JP2011106885A - Thermography apparatus, image processing method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To output, when the temperature distribution of an object having a wide temperature range is imaged, the image data of the object continuously. <P>SOLUTION: A sensor control part 11 switches between first and second temperature ranges with predetermined timing and supplies information on the switched first or second temperature range to an infrared sensor 4. A signal processing part 12 takes the weight average of image signals over a predetermined period on the basis of the information on the first or second temperature range. A writing part 18 writes image data obtained from the processed image signals into an image storage part for each of the first and second temperature ranges. A temperature range detection part 17 detects the temperature range of the object from the image data and selects the first or second temperature range in accordance with the temperature range of the object. A reading part 19, in accordance with the first or second temperature range selected by the temperature range detection part 17, reads the image data written with either the first or second temperature range out of the image storage part and outputs it. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a thermography apparatus, an image processing method, and a program that are suitable for application when, for example, an object having a large temperature increase and decrease is imaged and output as a thermal image.

  2. Description of the Related Art Conventionally, a thermographic apparatus that can display a temperature distribution of an object on a display device as a thermal image that is color-coded is used. The thermography device outputs to the display device image data displayed as a thermal image that is color-coded, for example, high temperature is white and low temperature is blue according to the intensity of infrared light emitted from the object.

  In the thermography apparatus, in many cases, two temperature ranges representing temperature ranges in which temperature measurement is possible are prepared in advance. And when a thermography apparatus measures the temperature of a target object, a temperature range is changed according to the maximum temperature of a target object. As the temperature range, for example, the first temperature range is set to 0 to 120 degrees Celsius, the second temperature range is set to 0 degrees to 300 degrees Celsius, and the third temperature range is set to 200 degrees to 1500 degrees Celsius in advance. Has been. The thermography device includes a temperature range changing device that switches a temperature range. The temperature range changing device has a processing function of changing an accumulation time in order to change the sensitivity of the sensor, and includes an aperture and a filter of an optical system provided in the camera unit. A mechanism is provided for controlling whether or not the optical system is inserted into the optical axis. This temperature range changing device can change the temperature range by changing the sensor accumulation time, moving the diaphragm and filter, and controlling the amount of infrared light guided from the optical system of the camera unit to the infrared detection element. it can.

FIG. 5 shows the relationship between the temperature of the object and the value output from the infrared detection element for each temperature range.
The characteristic line a shows the relationship between the temperature of the object when the first temperature range is selected and the energy of the infrared light incident on the infrared detection element.
The characteristic line b shows the relationship between the temperature of the object when the second temperature range is selected and the energy of infrared rays incident on the infrared detection element.
The characteristic line c shows the relationship between the temperature of the object when the third temperature range is selected and the energy of infrared rays incident on the infrared detection element.

  As shown in FIG. 5, the thermography apparatus stores in advance a relationship between the output of the infrared detection element and the temperature in each temperature range as a temperature table. When the infrared light receiving energy is detected by the infrared detecting element, the temperature range is changed according to the maximum temperature of the object, and temperature data is obtained by referring to the output of the infrared detecting element in the temperature table of each temperature range. In this way, the thermographic apparatus can accurately measure the temperature of the object. And if the thermography apparatus is in the range of the changed temperature range, it can color-code appropriately as a thermal image, and can display it on a display apparatus.

  Here, the case where the temperature of a target object increases / decreases in the range of -20 degreeC-400 degreeC is assumed. At this time, if the first temperature range is maintained, even if the maximum temperature of the object increases from 300 ° C. to 400 ° C., only white is displayed, and the user cannot know the increase in temperature. For this reason, the user performs an operation of changing from the first temperature range to the second temperature range. By this operation, when the maximum temperature of the object increases from 300 ° C. to 400 ° C., a new color is displayed and the user can know the temperature rise.

  Further, if an appropriate temperature range is not set according to the maximum temperature of the object, another problem occurs. For example, if the temperature of the object increases or decreases in the range of 30 ° C. to 80 ° C., noise is easily superimposed on the displayed thermal image while being set to the second temperature range, and the visibility of the thermal image is increased. Decreases. For this reason, it is necessary to improve visibility by changing to an appropriate temperature range depending on the temperature of the object.

  Patent Document 1 discloses a technique for adjusting an accumulation time depending on an object, and Patent Document 2 discloses a technique for automatically changing a temperature range according to a target temperature. Patent Document 3 discloses a technique in which a sensor external circuit adjusts a gain or the like according to a target temperature.

JP-A-6-26936 JP-A-9-101207 JP-A-8-223485

By the way, when the temperature range is changed manually or automatically, it takes about several seconds until the thermal image is updated and displayed in the changed temperature range.
Here, the first and second temperature ranges correspond to the dynamic range of an infrared sensor that outputs an image signal. It is known that the dynamic range becomes narrower when the integration time indicating the time for storing the image signal output from the infrared sensor for a certain period of time becomes longer, and the dynamic range becomes wider when the integration time becomes shorter.

  When the setting of the thermography device is changed to either the first or second temperature range, the integration time of the infrared sensor must be changed according to the changed temperature range. The infrared sensor is set with sensor offset data (hereinafter simply referred to as “offset data”) suitable for the changed temperature range. The offset data is data for setting the infrared sensor to an initial value when the temperature range is changed, and the variation in the level of the image signal output by each of the plurality of elements included in the infrared sensor is flattened. Used to remove noise. And since it takes several seconds to complete the setting of the integration time and the offset data, the display of the thermal image is interrupted, and the user cannot continuously grasp the temperature change of the object.

  For example, the case where the temperature of a target object is measured in the 2nd temperature range (0 degreeC-500 degreeC) is assumed. At this time, when the maximum temperature of the object becomes 100 ° C. or less, the temperature is changed to the first temperature range (−40 ° C. to 120 ° C.), and the temperature change of the object is observed in detail and superimposed on the thermal image. There is a demand to reduce noise. However, when the second temperature range is changed to the first temperature range, the offset data is set in the infrared sensor, and the image is interrupted for several seconds.

  In the technique disclosed in Patent Document 1, the stabilization time after changing the accumulation time corresponding to the integration time of the image signal in the infrared sensor is not considered, and image data cannot always be acquired. For this reason, when the temperature range is switched, it takes much time to update the thermal image.

In the technique shown in Patent Document 2, even if the temperature range is automatically changed according to the target temperature, the offset data must be set, and the image cannot be updated immediately by switching the temperature range.
Further, when the technique shown in Patent Document 3 is used, for example, when the gain of the preamplifier is adjusted to double, noise is generated twice, so that a mechanism for removing the noise is newly required, and the apparatus is downsized. It was difficult.

  The present invention has been made in view of such a situation. When a thermal image is obtained by capturing an image of an object with a large increase / decrease in the maximum temperature, the object is continuously detected even when the temperature range is switched. It is an object to output image data to be displayed on the display unit as a thermal image.

The present invention provides a first temperature range that is set when a maximum temperature of an object is less than a predetermined threshold among a temperature range including a temperature range from a minimum temperature to a maximum temperature of the object, and the object Switching to a second temperature range different from the first temperature range, which is set when the maximum temperature is equal to or higher than a predetermined threshold, according to the intensity of infrared light emitted from the object Information about the switched first or second temperature range is supplied to the infrared sensor that outputs the image signal.
Next, based on the information about the first or second temperature range supplied by switching at a predetermined timing, the image signals output from the infrared sensor are added and averaged over a predetermined period.
Next, image data obtained from the processed image signal is written into the image storage unit for each first or second temperature range switched at a predetermined timing.
Next, from the image data, the temperature range of the object is detected, the first or second temperature range is selected according to the temperature range of the object, and according to the selected first or second temperature range, Image data written in either the first or second temperature range is read from the image storage unit and output.

  By doing in this way, even if it switched the 1st or 2nd temperature range, it became possible to output the image data displayed on a display part as a thermal image of a target object continuously.

  According to the present invention, the image signal output from the infrared sensor is processed by the first or second temperature range switched at a predetermined timing, and image data obtained from the image signal is always stored in the image storage unit. . Then, in accordance with the maximum temperature of the object, the image data written in either the first or second temperature range is read from the image storage unit and output. For this reason, the time required for changing the temperature range can be shortened, and image data can be output while maintaining continuity.

It is a block diagram which shows the example of the infrared imaging device in one embodiment of this invention. It is a flowchart which shows the process example which acquires the image data of the thermography apparatus in one embodiment of this invention. It is a flowchart which shows the process example until the writing part in one embodiment of this invention writes image data in the 1st and 2nd image storage part. It is a flowchart which shows the process example in which the reading part in one embodiment of this invention reads image data from the 1st and 2nd image memory | storage part. It is explanatory drawing which shows the relationship between the temperature of the conventional target object, and the value which an infrared rays detection element outputs for every temperature range.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In the present embodiment, an example will be described in which the present invention is applied to a thermography apparatus 1 that automatically changes the temperature range to capture infrared light of the object 2 and outputs image data displayed on the display device 5 as a thermal image. .

FIG. 1 shows an internal configuration example of a thermography apparatus 1 of the present example.
The thermography apparatus 1 transmits an infrared ray radiated from the object 2 and converges the infrared ray at a predetermined position, and an infrared sensor 4 that outputs an image signal corresponding to the intensity of the infrared light converged by the lens 3. An image processing unit 10 that performs predetermined processing on the image signal, a display device 5 that displays a thermal image color-coded according to the temperature distribution of the object 2 based on the image data output from the image processing unit 10; Is provided.

  The image processing unit 10 includes a sensor control unit 11 that controls the operation of the bolometer-type infrared sensor 4, a signal processing unit 12 that performs predetermined processing on an image signal input from the infrared sensor 4, and the signal processing unit 12 performs processing. A first image storage unit 20a and a second image storage unit 20b that temporarily store image data obtained from the applied image signal are provided. The signal processing unit 12 includes an addition / average unit 12a that adds and averages image signals. In addition, the image processing unit 10 includes a writing unit 18 that writes image data to the first image storage unit 20a and the second image storage unit 20b, and images from the first image storage unit 20a and the second image storage unit 20b. A reading unit 19 for reading data is provided.

  The image processing unit 10 receives the image data output from the signal processing unit 12, detects the maximum temperature of the object 2, and detects a temperature range suitable for displaying a thermal image. Is provided. The temperature range detection unit 17 instructs the reading unit 19 to read the image data, and the reading unit 19 displays the image data read from the first image storage unit 20a or the second image storage unit 20b on the display device 5. Output to. The display device 5 displays a thermal image of the object 2 based on the image data received from the reading unit 19.

  The image processing unit 10 stores a clock output unit 13 that supplies a predetermined clock to the sensor control unit 11, a first integration time storage unit 14a that stores a first integration time, and first offset data. The first offset data storage unit 15a is provided. Similarly, the image processing unit 10 includes a second integration time storage unit 14b that stores a second integration time, and a second offset data storage unit 15b that stores second offset data. The first and second integration times and the first and second offset data are data set by the sensor control unit 11 in the first or second infrared sensor 4. It is acquired in advance before the start of the imaging process performed by the thermographic apparatus 1, and is stored in the first offset data storage unit 15a and the second offset data storage unit 15b, respectively.

  In this example, the first temperature range is set when the maximum temperature of the object 2 is less than a predetermined threshold among the temperature ranges including the temperature range from the lowest temperature of the object 2 to the highest temperature. The second temperature range is a temperature range that is set when the maximum temperature of the object 2 is equal to or higher than a predetermined threshold, and is different from the first temperature range. In this example, −40 ° C. to 120 ° C. is set as the first temperature range, and 0 ° C. to 500 ° C. is set as the second temperature range (see FIG. 5).

Next, an operation example of the thermography apparatus 1 will be described.
The sensor control unit 11 uses the switching clock supplied from the clock output unit 13 to switch to the first or second temperature range at a predetermined switching timing, and relates to the switched first or second temperature range. As information, the integration time and offset data corresponding to this temperature range are supplied to the infrared sensor 4 and the signal processing unit 12.

  When infrared light from the object 2 is input to the infrared sensor 4 via the lens 3, the infrared sensor 4 outputs an image signal to the signal processing unit 12. In the infrared sensor 4 of this example, the dynamic range when the image signal is output from the infrared light is changed by the integration time supplied from the sensor control unit 11.

  In timing 16a, the first integration time read from the first integration time storage unit 14a and the first offset data read from the first offset data storage unit 15a are input to the sensor control unit 11 with the same clock. Indicates to do. Similarly, the timing 16b indicates that the second integration time read from the second integration time storage unit 14b and the second offset data read from the second offset data storage unit 15b are the same clock with the sensor control unit. 11 indicates input. As described above, the sensor control unit 11 obtains a set of integration time and offset data at a predetermined timing, and inputs the integration time and offset data to the infrared sensor 4 so that the first or second temperature range is obtained. Switching.

  Then, the first and second integration times and the first and second offset data are simultaneously input to the signal processing unit 12 by the sensor control unit 11. For this reason, the signal processing unit 12 can know in which temperature range the infrared sensor 4 has output the image signal.

  The adder / average unit 12a included in the signal processing unit 12 applies the image signal input from the infrared sensor 4 to the image signal input from the sensor control unit 11 based on information on the first or second temperature range that is switched and supplied at a predetermined timing. On the other hand, addition processing and averaging processing are performed during a predetermined period (in this example, the number of frames). Then, the addition / average unit 12 a outputs the processed image signal to the writing unit 18.

  Based on the information about the first or second temperature range received from the sensor control unit 11, the signal processing unit 12 outputs the image signal in the temperature range of the first or second temperature range. Is determined. When the signal processing unit 12 outputs an image signal, information regarding the first or second temperature range is attached to the image data obtained from the image signal.

  The information regarding the first or second temperature range includes information indicating in which temperature range the image signal is output. The information related to the first temperature range includes the first integration time for integrating the image signal and the first offset data, and the information related to the second temperature range includes the second integration time for integrating the image signal. Integration time and second offset data are included.

  When the writing unit 18 receives the image data from the signal processing unit 12, the writing unit 18 performs the first or second temperature range switched by the sensor control unit 11 according to the information about the temperature range attached to the image data. The image data is written into the image storage unit 20a and the second image storage unit 20b. In this example, when the infrared sensor 4 is set to the first temperature range, the writing unit 18 stores the image data obtained from the image signal output in the first temperature range in the first image storage unit 20a. Write. On the other hand, when the infrared sensor 4 is set to the second temperature range, the writing unit 18 writes the image data obtained from the image signal output in the second temperature range to the second image storage unit 20b.

  Then, the image data is supplied to the temperature range detection unit 17 at the same timing when the image data is written into the first image storage unit 20a or the second image storage unit 20b. The temperature range detection part 17 detects the temperature range of the target object 2 from the acquired image data, selects the first or second temperature range according to the temperature range of the target object 2, and the thermal image of an appropriate temperature range. The readout unit 19 is instructed to read out image data that can be displayed as

  Specifically, when receiving the image data from the signal processing unit 12, the temperature range detection unit 17 sets the highest temperature data in the thermal image of one frame as the maximum temperature from the temperature data included in the image data. To detect. The temperature data is represented by 12 bits and varies from 000 to FFF in hexadecimal notation. Upon receiving the maximum temperature for the thermal image signal for 8 frames, the temperature range detection unit 17 averages the 8 maximum temperatures obtained from the image data for 8 frames and generates an average maximum temperature. Here, at the maximum temperature related to the thermal image for only one frame, there is a risk of detecting the true maximum temperature of the target object due to noise. For this reason, the temperature range detection unit 17 averages the maximum temperatures related to the thermal images for eight frames, obtains the average maximum temperature, and sets the average maximum temperature as the true maximum temperature of the object, so that the first or second temperature is obtained. This is used as a criterion for switching to one of the ranges.

  Based on a read instruction from the temperature range detection unit 17, the reading unit 19 writes data from either the first image storage unit 20a or the second image storage unit 20b in either the first or second temperature range. The read image data is read out and output to the display device 5. The display device 5 displays a thermal image of the object 2 based on the image data and information on the temperature range attached to the image data.

The image display algorithm used in the thermographic apparatus 1 of this example varies the thermal image displayed on the display apparatus 5 according to the following two conditions.
First condition: When the maximum temperature of the object 2 is lower than a threshold value (for example, 120 ° C.), a thermal image based on the image data read from the first image storage unit 20a is displayed on the display device 5.
Second condition: When the maximum temperature of the object 2 is equal to or higher than a threshold value (for example, 120 ° C.), a thermal image based on the image data read from the second image storage unit 20 b is displayed on the display device 5.
Then, the image processing unit 10 updates the thermal image displayed on the display device 5 at 2 Hz.

FIG. 2 shows a processing example for acquiring image data performed by the infrared imaging device and the signal processing unit 12.
First, the sensor control unit 1 sets the first integration time read from the first integration time storage unit 14 a and the first offset data read from the first offset data storage unit 15 a in the infrared sensor 4. (Step S1).

  Next, the infrared sensor 4 waits until the set first integration time is stabilized (steps S2 to S4). The standby time in step S2 corresponds to the time for one frame, and the same applies to the subsequent steps S2 to S4. The infrared sensor 4 stands by without outputting an image signal for a total time of 10 frames (167 milliseconds).

  Next, the infrared sensor 4 outputs the image signal of the object 2 with the first integration time from the infrared light input through the lens 3, and the signal processing unit 12 acquires the image signal (steps S5 to S7). ). Here, in order for the signal processing unit 12 to acquire an image signal, a time corresponding to three frames (50 milliseconds) is required.

  Then, the signal processing unit 12 adds and averages the acquired image signals, and the writing unit 18 writes the image data obtained from the image signals in the first image storage unit 20a (step S8). However, the signal processing unit 12 may output the obtained image signal as it is without performing addition averaging, and the writing unit 18 may write the image data obtained from the image signal into the first image storage unit 20a. .

  Next, the sensor control unit 1 sets the second integration time read from the second integration time storage unit 14b and the second offset data read from the second offset data storage unit 15b in the infrared sensor 4. (Step S10).

  Next, the infrared sensor 4 waits until the set second integration time is stabilized (steps S11 to S12). The standby time in step S11 corresponds to the time for one frame, and the same applies to the subsequent steps S12 to S13. The infrared sensor 4 stands by without outputting an image signal for a total time of 10 frames (167 milliseconds).

  Next, the infrared sensor 4 outputs the image signal of the object 2 with the second integration time from the infrared light input through the lens 3, and the signal processing unit 12 acquires the image signal (steps S14 to S16). ). Here, in order for the signal processing unit 12 to acquire an image signal, a time corresponding to three frames (50 milliseconds) is required.

  Then, the signal processing unit 12 adds and averages the acquired image signals, and the writing unit 18 writes the image data obtained from the image signals in the second image storage unit 20b (step S17). However, the signal processing unit 12 may output the obtained image signal as it is without performing addition averaging, and the writing unit 18 may write the image data obtained from this image signal into the second image storage unit 20b. .

  Note that the standby time in steps S2 to S4 and S11 to S13 is not limited to 10 frames (167 milliseconds), but waits for the stabilization time after the first offset data is set in the first offset data storage unit 15a. That's fine. In addition, the time for acquiring images in steps S5 to S7 and S14 to S16 is not limited to 3 frames (50 milliseconds), and may be 1 frame or 10 frames.

  FIG. 3 shows a processing example until the writing unit 18 writes the image data into the first image storage unit 20a or the second image storage unit 20b.

  First, the sensor control unit 11 sets the first integration time and the first offset data in the infrared sensor 4 (steps S21 and S22). Next, after the signal processing unit 12 processes the image signal output from the infrared sensor 4, the writing unit 18 writes the image data in the first image storage unit 20a (step S23).

  Next, the sensor control unit 11 sets the second integration time and the second offset data in the infrared sensor 4 (steps S24 and S25). Next, after the signal processing unit 12 processes the image signal output from the infrared sensor 4, the writing unit 18 writes the image data in the second image storage unit 20b (step S26).

  FIG. 4 shows an example of processing in which the reading unit 19 reads image data from the first image storage unit 20a or the second image storage unit 20b.

  First, the temperature range detection part 17 detects the temperature range of the target object 2 based on the image data obtained from the image signal output from the signal processing part 12 (step S31). Next, the temperature range detection unit 17 detects the maximum temperature of the object 2 from the image data, compares the maximum temperature with a threshold value, and the temperature range suitable for displaying a thermal image is the first or second temperature. It is determined which of the ranges (step S32).

  When it is determined that the first temperature range is appropriate, the temperature range detection unit 17 instructs the reading unit 19 to read image data from the first image storage unit 20a in order to meet the first condition described above. Is given (step S33). On the other hand, if it is determined that the second temperature range is appropriate, the temperature range detection unit 17 reads the image data from the second image storage unit 20b to the reading unit 19 in order to meet the second condition described above. An instruction is given (step S34).

  Then, the reading unit 19 reads the image data from either the designated first image storage unit 20a or the second image storage unit 20b and outputs the image data to the display device 5 (step S35).

  According to the thermography apparatus 1 according to the present embodiment described above, the image data of the object 2 is always stored alternately in two types of temperature ranges. For this reason, even when the maximum temperature of the object 2 changes and the temperature range needs to be changed, it is possible to switch the thermal image displayed on the display device 5 with a delay of about several tens of milliseconds. . Then, by instantaneously switching the temperature range, there is an effect that a thermal image with a better NETD (Noise Equivalent Temperature Difference) can be displayed on the display device 5 satisfactorily.

  In addition, since image data is acquired from the infrared sensor 4 by switching between two types of integration times, there is an effect that NETD is improved as compared with changing the gain of the infrared sensor 4 and the like.

  In addition, the information about the first temperature range includes the first integration time and the first offset data, and the information about the second temperature range includes the second integration time and the second offset data. Yes. And if the infrared sensor 4 receives the information regarding the 1st or 2nd temperature range, the infrared sensor 4 can output an image signal according to this information. For this reason, the infrared sensor 4 has an effect that an appropriate image signal can be output in accordance with the first or second temperature range set by the sensor control unit 11.

  Further, since the infrared sensor 4 stands by until the set first or second integration time is stabilized, the level of the output image signal is stabilized. Further, since the signal processing unit 12 adds and averages the image signal every predetermined number of frames, there is an effect that noise of the obtained image data is made uniform.

<Modification>
Instead of the infrared sensor 4 that can change the integration time, an infrared sensor that changes the bias voltage and gain may be used. In this case, the sensor control unit 11 can change the temperature range of the thermal image displayed on the display device 5 simply by giving an instruction to change the bias voltage to the infrared sensor.

  Moreover, the temperature range to be used is not limited to two types, and three or more types of temperature ranges may be used. Thereby, the temperature range can be changed finely and a thermal image following the temperature change of the object 2 can be displayed. Further, the first or second temperature range may not be automatically switched inside the apparatus, but the first or second temperature range may be switched by a user's manual operation.

  Further, although each storage unit is shown as a separate block, the function of each storage unit may be realized by preparing one memory and logically dividing the area of this memory into a predetermined size. By configuring the memory in this way, it is possible to reduce the number of components mounted on the image processing unit 10 and to improve the fault tolerance.

  An alarm device may be provided instead of the display device 5. This alarm device issues an alarm based on the image data output from the reading unit 19 when the maximum temperature of the object is less than a predetermined threshold value or more than a predetermined threshold value. For example, when the maximum temperature of the object 2 corresponds to either the first or second temperature range, the alarm device may issue an alarm by voice or the like.

  The series of processes in the above-described embodiment can be executed by hardware, but can also be executed by software. When a series of processing is executed by software, it is possible to execute various functions by installing programs that make up the software into a computer built into dedicated hardware, or by installing various programs. It is. For example, what is necessary is just to install and run the program which comprises desired software in a general purpose personal computer.

  Further, a recording medium on which a program code of software that realizes the functions of the above-described embodiments may be supplied to the system or apparatus. It goes without saying that the function is also realized by a computer (or a control device such as a CPU) of the system or apparatus reading and executing the program code stored in the recording medium.

  As a recording medium for supplying the program code in this case, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like is used. Can do.

  Further, the functions of the above-described embodiment are realized by executing the program code read by the computer. In addition, based on the instruction of the program code, the OS running on the computer performs part or all of the actual processing. The case where the functions of the above-described embodiment are realized by the processing is also included.

  Further, the present invention is not limited to the above-described embodiment, and it is needless to say that various other configurations can be taken without departing from the gist of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Thermography apparatus, 2 ... Object, 3 ... Lens, 4 ... Infrared sensor, 5 ... Display apparatus, 10 ... Image processing part, 11 ... Sensor control part, 12 ... Signal processing part, 12a ... Addition / average part, DESCRIPTION OF SYMBOLS 13 ... Clock output part, 14a ... 1st integration time storage part, 14b ... 2nd integration time storage part, 15a ... 1st offset data storage part, 15b ... 2nd offset data storage part, 16a, 16b ... Timing, 17 ... temperature range detector, 18 ... writer, 19 ... reader, 20a ... first image storage, 20b ... second image storage

Claims (7)

A first temperature range that is set when a maximum temperature of the object is less than a predetermined threshold among a temperature range including a temperature range from a minimum temperature to a maximum temperature of the object, and a maximum of the object Switching to a second temperature range different from the first temperature range, which is set when the temperature is equal to or higher than a predetermined threshold, at a predetermined timing, and depending on the intensity of infrared light emitted from the object A sensor control unit that supplies information about the switched first or second temperature range to an infrared sensor that outputs an image signal;
A signal processing unit that adds and averages the image signals output from the infrared sensor over a predetermined period based on information about the first or second temperature range supplied by switching from the sensor control unit at the predetermined timing; ,
A writing unit for writing image data obtained from the processed image signal output from the signal processing unit to the image storage unit for each of the first or second temperature ranges switched by the sensor control unit;
From the image data, a temperature range detector that detects a temperature range of the object and selects the first or second temperature range according to the temperature range of the object;
The image data written in either the first or second temperature range is read from the image storage unit and output in accordance with the first or second temperature range selected by the temperature range detection unit. A thermographic device comprising: a reading unit; The information related to the first temperature range is used as a pair of a first integration time for integrating the image signal and the first integration time, and the infrared sensor is offset in accordance with the first integration time. First offset data to be included,
The information about the second temperature range is used as a pair of a second integration time for integrating the image signal and the second integration time, and the infrared sensor is offset in accordance with the second integration time. The thermography apparatus according to claim 1, wherein second offset data is included. The sensor control unit sets the first or second integration time to the infrared sensor, and waits for stabilization,
The thermography apparatus according to claim 1, wherein the signal processing unit adds and averages the image signal output from the infrared sensor every predetermined number of frames. The thermography apparatus according to claim 1, further comprising a display unit that displays a thermal image of the object based on the image data received from the reading unit. Furthermore, when the temperature range of the said object becomes less than the said predetermined threshold value or more than the said predetermined threshold value, the alarm part which issues an alarm based on the said image data output from the said reading part is provided. The thermography apparatus of any one of these. A first temperature range that is set when a maximum temperature of the object is less than a predetermined threshold among a temperature range including a temperature range from a minimum temperature to a maximum temperature of the object, and a maximum of the object Switching to a second temperature range different from the first temperature range, which is set when the temperature is equal to or higher than a predetermined threshold, at a predetermined timing, and depending on the intensity of infrared light emitted from the object Supplying information relating to the switched first or second temperature range to an infrared sensor that outputs an image signal,
Based on information on the first or second temperature range supplied by switching at the predetermined timing, the image signal output from the infrared sensor is averaged over a predetermined period; and
Writing image data obtained from the averaged image signal into the image storage unit for each of the first or second temperature ranges switched at the predetermined timing;
Detecting a temperature range of the object from the image data, and selecting the first or second temperature range according to the temperature range of the object;
And reading and outputting the image data written in either the first or second temperature range from the image storage unit in accordance with the selected first or second temperature range. Processing method. A first temperature range that is set when a maximum temperature of the object is less than a predetermined threshold among a temperature range including a temperature range from a minimum temperature to a maximum temperature of the object, and a maximum of the object Switching to a second temperature range different from the first temperature range, which is set when the temperature is equal to or higher than a predetermined threshold, at a predetermined timing, and depending on the intensity of infrared light emitted from the object A procedure for supplying information relating to the switched first or second temperature range to an infrared sensor that outputs an image signal,
A procedure of averaging the image signals output from the infrared sensor over a predetermined period based on information on the first or second temperature range supplied by switching at the predetermined timing.
A procedure for writing image data obtained from the image signal averaged for each of the first or second temperature ranges switched at the predetermined timing to an image storage unit,
Detecting the temperature range of the object from the image data, and selecting the first or second temperature range according to the temperature range of the object;
A procedure for reading out and outputting the image data written in either the first or second temperature range from the image storage unit in accordance with the selected first or second temperature range, to a computer A program to be executed.

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