JP3148869U - Radiation thermometer - Google Patents

Abstract

【Task】
The light incident from the incident optical system is received by the image sensor and the infrared sensor without using an optical branching device such as a prism, thereby shortening the distance between the incident optical system and each element and reducing the size of the entire apparatus.
[Solution]
A radiation thermometer (1) that measures the temperature of the object to be measured by condensing the infrared ray radiated from the surface of the object to be measured on the infrared sensor (3) by the condenser lens (4) and converting the amount of the infrared rays into temperature. ), The imaging camera (5) for imaging the object to be measured has its imaging optical axis (Z ₅ ) aligned with the infrared measurement optical axis (Z ₄ ) from the object to be measured toward the condenser lens (4). It is embedded in the central part of the condenser lens (4).
[Selection] Figure 1

Description

  The present invention condenses infrared rays emitted from the surface of the object to be measured by a condenser lens, measures the amount of infrared rays in a non-contact manner by an infrared sensor, and measures the temperature of the object by converting the temperature. Related to thermometer.

A radiation thermometer has an infrared sensor such as a thermopile or pyroelectric element at the condensing position of a condensing lens. The infrared thermometer collects infrared radiation emitted from the object to be measured, and an infrared signal is sent to the infrared sensor. And measure the temperature.
In this case, a camera equipped with an imaging camera has been proposed so that the temperature measurement state / measurement location can be confirmed later with an image.

For this reason, the radiation thermometer 41 shown in FIG. 6 arranges a thermopile 43 as an infrared sensor on the infrared measurement optical axis Xin collected by the condenser lens 42, and between the condenser lens 42 and the thermopile 43. A part of the light is branched by the arranged prism 44, and the imaging element 45 is arranged on the branched optical axis Xd.
JP 2003-270049 A

  According to this, since the image signal output from the image sensor 45 is displayed on the liquid crystal panel 48 via the image processing device 46 -the liquid crystal driving device 47, the temperature measurement region can be confirmed on the image. In addition, the surface temperature of the object to be measured can be displayed on the liquid crystal panel 48 by converting the amount of infrared rays detected by the thermopile 43 by the temperature measuring unit 49.

  However, in this case, since the prism 44 must be disposed between the condenser lens 42 and the thermopile 43, there is a problem that the distance from the condenser lens 42 to the thermopile 43 becomes long and the casing becomes large.

  Therefore, the present invention guides the infrared light emitted from the non-measurement object to the infrared sensor and at the same time guides the visible light to the imaging camera without arranging a light splitter such as a prism between the condenser lens and the infrared sensor. Therefore, it is a technical problem to make it possible to downsize the entire apparatus by shortening the distance from the condenser lens to the infrared sensor.

  In order to solve this problem, the present invention condenses the infrared ray emitted from the surface of the object to be measured on the infrared sensor by the condenser lens, and measures the temperature of the object to be measured by converting the amount of the infrared ray into the temperature. In the radiation thermometer, the imaging camera for imaging the object to be measured is embedded in the central portion of the condenser lens so that the imaging optical axis coincides with the infrared measurement optical axis from the object to be measured to the condenser lens. It is characterized by that.

In the radiation thermometer of the present invention, an imaging camera for imaging the object to be measured is embedded in the central portion of the condenser lens, and its imaging optical axis coincides with the infrared measurement optical axis from the object to be measured to the condenser lens. Therefore, when measuring the temperature of non-measurement objects, the measurement optical axis is located at the center of the image captured by the imaging camera, and by checking the image, it is estimated where the temperature is being measured. be able to.
In addition, since the imaging camera is embedded in the condenser lens, there is no need to provide a prism between the condenser lens and the infrared sensor, and as a result, the distance can be shortened, and the entire device can be made compact. Can be

  At this time, as described in claim 2, among the many temperature sensing elements arranged on the light receiving surface of the infrared sensor, the temperature sensing element arranged in the shadowed portion of the imaging camera controls the temperature of the imaging element. Since there is a possibility of detection, the measurement accuracy is not lowered by measuring the temperature with a temperature sensing element arranged around the shadowed portion of the imaging camera.

  According to the third aspect of the present invention, when an index indicating the position of the measurement optical axis is displayed on the display that displays the image of the imaging camera, the optical axis position is confirmed by looking at the display. It is possible to remove the temperature measurement point.

As described in claim 4, if the optical design is such that the viewing angle of the infrared light beam incident on the condenser lens is equal to the viewing angle of the imaging camera,

According to the fifth aspect of the present invention, when the optical design is made so that the parallel light beam incident on the condenser lens is condensed on the infrared sensor, for example, when the diameter of the condenser lens is 3 cm, the object to be measured is reached. Regardless of the distance, it is always possible to measure the temperature of the same area portion having a diameter of 3 cm on the surface of the object to be measured.

  The present invention guides the infrared light emitted from the non-measurement object to the infrared sensor and at the same time guides the visible light to the imaging camera without arranging a light splitter such as a prism between the condenser lens and the infrared sensor. In order to reduce the distance between the condenser lens and the infrared sensor by reducing the distance from the condenser lens to the infrared sensor, the infrared rays emitted from the surface of the object to be measured are collected. In a radiation thermometer that collects light on an infrared sensor by an optical lens and measures the temperature of the object to be measured by converting the amount of infrared light into a temperature, an imaging camera that images the object to be measured has an imaging optical axis on the object to be measured. It is embedded in the central portion of the condensing lens so as to coincide with the infrared measurement optical axis from the measurement object toward the condensing lens.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.
1 is an explanatory diagram showing a radiation thermometer according to the present invention, FIG. 2 is an explanatory diagram showing a viewing angle, FIG. 3 is an explanatory diagram showing a display, FIG. 4 is an explanatory diagram showing another embodiment according to the present invention, FIG. 5 is an explanatory diagram showing the viewing angle.

In the radiation thermometer 1 of this example, a condensing lens 4 comprising a convex lens for condensing infrared rays radiated from the surface of the object to be measured to an infrared sensor 3 such as a thermopile or a pyroelectric element is disposed on the front surface of the casing 2. The temperature of the object to be measured is measured by converting the amount of infrared rays of infrared rays reaching the infrared sensor 3 by the condensing lens 4 from the object to be measured along the measuring optical axis Z ₄ to the condenser lens 4. is doing.

Condenser lens 4 is formed on the annular perforated 4a in a central portion, in the hole 4a, the imaging camera 5 for imaging the object to be measured, towards the condenser lens 4 and imaging optical axis Z ₅ from the measurement object It is embedded to match the infrared measurement optical axis Z _4.
The imaging camera 5 includes an imaging lens 5 a and an imaging element 5 b, guides a light beam AL incident at a predetermined viewing angle to the imaging element 5 b, and an output signal is input to the image generation device 6. Then, the image data output from the image generation device 6 is input to the liquid crystal driver 7 and displayed on the liquid crystal display 8.

In this example, the viewing angle of the condenser lens 4 that collects infrared rays and the viewing angle of the imaging camera 5 are designed to be equal.
As a result, as shown in FIG. 2, as the distance to the object to be measured increases, the visual field range of the image Gn increases, and the radial difference (about 1 cm) between the condensing lens 4 and the imaging lens 5a from the image Gn. Infrared luminous flux IR radiated from a region Hn that is as large as about is incident on the condensing lens 4 and condensed on the light receiving surface 10 of the infrared sensor 3, so that the temperature measurement range always coincides with the image range.

The liquid crystal driver 7 is connected to a temperature measuring unit 9 that converts the temperature based on the amount of infrared light received by the infrared sensor 3, and temperature data output from the temperature measuring unit 9 is input to the liquid crystal driver 7.
The infrared sensor 3 has a large number of temperature sensing elements arranged on the light receiving surface 10, and the temperature measuring unit 9 outputs from the temperature sensing elements arranged around the area 10 b that is a shadow of the imaging camera 5. The temperature is measured based on the obtained data.

Further, the liquid crystal driver 7, the digital clock 11 for outputting date and time data D _C, the basic data display having an indicator display unit 12 for displaying the index MK indicating the position of the measurement light axis Z ₄ in a central position of the display 8 A device 13 is connected.
Thus, as shown in FIG. 3, it is possible to display the index MK, date data D _C and temperature data D _T on the liquid crystal display 8 for displaying an image captured by the imaging camera 5.

  In this example, when the main switch 14 is turned on, the imaging camera 5 is activated and its image is displayed on the liquid crystal display 8. When the temperature measurement button 15 is pressed, the temperature measurement unit 9 is activated and the temperature is displayed on the screen. Is displayed, and when the shutter button 16 is pressed, the temperature-displayed image is recorded in the memory 17.

The above is one configuration example of the present invention, and the operation thereof will be described next.
When the main switch 14 is turned on, the imaging camera 5 is activated and the image is displayed on the liquid crystal display 8. At this time, the indicator MK and date / time data are displayed on the display 8, but temperature data is not displayed.

  Next, while looking at the liquid crystal display 8, when the index MK displayed on the display 8 is matched with the measurement site of the object to be measured and the temperature measurement button 15 is pressed, the temperature measurement unit 9 is activated and the object to be measured is activated. Infrared rays incident from the surface according to the viewing angle of the condenser lens 4 are condensed on the infrared sensor 3 and the temperature is measured based on the amount of infrared rays, and temperature data is output from the temperature measurement unit 9 to the liquid crystal driver 7. The temperature is displayed on the liquid crystal display 8.

At this time, since the intersection point P position of the index MK matches the infrared measurement optical axis Z ₄ which is incident on the condenser lens 4, it is possible to accurately measure the temperature of the measurement site.
If the viewing angle of the condensing lens 4 that collects infrared rays and the viewing angle of the imaging camera 5 are designed to be equal, the temperature measurement range always matches the image range regardless of the imaging distance.

  If it is necessary to record the image with the temperature displayed on the liquid crystal display 8, the image indicating the measurement date and time and the temperature is recorded in the memory 17 by pressing the shutter button 16.

FIG. 4 shows another embodiment of a radiation thermometer according to the present invention, and the same parts as those in FIG.
As shown in FIG. 4, the radiation thermometer 21 of this example uses a condenser lens 4 and an infrared sensor 3 so that an infrared parallel light beam PL incident on the lens 4 is condensed on the light receiving surface 10 of the infrared sensor 3. Example 1 is the same as Example 1 except for optical design.
That is, as shown in FIG. 5, as the distance to the object to be measured increases, the field of view of the image Gn increases, but the parallel light beam PL incident on the condenser lens 4 is collected on the light receiving surface 10 of the infrared sensor 3. Because it is illuminated, the temperature measurement range can always be kept constant.

In addition, if the figure which displayed the diameter line orthogonal, for example in a circle is displayed on the liquid crystal display 8 as the parameter | index MK by the parameter | index display means 12 with which the liquid crystal driver 7 was equipped, the intersection P of the diameter line will always be measured. Since it coincides with the optical axis Z ₄ , it is very easy to make the intersection P coincide with the part to be measured, and there are few occurrences of measurement errors due to mismatch between the measurement optical axis Z ₄ and the measurement part.
Since the parallel light beam incident on the condenser lens 4 is optically designed to be condensed on the infrared sensor 3, for example, when the aperture of the condenser lens is 3 cm, the distance to the object to be measured is set. Regardless, the temperature of the same area portion having a diameter of 3 cm on the surface of the object to be measured can always be measured.

As described above, in any of the embodiments, since the imaging camera 5 is embedded in the infrared condenser lens 4, it is necessary to arrange an optical branching device such as a prism between the condenser lens 4 and the infrared sensor 3. Since the distance between them can be shortened, the radiation thermometer can be miniaturized.
In the above-described embodiment, the case where the optical design is made so that the viewing angle of the infrared light incident on the condenser lens 4 is equal to the viewing angle of the imaging camera 5, and the infrared light incident in parallel to the condenser lens 4 is infrared. Although the case where the optical design is made so that the light is condensed on the sensor 3 has been described, the present invention is not limited to this, and if the measurement area need not be so clear, the condensing lens 4 and the imaging camera 5 have different fields of view. You may design so that it may enter with an angle | corner.
Moreover, as an infrared sensor, arbitrary infrared sensors, such as a thermopile and a pyroelectric element, can be used.

  The present invention can be applied to the use of a radiation thermometer that measures the temperature of an object by measuring the amount of infrared rays radiated from the surface of the object to be measured in a non-contact manner and converting the temperature.

Explanatory drawing which shows the radiation thermometer which concerns on this invention. Explanatory drawing which shows the relationship of a viewing angle. Explanatory drawing which shows a liquid crystal display. Explanatory drawing which shows the other radiation thermometer which concerns on this invention. Explanatory drawing which shows the relationship of a viewing angle. Explanatory drawing which shows a conventional apparatus.

Explanation of symbols

1 21 Radiation thermometer 3 Infrared sensor 4 Condensing lens Z ₄ Measurement optical axis 5 Imaging camera Z ₅ Imaging optical axis 8 Liquid crystal display MK Index 12 Index display means

Claims (5)

In the radiation thermometer that measures the temperature of the object to be measured by condensing the infrared ray radiated from the surface of the object to be measured on the infrared sensor by the condensing lens, and converting the amount of the infrared rays into the temperature.
An imaging camera for imaging the object to be measured is embedded in the central portion of the condenser lens so that its imaging optical axis coincides with the infrared measurement optical axis from the object to be measured to the condenser lens. A radiation thermometer.   2. A radiation thermometer according to claim 1, wherein a plurality of temperature sensing elements are arranged on the light receiving surface of the infrared sensor, and the temperature is measured by a temperature sensing element arranged around a shadowed portion of the imaging camera. .   The radiation thermometer according to claim 1, further comprising a display that displays an image of the imaging camera, and an index display unit that displays an index indicating the position of the measurement optical axis on the display.   The radiation thermometer according to any one of claims 1 to 3, wherein the radiation thermometer is optically designed so that a viewing angle of an infrared beam incident on the condenser lens is equal to a viewing angle of an imaging camera. The radiation thermometer according to any one of claims 1 to 3, wherein the condensing lens and the infrared sensor are optically designed so that a parallel light beam incident on the lens is condensed on the infrared sensor.

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