JP2003227752A - Infrared noncontact temperature sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a correct control signal by removing a contaminant adhering to the surface of a window plate constituting an entrance window and by correcting an output by a prescribed means even when the contaminant adheres. <P>SOLUTION: An infrared noncontact temperature sensor 10 is provided so as to be equipped with a cleaning device 6 used to remove the contaminant on the surface of the window plate 1 constituting the entrance window 3 on which infrared rays L are incident. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
Alternatively, the present invention relates to an infrared non-contact type temperature sensor capable of measuring the temperature of a defective object when it comes into contact with the object in a non-contact state.

[0002]

2. Description of the Related Art Infrared non-contact temperature sensors capable of measuring the temperature of an object in a non-contact state have been conventionally used in various fields.

[0003]

An object whose temperature is to be measured by an output signal (hereinafter referred to as a temperature measuring object)
When controlling the temperature of the infrared non-contact temperature sensor, substances contained in the atmosphere in which the infrared non-contact temperature sensor is installed must adhere to the surface of the window plate that constitutes the entrance window of the infrared non-contact temperature sensor. There is a
There is a risk that the energy of infrared rays reaching the detection element will become small and an incorrect control signal will be generated, causing the temperature of the temperature measuring object to deviate from the normal range, affecting not only the quality but also causing a serious accident. Sex has occurred.

Therefore, in the present invention, the contaminants adhering to the surface of the window plate constituting the incident window of the infrared non-contact temperature sensor are removed or the output is corrected by a predetermined means even if the contaminants are adhered. Or by
Provided is an infrared non-contact temperature sensor which can obtain a correct control signal.

[0005]

The invention according to claim 1 provides an infrared type non-contact temperature sensor having a cleaning device for removing surface contaminants of a window plate constituting an entrance window.

In the invention according to claim 2, an area (hereinafter referred to as a reference area) where surface contaminants do not adhere is provided by covering a part of the window plate constituting the entrance window with an openable / closable cover, The output of the infrared non-contact temperature sensor is calibrated by opening and closing the cover.

According to a third aspect of the present invention, an infrared ray is provided with a cleaning device for removing surface contaminants on a portion of the window plate constituting the incident window other than the reference area (hereinafter referred to as a measurement area). A non-contact type temperature sensor is provided.

According to a fourth aspect of the present invention, there is provided an infrared non-contact temperature sensor having a cleaning device for removing surface contaminants of the reference area of the window plate constituting the incident window.

In the invention according to claim 5, by covering a part of the window plate having an area larger than the effective area of the incident window with a cover, the effective area of the incident window or a reference area having a larger area and the incident window. Infrared non-contact type temperature which is provided with a measurement area having an effective area or a larger area, and the window plate can be moved so that the entrance window can be covered with the measurement area or the reference area. Provide a sensor.

According to a sixth aspect of the present invention, the infrared non-contact type temperature is adapted to remove contaminants on the surface of the measurement area of the window plate which constitutes the incident window by utilizing the movement of the window plate. Provide a sensor.

According to a seventh aspect of the present invention, the entrance window has an effective area or a wider area than that of the entrance window.
Of the two windows having the same thickness, one of them is covered with a cover, and an uncovered window (hereinafter referred to as measurement window) and a covered window (hereinafter referred to as reference window) Provided is an infrared non-contact temperature sensor capable of simultaneously moving the reference window plate and the measurement window plate so that the entrance window can be covered with the measurement window plate or the reference window plate.

According to an eighth aspect of the present invention, there is provided an infrared non-contact temperature sensor, which utilizes the movement of the window plate to remove surface contaminants of the measurement window plate that constitutes the incident window. provide.

In the invention according to claim 9, the opposite end faces of the window plate constituting the entrance window are slanted and polished.
Of the two windows that have the same shape and size, one of them is covered with a cover to serve as a reference window board, and the other window board is provided as a measurement window board to detect infrared light sources and reference window boards. Provide an infrared non-contact temperature sensor that makes an infrared ray emitted from an infrared light source pass through the window plate while repeating total reflection by configuring an optical system with a detector, a detector for the measurement window plate, and a reflecting mirror. To do.

According to a tenth aspect of the present invention, there is provided an infrared type non-contact temperature sensor having a cleaning device for removing surface contaminants of the measurement window plate.

According to the first aspect of the present invention, according to the infrared non-contact type temperature sensor described above, the window plate constituting the incident window is always kept clean, and the temperature of the temperature measuring object is accurately measured. be able to.

According to the second aspect of the present invention, the output of the infrared non-contact temperature sensor can be corrected, and the influence of contaminants on the surface of the window plate constituting the entrance window can be reduced.

According to the invention of claim 3, since the output of the infrared non-contact temperature sensor can be corrected, the number of times of cleaning the window plate constituting the entrance window can be reduced.

According to the fourth aspect of the present invention, the reference area that has a chance to come into contact with the atmosphere in which the infrared non-contact temperature sensor is installed can be kept clean, so that the output of the infrared non-contact temperature sensor can be corrected. The reliability is improved.

According to the fifth aspect of the present invention, the area of the entrance window can be effectively used during measurement while having the function of correcting the output of the infrared non-contact type temperature sensor, and therefore the sensitivity is lowered. It becomes possible to measure without.

According to the sixth aspect of the present invention, by providing a cleaning device for removing the surface contaminants in the measurement area by using the movement of the window plate, the contaminants on the surface of the measurement area are obtained every time the reference output is obtained. Is eliminated, and it becomes possible to further extend the stable operation time of the infrared non-contact temperature sensor.

According to the invention of claim 7, by dividing the window plate covering the incident window into the reference window plate and the measurement window plate, the measurement window plate is contaminated and the infrared non-contact type temperature sensor. When the function that can correct the output becomes insufficient, only the measurement window plate can be replaced and the reference window plate can be continuously used, so that the running cost can be suppressed.

According to the invention of claim 8, by providing a cleaning device for removing surface contaminants of the measurement window plate by utilizing the movement of the window plate, the measurement window plate surface is obtained every time the reference output is obtained. Since the pollutants are removed, it is possible to further extend the stable operation time of the infrared non-contact temperature sensor, and the measurement window plate is contaminated due to long-term use, and it becomes impossible to recover. In this case, only the measurement window plate can be replaced and the reference window plate can be used continuously, so that the running cost can be suppressed.

According to the invention of claim 9, in addition to the surface on which the infrared rays radiated from the surface of the temperature-measuring object enter the reference window plate and the measurement window plate forming the entrance window, the infrared rays prepared separately The infrared radiation emitted from the light source is provided with a surface and the surface from which the infrared radiation is emitted, and the infrared radiation emitted from the infrared light source passes through the reference window plate and the measurement window plate while repeating total reflection, and the reference window plate By arriving at the detector and the detector for the measurement window plate, it is possible to obtain a signal for correcting the output of the infrared non-contact temperature sensor at the same time while measuring the temperature of the surface of the temperature measuring object. In addition to the above, the reference window plate has no chance of touching the atmosphere in which the infrared non-contact temperature sensor is installed and can be kept clean at all times, so the reliability and stability of the infrared non-contact temperature sensor It can be increased.

According to the tenth aspect of the present invention, by providing the cleaning device for removing the surface contaminants of the measurement window plate, the time period during which the infrared non-contact temperature sensor operates stably is dramatically lengthened. It will be possible.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the infrared type non-contact temperature sensor of the present invention will be described with reference to specific examples. The infrared non-contact temperature sensor of the present invention,
The present invention is not limited to the example shown below.

[Embodiment 1] FIG. 1 is a side view showing a schematic configuration of an example of an infrared non-contact temperature sensor 10 of the present invention. The infrared non-contact type temperature sensor 10 includes an incident window 2 on which an infrared ray L radiated from the surface of a temperature measuring object is incident, and a condenser mirror 3 which condenses the infrared ray L from the incident window 2.
And a detection element 4 for detecting the collected infrared rays L, and an electronic circuit 5 for converting the infrared rays detected by the detection element 4 into a signal and outputting the signal.

In this infrared non-contact temperature sensor 10, as shown in FIG. 1, the infrared rays L radiated from the surface of the temperature measuring object enter through the window plate 1 attached to the entrance window 2 and the condenser mirror. It is condensed by 3 and reaches the detection element 4. The infrared ray L detected by the detection element 4 is
The temperature of the surface of the temperature-measuring object is measured in a non-contact manner based on the calibration curve of the output which is converted into a signal by the electronic circuit 5 and is taken out from the temperature of the surface of the temperature-measuring object, and a control signal is generated.

An infrared transparent material is used as the material of the window plate 1. Specifically, thallium bromide iodide (KRS-
5), thallium bromide chloride (KRS-6), germanium (Ge), silicon (Si), zinc sulfide (ZnS), zinc selenide (ZnSe), silver chloride (AgCl), silver bromide (AgBr), etc. Can be applied. The materials described above can be applied to the window plate in each of the following embodiments.

Infrared non-contact temperature sensor 1 described above
When 0 is used for a long time, the substance contained in the atmosphere in which the infrared non-contact temperature sensor 10 is installed adheres to the window plate 1 and the energy of the infrared light L reaching the detection element 4 becomes small. As a result, an erroneous control signal is generated, causing the temperature of the temperature-measuring object to deviate from the normal range.

Infrared non-contact temperature sensor 1 of the present invention
In 0, in order to solve the above problems,
The cleaning device 6 was provided on the infrared L incident surface side at a position facing the surface of the window plate 1. The cleaning device 6 can appropriately remove the substance adhering to the surface of the window plate 1, and the substance temperature can be accurately measured. As the cleaning device 6, a conventionally known window plate 1 such as a pad, a brush, or a blade is used.
Any material can be applied as long as it has a function of cleaning the surface of.

[Embodiment 2] FIGS. 2A and 2B are schematic side views showing another example of the infrared non-contact temperature sensor 10. In this example, a part of the window plate 1 is covered with a cover 7 that can be opened and closed on the surface of a predetermined region on the incident surface side of the infrared rays L of the window plate 1, and the region covered by the cover 7 is a reference area. The configuration is provided as 70. Cover 7 is infrared L
Shall be formed of a material that does not pass through. As shown in FIG. 2 (b), the cover 7 is supposed to be openable / closable as required, and the infrared non-contact temperature sensor 10 of the infrared type non-contact type temperature sensor 10 when the cover 7 is closed and when the cover 7 is open. If the outputs are Ic and Io, respectively, the window plate 1
When the measurement area 80 (area not covered by the cover 7) is clean, the following formula [Equation 1] is established.

[0032]

[Formula 1] Ic / Io = kSM / (SR + SM)

SR, SM and k in the above [Formula 1] are defined below. SR: area of reference area 70 SM: area of measurement area 80 k: constant

As described above, when the measurement area 80 is contaminated by the substance contained in the atmosphere in which the infrared type non-contact temperature sensor 10 is installed, Ic / Io
Becomes smaller. Accurate temperature measurement is possible by correcting the output so that an erroneous control signal is not generated according to the value obtained from this equation.

[Embodiment 3] The cleaning device 6 described in [Embodiment 1] shown in FIG. 1 is provided in the measurement area 80 described in [Embodiment 2]. This makes it possible to perform stable temperature measurement even when the infrared non-contact temperature sensor 10 is operated for a long time.

[Embodiment 4] The reference area 70 described in [Embodiment 2] also touches the atmosphere in which the infrared non-contact temperature sensor 10 is installed for a short time. The cleaning device 6 described with reference to FIG. 1 in [Embodiment 1] is provided. This makes it possible to perform stable temperature measurement even when the infrared non-contact temperature sensor 10 is operated for a long time.

[Embodiment 5] In FIGS. 3 (a) and 3 (b),
The schematic plan view of the state of the other example of the infrared non-contact temperature sensor 10 as seen from the upper surface is shown. Figure 3 (a) shows the measurement
FIG. 3B shows a position state of the window plate 1 at the time of reference.
In this example, one window plate 1 has a measurement area 80 having an area covering the effective area of the entrance window 2 and an area normally covered by the cover 7 and covering the effective area of the entrance window 2. The reference area 70 is provided, and the window plate 1 is moved as necessary to cover the entrance window 2 with the reference area 70 so that a reference output for correcting the output can be obtained.

[Embodiment 6] FIGS. 4 (a) and 4 (b)
The schematic plan view of the state of the other example of the infrared non-contact temperature sensor 10 as seen from the upper surface is shown. Figure 4 (a) shows the measurement
FIG. 4B shows a position state of the window plate 1 at the time of reference.
The infrared non-contact temperature sensor 10 in this example is
It is assumed that the infrared type non-contact temperature sensor 10 shown in FIGS. 3 (a) and 3 (b) of [Fifth Embodiment] is provided with a cleaning device 6. During the measurement shown in FIG. 4A, the cleaning device 6 is kept away from the window plate 1, and from the reference time shown in FIG.
Immediately before returning to the measurement of (a), the cleaning device 6 is brought into contact with the window plate 1 so that the movement of the window plate 1 causes the cleaning device 6 to rub the window plate 1 to remove contaminants on the surface of the measurement area. did.

[Embodiment 7] FIGS. 5 (a) and 5 (b)
The schematic plan view of the state of the other example of the infrared non-contact temperature sensor 10 as seen from the upper surface is shown. Fig. 5 (a) shows the measurement
FIG. 5B shows a position state of the window plate 1 at the time of reference.
The infrared non-contact temperature sensor 10 in this example is
Two window plates having the same material and thickness and having an area capable of covering the effective area of the entrance window 2 are prepared, and a reference window plate 1b covered with a cover 7 and an uncovered measurement window plate 1a are provided, If necessary, the reference window plate 1b and the measurement window plate 1a are simultaneously moved to cover the entrance window 2 with the reference window plate 1b so that a standard output for correcting the output can be obtained.

[Embodiment 8] FIGS. 6 (a) and 6 (b) show that
The schematic plan view of the state of the other example of the infrared non-contact temperature sensor 10 as seen from the upper surface is shown. Fig. 6 (a) shows the measurement
FIG. 6B shows a position state of the window plate 1 at the time of reference.
The infrared non-contact temperature sensor 10 in this example is
It is assumed that the infrared type non-contact temperature sensor 10 shown in FIGS. 5 (a) and 5 (b) of the above [Embodiment 7] is provided with a cleaning device 6. At the time of the measurement shown in FIG. 6 (a), the cleaning device 6 is kept away from the measurement window plate 1a, and cleaning is performed immediately before returning from the reference time shown in FIG. 6 (b) to the measurement time shown in FIG. 6 (a). The device 6 is brought into contact with the measurement window plate 1a, and the measurement window plate 1a
The cleaning device 6 rubs the measurement window plate 1a to remove contaminants on the surface of the measurement area.

[Embodiment 9] FIGS. 7 to 9 are schematic structural views of another example of the infrared non-contact temperature sensor 10.
FIG. 7 shows a schematic side view of the infrared type non-contact temperature sensor 10, and FIGS. 8 and 9 show a schematic configuration diagram of a normal state of a main part of the infrared type non-contact temperature sensor seen from above. In these examples, the reference window plate 1b and the measurement window plate 1a forming the entrance window 2 are provided with a separately prepared infrared light source 8 in addition to the surface on which the infrared rays L emitted from the surface of the temperature measuring object are incident. A surface on which the emitted infrared ray is incident and a surface on which the infrared ray is emitted are provided, and the infrared ray emitted from the infrared light source 8 passes through the reference window plate 1b and the measurement window plate 1a while repeating total reflection. By arriving at the reference window detector 12 and the measurement window detector 11, respectively, the output of the infrared non-contact temperature sensor is measured at the same time while measuring the temperature of the surface of the temperature-measuring object. This makes it possible to obtain a signal for correction. Further, according to such a configuration, the reference window plate 1b does not have a chance to come into contact with the atmosphere in which the infrared non-contact temperature sensor is installed and can be kept clean at all times. It has a function of increasing stability.

As shown in FIG. 7, the opposite end faces of the window plate 1 constituting the entrance window 2 are polished with a predetermined inclination.
Two window plates having the same material, shape, and size are prepared, and a reference window plate 1b covered with a cover 7 and an uncovered measurement window plate 1a are provided. When the reference window plate 1b is covered with the cover 7, the cover 7 should not touch the surface of the reference window plate 1b corresponding to the surface through which the infrared rays L emitted from the surface of the temperature-measuring object pass through the measurement window plate 1a. There is a need to.

As shown in FIGS. 8 and 9, the infrared rays L emitted from the infrared light source 8 are the reference window plate 1b and the measurement window plate 1.
It is incident from one side of the end surface of a which is obliquely polished, and travels through the reference window plate 1b and the measurement window plate 1a while repeating total reflection, and the reference window plate 1b and the measurement window plate 1a are obliquely polished. The reference window plate detector 12 and the measurement window plate detector 11 reach from the other of the end faces.

FIG. 8 is a top view showing the arrangement of the infrared light source 8, the reflecting mirror 9, the cover 7, the reference window plate 1b (inside the cover 7) and the reference window plate detector 12. The outputs of the reference window detector 12 and the measurement window detector 11 are
If I _R and I _M , respectively, in the case where the reference window plate 1b is clean, I _M / I _R = 1 in principle, but the surface of the measurement window plate 1a is an infrared non-contact temperature sensor. When contaminated with substances contained in the installed atmosphere, I _M / I
_R <1. This is based on a method and principle called a total reflection absorption spectrum method (ATR method) or a multiple reflection absorption spectrum method (MIR method) in the field of infrared spectroscopy. The output of the non-contact temperature sensor was corrected based on the value of I _M / I _{R so} that an erroneous control signal was not generated.

Although the reference window plate 1b is arranged on the measurement window plate 1a in FIG. 7, it is also possible to dispose the reference window plate 1b and the both on the same plane as shown in FIG.

[Embodiment 10] FIG. 10 shows a schematic side view of another example of the infrared non-contact type temperature sensor 10. In this embodiment, FIGS. The infrared ray non-contact type temperature sensor 10 shown in the drawing has a measurement window plate 1a provided with a cleaning device 6. With such a configuration, contaminants on the surface of the measurement area can be removed, and stable temperature measurement can be performed even when the infrared non-contact temperature sensor is operated for a long time. .

[0047]

INDUSTRIAL APPLICABILITY The infrared non-contact temperature sensor of the present invention is applied to an image forming apparatus such as a copying machine or a printer to measure the temperature of a roller for fixing toner without contacting the roller. Therefore, it is possible to prevent the image quality from being deteriorated due to a scratch on the surface of the fixing roller as in the case of the method of measuring the temperature by contacting with a roller such as a thermistor.

The infrared non-contact type temperature sensor of the present invention can be applied to the temperature measurement of an object such as food which cannot be contacted in an apparatus for heating food such as a microwave oven.

The infrared non-contact type temperature sensor of the present invention can be applied to temperature measurement in a place where large equipment such as a blast furnace is inaccessible.

According to the infrared non-contact type temperature sensor of the first aspect, the window plate constituting the entrance window is always kept clean, and the temperature of the temperature measuring object can be accurately measured.

According to the infrared non-contact type temperature sensor of the second aspect, the output of the infrared non-contact type temperature sensor can be corrected, and the influence of contaminants on the surface of the window plate constituting the entrance window can be prevented. Could be reduced.

According to the infrared type non-contact type temperature sensor of the third aspect, the output of the infrared type non-contact type temperature sensor can be corrected, so that the number of times of cleaning the window plate constituting the entrance window is reduced. It was planned.

According to the infrared non-contact type temperature sensor of the fourth aspect, the reference area which has a chance to touch the atmosphere in which the infrared non-contact type temperature sensor is installed can be kept clean. The reliability of output correction of the temperature sensor was improved.

According to the infrared non-contact temperature sensor of the fifth aspect, the area of the entrance window can be effectively used during measurement while having the function of correcting the output of the infrared non-contact temperature sensor. Therefore, it is possible to perform the measurement without lowering the sensitivity.

According to the infrared non-contact type temperature sensor according to the sixth aspect, by providing the cleaning device for removing the surface contaminants in the measurement area by using the movement of the window plate, every time the reference output is obtained. The contaminants on the surface of the measurement area were removed, and it became possible to further extend the stable operation time of the infrared non-contact temperature sensor.

According to the infrared non-contact temperature sensor of the seventh aspect, by dividing the window plate covering the incident window into the reference window plate and the measurement window plate, the measurement window plate is contaminated and the infrared type is used. When the function of correcting the output of the non-contact type temperature sensor is insufficient, only the measurement window plate can be replaced and the reference window plate can be continuously used, so that the running cost can be suppressed.

According to the infrared non-contact type temperature sensor according to the eighth aspect, by providing the cleaning device for removing the surface contaminants of the measurement window plate by utilizing the movement of the window plate, it is possible to obtain the reference output. Since the pollutants on the surface of the measuring window plate are removed, the time when the infrared non-contact type temperature sensor operates stably can be further extended, and the measuring window plate is contaminated by long-term use, When it becomes impossible to recover, only the measurement window plate can be replaced and the reference window plate can be used continuously, so the running cost was suppressed.

According to the infrared non-contact type temperature sensor of the ninth aspect, the reference window plate and the measurement window plate forming the incident window are provided with other surfaces on which infrared rays emitted from the surface of the temperature measuring object are incident. In addition, there is a surface on which the infrared light emitted from the infrared light source prepared separately and a surface from which the infrared light is emitted are provided, and while the infrared light emitted from the infrared light source repeats total reflection, the inside of the reference window plate and the measurement window plate By passing through and reaching the detector for the reference window plate and the detector for the measurement window plate respectively, it is possible to correct the output of the infrared non-contact temperature sensor while measuring the temperature of the surface of the temperature measuring object. In addition to being able to obtain a signal, there is no opportunity for the reference window plate to come into contact with the atmosphere in which the infrared non-contact temperature sensor is installed, and it is possible to keep it clean at all times. Reliability of Nsa, was able to increase the stability.

According to the infrared non-contact type temperature sensor of the tenth aspect, by providing a cleaning device for removing the surface contaminants of the measurement window plate, the time required for the infrared non-contact type temperature sensor to operate stably. It has become possible to dramatically increase the length.

[Brief description of drawings]

FIG. 1 shows a schematic side view of an infrared non-contact temperature sensor of the present invention.

FIG. 2 (a) is a schematic side view showing a state of another example of the infrared non-contact temperature sensor of the present invention. (B) A schematic side view in a state of another example of the infrared non-contact temperature sensor of the present invention is shown.

FIG. 3 (a) is a schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention. (B) A schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention is shown.

FIG. 4 (a) is a schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention. (B) A schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention is shown.

FIG. 5A is a schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention. (B) A schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention is shown.

FIG. 6 (a) is a schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention. (B) A schematic plan view seen from the upper surface in a state of another example of the infrared non-contact temperature sensor of the present invention is shown.

FIG. 7 shows a schematic side view of another example of the infrared non-contact temperature sensor of the present invention.

FIG. 8 is a schematic view of a main part of another example of the infrared non-contact temperature sensor of the present invention.

FIG. 9 is a schematic view of a main part of another example of the infrared non-contact temperature sensor of the present invention.

FIG. 10 shows a schematic side view of another example of the infrared non-contact temperature sensor of the present invention.

[Explanation of symbols]

1 window board 1a Window plate for measurement 1b Reference window plate 2 incident window 3 Focusing mirror 4 sensing elements 5 electronic circuits 6 cleaning device 7 cover 8 infrared light source 9 Reflector 10 Infrared non-contact temperature sensor 11 Detectors for measurement window plates 12 Detector for reference window plate 70 reference areas 80 measurement areas

Claims (10)

[Claims] 1. An infrared non-contact type temperature sensor, comprising: a cleaning device for removing surface contaminants of a window plate constituting an incident window for entering infrared rays. Mold temperature sensor. 2. An area (hereinafter referred to as a reference area) to which surface contaminants are not attached is provided by covering at least a part of the window plate constituting the entrance window with an openable / closable cover, and the cover is opened / closed. The infrared type non-contact temperature sensor is characterized in that the output of the infrared type non-contact temperature sensor is calibrated. 3. A cleaning device for removing surface contaminants on a portion of the window plate constituting the entrance window other than the reference area (hereinafter referred to as a measurement area). Infrared non-contact temperature sensor described in. 4. The infrared non-contact temperature sensor according to claim 3, further comprising a cleaning device for removing surface contaminants of the reference area of the window plate forming the incident window. 5. An infrared non-contact type temperature sensor, wherein a part of a window plate having an area larger than an effective area of an incident window on which infrared rays are incident is covered with a cover so as to have an effective area of the incident window or wider. An area reference area and an effective area of the entrance window or a measurement area having a larger area, and the window can be moved so that the entrance window can be covered with the measurement area or the reference area. Infrared non-contact temperature sensor. 6. The infrared non-contact type according to claim 5, wherein the movement of the window plate is used to remove contaminants on the surface of the measurement area of the window plate forming the incident window. Temperature sensor. 7. An infrared non-contact type temperature sensor, wherein one of two window plates having the same effective material area or a larger area than the effective area of an incident window for incident infrared light. The plate is covered with a cover, an uncovered window plate (hereinafter, referred to as measurement window plate) and a covered window plate (hereinafter, referred to as reference window plate) are provided, and the entrance window is replaced by the measurement window plate or the measurement window plate. An infrared non-contact temperature sensor, wherein the reference window plate and the measurement window plate can be simultaneously moved so as to be covered with the reference window plate. 8. The infrared non-contact temperature sensor according to claim 7, wherein the movement of the window plate is used to remove surface contaminants of the measurement window plate that constitutes the incident window. . 9. An infrared non-contact temperature sensor, wherein two window plates having the same material, shape, and size, in which the opposite end faces of the window plate constituting the incident window are obliquely polished,
One window plate is covered with a cover to serve as a reference window plate, the other window plate is provided as a measurement window plate, and an infrared light source, a reference window plate detector, a measurement window plate detector, and a reflector are used. An infrared non-contact temperature sensor, which constitutes an optical system, in which infrared light emitted from an infrared light source passes through the window plate while repeating total internal reflection. 10. The infrared non-contact temperature sensor according to claim 9, further comprising a cleaning device for removing surface contaminants of the measurement window plate.