KR101731287B1 - Method and apparatus for compensating output of infrared sensor - Google Patents

Abstract

According to an embodiment of the present invention, there is provided a method of correcting an output of an infrared detector according to an ambient temperature, the method comprising the steps of: comparing a temperature of the infrared sensor with an ambient temperature of the infrared sensor; Expanding the width of the actual output range to be equal to the width of the allowable output range of the detector; And shifting the actual output range so that the extended actual output range is equal to the allowable output range.

Description

FIELD OF THE INVENTION The present invention relates to a method and apparatus for compensating the output of an infrared detector,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for correcting the output of an infrared detector of an infrared camera, and more particularly, to an output correction method and apparatus capable of improving the temperature resolution of an infrared detector.

An infrared camera (also referred to as a "thermal camera") is a device that captures an infrared image of a subject. The infrared camera includes an infrared detector that detects the infrared energy emitted from the subject. The infrared detector detects an infrared ray and converts the infrared ray into an electric signal. The data processing unit at the rear end of the detector converts the electric signal into temperature data and displays the temperature data so that the user can view the temperature distribution of the object on the screen.

In general, an infrared detector has a focal plane array (FPA) structure and is composed of a microbolometer made of a metal or semiconductor material. However, when a microbolometer is manufactured through a semiconductor process, the characteristics of the pixels constituting each bolometer are different from each other due to the characteristics of the material, the process, and so on. Therefore, all the pixels of the FPA have the same output In many cases, In particular, since the temperature resistance coefficient (TCR) of the bolometer changes when the temperature of the substrate on which the bolometer is formed, the temperature range outputted by the detector varies depending on the temperature around the detector even when the same subject is photographed.

For example, FIG. 1 shows, as an example, a conventional problem in which the actual output range for an object is determined according to the ambient temperature.

In general, the infrared detector can output the temperature data of the photographed subject to 14-bit data (that is, from 0 to 16383 in numerical form). Theoretically, the detector can output data over the entire range of the X-axis in FIG. 1. However, if the ambient temperature of the detector changes due to the above-described temperature problem, the temperature output range for the subject varies. For example, When the ambient temperature of the detector is 10 degrees, the detector outputs the temperature data of the subject only in the period from A to D, assuming that the subject between the eyes is photographed. Also, when the ambient temperature of the detector is 20 degrees, the detector can output the temperature data of the subject only in the C-E section. That is, when the ambient temperature is 10 ° C, the actual output range of the detector is A-D, and when the ambient temperature is 20 ° C, the actual output range of the detector is C-E.

As described above, since the output range of data is shifted according to the temperature change of the outside, the entire allowable output range (0-16383) can not be used properly. The temperature resolution is determined by the output range of the data. As described above, since the actual data use area is narrow, the temperature resolution is not good and the use range varies depending on the external temperature.

Patent Document 1: Korean Patent No. 10-1392721 (issued on May 08, 2014) Patent Document 2: Korean Patent No. 10-0586308 (published on June 08, 2006)

According to an embodiment of the present invention, there is provided a method and an apparatus for correcting an output of an infrared detector, the temperature range of a subject which can be measured by the detector is kept constant even when the temperature of the detector and the surrounding environment is changed to improve the temperature resolution.

According to an embodiment of the present invention, there is provided a method of correcting an output of an infrared detector according to an ambient temperature, the method comprising the steps of: comparing a temperature of the infrared sensor with an ambient temperature of the infrared sensor; Expanding the width of the actual output range to be equal to the width of the allowable output range of the detector; And shifting the actual output range so that the extended actual output range is equal to the allowable output range.

According to an embodiment of the present invention, the step of extending the width of the actual output range includes adjusting the sensor gain to extend the width of the actual output range, And shifting the actual output range by adjusting the output range.

According to an embodiment of the present invention, there is provided a method of correcting an output of an infrared detector according to an ambient temperature, the method comprising the steps of: determining, when an ambient temperature of the infrared detector is a first temperature, Calculating a first sensor gain that extends the width of the actual output range to be equal to the width of the allowable output range of the detector; Calculating a first sensor offset that shifts the actual output range such that the expanded actual output range when the ambient temperature is the first temperature is equal to the allowable output range; Calculating a second sensor gain that extends the width of the actual output range of the detector with respect to the temperature range of the object at the second temperature when the ambient temperature is the second temperature; And calculating a second sensor offset that shifts the actual output range so that the extended actual output range when the ambient temperature is the second temperature is included in the allowable output range. A method of calibrating the output of an infrared detector is provided.

According to an embodiment of the present invention, there is provided an apparatus for correcting an output of an infrared detector according to an ambient temperature, the apparatus comprising: an infrared detector capable of measuring a temperature of a subject; And a control unit for correcting an output of the infrared detector, wherein the infrared detector transmits a detector output to the ambient temperature information and the temperature of the object to the controller, and the controller controls the temperature of the object at the first ambient temperature A first sensor gain to extend the width of the actual output range of the detector with respect to the range so as to be equal to the width of the allowable output range of the detector, An apparatus for correcting the output of an infrared detector according to ambient temperature for calculating a first sensor offset that shifts a range.

According to an embodiment of the present invention, a temperature range of a subject, which can be measured by a detector, can be extended to an allowable output range of a detector, thereby having a technical effect of improving temperature resolution.

1 is a view for explaining an actual output range for a subject according to ambient temperature in the prior art,
2 is a block diagram of an infrared camera according to an embodiment of the present invention;
3 is a view for explaining an actual output range for a subject according to ambient temperature in an embodiment of the present invention,
4 is a flow chart for explaining an output correction method of an infrared detector according to an embodiment,
FIGS. 5A, 5B, and 6 are diagrams for explaining a method of correcting the output of the infrared detector when the ambient temperature is 10 degrees; FIGS.
7A and 7B are diagrams for explaining a method of correcting the output of the infrared detector when the ambient temperature is 20 degrees,
FIG. 8 is a flowchart illustrating a method of updating a non-uniformity correction (NUC) table according to an embodiment;
FIG. 9 is a flowchart illustrating a method of updating a non-uniformity correction (NUC) offset table according to an embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features, and advantages of the present invention will become more readily apparent from the following description of preferred embodiments with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms. Rather, the embodiments disclosed herein are provided so that the disclosure can be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

In this specification, when an element is referred to as being 'above' (or 'below', 'right', or 'left') of another element, it may be above (or below, ) Or it may mean that a third component may be interposed therebetween. Also, in the figures, numerical values such as length, width, thickness, etc. of the components are exaggerated for an effective explanation of the technical content.

Also, in this specification, expressions such as 'upper', 'lower (lower)', 'left', 'right', 'front', 'rear' And it is a relative expression used for convenience of explanation based on the drawings when describing the present invention with reference to the respective drawings.

Where the terms first, second, etc. are used herein to describe components, these components should not be limited by such terms. These terms have only been used to distinguish one component from another. The embodiments described and exemplified herein also include their complementary embodiments.

In the present specification, the singular form includes plural forms unless otherwise specified in the specification. The terms "comprise" and / or "comprising" used in the specification do not exclude the presence or addition of one or more other elements.

Hereinafter, the present invention will be described in detail with reference to the drawings. Various specific details are set forth in the following description of specific embodiments in order to provide a more detailed description of the invention and to aid in understanding the invention. However, it will be appreciated by those skilled in the art that the present invention may be understood by those skilled in the art without departing from such specific details. In some cases, it is noted that parts of the invention that are not commonly known in the art and are not largely related to the invention are not described in order to avoid confusion in describing the invention.

2 is a block diagram of an infrared camera according to an embodiment of the present invention.

Referring to FIG. 1, an infrared camera includes an infrared lens 10 for passing infrared rays, a shutter 20 for blocking infrared rays as needed, an infrared detector 12 for detecting infrared rays passing through the lens 10, (ADC) 40 and a digital-to-analog converter (DAC) 70 for performing analog-to-digital signal-to-analog conversion, .

The infrared lens 10 is a lens that transmits infrared light, and the detector 30 detects infrared rays that have passed through the infrared lens 10 and converts the detected infrared rays into an electric signal. The detector 30 may have, for example, a focal plane array (FPA) structure in which a plurality of pixels are arranged in a two-dimensional array, but the present invention is not limited thereto. Any means capable of detecting the infrared ray to measure the temperature of the object . The ADC 40 converts an electrical signal, which is an analog signal generated by the detector 30, into temperature data, which is a digital signal.

The detector 30 may measure the current ambient temperature of the detector and transmit the temperature information to the controller 60. In one embodiment, the detector 30 itself can sense the ambient temperature and transmit this temperature information to the controller 60, and in an alternative embodiment, for example, a temperature sensor is installed adjacent to the detector 30 And the temperature value sensed by the temperature sensor can be transmitted to the control unit 60.

The shutter 20 functions to block the infrared rays incident on the detector 30 through the lens 10, similar to the case where the shutter of the camera actually blocks the inflow of light from the outside of the camera. In one embodiment, the shutter 20 is used to block the infrared radiation incident on the detector 30 to update the NUC table used for nonuniformity correction (NUC) of temperature data. Therefore, if a method of updating the NUC table in a shutterless manner is adopted, a shutter may not be necessary.

The signal processing unit 50 can correct the temperature data received from the detector 30 and convert it into image data. For example, the signal processing unit 50 performs correction processing such as nonuniformity correction (NUC) and / or dead pixel processing on the temperature data. The signal processing unit 50 can also convert the temperature data into a thermal image (or "thermal image" or "thermal image") data. For example, thermal data is generated by converting temperature data subjected to nonuniformity correction and / or dead pixel processing into a matched color according to each temperature band. For example, a thermal image is generated by applying RGB values matched to respective temperature values of temperature data. Accordingly, for example, a color thermal image in which a high temperature is displayed in a red system and a low temperature in a blue system is generated, or a black and white thermal image in which a high temperature is displayed close to white and a low temperature is displayed close to black .

In one embodiment of the present invention, the signal processing unit 50 may include a control unit 60. The controller 60 can receive the temperature information of the detector 30, that is, the information about the ambient temperature around the detector 30 from the detector 30, and can correct the output value of the detector 30 based on this information . In one embodiment, the controller 60 may input the sensor gain and the sensor offset as a control signal for correcting the output value of the detector 30 to the detector 30. In this case, the controller 60 calculates the sensor gain and the sensor offset based on the temperature information of the detector, and inputs the calculated sensor gain and sensor offset to the detector 30. Since the signal output from the controller 60 is a digital signal, the sensor gain and the sensor offset are converted into analog signals through the DAC 70 and then input to the detector 30.

Here, 'sensor gain' is an element for determining the gain (gain) of the output of the infrared sensor of the detector 30, and 'sensor offset' is an element for determining the offset of the infrared sensor output. The temperature data output from the detector 30 to the signal processing unit 50 can be corrected. Since the term gain and offset are used for the nonuniformity correction (NUC) of the infrared camera, the gain and offset relating to the sensor output of the detector 30 are referred to as 'sensor gain' and 'sensor offset' And the gain and offset used in the NUC will be referred to as 'NUC gain' and 'NUC offset'.

In one embodiment, when the detector 30 is at the predetermined ambient temperature, the controller 60 calculates the sensor gain and the sensor offset value according to the ambient temperature and inputs the sensor gain and the sensor offset value to the detector 30, The narrow output range is output to the allowable output range of the detector. Specifically, the control unit 60 calculates the sensor gain value corresponding to the current ambient temperature. The sensor gain value is a value that can extend the width of the actual output range of the detector according to the temperature range of the subject at the current ambient temperature so as to be approximately equal to the width of the allowable output range of the detector 30. [

Thereafter, the controller 60 calculates a sensor offset value corresponding to the current ambient temperature. The sensor offset value at this time is a value that shifts the extended actual output range so as to be equal to or included in the allowable output range.

In this way, the controller 60 calculates the sensor gain and the sensor offset value for the current ambient temperature and inputs the sensor gain and the sensor offset value as the control signal to the detector 30. Thus, the detector 30 outputs the corrected output value (temperature data for the object) And output it to the processing section 50.

Although not shown in FIG. 2, the infrared camera may further include a display device for displaying image data output from the signal processing unit 50, and a communication unit for communicating with an external wired and / or wireless network. However, since these components are not related to the features of the present invention, their description will be omitted.

FIG. 3 is a view for explaining an actual temperature range for a subject in accordance with the ambient temperature of the infrared detector 30 in the embodiment. The sensor gain and the sensor offset value calculated by the controller 60 of FIG. 30 and outputs the temperature data output by the detector 30. [

Compared with the prior art of FIG. 1, the temperature of the subject can be expressed in a range almost equal to the allowable output range over the entire ambient temperature range. Therefore, the temperature of the subject can be expressed in a wider output range than in the prior art, so that the temperature resolution is improved.

Here, 'allowable output range' means the maximum output range that the detector can have, or the output range with the margin at this maximum output range. For a detector that outputs 14 bits of data, the allowable output range can range from 0 to 16383. However, it is preferable to place a slight margin out of the minimum value and the maximum value of the output. That is, in the embodiment shown in FIG. 3, the 'allowable output range' may be the A-B interval instead of the maximum output range (0-16383).

Hereinafter, an exemplary method for improving the temperature resolution over the entire ambient temperature range will be described with reference to FIGS. 4-7.

4 is a flowchart illustrating an output correction method of an infrared detector according to an exemplary embodiment of the present invention. For convenience of explanation, it is assumed that the detector 30 to be calibrated has an output range according to the ambient temperature as in Fig.

First, in step S120, the ambient temperature of the detector 30 is set to a predetermined first temperature. Where the first temperature may be, for example, 10 degrees Celsius. The method of adjusting the ambient temperature to a predetermined temperature may vary. For example, after the infrared camera is placed in a chamber capable of controlling temperature, the temperature of the chamber can be adjusted to set the ambient temperature of the detector 30.

When the ambient temperature reaches 10 degrees and the ambient temperature information is transmitted from the detector 30 to the controller 60, the controller determines in step S130 that the actual output range to be output by the detector 30 is within the permissible output range of the detector The sensor gain and the sensor offset are calculated.

In FIG. 1, when the ambient temperature is 10 degrees, the detector 30 assumes that the actual output range of the A-D section is from -20 degrees to 120 degrees. 5A, assuming that the permissible output range of the detector 30 is a section from A to B, the width of the actual output range of the detector (i.e., the width of the AD section) is The sensor gain value is calculated so as to be equal to the width of the allowable output range (i.e., the width of the AB section). As shown in FIG. 5A, the calculated sensor gain value is a sensor gain value such that the actual output range of the detector is expanded by the same width as the allowable output range (A-B section) when the ambient temperature is 10 degrees.

Thereafter, in step S130, the controller 60 calculates a sensor offset value that shifts the actual output range so that the extended actual output range becomes equal to the allowable output range (A-B section). As shown in FIG. 5B, the calculated sensor offset value is a sensor offset value such that when the ambient temperature is 10 degrees, the extended actual output range of the detector is slightly shifted to the right to be equal to the allowable output range (AB section) .

In this way, in step S130, the controller calculates the sensor gain and the sensor offset with respect to the current ambient temperature so that the detector can detect the permissible output range AB of the detector at the corresponding ambient temperature (i.e., 10 degrees) It is possible to output the temperature data over a wide interval, thereby improving the temperature resolution.

Meanwhile, FIG. 6 graphically shows the principle of changing the actual output range of the detector according to the change of the sensor gain and the sensor offset. As shown in FIG. 1, before the sensor gain and the sensor offset are corrected, the output of the detector is the same as the black graph of FIG. That is, the data output value of the section A-D is output for a subject between -20 degrees and 120 degrees. On the other hand, if the sensor gain calculated in step S130 is input to the detector, the gain (slope) of the graph is changed to be a blue graph. If the sensor offset calculated in step S130 is further input to the detector, Is vertically moved upward, and finally becomes a red graph. Accordingly, the temperature resolution is improved by having the actual output range equal to the permissible output range (A-B section) of the detector for an object between -20 degrees and 120 degrees.

Referring again to FIG. 4, the ambient temperature of the detector is set to the second temperature through steps S140, S150 and S110. In one embodiment, the second temperature may be, for example, 20 degrees Celsius.

When the ambient temperature reaches the second temperature (i.e., 20 degrees) and the ambient temperature information is transmitted from the detector 30 to the controller 60, step S130 is performed again. In this step S130, the controller 60 calculates the sensor gain and the sensor offset for the second temperature. This calculation process is the same as or similar to the calculation process described above with respect to the first temperature.

For example, in FIG. 1, when the ambient temperature is 20 degrees, it is assumed that the detector 30 has the actual output range of the C-E section for a subject of -20 to 120 degrees. In this case, it is assumed that the permissible output range of the detector 30 is a section from A to B. Therefore, in this step S130, the width of the actual output range of the detector (i.e., the width of the CE section) (The width of the AB section). As shown in FIG. 7A, the calculated sensor gain value is a sensor gain value such that the actual output range of the detector is expanded by the same width as the allowable output range (A-B section) when the ambient temperature is 20 degrees.

In one embodiment, the controller 60 may calculate the sensor gain value based on the current ambient temperature. However, in an alternative embodiment, the sensor gain value for this second temperature may be the sensor gain value when the ambient temperature is at the first temperature, i.e., the sensor gain value calculated at step S130 at the first temperature, The temperature can be used as it is.

In step S130, the controller 60 calculates a sensor offset value that shifts the actual output range so that the extended actual output range becomes equal to the allowable output range (A-B section). As shown in FIG. 7B, the calculated sensor offset value is a sensor offset value such that when the ambient temperature is 20 degrees, the extended actual output range of the detector is slightly shifted to the left to be equal to the allowable output range (AB section) .

When the ambient temperature is the second temperature (i.e., 20 degrees), the controller 60 calculates the sensor gain and the sensor offset with respect to the current ambient temperature in step S130. As a result, Temperature data can be output over a wide range as the allowable output range (AB section) of the detector at the temperature (20 degrees).

4, the ambient temperature of the detector may be set to the third temperature through steps S140, S150, and S110. Here, the third temperature may be, for example, 30 degrees centigrade, and the controller 60 may calculate the sensor gain and the sensor offset using the same or similar method for the third temperature as described with reference to Figs.

In this manner, the control unit 60 repeatedly executes step S130 for each predetermined ambient temperature to calculate the sensor gain and the sensor offset at the corresponding temperature for each predetermined ambient temperature. For example, when the first to fifth temperatures are set at intervals of 10 degrees from 10 degrees Celsius to 50 degrees Celsius, the sensor gains at the respective temperatures (i.e., 10 degrees, 20 degrees, 30 degrees, 40 degrees, When the sensor offset and the sensor offset are applied to the detector 30, the data output can be expanded to the same or similar range as the allowable output range (AB section) at each preset temperature as shown in FIG. 3 , So that the subject can be expressed within a wider data output range compared with the prior art, thereby improving the temperature resolution.

On the other hand, the sensor gain and the sensor offset values calculated for each preset temperature may be stored in an arbitrary storage device (not shown) each time the temperature is calculated.

Then, in step S160 of FIG. 4, the sensor gain and the sensor offset for an arbitrary ambient temperature other than the preset temperature can be calculated. In this case, when the ambient temperature is any temperature other than the predetermined temperature, the sensor gain and the sensor offset of the corresponding temperature can be obtained based on the sensor gain and the sensor offset values for the predetermined temperature. For example, when the current ambient temperature is 15 degrees, the sensor gain for this 15 degree can be used as it is, for example, when the ambient temperature is 10 degrees. Further, the sensor offset for 15 degrees can be calculated from the sensor offset calculated when the ambient temperature is 10 degrees and 20 degrees, for example, by using an interpolation method or the like.

Next, if it is necessary to update the table of nonuniformity correction (NUC) after step S160, an update operation of the NUC table may be performed in step S170.

The step S160 of calculating the sensor gain and the sensor offset with respect to the ambient temperature other than the preset temperature and the NUC table updating step S170 in FIG. 4 may be omitted according to the specific embodiment.

Hereinafter, the NUC table update step (S170) of FIG. 4 will be described in detail with reference to FIG.

8 is a flowchart illustrating a method of updating a non-uniformity correction (NUC) table according to an exemplary embodiment of the present invention. First, in step S1710, the ambient temperature of the detector 30 is fixed to a predetermined temperature. For example, an infrared camera can be placed in a temperature-adjustable chamber and the ambient temperature around the detector can be fixed at a predetermined temperature by adjusting the temperature of the chamber.

Thereafter, in step S1720, the sensor gain and the sensor offset for the predetermined temperature are applied to the detector. That is, the sensor gain and the sensor offset calculated for the predetermined temperature can be input to the detector 30 by performing step S130 of FIG. If the predetermined temperature is not the predetermined temperature in FIG. 4, the sensor gain and the sensor offset for the predetermined temperature may be obtained through interpolation or the like in step S160 and input to the detector 30, S1720), the detector 30 can output temperature data with improved temperature resolution as shown in Fig.

Next, in step S1730, an arbitrary subject is set to the first temperature. Preferably, a black body capable of temperature control can be used as the subject. When the temperature of the subject is fixed to the first temperature, the detector 30 captures the subject and acquires the first temperature data in step S1740.

Thereafter, in step S1750, the subject is set to the second temperature, and in step S1760, the detector 30 photographs the subject to acquire the second temperature data.

Since the temperature data at two different temperatures are obtained through the above-described steps S1730 to S1760, the NUC gain (slope) and the NUC offset can be calculated therefrom (S1770), and the calculated NUC gain and NUC offset To the existing NUC table (S1780).

9 shows an exemplary method for updating the NUC offset in the NUC table using the shutter 20 of the infrared camera when a thermally adjustable subject (e.g., a blackbody) is not available, as an alternative embodiment to update the NUC table .

First, in step S210, the shutter of the infrared camera is closed, and the current ambient temperature of the detector is measured and transmitted to the controller 60 (S220). In one embodiment, the detector 30 itself can sense the ambient temperature and transmit this temperature information to the controller 60, and in an alternative embodiment, for example, a temperature sensor is installed adjacent to the detector 30 And the temperature value sensed by the temperature sensor may be transmitted to the control unit 60.

Thereafter, the controller 60 applies the sensor gain and the sensor offset to the detector ambient temperature to the detector 30 in step S230. For example, if the sensor gain and the sensor offset calculated for each preset temperature are stored in the storage device according to the flowchart of FIG. 4, the sensor gain and the sensor offset for the current ambient temperature may be calculated and applied to the detector .

Next, in step S240, the detector 30 photographs the shutter 20 to acquire temperature data of the shutter. Assuming that the temperature of the shutter 20 and the ambient temperature of the detector 30 are equal to each other, the temperature value acquired by the detector 30 (i.e., the temperature data of the shutter) and the actual ambient temperature value I.e., the NUC offset (S250). The calculated NUC offset is input to the existing NUC table to update the NUC table (S260). Thereafter, the shutter 20 is opened (S270) and an arbitrary subject can be photographed.

As described above, although the present invention has been described with reference to the limited embodiments and drawings, the present invention is not limited to the above embodiments. It will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the present invention as defined by the appended claims. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the scope of the appended claims, as well as the appended claims.

10: Lens 20: Shutter
30: detector 40: analog-to-digital converter (ADC)
50: signal processing unit 60:
70: Digital-to-Analog Converter (DAC)

Claims (13)

A method of correcting an output of an infrared detector according to an ambient temperature,
Expanding the width of the actual output range of the detector with respect to the temperature range of the object at the ambient temperature equal to the width of the allowable output range of the detector when the ambient temperature of the infrared detector is any temperature; And
And shifting the actual output range such that the extended actual output range is equal to the allowable output range. The method according to claim 1,
Wherein expanding the width of the actual output range comprises adjusting the sensor gain to extend the width of the actual output range. The method according to claim 1,
Wherein the step of shifting the actual output range comprises shifting the actual output range by adjusting a sensor offset. A method of correcting an output of an infrared detector according to an ambient temperature,
A first sensor gain which expands the width of the actual output range of the detector with respect to the temperature range of the object at the first temperature to be equal to the width of the allowable output range of the detector when the ambient temperature of the infrared detector is at the first temperature, ;
Calculating a first sensor offset that shifts the actual output range such that the expanded actual output range when the ambient temperature is the first temperature is equal to the allowable output range;
Calculating a second sensor gain that extends the width of the actual output range of the detector with respect to the temperature range of the object at the second temperature when the ambient temperature is the second temperature; And
And calculating a second sensor offset that shifts the actual output range so that the extended actual output range when the ambient temperature is the second temperature is included in the allowable output range. A method of calibrating the output of an infrared detector according to ambient temperature. 5. The method of claim 4,
Wherein the second sensor gain is equal to the first sensor gain. A method of correcting an output of an infrared detector according to an ambient temperature. 5. The method of claim 4,
A third sensor gain that extends the width of the actual output range of the detector at the third temperature with respect to a third temperature between the first temperature and the second temperature and a third sensor offset that shifts the actual output range And correcting the output of the infrared detector according to the ambient temperature. The method according to claim 6,
The third sensor gain is equal to the first sensor gain,
Wherein the third sensor offset is calculated using an interpolation method based on the first and second sensor offsets. An apparatus for correcting an output of an infrared detector according to ambient temperature,
An infrared detector capable of measuring a temperature of a subject; And
And a controller for correcting an output of the infrared detector,
The infrared detector transmits the detector output of the ambient temperature information and the temperature of the object to the controller,
Wherein the control unit includes a first sensor gain that expands the width of the actual output range of the detector with respect to the temperature range of the object at the first ambient temperature to be equal to the width of the allowable output range of the detector, Wherein the first sensor offset calculating means calculates a first sensor offset that shifts the actual output range so that the range is equal to the allowable output range. 9. The method of claim 8,
Wherein when the ambient temperature of the infrared detector is the first ambient temperature, the controller inputs the first sensor gain and the first sensor offset to the infrared detector, wherein the output of the infrared detector Correction device. 9. The method of claim 8,
Wherein the control unit includes a second sensor gain that extends the width of the actual output range of the detector with respect to the temperature range of the object at the second ambient temperature and a second sensor gain that extends the actual output range to the allowable output range And the second sensor offset for shifting the output range can be further calculated. The apparatus according to claim 10, wherein the first sensor gain is used as the second sensor gain. 11. The method of claim 10,
A third sensor gain that extends the width of the actual output range of the detector at the third ambient temperature with respect to a third ambient temperature between the first ambient temperature and the second ambient temperature, And the third sensor offset for shifting the second sensor offset can be further calculated. 13. The method of claim 12,
Wherein the controller calculates the third sensor offset using an interpolation method based on the first and second sensor offsets.

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