Compact emissivity and temperature measuring infrared detector

• US 20070152153A1
• Filed: 03/06/2007
• Published: 07/05/2007
• Est. Priority Date: 10/15/2004
• Status: Active Grant

• Current Assignee: Axient LLC
• Original Assignee: Millennium Engineering and Integration Company
• Inventors: Didomenico, John, Bevan, Edward, Gedridge, Robert, Briggs, Max
• Granted Patent: US 7,439,510 B2
• Time in Patent Office: Days
• US Class Current: 250/338.100
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 5/0003 for sensing the radiant heat transfer of samples, e.g. emittance meter
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/026 Control of working procedures of a pyrometer, other than calibration; Bandwidth calculation; Gain control
• CPC Class Codes: G01J 5/0265 Handheld, portable ear thermometers G01J5/049
• CPC Class Codes: G01J 5/53 Reference sources, e.g. standard lamps; Black bodies
• CPC Class Codes: G01J 5/602 using selective, monochromatic or bandpass filtering
• CPC Class Codes: G01J 5/80 Calibration using comparison with reference sources G01J5/52

Abstract

A hand-held, fleet deployable infrared camera with integrated hardware and software providing real time processing of infrared images. The camera senses variable temperature images over a selected object of interest and senses variable emissivities over the object. The camera also measures and corrects for reflected environmental radiation as well as corrections for the atmospheric path through which the object is viewed. A calibrated reference patch having known emissivity and reflectance is attached to an object of interest and viewed through the camera. The calibrated patch is used to provide correction for the environmental radiation reflected off the object. Once the environmental radiation correction is known, it can be used to correct measurements taken from the rest of the object of interest.

Claims

1. An emissivity detector comprising:

an infrared camera comprising;

(1) a plurality of infrared sensitive detector elements arranged as a two-dimensional array; and

(2) means for alternating the band of wavelength of infrared signals incident upon said detector elements;

a processing circuit, including a memory having a plurality of atmospheric models for selection stored therein, said atmospheric models being used to correct the atmospheric transmission path of infrared signals from an object of interest to said camera, said processing circuit being adapted to compute emissivity and/or temperature of said object of interest; and

a screen that is arranged to display an image representing said emissivity and/or temperature of said object of interest.

2. A method for measuring emissivity and temperature of an object, comprising:

providing a detector that receives energy in a plurality of wavelengths;

measuring the range between said object and said detector;

correcting the received energy for the atmospheric path along the range from the object to the detector;

decoupling reflected radiation from the radiation emitted by the object; and

calculating the temperature of the object.