Infrared camera with infrared-transmissive dome systems and methods

• US 8,905,311 B2
• Filed: 03/11/2010
• Issued: 12/09/2014
• Est. Priority Date: 03/11/2010
• Status: Active Grant

• Current Assignee: Teledyne FLIR LLC (Teledyne Technologies Incorporated)
• Original Assignee: FLIR Systems, Inc. (Teledyne Technologies Incorporated)
• Inventors: Hoelter, Theodore R., Sharp, Barbara, Burt, Warn, Pietsch, Robert, Tremblay, Marcel, Lewis, Earl R.
• Primary Examiner(s): KELLY, RAFFERTY D
• Application Number:
  US12/721,870
• Publication Number:
  US 20110220797A1
• Time in Patent Office: 1,734 Days
• Field of Search: 348/164, 264/1.1, 359/350, 359/359, 235/439
• US Class Current: 235/439
• CPC Class Codes: B29C 2043/3615 Forming elements, e.g. mandrels or rams or stampers or pistons or plungers or punching devices
• CPC Class Codes: B29C 43/021 characterised by the shape of the surface
• CPC Class Codes: B29C 43/36 Moulds for making articles of definite length, i.e. discrete articles
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 5/04 Casings
• CPC Class Codes: G01J 5/046 Materials; Selection of thermal materials
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0806 Focusing or collimating elements, e.g. lenses or concave mirrors
• CPC Class Codes: G01J 5/0875 Windows; Arrangements for fastening thereof

Abstract

Systems and methods are disclosed that provide an infrared-transmissive dome, such as for infrared imaging applications. For example, an infrared camera system includes a housing having a lens coupled to the housing and an infrared detector within the housing configured to receive infrared energy passing through the lens. An infrared-transmissive dome, coupled to the infrared camera system, includes a main body providing a hollow, hemispherical-shaped dome, with the main body made of an ultra-high molecular weight or a very-high molecular weight polyethylene material. The main body may have a wall thickness equal to or less than approximately 0.012 inches to allow infrared transmittance greater than approximately sixty five percent through the main body to the lens for infrared imaging in a wavelength range of approximately three to fourteen micrometers.

Claims

1. An infrared camera system, comprising:

a housing;

a lens coupled to the housing;

an infrared-transmissive dome coupled to the infrared camera system; and

an infrared detector within the housing and configured to receive infrared energy passing through the lens and the infrared-transmissive dome to capture infrared images, wherein;

the infrared-transmissive dome comprises a main body providing a hollow, hemispherical-shaped dome;

the main body is self-supporting and is made of an ultra-high molecular weight or a very-high molecular weight polyethylene material; and

the main body has a wall thickness equal to or less than 0.012 inches and is configured to allow infrared transmittance greater than approximately sixty five percent through the main body to the lens for infrared imaging in a wavelength range of approximately three to fourteen micrometers.

2. The infrared camera system of claim 1, wherein a ratio of the wall thickness to a diameter of the infrared-transmissive dome is approximately 0.004 or less and the wall thickness is equal to or greater than approximately 0.005 inches.

3. The infrared camera system of claim 1, wherein a peak-to-peak variation of the wall thickness is approximately 0.0001 inches or less over any contiguous area defined by a pi/16 solid angle, a variation of the wall thickness is approximately 0.001 inches or less for the main body, and a radius of curvature of the main body varies by approximately ten percent or less from a mean radius of curvature over any contiguous area defined by a pi/16 solid angle.

4. The infrared camera system of claim 1, comprising:

a flange formed as part of and along an edge of the main body;

wherein the flange is made of the ultra-high molecular weight or very-high molecular weight polyethylene material; and

wherein the flange has a wall thickness greater than 0.010 inches.

5. The infrared camera system of claim 4, wherein the flange comprises a metal ring enclosed at least partially within the ultra-high molecular weight or very-high molecular weight polyethylene material.

6. The infrared camera system of claim 4, wherein the flange comprises a stepped portion or a curved-shaped portion to mate with a corresponding portion of the housing.

7. The infrared camera system of claim 1, wherein the main body is made of the ultra-high molecular weight polyethylene material and the very-high molecular weight polyethylene material.

8. The infrared camera system of claim 1, wherein the ultra-high molecular weight polyethylene material and/or the very-high molecular weight polyethylene material includes an additive to provide ultraviolet protection.

9. The infrared camera system of claim 8, wherein the additive includes a zinc sulfide, a titanium dioxide, a zinc oxide, an oligomeric-hindered amine-light stabilizer, and/or a hindered amine light stabilizer.

10. The infrared camera system of claim 1, wherein the infrared-transmissive dome comprises a thin sheet of the ultra-high molecular weight or very-high molecular weight polyethylene material layered over the main body, wherein the thin sheet has a wall thickness equal to or less than the wall thickness of the main body and includes an additive to provide ultraviolet protection and/or translucence to visible wavelengths, and wherein the infrared-transmissive dome provides greater than approximately sixty five percent transmission to infrared wavelengths within approximately eight to thirteen micrometers.

11. The infrared camera system of claim 1, wherein the ultra-high molecular weight or very-high molecular weight polyethylene material includes an additive such that the infrared-transmissive dome is generally translucent to visible wavelengths and provides greater than approximately sixty five percent transmission to infrared wavelengths within approximately eight to thirteen micrometers.

12. The infrared camera system of claim 11, wherein the additive includes a silicon material.

13. The infrared camera system of claim 1, wherein the infrared-transmissive dome is coupled to the infrared camera system by being couplable to the lens to allow infrared energy external to the infrared camera system to pass through the infrared-transmissive dome and the lens to the infrared detector.

14. The infrared camera system of claim 1, wherein the infrared-transmissive dome is coupled to the lens as a protective lens cover, and wherein the main body of the infrared-transmissive dome is spaced from an outer surface of the lens.

19. A method of forming the infrared-transmissive dome of Claim 1 to enclose at least a portion of the infrared camera system, the method comprising:

providing the ultra-high molecular weight or the very-high molecular weight polyethylene material within a compression mold to form the infrared-transmissive dome;

increasing a temperature of the compression mold;

applying pressure to the ultra-high molecular weight or very-high molecular weight polyethylene material via the compression mold;

decreasing the temperature of the compression mold; and

removing the ultra-high molecular weight or very-high molecular weight polyethylene material from the compression mold, wherein the ultra-high molecular weight or very-high molecular weight polyethylene material has been formed to provide the self-supporting, hollow, hemispherical-shaped dome having the main body with the wall thickness equal to or less than approximately 0.012 inches and configured to have the infrared transmittance greater than approximately sixty five percent through the main body for thermal infrared imaging by the infrared camera system in the wavelength range of approximately three to fourteen micrometers.

20. The method of claim 19, comprising:

inspecting the main body;

adding an additional amount of the ultra-high molecular weight or very-high molecular weight polyethylene material to certain areas of the main body that have undesired properties; and

repeating the increasing, the applying, and the decreasing operations followed by the removing of the infrared-transmissive dome from the compression mold formed from the ultra-high molecular weight or very-high molecular weight polyethylene material.

21. The method of claim 19, wherein the providing ultra-high molecular weight or very-high molecular weight polyethylene material within the compression mold is performed by a powder coat process.

22. The method of claim 19, wherein a ratio of the wall thickness to a diameter of the infrared-transmissive dome is approximately 0.004 or less, the wall thickness is equal to or greater than approximately 0.005 inches, a peak-to-peak variation of the wall thickness is approximately 0.0001 inches or less over any contiguous area defined by a pi/16 solid angle, a variation of the wall thickness is approximately 0.001 inches or less for the main body, and a radius of curvature of the main body varies by approximately ten percent or less from a mean radius of curvature over any contiguous area defined by a pi/16 solid angle.

23. The method of claim 19, further comprising coupling the infrared-transmissive dome to the infrared camera system to enclose at least a lens surface of the infrared camera system, wherein the main body of the infrared-transmissive dome is spaced from the lens surface.

24. The method of claim 19, wherein the ultra-high molecular weight or very-high molecular weight polyethylene material includes an additive to provide ultraviolet protection.

25. The method of claim 19, comprising applying a superhydrophobic coating on the hollow, hemispherical-shaped dome.

26. The method of claim 19, comprising treating the compression mold with a mold surface treatment to provide a low-friction mold surface.

27. The method of claim 19, wherein the ultra-high molecular weight or very-high molecular weight polyethylene material includes an additive such that the infrared-transmissive dome is generally translucent to visible wavelengths and provides greater than approximately sixty five percent transmission to infrared wavelengths within approximately eight to thirteen micrometers.

15. An infrared camera system, comprising:

a lens coupled to the infrared camera system;

an infrared-transmissive dome coupled to the infrared camera system; and

an image capture component configured to receive infrared energy passing through the infrared-transmissive dome and the lens and provide infrared thermal image data;

wherein;

the infrared-transmissive dome comprises a main body providing a hollow, hemispherical-shaped dome;

the main body made of an ultra-high molecular weight or a very-high molecular weight polyethylene material; and

the main body has a wall thickness from 0.005 inches to 0.012 inches and is configured to allow infrared energy transmittance greater than approximately sixty five percent through the main body to the lens for infrared thermal imaging in a wavelength range of approximately three to fourteen micrometers.

16. The infrared camera system of claim 15, comprising:

a processing component configured to control the image capture component and process the infrared thermal image data;

a memory component coupled to the processing component and configured to store the processed infrared thermal image data; and

a display component configured to display the processed infrared thermal image data;

wherein a ratio of the wall thickness to a diameter of the infrared-transmissive dome is approximately 0.004 or less and the the main body of the infrared-transmissive dome is self-supporting.

17. The infrared camera system of claim 15, wherein a peak-to-peak variation of the wall thickness is approximately 0.0001 inches or less over any contiguous area defined by a pi/16 solid angle, a variation of the wall thickness is approximately 0.001 inches or less for the main body, and a radius of curvature of the main body varies by approximately ten percent or less from a mean radius of curvature over any contiguous area defined by a pi/16 solid angle.

18. The infrared camera system of claim 15, wherein the ultra-high molecular weight polyethylene material and/or the very-high molecular weight polyethylene material includes an additive to provide ultraviolet protection, and wherein the infrared-transmissive dome is couplable to the lens so that the main body of the infrared-transmissive dome is spaced from an outer surface of the lens.