JPH051954A - Temperature distribution measuring device - Google Patents

Abstract

PURPOSE:To simply measure the temperature distribution in the space with high precision by providing a chopping means intermittently interrupting the infrared beam fed to an array sensor and a driving means rotating the array sensor in steps, and measuring the maximum values of detection sections at each chopping with a peak hold circuit. CONSTITUTION:A silicone infrared lens 2 for converging the light to a pyroelectric infrared array sensor 1 provided with multiple light reception sections in lines is provided on a rotation section 4, and a chopper 3 intermittently interrupting the infrared beam fed to the lens 2 is provided. The rotation section 4 is connected to a stepping motor 5. When the longitudinal direction of the array sensor 1 is set to the vertical direction and the chopper 3 is driven at 10Hz, for example, the distribution of the vertical radiation heat quantity, i.e., temperature distribution, in the direction faced to the sensor 1 and the lens 2 at every 1/10sec can be measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radiation temperature distribution measuring device using a pyroelectric infrared sensor.

[0002]

2. Description of the Related Art In recent years, in security and air conditioning control, there is an increasing demand for measuring the temperature distribution in a room in order to detect the presence or absence of a person in the room and the amount of activity.

Conventionally, as a device for measuring a temperature distribution in a space using infrared rays, there is a method for obtaining a temperature distribution using a two-dimensional quantum solid-state imaging infrared sensor.

On the other hand, methods for obtaining the spatial temperature distribution using a pyroelectric sensor are disclosed in Japanese Patent Laid-Open Nos. 64-88391 and 5-88391.
7-185695, Japanese Patent Laid-Open Nos. 2-183752, 2
As described in Japanese Patent Publication No. 196932, etc., there is a method in which a single pyroelectric sensor is used to mechanically scan in the vertical and horizontal directions to detect the input energy in each direction and obtain the temperature distribution.

[0005]

In the case of the quantum type sensor, the measurement temperature accuracy and resolution are high, but since the sensor portion needs to be cooled, it becomes expensive and is not suitable for use in household appliances. Is. On the other hand, the latter one using the pyroelectric sensor has a problem that the spatial resolution and the temperature resolution are low due to the problem that the sensor sensitivity is low and the complexity of the mechanism and the complexity of the signal processing.

The present invention has been tried in view of the above problems, and provides a low-cost, compact and highly reliable temperature distribution measuring device using an infrared array sensor such as a pyroelectric sensor.

[0007]

SUMMARY OF THE INVENTION The present invention has an array sensor for detecting infrared rays, a chopping means for intermittently blocking the infrared rays entering the sensor section, and a driving means for rotating the sensor array stepwise. The maximum value of each detection section is measured by a peak hold circuit for each chopping.

[0008]

With the above configuration, the amount of incident infrared light, that is,
By selecting the sensor output maximum value corresponding to the measured object temperature by the electric circuit, it becomes possible to easily and accurately measure the temperature distribution in the space.

[0009]

1 shows a schematic structure for explaining an embodiment of the present invention. A pyroelectric infrared array sensor 1 in which a plurality of light receiving portions are provided in a line on a rotating portion 4 is shown. When,
A silicon infrared lens 2 for collecting infrared rays on the array sensor 1 is provided on the front surface thereof, and a chopper 3 for intermittently blocking infrared rays incident on the lens 2 is provided on the front surface of the lens 2. The rotating unit 4 is mechanically connected to the stepping motor 5.

Now, if the long axis direction of the array sensor 1 is set in the vertical direction and the chopper is driven at 10 Hz, it will be 1/10 s.
For each ec, the distribution of the amount of radiant heat in the column in the direction in which the sensor and the lens face the body, that is, the temperature distribution can be measured.

FIG. 2 shows a schematic diagram of the measuring circuit. The output signal from the sensor 10 having a plurality of elements is filtered by the filter circuit 11 to remove noise, and then amplified by the amplifier circuit 12, and the peak hold circuit 13 holds the maximum output value. This maximum output value corresponds to the amount of incident infrared light and corresponds to the temperature of the measuring object. The maximum output value of each sensor element is selected by the multiplexer 14, converted by the A / D converter 15, and stored in the memory unit of the CPU 16 as data. The drive timing of the chopper 19 and the stepping motor 18 is the I / O board 1
It is controlled by the CPU 16 via 7. Timings of the chopper 19, the stepping motor 18, and the peak hold are synchronized by the clock generation circuit in the CPU.

FIG. 3 shows the timing of each signal. Figure 3
In (a), the drive signal of the stepping motor,
(B) shows an infrared incident state by chopping,
(C) is the analog output signal waveform of the sensor, (d)
Is a waveform after peak hold of 63.

Next, the measurement procedure will be described with reference to the A / D conversion flowchart shown in FIG. First, when the signal of the chopper becomes HIGH, the chopper opens, and the infrared ray enters, the peak holder is set,
The maximum value of the sensor output signal is retained. Next, at the timing when the chopper signal becomes LOW, the maximum value of each sensor element output signal is sequentially selected and fetched by the multiplexer, A / D converted, and data is transferred to the CPU. This process is executed until all elements are completed. After finishing all the elements, reset the peak holder and put it in a standby state. As shown in FIG. 3, the timing of this process is executed during Δt, and is completed during the initial period when the chopper is in the closed state.

The above embodiment has been described with respect to the case of measuring the two-dimensional temperature distribution by changing the measuring direction by the rotating mechanism, but it is naturally applied to the one-dimensional temperature distribution measurement without the rotating mechanism. It is possible.

An example of the peak hold circuit 13 used in this experiment is shown in FIG. 5, but it is not particularly limited to this embodiment as long as it is a circuit having a peak hold function.

[0016]

As described above, according to the present invention, in the temperature distribution measuring device having the array sensor for detecting infrared rays and the chopping means for intermittently blocking the infrared rays incident on the sensor portion, the above-mentioned operation is performed for each chopping. Since the maximum value of each detector is measured by the peak hold circuit, it has an effect that the temperature distribution in the space (radiant heat distribution) can be measured simply and easily by the measuring circuit. .

[Brief description of drawings]

FIG. 1 is a schematic view of a temperature distribution measuring device according to an embodiment of the present invention.

FIG. 2 is a schematic diagram of a measurement circuit in the device.

FIG. 3 is a timing chart of electric signals in the device.

FIG. 4 is a flowchart of signal processing in the device.

FIG. 5 is a schematic diagram of a peak hold circuit in the device.

[Explanation of symbols]

1 Infrared array sensor 2 infrared lens 3 chopper 4 rotating parts 5 Stepping motor 10 sensors 11 Filter circuit 12 amplifier circuit 13 Peak hold circuit 14 Multiplexer 15 A / D converter 16 CPU 17 I / O board 18 stepping motor 19 chopper

Claims (3)

[Claims] 1. An infrared array sensor having a plurality of light receiving portions for detecting infrared rays arranged in an array, and a chopping means for intermittently blocking infrared rays incident on the sensor portion, and each of the detections for each chopping. Temperature distribution measuring device characterized in that the maximum value of the temperature is measured by a peak hold circuit 2. An infrared array sensor is provided with a driving means for rotating the body surface direction stepwise, and chopping is performed one or more times for each body surface direction, and the maximum value of each detection section is peak-held for each chopping. The temperature distribution measuring device according to claim 1, wherein the temperature is measured by a circuit. 3. The temperature distribution measuring device according to claim 1, wherein the peak hold circuit and the chopper drive or rotation drive are synchronized with each other by receiving a signal from the same clock generation circuit.