U.S. patent application number 14/082345 was filed with the patent office on 2014-05-22 for non-contacxt medical thermometer with distance sensing and compensation.
This patent application is currently assigned to Kaz USA, Inc.. The applicant listed for this patent is Kaz USA, Inc.. Invention is credited to James Christopher Gorsich, Jiawei Hu, Charles Squires, Aleksan Yildizyan.
Application Number | 20140140368 14/082345 |
Document ID | / |
Family ID | 50349651 |
Filed Date | 2014-05-22 |
United States Patent
Application |
20140140368 |
Kind Code |
A1 |
Yildizyan; Aleksan ; et
al. |
May 22, 2014 |
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.
Inventors: |
Yildizyan; Aleksan;
(Waltham, MA) ; Hu; Jiawei; (Guangdong Province,
CN) ; Squires; Charles; (Waltham, MA) ;
Gorsich; James Christopher; (Los Angeles, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Kaz USA, Inc. |
Southborough |
MA |
US |
|
|
Assignee: |
Kaz USA, Inc.
Southborough
MA
|
Family ID: |
50349651 |
Appl. No.: |
14/082345 |
Filed: |
November 18, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61728015 |
Nov 19, 2012 |
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Current U.S.
Class: |
374/121 |
Current CPC
Class: |
G01J 5/0275 20130101;
G01J 5/0025 20130101; G01J 2005/0048 20130101 |
Class at
Publication: |
374/121 |
International
Class: |
G01J 5/02 20060101
G01J005/02 |
Claims
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.sub.c=T.sub.t+A*d+B, where T.sub.c is
the compensated temperature, T.sub.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.degree. F./cm.
9. The non-contact medical thermometer of claim 8 wherein B is
approximately 0.1.degree. F.
10. The non-contact medical thermometer of claim 7 wherein A is
approximately 0.05.degree. F./cm when d is less than or equal to
approximately 15 cm, and wherein A is approximately 0.15.degree.
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.degree. F. when d is less than or equal to
approximately 15 cm, and wherein B is approximately 0.1.degree. 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.degree.
Fahrenheit and 5.0.degree. 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.degree. 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.sub.c=T.sub.t+A*d+B, where T.sub.c is the compensated
temperature, T.sub.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.degree.
F./cm.
29. The method of claim 28 wherein B is approximately 0.1.degree.
F.
30. The method of claim 27 wherein A is approximately 0.05.degree.
F./cm when d is less than or equal to approximately 15 cm, and
wherein A is approximately 0.15.degree. F./cm when d is greater
than approximately 15 cm.
31. The method of claim 30 wherein B is approximately 0.2.degree.
F. when d is less than or equal to approximately 15 cm, and wherein
B is approximately 0.1.degree. 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.degree. Fahrenheit and 5.0.degree.
Fahrenheit
37. The method of claim 34 wherein the one or more offset values is
a single offset value of approximately 0.1.degree. 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.degree.
Fahrenheit and 5.0.degree. 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.degree. Fahrenheit.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional
application No. 61/728,015, filed Nov. 19, 2012, the disclosure of
which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] The present invention relate generally to devices for
measuring temperature, and more specifically, to non-contact
infrared thermometers for medical applications.
DESCRIPTION OF RELATED ART
[0003] A thermal radiation or infrared (IR) thermometer is a device
capable of measuring temperature without physically contacting the
object of measurement. Thus, such thermometers are often called
"non-contact" or "remote" thermometers. In an IR thermometer, the
temperature of an object is taken by detecting an intensity of the
IR radiation that is naturally emanated from the object's surface.
For objects between about 0.degree. C. and 100.degree. C., this
requires the use of IR sensors for detecting radiation having
wavelengths from approximately 3 to 40 micrometers. Typically, IR
radiation in this range is referred to as thermal radiation.
[0004] One example of an IR thermometer is an "instant ear" medical
thermometer, which is capable of making temperature measurements of
the tympanic membrane and surrounding tissues of the ear canal of a
human or animal. Instant ear thermometers are exemplified by U.S.
Pat. No. 4,797,840 to Fraden, which is incorporated by reference
herein in its entirety. Other examples include medical thermometers
for measuring surface skin temperatures (for example, a skin
surface temperature of the forehead) as exemplified by U.S. Pat.
No. 6,789,936 to Kraus et al., which is incorporated by reference
herein in its entirety.
[0005] In order to measure the surface temperature of an object
based on its IR radiation emissions, the IR radiation is detected
and converted into an electrical signal suitable for processing by
conventional electronic circuits. The task of detecting the IR
radiation is accomplished by an IR sensor or detector.
[0006] Conventional thermal IR sensors typically include a housing
with an infrared transparent window, or filter, and at least one
sensing element that is responsive to a thermal radiation energy
flux .PHI. emanating from an object's surface that passes through
the IR window of the IR sensor and onto the sensing element. The IR
sensor functions to generate an electric signal, which is
representative of the net IR flux .PHI. existing between the
sensing element and the object of measurement. The electrical
signal can be related to the object's temperature by appropriate
data processing.
[0007] In practice, users of medical thermometers are often
concerned with determining a temperature of a subject (e.g., a
person or animal) that an IR thermometer may be ill-suited to
measure directly. Accordingly, some non-contact medical
thermometers are designed to determine a temperature of a
particular body part of a person based on measurements of a
different body part. For example, there exist non-contact IR
thermometers for determining a temperature of a subject's mouth
(oral temperature) based on a measurement of a temperature of that
subject's forehead. This determination is typically performed using
a predetermined compensation function and/or a predetermined
look-up table that has been determined based on clinically
determined relationships between measured temperatures of a body
part, e.g., a subject's mouth, and temperatures of a different body
part, e.g., a subject's forehead.
[0008] Temperature readings produced by IR thermometers are
somewhat sensitive to the distance between the IR sensor and a body
part. Accordingly, IR thermometers that are capable of determining
the distance between the IR sensor and a target may use this
distance information to determine temperatures with greater
accuracy than IR thermometers without these capabilities. For
example, certain IR thermometers are designed to optimally measure
the temperature of a body part when the IR thermometer is located a
predetermined distance away from that object. U.S. Pat. No.
7,810,992 to Chen et al., which is herein incorporated by reference
in its entirety, discloses an IR thermometer that includes a
radiation emitter and receiver device. The radiation emitter and
receiver device is capable of determining distance between the IR
sensor and a target by: (1) emitting radiation that reflects off of
a target; (2) receiving the reflected radiation; and (3)
determining whether the distance is within a predetermined distance
range based on the characteristics of the reflected radiation. In
use, this IR thermometer performs a distance-measurement routine
whereby it may determine when the IR thermometer is located within
a predetermined distance range. Upon establishing that the IR
thermometer is positioned within the predetermined distance range,
the IR thermometer may then measure the temperature of the
target.
[0009] While such techniques are capable of increasing the accuracy
of temperature measurements, these techniques require the
additional tasks of determining the IR thermometer's position and
maintaining the thermometer at that position while the temperature
is determined. These tasks are cumbersome and time consuming.
Moreover, these tasks often result in user error, which may offset
improvements in accuracy that such IR thermometers may otherwise
provide. Accordingly, it would be of additional benefit to increase
the accuracy of IR thermometers without requiring that the IR
thermometer be positioned and maintained at a predetermined
distance from the target.
SUMMARY OF THE INVENTION
[0010] A non-contact IR thermometer according to various
embodiments of the present invention includes, among other things,
an IR sensor, a distance sensor, a microprocessor, a memory
configured to communicate with the microprocessor, and a user
interface device configured to receive inputs from the
microprocessor. The memory includes compensation information, e.g.,
a look-up table or mathematical equation that may be used to
determine a compensated temperature of a body part based on a
measurement of the same or another body part. For example, the
compensation information may be used to determine a compensated
temperature of a forehead based on a measured temperature of a
forehead. Or, the compensation information may be used to determine
a compensated oral or oral-equivalent temperature based on a
measured temperature of a forehead. The IR thermometer may be
configured to simultaneously or in sequence measure a temperature
of the target object, the ambient temperature, or temperature of
the thermometer, and a distance between the IR thermometer and the
target. The microprocessor may use these values and the
compensation information to determine a compensated temperature and
communicate this temperature to the user interface device, which
may further communicate the compensated temperature to a user.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The foregoing and other features of the present invention
will be more readily apparent from the following detailed
description and drawing of illustrative embodiments of the
invention in which:
[0012] FIG. 1 is a block diagram representative of an embodiment of
the present invention; and
[0013] FIG. 2 is a flow chart showing the method for compensated
temperature determination in accordance with an embodiment of the
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] A remote IR thermometer is disclosed that includes, among
other things, an IR sensor package or assembly having at least an
IR sensor and a sensor for sensing the temperature of the IR
sensor, a radiation emitter and receiver device, a microprocessor,
a memory containing compensation information configured to
communicate with the microprocessor, and a user interface device
configured to receive inputs from the microprocessor. For the
purpose of illustrating principles in accordance with various
embodiments of the present invention, several non-limiting examples
of the various embodiments are described below. Accordingly, the
scope of the invention should be understood to be defined only by
the scope of the claims and their equivalents, and not limited by
the example embodiments.
[0015] FIG. 1 is a block diagram illustrating an embodiment of the
IR thermometer 10 of the present invention. This embodiment
includes an IR sensor package/assembly 12, distance sensor 14, a
microprocessor 16, memory 18, user interface device 20, and housing
22. Housing 22 contains each of the other components, and
additionally includes at least a button and a circuit board with an
electronic circuit and a power supply.
[0016] IR sensor package/assembly 12 includes an IR sensor and, in
some embodiments, a temperature sensor for sensing the temperature
of the IR sensor and/or the temperature of the ambient environment.
The IR sensor is configured to capture thermal radiation emanating
from a target object or target body part, e.g., a subject's
forehead, armpit, ear drum, etc., which is converted into an
electrical temperature signal and communicated, along with a signal
regarding the temperature of the IR sensor as measured by the
temperature sensor, to microprocessor 16, as is known in the art.
Distance sensor 14 is configured to emit radiation from IR
thermometer 10 and to capture at least a portion of the emitted
radiation reflected from the target, which is converted into an
electrical distance signal and communicated to microprocessor 16.
Microprocessor 16 is configured to, among other things, determine a
temperature value of the target based on the signal from IR sensor
package/assembly 12, determine an ambient environment or
thermometer temperature, and to determine a distance value
corresponding to the distance between IR thermometer 10 and the
target using a correlation routine based on the signal from
distance sensor 14 and the characteristics of the reflected
radiation. In various embodiments, the temperature signal, distance
signal, temperature value, distance value, or any combination
thereof may be stored in memory 18.
[0017] Memory 18 includes therein predetermined compensation
information. This predetermined compensation information may be
empirically predetermined by performing clinical tests. These
clinical tests may relate the detected temperature of a target
(e.g., forehead), the distance of the IR thermometer from the
target, as well as the actual temperature of the target and the
ambient environment or thermometer temperature. These clinical
tests may further relate the temperature of the target, either the
detected temperature, the actual temperature, or both, to, e.g., an
actual oral or oral-equivalent temperature. Accordingly, target
temperatures of various subjects having oral temperatures between,
e.g., 94.degree. Fahrenheit to 108.degree. Fahrenheit, may be
measured using an IR thermometer at various known distances from
the targets, e.g., from 0 centimeters (i.e., thermometer contacts
target) to 1 meter, in increments of, e.g., 1 centimeter, 5
centimeters, or 10 centimeters. In some embodiments, the range of
distances corresponds to a range of distances over which IR
thermometer 10 may be operational. Additionally, these measurements
may be conducted in environments having various ambient
temperatures between, e.g., 60.degree. Fahrenheit to 90.degree.
Fahrenheit. These data may be used to create compensation
information, such as a look-up table or mathematical function,
whereby a compensated temperature of the target may subsequently be
determined from a measured distance value, e.g., using distance
sensor 14, a measured target temperature value, e.g., using IR
sensor package or assembly 12, and, in some embodiments, an ambient
environment temperature value and/or thermometer temperature value.
In other embodiments, data relating to actual oral or
oral-equivalent temperatures may be further used to create the
compensation information, whereby a compensated oral or compensated
oral-equivalent temperature may be determined from a measured
distance value, a measured target temperature value, and, in some
embodiments, an ambient environment temperature value and/or
thermometer temperature value.
[0018] For example, where d is defined as a distance between the
target and IR thermometer 10, the predetermined compensation
information for obtaining a compensated temperature in degrees
Fahrenheit may be a linear function or functions defined by the
following relationships:
Compensated Temperature=Target Temperature+A*d+B
Or
[0019] Compensated Temperature=Target Temperature+C*d+D {for
0<d.ltoreq.Y}, and
Compensated Temperature=Target Temperature+E*d+F {for
Y<d.ltoreq.Z},
where A, C, and E are coefficients having dimensions of
Temperature/Length; B, D and F are coefficients having dimensions
of Temperature; and Y and Z are distances from the target. Values
of A, B, C, D, E, F, Y, and Z may be determined empirically from
clinical tests. For purposes of illustration and not limitation,
the following exemplary and approximate values for the coefficients
and distances are provided: A=0.05, B=0.1, C=0.05, D=0.2, E=0.15,
F=0.1, Y=15, and Z=30. However, as will be recognized by persons
having ordinary skill in the art, other values for each coefficient
and distance may be used depending on various design features and
aspects of an IR thermometer 10.
[0020] It is also possible for the mathematical function to be of a
higher degree or order, for example, a mathematical function that
is non-linear with respect to the measured distance to obtain the
compensated temperature, such as the following quadratic
equation:
Compensated Temperature=Target Temperature+G*d.sup.2-H*d+L
Where G, H, and L are coefficients determined from the clinical
tests. For purposes of illustration and not limitation, the
following exemplary and approximate values for the coefficients are
provided: G=0.001, H=0.15, and L=0.1. However, as will be
recognized by persons having ordinary skill in the art, other
values for each coefficient may be used depending on various design
features and aspects of an IR thermometer 10.
[0021] The compensation information may alternatively be provided
as various offset values, whereby, for each distance increment or
range of distances from the target surface, there is a
corresponding offset value. In various embodiments, these offsets
may be fixed for each of the distance increments or range of
distances from the target surface. For example, in various
embodiments, the offset value may be, e.g., any one of 0.1.degree.
F., 0.2.degree. F., or 0.5.degree. F. over a range of distances
from the target surface such as 0 cm to 5 cm, 0 cm to 20 cm, or 5
cm to 30 cm. For example, in one embodiment, the offset value may
be 0.0.degree. F. from 0.0 cm to 0.1 cm, 0.1.degree. F. from 0.1 cm
to 3.0 cm, 0.2.degree. F. from 3.0 cm to 15 cm, and 0.5.degree. F.
from 15.1 cm to 30 cm. Alternatively, the compensation information
may be in the form of a single, e.g., "best-fit," offset value that
may be used to determine a compensated temperature from any of the
target temperatures over a distance range, either the entire
distance range recited above or a portion thereof. For example, the
"best-fit" offset value may be, e.g., any one of 0.1.degree. F.,
0.2.degree. F., or 0.5.degree. F. For example, in one embodiment,
the offset value may be 0.1.degree. F. over the distance range from
0.0 cm to 10 cm, and 0.0.degree. F. for greater distances. In other
embodiments, the offset value may be 0.1.degree. F. over the
distance range from 0.0 cm to 30 cm, and 0.0.degree. F. for
distances greater than 30 cm.
[0022] In other embodiments, the compensation information may be in
the form of a look-up table, which may be devised from
predetermined information collected during clinical tests, such as
actual target temperature, measured target temperature, ambient
environment and/or thermometer temperature, and distance
measurements, such that, subsequently, a compensated temperature
may be determined by identifying in the look-up table those values
that best correspond to the measured distance and measured
target-temperature values. In the event of an imperfect match
between the measured values and the table values, the closest table
values may be used, or, additional values interpolated from the
table values may be used. In other embodiments, the compensation
information may include a combination of more than one of the
approaches (e.g., mathematical function, offset value, look-up
table) described above
[0023] Further, as noted above, the ambient environment temperature
value and/or thermometer temperature value may be used in
generating compensation information. It may be beneficial to
include these values as factors in the compensation information
because these values may increase the accuracy of a compensated
temperature calculated based on the compensation information. For
example, the above discussed mathematical functions may be modified
based on ambient environment temperature and/or thermometer
temperature. For example, a first "best fit" offset value (e.g.,
0.1.degree. F.) may be used when the ambient temperature is within
a first range of temperatures (e.g., 60.degree. F. to 75.degree.
F.), and a second "best fit" offset value (e.g., 0.2.degree. F.)
may be used when the ambient temperature is within a second range
of temperatures (e.g., 75.degree. F. and 90.degree. F.).
[0024] Microprocessor 16 is configured to use a temperature value
corresponding to a target and a distance value corresponding to the
distance between IR thermometer 10 and the target to determine a
compensated temperature using the predetermined compensation
information stored in memory 18. In some embodiments,
Microprocessor 16 may be further configured to use an ambient
and/or thermometer temperature in this determination. In some
embodiments, the predetermined compensation information may be
based in part on ambient and/or thermometer temperature. In those
embodiments where the predetermined compensation information
includes predetermined information concerning oral or
oral-equivalent temperatures, Microprocessor 16 may be further
configured to determine a compensated temperature corresponding to
an oral or oral-equivalent temperature.
[0025] Microprocessor 16 may further store one or more compensated
temperature values in memory 18 and communicate it to user
interface device 20. In various embodiments, the microprocessor is
further configured to interpolate additional values from any values
stored in a look-up table in memory 18. User interface device 20 is
configured to communicate the compensated temperature value to a
user. For example, user interface device 20 may include, e.g., a
display capable of displaying at least the compensated temperature
value and/or a speaker configured to make an audible sound such as
speaking the compensated temperature value or sounding an
alarm.
[0026] Referring to FIG. 2, the flow chart shows an embodiment of a
method for determining a compensated temperature based on a
measured temperature of a target on that subject, e.g., that
subject's forehead. In step 102, the process for determining the
compensated temperature starts, e.g., by the user depressing a
start button to, e.g., activate IR thermometer 10. In step 104,
distance sensor 14 is used to emit radiation and capture reflected
radiation from a target to generate a distance signal, which is
communicated to microprocessor 16. Microprocessor 16 determines a
distance value from the distance signal, which microprocessor 16
may store in memory 18. In step 106, IR sensor package/assembly 12
is used to capture thermal radiation emanating from the target to
generate a temperature signal, and, optionally, to capture an
ambient and/or thermometer temperature, which are communicated to
microprocessor 16. Microprocessor 16 determines a temperature value
from the temperature signal, which microprocessor 16 may store in
memory 18. In optional step 108, which is performed when the
predetermined compensation information includes a look-up table,
microprocessor 16 determines a relationship between the distance
value and the temperature values using predetermined compensation
information. In step 110 microprocessor 16 determines a compensated
temperature value based on the predetermined compensation
information. In step 112, microprocessor 16 stores the compensated
temperature in memory 18. In step 114, the compensated temperature
value is communicated using user interface 20.
[0027] While the various embodiments of the invention have been
particularly shown and described, it will be understood by those
skilled in the art that various changes in form and details may be
made therein without departing from the spirit and scope of the
invention. Accordingly, these embodiments are non-limiting examples
of the invention and the invention should be understood to be
defined only by the scope of the claims and their equivalents.
* * * * *