JP2011149834A - Infrared temperature measuring device - Google Patents

Abstract

An infrared temperature measurement device capable of locally correcting a temperature measurement error due to a reflection component caused by a surface shape of a measurement object.
An infrared temperature measurement device 10 includes a temperature distribution calculation unit 30 that calculates a temperature distribution of a measurement object D from infrared energy and visible light, and an image generation unit that generates a visible light image from visible light. A luminance value that is larger than the reference luminance value, and a reference luminance value calculation unit that calculates the luminance value of the luminance value of each pixel of the visible light image and calculates the luminance value that is the peak of the frequency of the frequency distribution as the reference luminance value A pixel extraction unit that extracts pixels of a visible light image, a luminance ratio calculation unit that calculates the ratio of the reference luminance value to the luminance value of the extracted pixel as a luminance ratio, assigns a luminance ratio to the extracted pixels, and luminance to other pixels A mask generation unit that creates a mask by assigning 1 as a ratio, and a temperature correction unit that corrects the temperature of each pixel of the infrared image by multiplying the temperature of each pixel of the infrared image by the luminance ratio using the mask.
[Selection] Figure 1

Description

  The present invention relates to an infrared temperature measurement device that detects infrared energy emitted from a measurement object, converts the energy into temperature, and displays the temperature distribution of the measurement object as an image, and more particularly, infrared radiation emitted from the measurement object. The present invention relates to an infrared temperature measuring apparatus capable of suitably correcting the reflected energy component of the infrared ray.

  Conventionally, in various fields including engineering and medicine, thermography is used to measure the surface temperature of a measurement object in a non-contact manner. Thermography is a method of representing the temperature distribution on the surface of an object or a living body as an image.

  Specifically, an infrared temperature measuring device using thermography generally detects infrared energy from a measurement object, converts it to a temperature corresponding to the detected energy amount (the magnitude of energy), An infrared image representing the distribution of the converted temperature is generated and displayed.

  By using such an infrared temperature measurement device, not only can the surface temperature of the measurement object be measured in a non-contact manner, but also the temperature (temperature distribution) of a predetermined region of the measurement object surface can be measured in real time. it can.

  However, the temperature distribution measured by the infrared temperature measuring device largely fluctuates depending on the movement of the measurement object and the surrounding temperature, resulting in poor measurement accuracy. Considering this point, for example, considering the influence of the movement of the measurement object, specify the part to be corrected based on the change in the histogram of the image captured by the infrared camera, and then correct the infrared image An infrared temperature measuring device has been proposed (see, for example, Patent Document 1).

  On the other hand, in the following cases, the measurement accuracy by the infrared temperature measuring device may be inferior. Specifically, as shown in FIG. 7A, when the measurement object D is heated by the infrared heater H, infrared rays from the infrared heater H are applied to the measurement object D as shown in FIG. Absorbed. The measurement object D is heated by the absorbed infrared rays (energy), and infrared rays are emitted from the measurement object. On the other hand, a part of infrared rays (energy) from the infrared heater H is reflected on the surface of the measurement object D without being absorbed by the measurement object D.

  The infrared temperature measuring device (infrared camera) 90 detects infrared energy in which the radiated infrared energy (radiation component) and the infrared energy reflected from the surface (reflection component) are mixed, and the infrared energy The magnitude is converted into temperature, and the temperature distribution of the measuring object D is measured from the converted temperature.

  However, the infrared energy that should be detected by the infrared temperature measuring device 90 is only the radiation component that is the temperature information of the object to be measured, and an error occurs in the measured temperature due to the ultraviolet energy of the reflection component that is a disturbance. As a result, the measurement accuracy is inferior to that of a contact-type temperature measuring device.

  In view of such points, for example, a standard sample with a known reflectance of visible light is placed in the imaging range of the infrared temperature measuring device, and infrared light is measured based on infrared signals from the measurement object and the standard sample. An infrared temperature measuring device that corrects the reflection level of light is proposed (see, for example, Patent Document 2).

JP 2001-154646 A Japanese Examined Patent Publication No. 7-72702

  However, the infrared temperature measuring device shown in Patent Document 1 uses a histogram to weight and correct an infrared image in order to improve detection accuracy, but this histogram is measured on the surface of the measurement object. Since the influence of infrared reflection is not taken into consideration, this is not removed, and therefore the temperature measurement accuracy is inferior particularly when the reflection component of the measurement object is large.

  In addition, since the infrared temperature measuring device shown in Patent Document 2 has a measurement object to be corrected and a standard sample to be a correction reference as separate bodies, the correction is performed when the measurement accuracy is to be increased. The shapes of possible measurement objects are limited.

  That is, the reflectance of radiation changes depending on the surface shape of the measurement object, and in order to improve the measurement accuracy, it is necessary to manufacture a standard sample that imitates the shape of the measurement object. In particular, when the shape of the measurement object is complicated, the reflectance of the standard sample that imitates the measurement object cannot be uniquely defined. And even if temperature correction is performed on such an object to be measured, it becomes an all-over temperature correction and may be corrected in a direction deviating from the correctly measured value. .

  The present invention has been made in view of these points, and an object of the present invention is to provide an infrared ray capable of correcting a local temperature measurement error due to a reflection component caused by the surface shape of a measurement object. The object is to provide a temperature measuring device.

  As a result of intensive studies in view of the above problems, the inventor has found that the portion of the pixel of the visible light image that exceeds the peak value (maximum value) of the histogram of the luminance value is the luminance value and the infrared energy. If the temperature measured using the luminance value of the peak value of the histogram is corrected, the measurement error that occurs locally due to the reflected component of infrared energy can be reduced. And gained new knowledge.

  The present invention is based on the inventor's new knowledge, and an infrared temperature measurement device according to the present invention includes an infrared detector that detects infrared energy from a measurement object, and visible light from the measurement object. An infrared temperature measurement device comprising a visible light detector for detecting a temperature distribution and a temperature distribution calculation unit for calculating a temperature distribution of the measurement object from detected infrared energy and visible light, the temperature distribution calculation unit comprising: The infrared energy is converted into a temperature corresponding to the infrared energy to generate an infrared image representing the temperature distribution of the measurement object, and a visible light image having the same resolution as the infrared image is generated from the visible light. A reference luminance for calculating a frequency distribution of luminance values of each pixel of the visible light image, and calculating a luminance value at the peak of the frequency distribution as a reference luminance value A calculation unit; a pixel extraction unit that extracts pixels of a visible light image having a luminance value greater than the reference luminance value; and a luminance ratio that calculates a ratio of the reference luminance value to the luminance value of the extracted pixel as a luminance ratio An arithmetic unit, a mask generation unit that assigns the luminance ratio to the extracted pixels, assigns 1 as the luminance ratio to the other pixels, and generates a mask of the luminance ratio, and uses the mask, A temperature correction unit that corrects the temperature of each pixel of the infrared image by multiplying the temperature of each pixel by the luminance ratio corresponding to the pixel;

  According to the present invention, first, a visible light image is generated from the detected visible light by the image generation unit. Next, the reference luminance value calculation unit calculates the frequency distribution (histogram) using the luminance value of each pixel of the visible light image, and sets the luminance value that maximizes the frequency as the reference luminance value. Then, using this reference luminance value as a reference, the pixel extraction unit extracts pixels (coordinates) of the visible light image having a luminance value larger than the reference luminance value. This extracted pixel is a pixel representing a portion where a large number of reflection components requiring correction are detected.

  Next, the ratio of the reference brightness value to the brightness value of the extracted pixel (0 <reference brightness ratio / the brightness ratio of the extracted pixel <1) is extracted for each extracted pixel by the brightness ratio calculation unit. Calculate to Then, in the mask generation unit, the calculated luminance ratio is assigned to the pixel (extracted pixel) of the visible light image having a luminance value larger than the reference luminance value, and other unextracted pixels (that is, the reference pixel) For a pixel of a visible light image having a luminance value equal to or lower than the luminance value, a luminance ratio of 1 is assigned as a luminance ratio, and an image of the luminance ratio to which this luminance ratio is assigned is used as a mask. As a result, the portion having the luminance ratio of 1 is estimated to have no infrared energy reflection component and is not corrected (temperature correction amount = 0). As the luminance ratio decreases from 1, the infrared energy reflection component of that portion is reduced. Therefore, it is possible to obtain a mask with a reflection weight that estimates that is large and increases the temperature correction amount.

  On the other hand, the image generation unit converts the infrared energy into a temperature corresponding to the infrared energy, and generates an infrared image representing the temperature distribution of the measurement object. This infrared image has the same resolution as the visible light image (mask) described above.

  Then, the temperature correction unit uses the mask to correct the temperature of the infrared image by multiplying the temperature of the pixel at each coordinate of the infrared image by the luminance ratio of the corresponding pixel (the pixel at the same coordinate). To do. In this way, even if the measurement object has a complicated surface shape, the temperature measurement error due to the reflection component caused by the surface shape of the measurement object can be locally corrected.

  The infrared temperature measuring device according to the present invention more preferably includes a light source for irradiating the measurement object with visible light when detecting visible light from the measurement object. According to the present invention, by using this light source, it is possible to obtain a visible light image in which a portion where the influence of the reflection of visible light is large is emphasized, and the reflection component of infrared energy caused by the surface shape of the measurement object is further increased. It is possible to detect with high accuracy, and thereby it is possible to perform more accurate temperature correction.

  In the infrared temperature measurement device according to the present invention, it is more preferable that the temperature correction unit includes a matching processing calculation unit that performs a matching process on the visible light image and the infrared image. According to the present invention, the matching processing of the two images is performed so that the shape of the measurement object in the visible light image matches the shape of the measurement object in the infrared image by this matching processing. It is possible to correct deviations and perform more accurate correction. This matching process is a generally known matching process such as a pattern matching process, a template matching process, or a block matching process. This matching process may be performed on a mask obtained from a visible light image. The processing method is not particularly limited as long as the shape of the measurement object in the visible light image and the shape of the measurement object in the infrared image can be more accurately matched.

  Furthermore, it is preferable that the infrared temperature measuring device according to the present invention includes a storage unit that stores the infrared detector and the visible light detector in a replaceable manner. According to the present invention, in the storage unit, these are replaced to generate the respective images, so that an infrared image having the same angle of view (that is, taken at the same angle) and a visible light image can be generated. it can. If a mask obtained from such a visible light image is used, the temperature of the infrared image corresponding to this position can be corrected at a pixel at an appropriate position (coordinates).

  According to the present invention, it is possible to correct a local temperature measurement error due to a reflection component caused by a surface shape of a measurement target with respect to an image representing a temperature distribution obtained by infrared energy from the measurement target. it can.

1 is an overall configuration diagram of an infrared temperature measurement device according to an embodiment of the present invention. FIG. 2 is an arithmetic block diagram of the arithmetic device shown in FIG. 1. It is a conceptual diagram for demonstrating the calculation process of each part of the calculation block of FIG. 2, (a) is a conceptual diagram of the luminance value of each pixel of the visible light image memorize | stored in the visible light image data memory | storage part. , (B) is a conceptual diagram showing a histogram of luminance values performed by the reference luminance value calculation unit, (c) is a conceptual diagram for explaining extraction of the pixel extraction unit, and (d) is a diagram of the mask generation unit (E) is a conceptual diagram of an infrared image representing the temperature of each pixel of the infrared image, (f) is a conceptual diagram of the pixel shown in (e) using the mask shown in (d). The conceptual diagram of the infrared image after correction | amendment when correct | amending measurement temperature. The calculation flow figure for demonstrating the calculation method of the reflective partial mask production | generation part of the infrared temperature measuring apparatus shown in FIG. The calculation flow figure for demonstrating the calculation method of the temperature distribution correction | amendment part of the infrared temperature measuring apparatus shown in FIG. (A) is a figure for demonstrating the imaging | photography state of the measurement object in a visible light detector, (b) is the visible light image figure image | photographed by (a), (c) is a visible light image. The figure which showed frequency distribution of each pixel, (d) is the figure which showed the mask of the luminance ratio computed from the visible light image, (e) is for demonstrating the imaging | photography state of the measuring object in an infrared detector (F) is an infrared image taken by (e), (h) is an infrared image obtained by correcting the infrared image of (e) with the mask of (d), and (h) is a weight. The infrared image figure when the correction | amendment which does not attach is performed. It is a figure for demonstrating the measuring method of the temperature using the infrared temperature measuring apparatus until now, (a) is a figure for demonstrating a measurement state, (b) is for demonstrating the detail of a temperature measurement. Illustration.

  Hereinafter, embodiments of an infrared temperature measuring device according to the present invention will be described in detail with reference to the following drawings.

  FIG. 1 is an overall configuration diagram of an infrared temperature measuring apparatus according to an embodiment of the present invention. As shown in FIG. 1, an infrared temperature measuring apparatus 10 according to the present invention detects infrared energy emitted from a measurement object D, converts the infrared energy into a temperature corresponding to the energy, and measures the measurement object D. The temperature distribution is displayed as an infrared image.

  The infrared temperature measuring device 10 is calculated by a camera body 20 that images the measurement object D, and a calculation device (temperature distribution calculation unit) 30 that calculates the temperature distribution of the measurement object D based on the captured information. And a display device 70 that displays the temperature distribution of the measurement object as an image.

  The camera body 20 includes an infrared detector 23 and a visible light detector 24. The infrared detector 23 is a device that detects infrared energy from the measurement object D, and corresponds to, for example, an infrared energy detection portion of thermography. The infrared detector 23 includes a semiconductor element such as a CCD, and infrared rays are detected by the semiconductor element via a lens.

  The visible light detector 24 detects visible light from the measurement object, and includes a semiconductor element such as a CCD. The visible light is detected by the semiconductor element via a lens. The visible light detector 24 corresponds to a detection part such as a so-called visible light camera.

  Such an infrared detector 23 and visible light detector 24 are accommodated in the accommodating portion 21 so as to be interchangeable. Specifically, the storage unit 21 captures (detects) the infrared image obtained from the infrared detector 23 and the visible light image obtained from the visible light detector 24 at the same angle of view (at the same angle). The infrared detector 23 and the visible light detector 24 can be interchanged.

  Further, the storage unit 21 is supported by the gantry 26, and when the visible light detector 24 is set in the storage unit 21 on the distal end side (imaging direction side) of the storage unit 21, the measurement object D is placed. A light source 28 for irradiating is attached. The camera body 20 is also provided with an imaging condition adjustment unit 29 for adjusting the focus with the measurement object D and adjusting the exposure.

  When the apparatus is used, the visible light detector 24 is set in the storage unit 21, the photographing condition adjustment unit 29 adjusts the photographing condition, the visible light detector 24 detects visible light, and the detection signal is output to the arithmetic unit 30. To do. After the output, the visible light detector 24 is removed from the storage unit 21, the infrared detector 23 is set in the storage unit 21, the infrared energy is detected by the infrared detector 23, and the signal is output to the arithmetic device 30. Thereby, the infrared energy and visible light of the measuring object D can be detected at the same angle.

  The computing device 30 computes the temperature distribution of the measuring object D based on the visible light detection signal output from the visible light detector 24 and the detection signal detected by the infrared detector 23. A memory such as a ROM and a RAM for storing data based on the detection signal and a CPU for calculating the temperature distribution of the measurement object D from the data stored in the storage device are provided.

  The temperature distribution of the measurement object D calculated by the calculation device 30 is output to the display device 70 as an output signal. The display device 70 outputs a color corresponding to the temperature from each pixel, and as a result, displays an image of the temperature distribution of the measurement object D.

  FIG. 2 shows a calculation block diagram of the calculation device 30, FIG. 3 is a conceptual diagram for explaining calculation processing of each part of the calculation block of FIG. 2, and (a) shows visible light image data. It is a conceptual diagram of the luminance value of each pixel of the visible light image memorize | stored in the memory | storage part, (b) is a conceptual diagram which showed the histogram of the luminance value which a reference | standard luminance value calculating part performs, (c) is pixel extraction. (D) is a conceptual diagram of a mask generated by the mask generating unit, (e) is a conceptual diagram of an infrared image representing the temperature of each pixel of the infrared image, (f) () Is a conceptual diagram of an infrared image after correction when the measurement temperature of each pixel shown in (e) is corrected using the mask shown in (d).

  As shown in FIG. 2, the arithmetic device (temperature distribution calculation unit) 30 configured by the hardware described above includes, as software, an image generation / transmission unit 40, a reflection partial mask generation unit 50, and a temperature distribution correction unit 60. And at least.

  The image generation / transmission unit 40 includes an image generation unit 41 and an image data transmission unit 42, and the image generation unit 41 converts the infrared energy detected by the infrared detector 23 into temperature, and An infrared image representing the temperature distribution is generated, and a visible light image having the same resolution (number of pixels) as the infrared image is generated from the visible light detected by the visible light detector 24.

  The obtained infrared image and visible light image are output to the image data transmission unit 42. The image data transmission unit 42 transmits the input infrared image to the temperature distribution correction unit 60 and transmits the visible light image to the reflection partial mask generation unit 50. Here, since the infrared detector 23 and the visible light detector 24 can be interchanged with respect to the storage unit 21, after each detector is set, according to the set detector, The image data transmission unit 42 selectively transmits the image to storage units 51 and 61 described later.

  When the luminance value of each pixel obtained by the visible light image becomes a luminance value exceeding the peak of the histogram, the reflection partial mask generation unit 50, the luminance value, the amount of the reflection component of infrared energy, Is a means for performing masking processing (correction) on an infrared image at a temperature correction rate (temperature correction amount) corresponding to a luminance value equal to or higher than the peak value of the histogram.

  Specifically, the reflective partial mask generation unit 50 includes a visible light image data storage unit 51, a reference luminance value calculation unit 52, a pixel extraction unit 53, a luminance ratio calculation unit 54, and a mask generation unit 55. At least.

  The visible light image data storage unit 51 stores the visible light image transmitted from the image data transmission unit 42 in order to generate a mask for performing the masking process. As shown in FIG. 3A, the pixel at each coordinate of the stored visible light image has luminance value information.

  Next, the reference luminance value calculation unit 52 uses the stored luminance value of each pixel of the visible light image to generate a frequency distribution (histogram) of the luminance value of the visible light image, as shown in FIG. The luminance value that is the frequency peak (maximum value) of the frequency distribution is calculated as the reference luminance value. For example, as shown in FIG. 3B, in the case of the calculated histogram, the peak has a luminance of 200, so the reference luminance value is 200.

  Next, the pixel extraction unit 53 extracts pixels (coordinates) of the visible light image having a luminance value larger than the reference luminance value based on the stored visible light image. That is, the pixel extraction unit 53 estimates and extracts pixels (coordinates) that are greatly affected by the reflection of infrared energy proportional to the luminance of visible light. For example, when the reference luminance value is 200 as shown in FIG. 3B, the pixels marked with ● shown in FIG. 3C are extracted pixels.

  The luminance ratio calculation unit 54 calculates the ratio of the reference luminance value to the luminance value of the pixel at each coordinate extracted by the pixel extraction unit 53 as a luminance ratio (reference luminance ratio / extracted pixel luminance ratio). The calculated luminance ratio is in the range of 0 <luminance ratio <1.

  The mask generation unit 55 assigns the brightness ratio calculated so as to correspond to the extracted pixel, assigns 1 as the brightness ratio to the other pixels, and creates a mask for the brightness ratio. For example, as shown in FIG. 3D, when the reference luminance value is 200 and the extracted pixel has a luminance value of 240, the luminance ratio is 0.8, and the extracted pixel has a luminance ratio of 230. In some cases, the luminance ratio is 0.9. Here, the calculation is performed up to the first digit of the decimal point, but the calculation may be performed up to the number of digits less than that.

  In this way, the mask for temperature correction is weighted (a correction amount is set for each coordinate pixel). That is, according to this mask, when the luminance ratio is 1, there is no infrared energy reflection component and no correction is performed (temperature correction amount = 0), and the infrared energy reflection component decreases as the luminance ratio decreases from 1. Can be estimated and the temperature correction amount can be increased.

  The temperature distribution correction unit 60 performs temperature correction using the created mask. Specifically, the temperature distribution correction unit 60 includes an infrared image data storage unit 61, a cross-correlation function calculation unit 62, and a temperature correction unit 63.

  The infrared image data storage unit 61 stores the infrared image transmitted from the image data transmission unit 42. As shown in FIG. 3 (e), the infrared image is an image including temperature data in each pixel corresponding to a photographed position by converting infrared energy into a temperature corresponding to the energy, that is, a temperature distribution. This is a thermal image. Then, the cross-correlation function calculation unit (matching processing calculation unit) 62 calculates a cross-correlation function between the visible light image (or the produced mask) and the infrared image, thereby measuring the measurement target of the infrared image and the mask. Perform pattern matching of object shape. Thereby, a masking process (correction) can be performed on a pixel at an appropriate position of the infrared image.

  Note that the infrared image may be converted so that the measurement object of the infrared image matches the measurement object of the mask, or the measurement object of the mask with respect to the measurement object of the infrared image. However, you may convert an infrared image so that it may correspond. As another aspect, the cross-correlation function may be calculated in the image data transmission unit 42 so as to perform pattern matching of the shape of the measurement object between the visible light image and the infrared image. In addition, as shown in the calculation flow described later, only the cross-correlation function is calculated in the cross-correlation function calculation unit (matching processing calculation unit), and using this cross-correlation function, the position where the mask and the infrared image most closely match Temperature correction may be performed.

  After the matching process, the temperature correcting unit 63 uses the mask to multiply the temperature of each pixel of the infrared image by the brightness ratio corresponding to this pixel (of the mask having the same coordinates), thereby Correct the pixel temperature. Specifically, the temperature of each pixel of the infrared image shown in FIG. 3E is multiplied by the brightness ratio of the mask shown in FIG. 3D, and the image of the temperature distribution shown in FIG. Obtainable. 3F is displayed on the display device 70 as an image to which a color corresponding to the temperature is assigned instead of the temperature value itself.

  Next, a temperature measurement method using the above-described infrared temperature measurement device 10 will be described with reference to FIGS. FIG. 4 is a calculation flow diagram for explaining a calculation method of the reflection partial mask generation unit of the infrared temperature measurement apparatus shown in FIG. 2, and FIG. 5 shows a temperature distribution correction unit of the infrared temperature measurement apparatus shown in FIG. It is a calculation flow figure for demonstrating the calculation method.

  FIG. 6 is a diagram for explaining a part of the flow in the calculation flow shown in FIG. 3 and FIG. 4, and (a) is for explaining the imaging state of the measurement object with the visible light detector. The figure of (b) is the visible light image figure image | photographed by (a), (c) is the figure which showed the frequency distribution of each pixel of a visible light image, (d) was computed from the visible light image The figure which showed the mask of a luminance ratio, (e) is a figure for demonstrating the imaging | photography state of the measuring object in an infrared detector, (f) is the infrared image figure image | photographed by (e), (g) (A) is an infrared image diagram obtained by correcting the infrared image of (e) with the mask of (d), and (h) is an infrared image diagram when correction without weighting is performed.

  First, in step S301, the visible light detector 24 is set in the storage unit 21 of the camera body 20. Next, proceeding to step S302, the photographing condition adjusting unit 29 sets photographing conditions, and the process proceeds to step S303. In step S303, the light source 28 is turned on (ON) and the measurement object D is irradiated.

  Next, in step S304, as shown in FIG. 6A, the visible light from the measurement object D is detected using the visible light detector 24, and the measurement object D is photographed. Here, by using the light source 28 to reflect the light from the light source 28 on the surface of the irradiated measurement object D, it is possible to more accurately detect a portion to be corrected that is greatly influenced by the reflected component of infrared rays. Can do.

  In step S305, the image generation unit 41 generates a visible light image in FIG. 6B based on the signal from the visible light detector 24. This visible light image is generated as an image having the same resolution (the same number of vertical and horizontal pixels) as an infrared image described later. In step S <b> 306, the generated visible light image is transmitted to the reflection partial mask generation unit 50 by the image data transmission unit 42. In step S307, the visible light image data storage unit 51 stores (saves) the visible light image transmitted from the image data transmission unit 42 in the memory.

  In step S308, the reference luminance value calculation unit 52 calculates the luminance value of the pixel located at each coordinate of the image based on the stored visible light image, and as shown in FIG. The frequency distribution (histogram) of the luminance value of each pixel is calculated (created). Further, in step S309, as shown in FIG. 6C, a luminance value (reference luminance value) that becomes the frequency peak value (histogram median (median)) of the frequency distribution is calculated.

  In step S310, the pixel extraction unit 53 extracts pixels (coordinates) of the visible light image having a luminance value larger than the reference luminance value based on the stored visible light image (detects specific coordinates). In step S311, the luminance ratio calculation unit 54 calculates the ratio of the reference luminance value to the luminance value of each pixel (coordinate) extracted by the pixel extraction unit 53 as the luminance ratio.

  In step S312, the mask generation unit 55 assigns a luminance ratio corresponding to the extracted pixel and assigns 1 as the luminance ratio to the other pixels as shown in FIG. Create As a result, a reflection level weighting mask is generated.

  Next, the calculation flow of the temperature distribution correction shown in FIG. 5 is shown below. First, in step S401, the infrared detector 23 is set in the storage unit 21 of the camera body 20. Next, proceeding to step S402, the photographing condition adjusting unit 29 sets the photographing condition, and the process proceeds to step S403. Next, in step S403, as shown in FIG. 6E, infrared energy from the measurement object D is detected using the infrared detector 23 (the measurement object D is photographed).

  In step S404, the image generation unit 41 generates an infrared image based on the signal from the infrared detector 23 as shown in FIG. The infrared image is generated with the same number of pixels (the same number of vertical and horizontal pixels) as the visible light image described above. In step S <b> 405, the generated infrared image is transmitted to the infrared image data storage unit 61 of the temperature distribution correction unit 60 by the image data transmission unit 42.

  In step S406, the infrared image data storage unit 61 stores (saves) the transmitted infrared image in a memory. In step S407, the cross-correlation function calculator 62 calculates a cross-correlation function between the stored infrared image, the mask generated from the visible light image, and the infrared image.

  In step S408, using the cross-correlation function calculated by the temperature correction unit 63, the temperature of each pixel of the infrared image as shown in FIG. Is multiplied by a reflection weight mask of luminance ratio corresponding to the pixel as shown in FIG. 6D, thereby correcting the temperature of each pixel of the infrared image as shown in FIG.

  Thereby, it can correct | amend in the position where the shape of the measuring object of two images most agrees. As a result, unlike the infrared image that has been corrected without weighting as shown in FIG. 6 (h), it is assumed that the reflection from the measurement object is strong in the infrared image as shown in FIG. 6 (g). Only the part to be applied can be corrected locally.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various designs can be made without departing from the spirit of the present invention described in the claims. It can be changed. For example, in the present embodiment, the infrared detector and the visible light detector can be interchanged. However, as long as the accuracy of the matching process can be increased, both of them may be provided in the camera body.

10: Infrared temperature measuring device, 20: Camera body, 21: Storage unit, 23: Infrared detector, 24: Visible light detector, 26: Mount, 28: Light source, 29: Imaging condition adjusting unit, 30: Arithmetic unit, 40: Image generation / transmission unit, 41: Image generation unit, 42: Image data transmission unit, 50: Reflection partial mask generation unit, 51: Visible light image data storage unit, 52: Reference luminance value calculation unit, 53: Pixel extraction unit , 54: luminance ratio calculation unit, 55: mask generation unit, 60: temperature distribution correction unit, 61: infrared image data storage unit, 62: cross-correlation function calculation unit, 63: temperature correction unit, 70: display device, D: Measurement object

Claims (4)

An infrared detector for detecting infrared energy from the measurement object, a visible light detector for detecting visible light from the measurement object, and a temperature distribution of the measurement object from the detected infrared energy and visible light. An infrared temperature measurement device having a temperature distribution calculation unit for calculating,
The temperature distribution calculation unit converts the infrared energy into a temperature corresponding to the infrared energy to generate an infrared image representing a temperature distribution of the measurement object, and from the visible light to the infrared image and An image generator that generates a visible light image of the same resolution;
A reference luminance value calculation unit that calculates a frequency distribution of luminance values of each pixel of the visible light image and calculates a luminance value that is a peak of the frequency of the frequency distribution as a reference luminance value;
A pixel extraction unit that extracts pixels of a visible light image having a luminance value larger than the reference luminance value;
A luminance ratio calculation unit that calculates a ratio of the reference luminance value to the luminance value of the extracted pixel as a luminance ratio;
A mask generation unit that assigns the brightness ratio to the extracted pixels and assigns 1 to the other pixels as a brightness ratio, and generates a mask of the brightness ratio;
Using the mask, a temperature correction unit that corrects the temperature of each pixel of the infrared image by multiplying the temperature of each pixel of the infrared image by the luminance ratio corresponding to the pixel;
An infrared temperature measuring device comprising:   The infrared temperature measuring apparatus according to claim 1, further comprising a light source for irradiating the measurement object with visible light.   The infrared temperature measurement apparatus according to claim 1, wherein the temperature correction unit includes a matching processing calculation unit that performs a matching process on the visible light image and the infrared image.   The infrared temperature measurement device according to any one of claims 1 to 3, wherein the infrared temperature measurement device includes a storage unit that stores the infrared detector and the visible light detector in a replaceable manner. .

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