JPS62106327A - Radiation thermometer - Google Patents

Abstract

PURPOSE:To make it possible to measure temp. with high accuracy even if a measuring object moves, by providing a transmission area having an area larger than the image of the measuring object to an image forming optical system and arranging a condensing lens between the transmission area and a detector. CONSTITUTION:A field stop 12 is arranged on the image forming surface of a measuring object and a window (transmission area) 12a having a shape similar to that of a measuring area is formed to said stop 12 in such a state that the image of the measuring object held to a stationary state is placed at the center. Because the field stop 12 is considerably larger than a detector 14, by placing a condensing lens 13 between the field stop 12 and the detector 14, the radiation passed through the field stop 12 can be entirely condensed to the detector 14. Therefore, even if the measuring object slightly moves, the measuring object can be always received in the detector 14. Because an image is formed on the detector 14 in such a state that the image of the window 12a is contracted by the lens 13, the detector 14 can be miniaturized.

Description

[Detailed Description of the Invention] The present invention uses an object that moves within a certain range as a measurement object, and determines the measurement object based on the radiant energy emitted from the object (measurement object). This invention relates to a radiation thermometer that measures the temperature of.

A conventional radiation thermometer includes an imaging optical system that has an aperture (diaphragm) that limits the flux of radiant energy, and an imaging optical system that is formed on the imaging surface of this imaging optical system to perform measurements at the position of the measurement target. There are radiation thermometers that are equipped with a transmission region (for example, a window formed in a field stop) for determining the area and a detector of a radiation measuring means placed behind this transmission region (for example, (See Publication No. 60-027825).

If a measurement area with a size equal to the measurement target is set, the measurement target may move and go outside the measurement area. In such a case, the radiant energy from the object to be measured will be lower than the predetermined radiant energy, making it impossible to accurately measure the temperature of the object to be measured.

Therefore, by making the measurement area larger than the measurement target, the measurement target can be easily placed within the measurement area, and even if the measurement target moves slightly, the measurement target can always be kept within the measurement area. It can be done.

For example, in the case of a radiation thermometer that measures the temperature of a power transmission line as a factor in regulating transmitted power, the measurement area of the radiant energy measuring means should be approximately three times the diameter of the transmission line. By doing so, even if the power lines are swayed by the wind, the power lines can be kept within the measurement area at all times.

As mentioned above, in order to make the measurement area larger than the measurement target, it is necessary to increase the transmission range for determining the measurement area at the position of the measurement target. In order to capture all of the radiant energy that has passed through such a large transmission area, a detector with a correspondingly large area is required.

However, it is very difficult to obtain and manufacture such large area detectors.

Furthermore, it is common for detectors to have uneven sensitivity depending on their location. The larger the area, the more severe the sensitivity unevenness. Therefore, if the object to be measured moves and the projection position of its image on the detector changes, an error will occur in the measured temperature of the object due to the above-described uneven sensitivity.

The present invention was made in view of these circumstances, and aims to enable the use of a small-area detector and to improve the accuracy of temperature measurement despite the movement of the measurement target. shall be.

The present invention for calculating p-divination has the following configuration in order to solve the above-mentioned problems.

That is, the radiation thermometer of the present invention includes an imaging optical system having an aperture that limits the luminous flux of radiant energy, and an imaging optical system formed on an imaging surface of the imaging optical system. a transmission region having an area larger than the image of the measurement target; a detector of the radiant energy measuring means arranged behind the transmission region; and a reduction of the aperture arranged between the transmission region and the detector; and a condenser lens that forms an image on the detector.

standing-buttocks The effects of this configuration are as follows.

Since the area of the transmission region is larger than the image of the measurement object formed on the imaging plane of the imaging optical system, the measurement area at the position of the measurement object becomes larger than the measurement object due to the transmission region.

Therefore, the object to be measured can be easily placed within the measurement area, and even if the object to be measured moves slightly, the object to be measured can always be kept within the measurement area.

That is, even if the object to be measured moves, the radiant energy from the object to be measured that enters the detector remains constant.

On the other hand, the area of the transmission region is configured to be larger than the image of the measurement target formed on the imaging plane, and a condenser lens is placed between the transmission region and the detector. Since the condenser lens is configured to form a reduced image of the aperture on the temperature sensor, it is necessary for the detector to capture all of the radiant energy that has passed through the aperture. need not have such a large area.

Therefore, the radiation thermometer can be manufactured easily and is advantageous in terms of cost.

In addition, as mentioned above, it is normal for a detector to have uneven sensitivity depending on its part, and the larger the area, the more severe the uneven sensitivity is. All of the energy is captured by a detector,
Even if the object to be measured moves and the projection position of its image on the transmission area changes, a reduced image of the aperture is always projected on the detector, so there will be no error in the measured temperature even if the object to be measured moves. .

■Measurement Situation> First, the situation of temperature measurement using a radiation thermometer will be explained based on FIGS. 1 and 2.

Figure 1 is a schematic front view showing the installation status of the radiation thermometer;
FIG. 2 is an explanatory diagram of the measurement situation.

In Figure 1, (1) is a high-voltage steel tower, (2) is an insulator (
3) a power transmission line supported on the high voltage tower (1) via (A
) is a radiation thermometer installed on the high-voltage tower (1) directly above the power transmission &I (2>).

As shown in FIG. 2, the radiation thermometer (A) has a first radiometer (RDI) and a second radiometer (RDz). (4
) is a bidirectional optical link connected to the radiation temperature needle (A), (5) is E connected to the radiation thermometer (A)
It is a t source. As this power source (5), it is preferable to use a solar cell in order to insulate the radiation thermometer (A) from the power transmission line (2) of the power source (2).

The first radiometer (RDI') captures radiant energy (infrared rays) from the power transmission line (2), which is the object of temperature measurement. The second radiation needle (RDz) captures radiant energy (infrared rays) from the bank ground (ground).

The diameter of the power transmission line (2) is usually about 10 to 40 m. Assume that the power transmission line (2) swings from side to side with an amplitude approximately twice the diameter of the line. Since the first radiometer (RD,) needs to capture the thermal radiation from the power transmission &a (2) that fluctuates in this way, it is shown in Figure 3 as the measurement area in the horizontal plane passing through the heart of the power transmission &a (2). The first measurement area (A,) as shown is set.

This first measurement area (A1) has a rectangular shape with dimensions aXb. The short side a is the maximum wire diameter of the power transmission line (2) (approximately 4
0 m), and the long side is about three times the wire diameter.

From the first measurement area (A,), not only the radiant energy from the power transmission line (2) but also the radiant energy from the background passes through and is captured by the first radiometer (RDI).

The radiant energy captured in this way includes radiant energy from the background, so it is
2) In order to measure the radiant energy itself, it is necessary to remove the radiant energy from the bank ground. Therefore, a second radiometer (RDg) is provided to capture only the radiant energy from the background.

The measurement area for this second radiometer (RD) is the power transmission line (
2), in the horizontal plane passing through the center of the first measurement area (A,
) is set at an interval β from the first measurement area (A1) without overlapping with the second measurement area CAt). This distance l is also the distance between the optical axis of the first radiometer (RDI) and the optical axis of the second radiometer (RDI). This second measurement area (A2) is circular with a radius C.

Measuring method: If the first measurement area (A,) is set with the center of the power line (2) as the axis of symmetry, the power line (2) will sway with an amplitude approximately twice the wire diameter. However, the first measurement area (A,
), and the power transmission line (2) is located within
There is no power transmission &i (2) in the measurement area (A2).

Power transmission at temperature TL: %I The radiant energy per unit area radiated from (2) is E(TL), the emissivity of the power transmission line (2) is 64, and the radiant energy per unit area from the bank ground is E −.

The total radiant energy E captured by the first radiometer (RDI) from the first measurement area (A1) is
Assuming that the constant determined by the characteristics of the optical system is 1, Et = ni+ ・a
(b-D) ・Em) = K+ It is r/b.

Since r=D/b=D ・a/b−a, this “is,
Power transmission i (2
) is the ratio of the areas of Therefore, hereinafter, it will be referred to as area ratio r.

The total radiant energy E2 captured by the second radiometer (RD) from the second measurement area (A,) is expressed as Et''k, where the constant determined by the characteristics of the optical system of the second radiometer (RD8) is 2. t ・πC” ' El=K z
・El ・・・・・・・・・(
2) However, K z −k x ・πC! It is.

From equation (2), E, -E, /Kz Substituting this into the equation il+ gives E+ - + x (r-E(TL)+(1-r)
・Ex/nio) ;, E (Tt) K, r
K = 2 (3) In other words, if r and Kl are known to be 2, the total radiant energy E captured by the first radiometer (RDI) and the second radiometer ( E (Tt ) can be determined by measuring the total radiant energy E2 captured by RD, ).

Since the emissivity εL of the power transmission line (2) is a constant less than 1 specific to the transmission 1vA (2), r, , ,K.

If this is known, the radiant energy E (TL) of the power transmission line (2) itself can be determined by measuring E+ and Ex.

Then, from the value of E(TL), the temperature TL of the power transmission line (2) itself can be calculated using Blank's radiation law.

Calibration method> Now, Kl - is + ・a'b, and Kg = kz
- πC8, and finding + and Kz on this is called calibration.

The first measurement area (A,
) is the temperature of a calibration reference black body having an area equal to the area aXb of ). In the case of a black body, the emissivity is 5L-1.

The total radiant energy E, / emitted from this blackbody and captured by the first radiometer (RDI) is: , E1' = 1
・a-b-t, ・E(Ts)=K I-E
K1 can be found by separately obtaining (Ts) E(Ts)E+' and E(Ts).

For the total radiant energy B, / emitted from the blackbody and captured by the second radiometer (RDi), the second measurement area (
At), and the area of the second measurement area (A2) is πC1, so Eo′- ・πc” −
K2 can be found by separately obtaining E CTs )=K t −E (T s ) E(Ts) Bt ′ and E (Tx ).

The area ratio r is 8 or more, which can be determined at times when installing, so + + Kg is determined for tL, r, and E+,
By measuring Ex, E(TL ”
) is determined, and the temperature TL of the power transmission line (2) is determined from this E(TL) based on Blank's radiation law.

Isamu Oketsu Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 4 to 13.

FIG. 4 is a configuration diagram of the first radiometer (RDI).

First, the radiation measuring means will be explained.

In Figure 4, (6) is a glass window, (7) is a dust filter, (8) is a concave mirror with an opening (8a) in the center and a reflective part around the periphery, and (9) is a glass window (6). ) and a concave mirror (8), and is a convex mirror with a reflective part around its periphery. This convex mirror (9) has a smaller diameter than the concave mirror (8).

(10) is an aperture placed between convex mirror (9) and concave mirror (8), (11) is a chopper placed behind concave mirror (8), and (12) is immediately after tipper (11). Field stop located in the imaging plane, (13)
is Ge placed immediately after the field stop (12)
The condenser lens of the system, (14) is the condenser lens (
13) is the first detector placed immediately after.

Concave mirror (8), convex mirror (9), condenser lens (13)
) are coaxial. On its common optical axis, an aperture (10), a field stop (12).

The central axis of the first detector (14) is located.

The measurement system configured as described above is a Cassegrain type consisting of a concave mirror (8) and a convex mirror (9), and the concave mirror (8) and convex mirror (9) have a focal depth of 1.5 to 2 m at the center. Fixed (see Figure 2).

The dust filter (7) is made of polyethylene film, but may be made of Zn5e.

The aperture (10) cuts flare light (noise light) and has an annular window (10a).

The chisifuba (11) is used to increase the S/N ratio of the radiation signal by rotating it in front of the field stop (12), and its chopping cycle is 2.
It is about 0Hz.

The field stop (12) is the feed 1t to be measured.
This is for determining the first measurement area (Al) for &ff(2). That is, field stop (12
) is placed on the imaging plane of the power transmission line (2), and the transmission! ! With the statue of (2) placed in the center,
A window (12a) having a similar shape to the measurement area (At) is formed.

This window (12a) corresponds to the transmission region in the configuration of the invention. FIG. 5 shows the state of the field stop (12).

This field stop (12) is the first detector (14)
Field stop (12
) and the first detector (14).
3), the first detector (14) is placed close to the field stop (12), and all of the radiation that has passed through the field stop (12) is directed to the first detector (14). I try to collect them. As the first detector (14), a thermocuff pull, a thermomobile, or the like is used.

The first detector (14) usually has uneven sensitivity in its circumferential direction, but all of the radiation that has passed through the field stop (12) is transferred to the first detector (14) by the condenser lens (13). power lines (2
) is located in the first measurement area (A, ),
It is always possible to perform measurements with full sensitivity.

Note that due to the presence of the condenser lens (13), the first
An image of the aperture (10) is arranged onto the detector (14). This condenser lens (13)
is Ge-based, but may be Zn5e-based or Si-based.

However, the gelatin beetle has a sufficiently high refractive index,
Because it is possible to create a condenser lens with a high reduction ratio,
It is preferable to use a Ge-based condenser lens.

This first radiometer (RD+) has a condenser lens (13
), it is a radiometer directly related to the present invention.

Next, the finder system will be explained.

As shown in Figure 4, behind the glass window (6), a concave mirror (
8) is arranged concentrically. This objective lens (15
The convex mirror (9) is formed by depositing Au, Ag, Al, etc. around the surface of the mirror (9).

Between the convex mirror (9) and the aperture (10), there is a
A mirror (16) is arranged at an angle of 5 degrees, and the reflected light from this mirror (16) is directed to a pentaprism (17).
).

The structure is such that the light emitted from the pentaprism (17) passes through the index plate (1) and enters the eyepiece (19).

The index plate (18) is placed at the position where the objective lens (15) forms an image. A frame (18a) indicating the first measurement area (Al) is formed on the index plate (18). Inside this frame (18a), the area ratio r (r=
A scale is formed to serve as a guide for determining D/b).

Immediately before the indicator board (1 day), the digital temperature display section (2
0) is placed. FIG. 6 shows the condition of the indicator plate (18).

The above is the configuration of the finder system, which is configured so that the finder image and the measured temperature of the power transmission line (2) can be confirmed simultaneously.

The focal lengths of the measurement system and finder system are the same (for example, f-60, 76n). Therefore, even if the concave mirror (8), convex mirror (9), and pentaprism (17) are moved integrally along the optical axis for focusing, parallax (deviation in field of view) will not occur.

FIG. 7 is a configuration diagram of the second radiometer (RDz).

The configuration of the second radiometer (RD-L) is the same as the first radiometer shown in Figure 4.
The configuration is similar to that of a radiometer (RDI). However, there is no finder system and no condenser lens.

In Figure 7, (26) is a glass window, (27) is a dust filter, (2nd) has an opening (28a) in the center,
Concave mirror with reflective parts around the periphery, (29) is a glass window (2
6) and a concave mirror (28), it is a convex mirror with a reflective part around its periphery.

(30) is an aperture arranged between the convex mirror (29) and the concave mirror (28). A chopper (11) common to the first radiometer (RDI) shown in Fig. 4 is arranged behind the concave mirror (28).
is attached to the rotating shaft (11a).

(32) is a field stop placed on the imaging plane immediately after the chopper (11), and (34) is a second detector placed immediately after the field stop (32).

A convex mirror (29) is formed by depositing Au, Ag, A2, etc. around the surface of a cemented objective lens (35) consisting of a negative lens and a positive lens, which is placed behind the glass window (26).
) is formed. The concave mirror (28) and convex mirror (29) are the concave mirror (8) and convex mirror (9) of the first radiometer (RDI).
), it is fixed at the center of the focal depth of 1.5-2 m (see Figure 2).

The field stop (32) is for determining the second measurement area (A2) for the background. That is, the field stop (32) is formed with a window (32a) having a similar shape to the second measurement area (AX). FIG. 8 shows the state of the field stop (32).

This field stop (32) is the second detector (34)
Because it is small compared to the field stop (32), there is no need to place a condenser lens between the field stop (32) and the second detector (34), and all of the radiation that has passed through the field stop (32) can be transferred to the second detector (34). can be collected in.

The second detector (34) also usually has uneven sensitivity in its circumferential direction, but since it captures radiation from the bank ground, it can always measure the original with full sensitivity. It becomes.

FIG. 9 is a block diagram of a signal processing system related to the radiation thermometer (A).

In FIG. 9, (41) is the first optical system consisting of a concave mirror (8), a convex mirror (9), etc. in the first radiometer (RDI) shown in FIG. 14
) are placed. (42) are the concave mirror (28) and convex mirror (2) in the second radiometer (RDt) shown in Figure 7.
9), etc., and a second detector (34) is arranged behind it.

The chopper (11) shown in Figures 4 and 7 is placed in front of both detectors (14) and (34)! This chopper (11) is connected to the motor (Ila) via the rotating shaft (Ila).
43). This motor (43) is connected to a motor driver (44).

A preamplifier (45) connected to the first detector (14) and a preamplifier (46) connected to the second detector (34)
is connected to the signal processing circuit (4) via the changeover switch (47).
8). The signal processing circuit (48) is A/
It is connected to a D converter (49).

The above first optical system (41) and first detector (14).

Preamplifier (45), second optical system (42), second detector (34), preamplifier (46), motor (43)
), motor driver (44), signal processing circuit (48)
), A/D converter (49), etc. are radiation thermometers (A)
This constitutes the radiation measuring section (a) in.

This measuring section (a) is connected to a power source (5) using a solar cell via a measuring switch (50).

By turning on the measurement switch (50), the motor driver (44), preamplifier (45), and (46) are activated.

A signal processing circuit (48) and an A/D converter (49) are configured to be driven.

Microcomputer CPU (Central Processing Unit) (5
1) is connected to a power source (5) via a power switch (52). The CPU (51) is connected to an A/D converter (49) via a pass line.

Emissivity setting section (53), transmittance setting section (54), area ratio setting section (55), and temperature display section driver (56)
is connected.

The temperature display section (20) shown in FIG. 4 is connected to the temperature display section driver (56). This temperature display section (20)
uses an LCD (liquid crystal display).

The CPU (51) has a signal line that controls on/off of the measurement switch (50). (57) is the CPU (
51) is a manual switch connected to.

A data receiver (58) and a data transmitter (59) are connected to the CPU (51).

These data receiver (58) and data transmitter (59) are connected to activation switches (60) and (
61) to the power supply (5).

The CPU (51) has activation switches (60), (6
1) has a signal line for on/off control.

The overall configuration described above is a radiation thermometer (A).

Data receiver (58) in this radiation thermometer (A)
and a data transmitter (59) are connected to optical links (4a) and (4b), respectively. Both of these optical links (4a), (4b
) is the bidirectional optical link (4) shown in Figure 2.
).

Normally, in order to suppress the overall current consumption of the radiation thermometer (A) (for example, 100 mA or less), a power switch (
Turn on only 52) and turn on the CPU (51) and electric power (5)
It is connected to the CPU (51) and is supplied with Nomini 11 flow.

fallen Next, the operation of this embodiment will be explained.

<How to dig it up> First, the procedure for scooping up the radiation thermometer (A) onto, for example, the high-pressure steel tower (1) will be explained.

First, place a radiation thermometer (A) directly above the power transmission line (2).
Temporarily attach it to the high voltage tower (1).

Next, look through the eyepiece (19) in the finder system and place the radiation thermometer (A) so that the image of the power line (2) is located at the center of the frame (18a) (7) of the finger Ivi (18).
), and fixedly install the radiation thermometer (A) on the high-pressure tower (1).

As described above, the installation work can be easily performed on the high-voltage steel tower (1) while targeting the power transmission line (2) to be measured.

<Initial setting> Radiation from the power transmission line (2) and bank ground is
First, it is reflected by the concave mirror (8), and the reflected light is reflected by the convex mirror (9).
) and passes through the aperture (1o), and an image of the power transmission line (2) is formed at the field stop (12).

On the other hand, the image of the aperture (10) is the condenser lens (1
3) onto the first detector (14).

On the other hand, radiation from the bank ground first passes through the concave mirror (
28), the reflected light is reflected by the convex mirror (29), passes through the aperture (30), passes through the window (32a) of the field stop (32), and is transmitted to the second detector (34).
).

Next, within the first measurement area (A1), the area ratio r occupied by the power transmission line (2) and the bank ground is investigated. That is, the area ratio r is determined by looking at the scale formed on the frame (18a) of the index plate (18). And the area ratio r
is set in the area ratio setting section (55).

Further, the emissivity ε of the power transmission line (2) is set in the emissivity setting section (53), and the transmittance of air is set in the transmittance setting section (54).

Figure 10 (A) shows the first measurement area (A,) and second measurement area (A2) when the depth of focus is 1.5m.
Moreover, the state of the 1st measurement area (A1) and the 2nd measurement area (A2) when the depth of focus is 2.0 m is shown in the same figure (B).

The first measurement area (A,) and the second measurement area in the case of Figure 1O (A)
The area ratio between the measurement area (A, ) and the area ratio between the first measurement area (A, ) and the second measurement area (A2) in the case of FIG.

However, in the case of FIG. 10(A), the first measurement area (AI
) The ratio rlx()+/b+ between the long side b+ of the power transmission line and the diameter of the power transmission *(2), and the long side bt of the first measurement area (A, ) and the power transmission line in the case of (B) in the same figure. The ratio rz=Dt/bz of the radius in (2) is different.

That is, DI-D, -D, and b, <b.

Therefore, r, > r.

In this way, if r and r2 are different, the total radiant energy E captured by the first radiation needle (RDI) determined by equation (1)
The values of , will also differ.

Therefore, the power transmission line (2) in the first measurement area (A,)
It is necessary to set the area ratio r used in the calculation according to the ratio of the radiation area from the background to the radiation area from the background. This setting is performed in the area ratio setting section (55).

Next, the problem of spectral transmittance of air will be explained.

FIG. 11 shows the relationship between the spectral transmittance of air and the wavelength of radiation.

As is clear from FIG. 11, there are absorption bands for Cot, H, and O in wavelength regions of 8 μm or less and 14 μm or more. Therefore, the first radiation needle (RDI) and the second radiometer (R
The spectral transmittance for Dx) is limited to a wavelength range of approximately 8-14 μm. Within this range, the air transmittance is set by the transmittance setting section (54).

Figure 12 shows the first detector (14) and the second detector (3).
4) shows the characteristics of relative sensitivity [%] with respect to wavelength cμm].

Note that the emissivity ε of the power transmission line (2) is determined by an appropriate method, and is set in the emissivity setting section (53).

<Operation check> Various settings are completed as described above. In this case, the data receiver (58) and the data transmitter (59) include an optical link (4a),
(4b) is not connected.

When the manual switch (57) is turned on in this state, the CPU (51) turns on the measurement switch (50). That is, from the data receiver (58) to the CPU (51)
or even if there is no command to the data receiver (
5B) and the data transmitter (59) are not yet connected, the temperature of the power transmission line (2) can be measured by turning on the manual switch (57).

The measurement operation is as follows.

The CPU (51) turns on the measurement switch (50), and then switches the changeover switch (47) to the preamplifier (46) side.

Radiation of only the bank ground from the second measurement area (A2) is incident on the second detector (34) through the second optical system (42) of the second radiometer (RD2).

The second detector (34) converts the incident radiation into an analog signal. The analog signal is amplified by a preamplifier (46), subjected to predetermined processing in a signal processing circuit (48), and then output to an A/D converter (49).

The A/D converter (49) converts the analog signal into a digital signal and outputs it to the CPU (51). When the A/D conversion is completed, an A/D conversion completion signal is output from the A/D converter (49) to the CPU (51).

The CPU (51) switches the changeover switch (47) to the preamplifier (45) side based on this completion signal.

Then, the power transmission line (2) and background radiation from the first measurement area (AI) pass through the first optical system (41) of the first radiometer (RDI) and reach the first detector (
14).

The first detector (14) converts the incident radiation into an analog signal. The analog signal is amplified by a preamplifier (45), subjected to predetermined processing in a signal processing circuit (48), and then output to an A/D converter (49).

The A/D converter (49) converts the analog signal into a digital signal and outputs it to the CPU (51). When the A/D conversion is completed, an A/D conversion completion signal is output from the A/D converter (49) to the CPU (51).

The CPU (51) executes a predetermined calculation based on this completion signal to calculate the temperature TL of the power transmission line (2).

Next, the CPU (51) controls the temperature display unit driver (5
6) The temperature TL calculated by driving ' is displayed on the temperature display section (20
) for digital display.

After calculating the temperature TL, the CPU (51) captures the radiation from the first detector (14) while keeping the changeover switch (47) connected to the preamplifier (45) side, and performs the same operation as described above. Repeat the action.

When the temperature TL of the power transmission line (2) changes, the temperature displayed on the temperature display section (20) also changes accordingly.

In this way, the operation of the radiation thermometer (A) can be checked and calibrated with the radiation thermometer (A) alone.

These operations can be performed much more quickly and easily than in the conventional case.

<Normal operation> Data receiver (58) and data transmitter (
59), an optical link (43).

The operation after connecting (4b) will be explained.

When the manual switch (57) is turned on, the same operation as in the above-mentioned initial setting is executed regardless of whether a command signal is input to the data receiver (58) or not. .

When the manual switch (57) is turned off,
The CPU (51) intermittently turns on and off the activation switch (60) of the data receiver (58).

When a measurement command signal is input to the data receiver (58) via the optical link (4a) while the power switch (60) is on, the signal is sent to the CPU (51).
) is done manually.

After that, the CPU (51) performs the same operation as described above to calculate the temperature TL of the power transmission line (2). After the calculation, the power switch (61) of the data transmitter (59) is turned on, and the calculated temperature data is sent to the optical link (4b) via the data transmitter (59).
Send serially by .

In this case, the temperature is not displayed on the temperature display section (20).

However, even in this case, the temperature display section (20) may be configured to display the measured temperature TL.

In particular, it is preferable to display this immediately after switching from manual to automatic.

FIG. 13 shows a flowchart of the above operation. The operation based on this flowchart will be explained below.

When the power switch (52) is turned on, the flow starts from step #1. In step #1, it is determined whether the manual switch (57) is on. If it is on, the process moves to step #2 and it is determined whether the measurement switch (50) is on. If it is off, the process moves to step #3 and the measurement switch (50) is turned on.

Next, in step #4, each emissivity setting section (53)
, the transmittance setting section (54), and the emissivity and air transmittance set in the area ratio setting section (55).

Load area ratio data.

Next, in step #5, the radiation of only the bank ground is measured by the second radiometer (RD), and in step #6
The first radiometer (RDI) measures radiation from the power transmission line (2) and radiation from the grasshopper ground.

Based on the measured radiation data, the temperature TL of the power transmission line (2) is calculated in step #7.

In step #8, it is determined whether the manual switch (57) is still on.

If the on state continues, the process moves to step #9, and the temperature display driver (56) is driven to display the calculated power transmission line (
The temperature TL of 2) is displayed on the temperature display section (20).

After that, the process returns to step #6 and the first radiometer (RD
Radiation measurement by , ) Calculation of temperature TL - Judgment of manual switch (57) = A The routine of displaying degrees TL is repeatedly executed.

In this case, the reason for not returning to step #5 is that the background temperature hardly changes, and once measured,
The intensity of radiation from the bank ground can be considered constant,
This is because the data can be used repeatedly.

If it is determined in step #8 that the manual switch (57) is turned off, step #1
0, and the calculated temperature TL data is sent to the optical link (4b) via the data transmitter (59).
Then, the process moves to step #11 and is idled for a certain period of time in order to wait for input of a measurement command signal from the outside.

After idling ends, the measurement switch (50) is turned off in step #12, and in step #13 it is placed in a halt (stopped) state, waiting for input of a measurement command signal from the outside.

If an external measurement command signal is input to the data receiver (58) in the idling state of step #11, the process does not proceed to step #12 and step #2
→ Execute the routine #6 → #7 → #8-#10 → #11. This is the case when there is a measurement command signal from outside immediately after the end of one measurement, and the power transmission line (2
) is measured again and transmitted.

Further, in the judgment in step #1, if the manual switch (57) is off, the process moves to step #14,
Set to halt state.

In the halt state of step #13 or step #14, when an external measurement command signal interrupt occurs, steps #2 → #3 → #4 → #5 → #6 → #
Execute the routine 7→#8→#10-#11→#12→#13. This is the case when there is a measurement command signal from outside during normal times, and the power transmission line (2) at that time
The temperature T, is measured and transmitted.

Note that the transmission region referred to in the configuration of the invention refers not only to the window (12a) of the field stop (12), that is, the aperture;
It may be made of a transparent material.

Fourth coming According to the present invention, the following effects are achieved.

Since the area of the transmission region is larger than the image of the measurement object formed on the imaging plane of the imaging optical system, the measurement area at the position of the measurement object becomes larger than the measurement object due to the transmission region.

Therefore, the object to be measured can be easily placed within the measurement area, and even if the object to be measured moves slightly, the object to be measured can always be kept within the measurement area.

That is, even if the measurement object moves, the radiation energy from the measurement object that enters the detector can be kept constant.

On the other hand, the area of the transmission region is configured to be larger than the image of the measurement target formed on the imaging plane, and a condenser lens is placed between the transmission region and the detector. Since the condenser lens is configured to form a reduced image of the aperture on the detector, the detector captures all of the radiant energy that passes through the aperture. Therefore, there is no need to use a detector with such a large area.

Therefore, the radiation thermometer can be manufactured easily and is cost-effective.

In addition, as mentioned above, it is normal for a detector to have uneven sensitivity depending on its part, and the larger the area, the more severe the unevenness in sensitivity is. Since it is small, there is no need to be adversely affected by uneven sensitivity.

In addition, since all of the radiant energy that passes through the aperture is captured by the detector, even if the object to be measured moves and the projected position of its image on the detector changes, the detector's full sensitivity remains unchanged. Measurement becomes possible.

As described above, according to the present invention, there is no need to cause an error in the measured temperature, despite the unevenness of the sensitivity of the detector and, therefore, despite the movement of the measurement target, and the temperature measurement can be carried out at a very high level. Can be done with precision.

[Brief explanation of drawings]

Figure 1 is a schematic front view showing the installation status of the radiation thermometer;
Fig. 2 is an explanatory diagram of the measurement situation, Fig. 3 is an explanatory diagram of the measurement area, and Figs. 4 to 13 relate to an embodiment of the present invention.
Figure 4 is a diagram of the configuration of the first radiometer, Figure 5 is a state diagram of the field stop of the first radiometer, Figure 6 is a diagram of the index plate of the finder system, and Figure 7 is the configuration of the second radiometer. Figure 8 is a state diagram of the field stop of the second radiometer, Figure 9 is a block diagram of the signal processing system related to the radiation thermometer, and Figure 10 is (
A) and (B) are the first measurement area and the second measurement area, respectively.
11 is a characteristic diagram of air transmittance with respect to wavelength, FIG. 12 is a characteristic diagram of relative sensitivity of the temperature sensor with respect to wavelength, and FIG. 13 is a flowchart. (A)...Radiation thermometer (RD,)...First radiometer (AI)...First measurement area (2)...Power line (10)...Aperture (12)...・Field stop (12a)...Window (33 passband) (13)...Condenser lens (14)...First detector (41)...Optical system (imaging optical system) Fig. 1 ; Figure 3, Figure 5, Figure 6, Figure 4! #7 Figure RD2 Figure 110 (A) (B) 1985 Patent Application No. 246861 23 Name of Invention Radiation Thermometer, 3. Relationship with the person making the amendment Patent applicant address Osaka Kokusai Building, 2-30 Azuchi-cho, Higashi-ku, Osaka Name (607) Minolta Camera Co., Ltd. Representative Hideo Tajima 4, Agent (1) Specification page 12 In lines 7 to 10, "Since it is a constant, we can find . . . . J is an r constant, so that The energy E(T1.) can be found.'' (2) Correct "equal to" in line 19 of page 12 to "greater than J." (3) Correct reL=IJ in line 1 of page 13 to "e. #1". (4) In the second line of page 15, "rce system" is corrected to "Ge's". (5) "Depth of focus" in lines 11 to 12 of page 15 is corrected to "measurement distance -." (6) "Film" in line 14 of page 15 is corrected to "board." (7) "It's a thing, it's a degree." in the first and second lines of page 16 is an r thing. ” is corrected. (8) "In other words,..." on page 16, lines 5 to 9.
...is formed. ” to be deleted. (9) [First detector (
14) While placing......delete ". (lO) In the third line of page 17, "in the circumferential direction" is corrected to "within the detection area." (11) On page 17, lines 6 to 14, “It is okay to use all of the radiation.” was changed to “collect all of the radiant energy, and the first detector (14) Since the image of the aperture (10) is formed on top of the transmission line, measurements can always be made with the same sensitivity no matter where the power transmission line (2) is located within the first measurement area (A1). This condenser lens (13) is made of Ge, but Zn5
It may be e or Si. ” is corrected. (12) “Ge-based” on page 17, line 17
Since it is possible to r, it is corrected to ``Ge''. (13) Page 18, line 6, page 20, lines 14 to 15
Correct "Surface periphery" in the lines to "Rear surface periphery J." (14) "Measurement system and...
・・・・・・Does not occur. '' should be corrected to ``Since the optical axes of the measurement system and the finder system are aligned and their focal lengths are also the same, parallax (displacement of field of view) does not occur.'' (15) “In the circumferential direction” on page 21, line 12 of the same
should be corrected to "within the detection area." (16) Page 21, lines 14-15 “Radiation...
It becomes... " is corrected to "There is no effect because it is only radiated energy." (17) On page 23, lines 8 and 9, [the CPU (central processing unit) (51) of the microcomputer is]
The r microcomputer (51) corrects it to j. (18) “Through the pass line,
Correct J to ``■ through line 10. (19) Correct ``(for example, 100mA
(below), delete ". (20) Delete "It can be done as described above" from lines 14 to 16 on page 25. (21) Delete "Examine the area ratio r" on page 26, lines 12 to 14. (22) On page 26, line 18, "air transmittance" is corrected to "optical system transmittance". (23) "Page 26, line 19 and page 27, line 1"
Correct "depth of focus" to "r measurement distance" respectively. (24) "Radiation" on page 28, line 4 is corrected to r radiant energy 1. (25) ``Second measurement area (A7)......Delete j'' in lines 16 to 19 of page 29. (26) Page 11 of page 30 Line ~ Line 14 “Then...
・・・・・・・・・It is incident. ” to be deleted. (27) "Convert." on page 30, line 16 of the same page is corrected to "converting. J." (28) "These...
········It can be carried out. ” to be deleted. (29) Correct "From manual to automatic" in line 6 of page 33 to "j from operation check to normal operation." (30) Change "air permeability," in line 20 of page 33 to "j".
The transmittance of the optical system is corrected. (31) On page 38, lines 3 and 4, “The detector...
...I don't have to take it. "Even if the object to be measured moves and the position of its image on the aperture transmission range changes, a reduced image of the aperture is always formed on the detector, so there is no adverse effect due to uneven sensitivity. (32) "In addition,..." on page 38, lines 5 to 9.
...It becomes possible. ” to be deleted. (33) "Movable" in line 12 of page 38 is corrected to "move." (34) Page 23, line 10, line 19, page 24, line 1
Line, 3rd line, 8th line, 19th line, 20th line, page 29, line 5, 6th line to 7th line, 13th line, page 30th line 6th line, 7th line to 8th line Line, line 9, page 31, line 1, lines 2 to 3
line, 4th line, 7th line, 10th line, 32nd page, 10th line, 15th line, 16th line, 31st page, 1st line, 6th line, 7th line rcPU (51) J Corrected to r microcomputer (51) J, respectively. (35) Figure 9 of the drawings is corrected as shown in the attached sheet. 9. List of attached documents

Claims (3)

[Claims] (1) An imaging optical system that has an aperture that limits the flux of radiant energy, and an aperture formed on the imaging surface of this imaging optical system that is larger than the image of the measurement target that is formed on this imaging surface. a large-area transmission region; a detector of a radiant energy measuring means disposed behind the transmission region; and a detector disposed between the transmission region and the detector, for displaying a reduced image of the aperture on the detector. A radiation thermometer equipped with an imaging condenser lens. (2) The radiation thermometer according to claim (1), wherein the condenser lens is a germanium lens. (3) The radiation thermometer according to claim (1), wherein the condenser lens is a silicon lens.