Non-contacxt medical thermometer with distance sensing and compensation

Abstract

A non-contact medical thermometer is disclosed that includes an IR sensor assembly having an IR sensor for sensing IR radiation from a target, a distance sensor configured to determine a distance of the thermometer from the target, and a memory component operatively coupled at least to the IR sensor assembly and the distance sensor. The memory component contains predetermined compensation information that relates to predetermined temperatures of targets and to predetermined distances from at least one predetermined target. A microprocessor is operatively coupled to the memory component. The microprocessor is configured to perform temperature calculations based on the IR radiation from the target, the distance of the thermometer from the target, and the predetermined compensation information.

1 . A non-contact medical thermometer, comprising:
 an IR sensor assembly including an IR sensor for sensing IR radiation from a target;   a distance sensor configured to determine a distance of the thermometer from the target;   a memory component operatively coupled at least to the IR sensor assembly and the distance sensor, and containing predetermined compensation information that relates to predetermined temperatures of at least one predetermined target and predetermined distances from the at least one predetermined target; and   a microprocessor operatively coupled to at least the memory component, and configured to determine a compensated temperature based on at least the IR radiation from the target, the distance of the thermometer from the target, and the predetermined compensation information.   
     
     
         2 . The non-contact medical thermometer of  claim 1  wherein the predetermined compensation information further relates to predetermined oral and/or oral-equivalent temperatures. 
     
     
         3 . The non-contact medical thermometer of  claim 1  wherein the predetermined temperatures of the at least one predetermined target are based on clinical measurements of the predetermined target. 
     
     
         4 . The non-contact medical thermometer of  claim 1  wherein the at least one target is a forehead. 
     
     
         5 . The non-contact medical thermometer of  claim 3  wherein the predetermined compensation information is configured as a mathematical function. 
     
     
         6 . The non-contact medical thermometer of  claim 5  wherein the mathematical function is linear. 
     
     
         7 . The non-contact medical thermometer of  claim 5  wherein the mathematical function is T c =T t +A*d+B,  where T c  is the compensated temperature, T t  is a temperature of the target, where A and B are coefficients, and where d is the distance of the thermometer from the target. 
     
     
         8 . The non-contact medical thermometer of  claim 7  wherein A is approximately 0.05° F./cm. 
     
     
         9 . The non-contact medical thermometer of  claim 8  wherein B is approximately 0.1° F. 
     
     
         10 . The non-contact medical thermometer of  claim 7  wherein A is approximately 0.05° F./cm when d is less than or equal to approximately 15 cm, and wherein A is approximately 0.15° F./cm when d is greater than approximately 15 cm. 
     
     
         11 . The non-contact medical thermometer of  claim 10  wherein B is approximately 0.2° F. when d is less than or equal to approximately 15 cm, and wherein B is approximately 0.1° F. when d is greater than approximately 15 cm. 
     
     
         12 . The non-contact medical thermometer of  claim 5  wherein the mathematical function is quadratic. 
     
     
         13 . The non-contact medical thermometer of  claim 3  wherein the predetermined compensation information is configured as a look-up table. 
     
     
         14 . The non-contact medical thermometer of  claim 3  wherein the predetermined compensation information is configured as one or more offset values. 
     
     
         15 . The non-contact medical thermometer of  claim 14  wherein a first offset value is used for a first range of distances between the medical thermometer and the target and a second offset value is used for a second range of distances between the medical thermometer and the target. 
     
     
         16 . The non-contact medical thermometer of  claim 14  wherein the one or more offset values are between approximately 0.0° Fahrenheit and 5.0° Fahrenheit 
     
     
         17 . The non-contact medical thermometer of  claim 14  wherein the one or more offset values is a single offset value of approximately 0.1° Fahrenheit. 
     
     
         18 . The non-contact medical thermometer of  claim 3  wherein the predetermined compensation information further relates to a temperature of the IR sensor. 
     
     
         19 . The non-contact medical thermometer of  claim 3  wherein the predetermined compensation information further relates to a temperature of the ambient environment. 
     
     
         20 . The non-contact medical thermometer of  claim 1 ,
 wherein the distance sensor is configured to emit a radiation toward the target, capture at least a portion of the emitted radiation reflected from the target, and communicate a distance signal to the microprocessor, and   wherein the microprocessor is configured to determine a distance value corresponding to the distance between the thermometer and the target based on the distance signal and the characteristics of the reflected radiation.   
     
     
         21 . A method of determining a compensated temperature, comprising:
 holding an IR thermometer adjacent to a target, the thermometer including a memory containing predetermined compensation information relating to at least one predetermined distance between the IR thermometer and the target, and at least one predetermined temperature of the target; and   activating the IR thermometer to:
 measure a distance between the IR thermometer and the target; 
 measure a temperature of the target; and 
 determine a compensated temperature based on the predetermined compensation information, the distance measurement, and the target-temperature measurement. 
   
     
     
         22 . The method of  claim 21 , wherein the distance is measured using a distance sensor of the IR thermometer. 
     
     
         23 . The method of  claim 21 , wherein the temperature of the target is measured using an IR sensor of the IR thermometer. 
     
     
         24 . The method of  claim 21 , wherein the target is a forehead. 
     
     
         25 . The method of  claim 21  wherein the predetermined compensation information is configured as a mathematical function. 
     
     
         26 . The method of  claim 25  wherein the mathematical function is linear. 
     
     
         27 . The method of  claim 25  wherein the mathematical function is T c =T t +A*d+B, where T c  is the compensated temperature, T t  is a temperature of the target, where A and B are coefficients, and where d is the distance of the thermometer from the target. 
     
     
         28 . The method of  claim 27  wherein A is approximately 0.05° F./cm. 
     
     
         29 . The method of  claim 28  wherein B is approximately 0.1° F. 
     
     
         30 . The method of  claim 27  wherein A is approximately 0.05° F./cm when d is less than or equal to approximately 15 cm, and wherein A is approximately 0.15° F./cm when d is greater than approximately 15 cm. 
     
     
         31 . The method of  claim 30  wherein B is approximately 0.2° F. when d is less than or equal to approximately 15 cm, and wherein B is approximately 0.1° F. when d is greater than approximately 15 cm. 
     
     
         32 . The method of  claim 25  wherein the mathematical function is quadratic. 
     
     
         33 . The method of  claim 25  wherein the predetermined compensation information is configured as a look-up table. 
     
     
         34 . The method of  claim 25  wherein the predetermined compensation information is configured as one or more offset values. 
     
     
         35 . The method of  claim 34  wherein a first offset value is used for a first range of distances between the medical thermometer and the target and a second offset value is used for a second range of distances between the medical thermometer and the target. 
     
     
         36 . The method of  claim 34  wherein the one or more offset values are between approximately 0.0° Fahrenheit and 5.0° Fahrenheit 
     
     
         37 . The method of  claim 34  wherein the one or more offset values is a single offset value of approximately 0.1° Fahrenheit. 
     
     
         38 . The method of  claim 21  wherein the predetermined compensation information further relates to a temperature of the IR sensor. 
     
     
         39 . The method of  claim 21  wherein the predetermined compensation information further relates to a temperature of the ambient environment. 
     
     
         40 . A non-contact medical thermometer, comprising:
 an IR sensor assembly including an IR sensor capable of sensing IR radiation from a user's forehead;   a distance sensor configured to determine a distance of the thermometer from the user's forehead;   a memory component operatively coupled at least to the IR sensor assembly and the distance sensor, and containing at least one predetermined offset value that relates clinically predetermined temperatures to forehead temperature values at predetermined distances from the forehead and a temperature of the ambient environment or the thermometer; and   a microprocessor operatively coupled to at least the memory component, and configured to determine a compensated forehead temperature based on the IR radiation from the user's forehead, the distance of the thermometer from the user's forehead, and the predetermined offset value.   
     
     
         41 . The non-contact medical thermometer of  claim 40  wherein the one or more offset values are between approximately 0.0° Fahrenheit and 5.0° Fahrenheit 
     
     
         42 . The non-contact medical thermometer of  claim 40  wherein the one or more offset values is a single offset value of approximately 0.1° Fahrenheit.