U.S. patent application number 13/375750 was filed with the patent office on 2012-03-29 for apparatus and method for controlling the temperature of a black body.
This patent application is currently assigned to KOREA BASIC SCIENCE INSTITUTE. Invention is credited to Ki Soo Chang, Geon Hee Kim, Hyo Sik Kim, Jeong Min Lee, Moon Seop Yang, Sun Choel Yang.
Application Number | 20120073308 13/375750 |
Document ID | / |
Family ID | 43970564 |
Filed Date | 2012-03-29 |
United States Patent
Application |
20120073308 |
Kind Code |
A1 |
Kim; Geon Hee ; et
al. |
March 29, 2012 |
APPARATUS AND METHOD FOR CONTROLLING THE TEMPERATURE OF A BLACK
BODY
Abstract
Provided is an apparatus for controlling temperature of a black
body. The apparatus includes a black body emitting radiant energy
of infrared rays; a first Peltier element adjacent to the black
body, the first Peltier element having a 1a surface and a 1b
surface that selectively emit or absorb heat; a copper plate
adjacent to the 1b surface; a second Peltier element adjacent to
the 2b surface, the second Peltier element having a 2a surface and
a 2b surface that selectively emit or absorb heat; a heat transfer
member comprising a bent surface adjacent to the 2a surface, and an
arm extending toward both ends of the black body to be adjacent to
the both ends of the black body and a control unit controlling the
2a surface to emit heat when the 1a surface emits heat, and the 2a
surface to absorb heat when the 1a surface absorbs heat.
Inventors: |
Kim; Geon Hee; (Daejeon,
KR) ; Lee; Jeong Min; (Daejeon, KR) ; Yang;
Sun Choel; (Daejeon, KR) ; Chang; Ki Soo;
(Daejeon, KR) ; Kim; Hyo Sik; (Daejeon, KR)
; Yang; Moon Seop; (Daegu, KR) |
Assignee: |
KOREA BASIC SCIENCE
INSTITUTE
Daejeon
KR
|
Family ID: |
43970564 |
Appl. No.: |
13/375750 |
Filed: |
November 5, 2010 |
PCT Filed: |
November 5, 2010 |
PCT NO: |
PCT/KR2010/007779 |
371 Date: |
December 1, 2011 |
Current U.S.
Class: |
62/3.2 |
Current CPC
Class: |
G05D 23/1919 20130101;
G05D 23/27 20130101; G01J 5/522 20130101 |
Class at
Publication: |
62/3.2 |
International
Class: |
F25B 21/02 20060101
F25B021/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 6, 2009 |
KR |
10-2009-0106798 |
Claims
1. An apparatus for controlling temperature of a black body,
comprising: a black body emitting radiant energy of infrared rays;
a first Peltier element adjacent to the black body, the first
Peltier element having a 1a surface and a 1b surface that
selectively emit or absorb heat; a copper plate adjacent to the 1b
surface; a second Peltier element adjacent to the 2b surface, the
second Peltier element having a 2a surface and a 2b surface that
selectively emit or absorb heat; a heat transfer member comprising
a bent surface adjacent to the 2a surface, and an arm extending
toward both ends of the black body to be adjacent to the both ends
of the black body; and a control unit controlling the 2a surface to
emit heat simultaneously when the 1a surface emits heat, and the 2a
surface to absorb heat simultaneously when the 1a surface absorbs
heat, wherein the second Peltier element has a through hole at the
center thereof, and the apparatus further comprises a heat-emitting
member contacting the copper plate to exhaust heat generated in the
copper plate.
2. The apparatus of claim 1, wherein when the black body is cooled,
the temperature of the 1a surface is lower than the temperature of
the 2a surface.
3. The apparatus of claim 1, wherein when the black body is heated,
the temperature of the 1a surface is higher than the temperature of
the 2a surface.
4. (canceled)
5. The apparatus of claim 1, wherein the heat-emitting member
comprises a heat-emitting plate connected to the copper plate,
which performs heat exchange in a water-cooling manner or in an
air-cooling manner.
6. A method for controlling temperature of a black body using the
apparatus of claim 1 comprising: measuring temperature of the black
body emitting radiant energy of infrared rays; determining whether
the measured temperature is higher or lower than a predetermined
temperature; and emitting heat from a 1a surface adjacent to the
black body and a 2a surface of a second Peltier element adjacent to
a heat transfer member comprising an arm adjacent to both ends of
the black body 2 when the measured temperature is lower than the
predetermined temperature, and absorbing heat into the 1a surface
and the 2a surface adjacent to the black body when the measured
temperature is higher than the predetermined temperature.
7. The method of claim 6, wherein when heat is emitted from the 1a
surface, the temperature of the 1a surface is lower than the
temperature of the 2a surface, and when heat is absorbed into the
1a surface, the temperature of the 1a surface is higher than the
temperature of the 2a surface.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an apparatus and method for
controlling the temperature of a black body, and more particularly,
to an apparatus and method for controlling the temperature of a
black body using a Peltier element.
[0002] Generally, a black body is used for test and temperature
correction of a thermal imaging camera. Since the emissivity of a
black body is about 1, it emits almost 100% of its energy. The
thermal imaging camera includes a detector for sensing a black
body. The detector is formed of a sensor array with a plurality of
detecting sensors. For an example, one detector is formed of a
sensor array including 76,800 sensors, i.e., 320 sensors
horizontally and 240 sensors vertically. Such an array is called
Focal Plane Array (FPA).
[0003] However, each of sensors that constitute a sensor array
shows a little difference in its performance due to errors during a
manufacturing process. Particularly, this phenomenon, unevenness of
performance level, is especially critical for detectors in thermal
imaging cameras. Thus, when an electronic circuit is assembled and
images are generated, it is hard to recognize the images because
the sensors have such a great difference in their performance
capability. A device is needed to compensate for different
performances of sensors in the thermal imaging camera using ambient
temperature and the temperature of black body source such that such
characteristics show almost uniform performance through
compensation and correction in advance.
[0004] In domestic military and specialized industry fields,
military thermal imaging apparatuses and medical thermo-graphic
imaging apparatuses are generally imported, which are technologies
that are not common in private sectors of industry. In the field of
software adequate for user environments, standard measuring and
analyzing devices for thermal image apparatuses have not been
developed at all.
[0005] In the global market, there are SBIR from the U.S., CI from
Israel, MICRON from EU produce black bodies as manufacturers of
black bodies, and there are Chinese manufacturers that produce
low-price products. SBIR is the company that has the most advanced
technology among them, developing and selling various black bodies.
However, even SBIR is not adopting a black body with vacuum package
for fine temperature stabilization.
[0006] Since the technology for temperature correction is not
actively developed neither domestically nor internationally, errors
cannot be corrected, causing miscalculation to the measured values.
Accordingly, a technology for temperature correction and
performance evaluation of a thermal imaging camera that changes a
difference in infrared radiant energy into an image visible to
human eyes needs to be developed.
SUMMARY OF THE INVENTION
[0007] The present invention provides an apparatus and method for
controlling the temperature of a black body in which temperature
distribution is uniform.
[0008] The present invention also provides an apparatus and method
for controlling the temperature of a black body by changing the
temperature of the black body into a desired temperature and
photographing the black body using a thermal imaging camera.
[0009] In accordance with an exemplary embodiment, an apparatus for
controlling temperature of a black body includes: a black body
emitting radiant energy of infrared rays; a first Peltier element
adjacent to the black body, the first Peltier element having a 1a
surface and a 1b surface that selectively emit or absorb heat; a
copper plate adjacent to the 1b surface; a second Peltier element
adjacent to a 2b surface, The second Peltier element having a 2a
surface and the 2b surface that selectively emit or absorb heat; a
heat transfer member comprising a bent surface adjacent to the 2a
surface, and an arm extending toward both ends of the black body to
be adjacent to the both ends of the black body; and a control unit
controlling the 2a surface to emit heat simultaneously when the 1a
surface emits heat, and the 2a surface to absorb heat
simultaneously when the 1a surface absorbs heat.
[0010] Particularly, when the black body is cooled, the temperature
of the 1a surface may be lower than the temperature of the 2a
surface.
[0011] And, when the black body is heated, the temperature of the
1a surface may be higher than the temperature of the 2a
surface.
[0012] Further, the second Peltier element has a through hole at
the center thereof, and the apparatus further comprises a
heat-emitting member contacting the copper plate to exhaust heat
generated in the copper plate.
[0013] The heat-emitting member may include a heat-emitting plate
connected to the copper plate, which performs heat exchange in a
water-cooling manner or in an air-cooling manner.
[0014] In accordance with another exemplary embodiment, a method
for controlling temperature of a black body includes: measuring
temperature of the black body emitting radiant energy of infrared
rays; determining whether the measured temperature is higher or
lower than a predetermined temperature; and emitting heat from a 1a
surface adjacent to the black body and a 2a surface of a second
Peltier element adjacent to a heat transfer member comprising an
arm adjacent to both ends of the black body 2 when the measured
temperature is lower than the predetermined temperature, and
absorbing heat into the 1a surface and the 2a surface adjacent to
the black body when the measured temperature is higher than the
predetermined temperature.
[0015] When heat is emitted from the 1a surface, the temperature of
the 1a surface may be lower than the temperature of the 2a surface,
and when heat is absorbed into the 1a surface, the temperature of
the 1a surface may be higher than the temperature of the 2a
surface.
[0016] In accordance with embodiments, an apparatus and method for
controlling the temperature of a black body can be applied to
apparatuses for evaluating performance and reliability of a thermal
imaging camera for monitoring a forward area, testers for
performance of a semiconductor wiper block, non-destructive
thermo-conductive analysis in the non-destructive field, medical
equipment for diagnosing body heat, and, and satellite mounted
optical systems for infrared rays, thereby securing calibration
technology.
[0017] Also, a dual Peltier element structure is used for heating
and cooling of a black body, increasing the cooling efficiency. A
temperature compensation plate near both ends of a black body is
connected to the dual Peltier element structure to allow the black
body to have uniform temperature distribution and thus reduce a
deviation between temperatures of the center and the edge of the
black body, thereby efficiently heating and cooling the dual
Peltier element structure together with the black body and
miniaturizing them.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Exemplary embodiments can be understood in more detail from
the following description taken in conjunction with the
accompanying drawings, in which:
[0019] FIG. 1 is a view illustrating an arrangement of Peltier
elements according to an embodiment of the present invention;
[0020] FIG. 2 is a view illustrating an apparatus for controlling
the temperature of a black body in an air-cooling manner according
to an embodiment of the present invention;
[0021] FIG. 3 is a view illustrating an apparatus for controlling
the temperature of a black body in a water-cooling manner according
to an embodiment of the present invention; and
[0022] FIG. 4 is a flowchart illustrating a method for controlling
the temperature of a black body according to an embodiment of the
present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Hereinafter, exemplary embodiments of the present invention
will be described in detail with reference to the accompanying
drawings.
[0024] FIG. 1 is a view illustrating an arrangement of Peltier
elements according to an embodiment of the present invention.
However, detailed configuration including a through hole is not
shown in FIG. 1.
[0025] Generally, Peltier elements include thermoelectric elements
that are disposed in parallel to each other and include a
semiconductor with N-type impurity ions and a semiconductor with
P-type impurity ions. Electrodes formed of copper plate may be
coupled to an upper side and a lower side of the thermoelectric
element. Also, a ceramic substrate may be attached to surround the
electrodes.
[0026] The Peltier elements generate a Peltier effect in which an
upper portion is cooled and a lower portion is heated because heat
is emitted from the upper portion to the lower portion while
electrons of an N-type semiconductor or holes of a P-type
semiconductor move from an upper electrode to a lower electrode by
application of a current to a junction. The Peltier effect, which
is one of electrical phenomena, refers to a phenomenon in which
when a current is applied to a junction between two different types
of metal, heat is generated or absorbed at the junction.
[0027] Accordingly, when a current is applied to a Peltier element,
one side of the Peltier forms a heat-absorbing surface of a low
temperature, and the other side thereof forms a heat-emitting
surface of a high temperature. If a current is applied in the
reverse direction, the heat-absorbing surface and the heat-emitting
surface may be switched.
[0028] As shown in FIG. 1, a first Peltier element 10 and a second
Peltier element 20 may be arranged, and a copper plate 30 may be
disposed between the first Peltier element 10 and the second
Peltier element 20.
[0029] The first Peltier element 10 may have a 1a surface 12 and a
1b surface 14 that can selectively emit or absorb heat, and the
second Peltier element 20 may have a 2a surface 22 and a 2b surface
24 that can selectively emit or absorb heat.
[0030] Particularly, the 1a surface 12, the 1b surface 14, the 2b
surface 24, and the 2a surface 22 may be arranged sequentially from
right to left. When an exothermic reaction occurs in the 1a surface
12, an exothermic reaction may also occur in the 2a surface 22. On
the other hand, when an endothermic reaction occurs in the 1a
surface 12, an endothermic reaction may also occur in the 2a
surface 22.
[0031] FIG. 2 is a view illustrating an apparatus for controlling
the temperature of a black body in an air-cooling manner according
to an embodiment of the present invention.
[0032] An apparatus for controlling the temperature of a black body
according to an embodiment of the present invention may include a
black body 2 emitting radiant energy of infrared rays, a first
Peltier element 10 adjacent to the black body 2, a copper plate 30
adjacent to the 1b surface 14, a second Peltier element 20 adjacent
to the copper plate 30, and a heat transfer member 40 adjacent to
the 2a surface 22.
[0033] The apparatus for controlling the temperature of the black
body may further include a control unit 50. The control unit may
control the 2a surface 22 to emit heat simultaneously when the 1a
surface 12 emits heat, and control the 2a surface 22 to absorb
simultaneously when the 1a surface 12 absorbs heat. In other words,
the control unit 50 may control the 2b surface 24 to emit heat
simultaneously when the 1b surface 14 emits heat and control the 2b
surface 24 to absorb heat simultaneously when the 1b surface 14
absorbs heat.
[0034] The heat transfer member 40 may include a bent surface
adjacent to the 2a surface 22, and an arm 44 connected to the bent
surface 42. The arm 44 may extend toward to both ends of the black
body 2 to deliver heat received from the surface 2a and the bent
surface 42 to the black body 2.
[0035] A through hole 26 may be formed in the center of the second
Peltier element 20. A heat-emitting member 27 may be disposed in
the through hole 26. The heat-emitting member 27 may contact the
copper plate 30 to emit heat generated from the copper plate 30.
When the temperature of the copper plate 30 is higher than the
outside temperature, the heat-emitting member 27 may be heated to
exhaust heat of the copper plate 30 to the outside. When the
temperature of the copper plate 30 is lower than the outside
temperature, the heat-emitting member 27 may be cooled to supply
heat to the copper plate 30.
[0036] As shown in FIG. 2, a heat-emitting plate 28 may be disposed
at one end of the heat-emitting member 27 to exchange heat with the
outside. The heat-emitting plate 28 may include a plurality of
cooling fins. A fan 60 may be provided in the heat-emitting plate
28 to efficiently perform heat exchange in an air-cooling
manner.
[0037] Since the heat exchange by the heat-emitting plate 28 and
the fan 60 is performed similarly to the principle of a heat
exchanger, a detailed description thereof will be omitted
herein.
[0038] The control unit 50 may control the operation of the fan 60
to improve the efficiency of heat exchange performed by the
heat-emitting plate 28. For example, when the temperature of the
heat-emitting plate 28 is higher or lower than normal temperature,
the fan 60 may be operated to facilitate the heat exchange.
[0039] The control unit 50 may heat or cool the black body 2 by
controlling the direction of a current flowing in the first Peltier
element 10 and the second Peltier element 20, and may exchange heat
delivered to the copper plate 30 with the outside by controlling
the fan 60.
[0040] FIG. 3 is a view illustrating an apparatus for controlling
the temperature of a black body in a water-cooling manner according
to an embodiment of the present invention. The apparatus shown in
FIG. 3 differs from that of FIG. 2 in that heat exchange is
performed using water, and other features thereof are similar to
those of FIG. 2. Therefore, the following description of the
apparatus of FIG. 3 will be focused on the difference from that of
FIG. 2.
[0041] A receiving unit 62 may be disposed adjacent to the
heat-emitting plate 28. The receiving unit 62 may receive water and
allow water to circulate for heat exchange. Since the heat exchange
by the heat-emitting plate 28 and the receiving unit 62 is
performed similarly to the principle of a heat exchanger, a
detailed description thereof will be omitted herein.
[0042] Unlike that of FIG. 2, the control unit 50 may control the
flow rate and the flow amount of cooling water in the receiving
unit 62. When the temperature of the heat-emitting plate 28 is
higher or lower than normal temperature, or when heat exchange
needs to be promptly performed, the control unit 50 may control the
flow rate of water such that heat exchange can be smoothly
performed between the receiving unit 62 and the heat-emitting plate
28.
[0043] FIG. 4 is a flowchart illustrating a method for controlling
the temperature of a black body according to an embodiment of the
present invention. Hereinafter, a detailed description of the
method will be made with reference to FIG. 4.
[0044] It is difficult for sensors installed in a thermal imaging
camera to measure exact values due to the characteristics of
sensors or external factors. Accordingly, correction or
compensation may be performed on the sensors by measuring energy
emitted from the black body while varying the temperature of the
black body.
[0045] Temperature to be measured by a thermal imaging camera is
set. In this case, if there are a variety of temperatures to be
measured by the thermal imaging camera, the predetermined
temperature may be diversified. Generally, when correcting the
thermal imaging camera, the predetermined temperature may be
selected in plurality from a temperature range of about -10.degree.
C. to about 70.degree. C.
[0046] The temperature of the black body 2 may be measure
(S10).
[0047] The measured temperature of the black body 2 may be compared
with the predetermined temperature (S20).
[0048] If the measured temperature is higher than the predetermined
temperature (S30), the temperature of the black body 2 may need to
be cooled to the predetermined temperature (S42). Accordingly, the
control unit 50 may apply a current to the first Peltier element 10
and the second Peltier element 20 such that the 1a surface 12 of
the first Peltier element 10 and the 2a surface 22 of the second
Peltier element 20 serve as a heat-absorbing surface. In this case,
since the 1b surface 14 of the first Peltier element 10 and the 2b
surface 24 of the second Peltier element 20 serve as a
heat-emitting surface, the temperature thereof may rise.
[0049] Since the temperature T1 of the 1a surface 12 decreases, the
black body 2 adjacent to the 1a surface 12 may be cooled. In this
case, the temperature at the central portion of the black body 2
may become lower than the temperature at both ends of the black
body 2. In other words, the temperature distribution of the black
body 2 may form a two-dimensional curve in which the temperature is
the more low at the center thereof. More convection of external air
may occur at both ends of the black body 2 and both ends of the 1a
surface 12 than at their central portions, and the cooling effect
is not uniform on the whole of the 1a surface 12 in practice, not
in theory.
[0050] The temperature T2 of the 2a surface 22 may be set lower
than the temperature T1 of the 1a surface 12 (S44). The temperature
T2 may be delivered to the bent surface 42 adjacent to the 2a
surface 22, and the bent surface 42 may be connected to the arm 44
such that heat transfer is possible. Accordingly, temperature T2
may be substantially delivered to the arm 44. Since the arm 44 is
adjacent to the both ends of the black body 2, the both ends of the
black body 2 may be cooled by the arm 44. Furthermore, since the
temperature T2 is lower than the temperature T1, the both ends of
the black body 2 may be cooled to a temperature lower than the
temperature T1 of the 1a surface 12 by the temperature T2 of the 2a
surface 22. Accordingly, the temperature of the black body 2 may be
corrected such that the temperature is uniform at the both ends and
the central portion of the black body 2. On the other hand, heat
may be generated from the 1b surface 14 and the 2b surface 24. The
generated heat may be delivered to the copper plate 30, and then
may be delivered from the copper plate 30 to the heat-emitting
plate 28 connected to the heat-emitting member 27, allowing heat to
be exchanged by the fan 60 or the receiving unit 62 in an
air-cooling manner or a water-cooling manner.
[0051] If heat is not emitted to the outside by the copper plate
30, the black body 2 may not be cooled to a desired temperature due
to heat generated in the 1b surface 14 and the 2b surface 24.
Although not shown in the drawings, the first Peltier element 10
and the second Peltier element 20 may be airtightly disposed in one
case, and heat by the 1b surface 14 and the 2b surface 24 may
affect the 1a surface 12 and the 2a surface 22.
[0052] When the measured temperature is lower than the
predetermined temperature, the black body 2 may need to be heated
to the predetermined temperature (S52). Accordingly, the control
unit 50 may apply a current to the first Peltier element 10 and the
second Peltier element 20 such that the 1a surface 12 of the first
Peltier element 10 and the 2a surface 22 of the second Peltier
element 20 serve as a heat-emitting surface. In this case, since
the 1b surface 14 of the first Peltier element 10 and the 2b
surface 24 of the second Peltier element 20 serve as a
heat-absorbing surface, the temperature thereof may fall.
[0053] Since the temperature T1 of the 1a surface 12 increases, the
black body 2 adjacent to the 1a surface 12 may be heated. In this
case, the temperature at the central portion of the black body 2
may become higher than the temperature at both ends of the black
body 2. In other words, the temperature distribution of the black
body 2 may form a two-dimensional curve in which the temperature is
highest at the center thereof. More convection of external air may
occur at both ends of the black body 2 and both ends of the 1a
surface 12 than at their central portions, and the heating effect
is not uniform on the whole of the 1a surface 12 in practice, not
in theory.
[0054] The temperature T2 of the 2a surface 22 may be set higher
than the temperature T1 of the 1a surface 12 (S44). The temperature
T2 may be delivered to the bent surface 42 adjacent to the 2a
surface 22, and the bent surface 42 may be connected to the arm 44.
Accordingly, temperature T2 may be substantially delivered to the
arm 44. Since the arm 44 is adjacent to the both ends of the black
body 2, the both ends of the black body 2 may be heated by the arm
44. Furthermore, since the temperature T2 is higher than the
temperature T1, the both ends of the black body 2 may be heated,
thereby correcting the temperature of the black body 2 to be
uniform at the both ends and the central portion of the black body
2. Accordingly, the thermal distribution may form a straight line,
not a quadratic curve.
[0055] On the other hand, the 1b surface 14 and the 2b surface 24
may be cooled. The cooled surfaces 14 and 24 may affect the copper
plate 30, and then the copper plate 30 may affect the heat-emitting
plate 28 connected to the heat-emitting member 27. Thereafter, heat
exchange may be performed by the fan 60 or the receiving unit 62 in
an air-cooling manner or a water-cooling manner.
[0056] If the cooled copper plate 30 does not exchange heat with
the outside, the 1b surface 14 and the 2b surface 24 may affect the
surface 1a surface 12 and the 2a surface 22. Accordingly, the black
body 2 is difficult to heat to a desired temperature.
[0057] In order to perform correction on a thermal imaging camera
at various temperatures, the above process may be performed while
varying the predetermined temperature of a black body.
[0058] Although an apparatus and method for controlling the
temperature of a black body has been described with reference to
the specific embodiments, it is not limited thereto. Therefore, it
will be readily understood by those skilled in the art that various
modifications and changes can be made thereto without departing
from the spirit and scope of the present invention defined by the
appended claims.
* * * * *