the medium is limited for all wavelengths within the continuum; and wherein

the region corresponds to a wavelength range centered at 1382.8 nm, 1388.1 nm or 1392.4 nm; and

a processor configured to cause the apparatus to carry out the method of claim 10 .

15. The apparatus of claim 14 , wherein the apparatus comprises a handheld electronic device.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (33)