JPH0645216Y2 - Portable far infrared detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a far-infrared detector, and more particularly to a portable far-infrared detector that is convenient to carry.

[Prior Art] A spectrophotometer has been widely used as a device for detecting far infrared rays. The spectrophotometer is a device for measuring the absorbance at each wavelength of the absorption spectrum, and is composed of a light source, a spectroscope, a light receiving section, and the like, and the light receiving section is provided with means for keeping the light receiving element at a constant temperature.

[Problems to be Solved by the Invention] However, the spectrophotometer is intended to measure in detail and accurately the wavelength of light and the intensity of the light to be measured. Therefore, a high performance is required for the light receiving element, and for this reason, a means for keeping the light receiving element at a constant temperature as described above is required,
The device had to be a large stationary type. In addition, it is necessary to perform measurement using a sample, and the shape and the like of this sample are also limited, so that the measurement work cannot be performed easily.

[Means for Solving the Problem] The portable far infrared ray detector according to the present invention is made in view of the above-mentioned conventional problems, and is one portable box provided with a window through which light to be measured passes. Inside, a chopper that rotates at a predetermined cycle to chop the measured light, a motor for driving the chopper, a sensor including a pyroelectric element that detects far infrared rays contained in the measured light, and The rotation speed of the chopper is adjusted by varying the rotation of the motor in another box equipped with a light receiving / amplifying unit that includes an amplifier that amplifies the output of the sensor, and a meter that displays the output of the amplifier. Means for adjusting the sensitivity of the pyroelectric element, and a display / adjustment section accommodating the means for rectifying the power supplied to the motor and the amplifier. Spectral sensitivity characteristics of 6-1 The feature of the thickness is 5 μm, and the detector is downsized, and the intensity of far infrared rays can be measured more appropriately by utilizing the most effective wavelength range of far infrared rays.

As is well known, this pyroelectric element is a substance having a pyroelectric effect,
For example, it is composed of a crystal of LiTaO ₃ , and far infrared rays are detected by extracting the non-equilibrium charge on the crystal surface as a voltage change. That is, chopping is necessary because the effect is produced only when the temperature of the crystal surface changes. Further, generally, a sensor using a pyroelectric element is provided with a filter for cutting wavelength components other than far-infrared rays having a wavelength within a predetermined range and does not require a spectroscopic device. Also,
Since the pyroelectric element has almost constant sensitivity at room temperature, it does not require treatment such as cooling, and is smaller and cheaper than other infrared detecting elements.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is a light receiving / amplifying section and 2 is a display / adjusting section.

The light receiving / amplifying unit 1 includes a carrying handle 3 and a measured light L.
In a portable box 5 with a window 4 for passing
A chopper 6, a motor 7 for driving the chopper 6, a sensor 8 and an amplifier 9 are housed. In the light receiving / amplifying unit 1 created by the inventors, the size of the box 5 is 70 mm wide.
mm, height 140 mm, length 190 mm, and weight 0.5 kg.

In addition, the display / adjustment unit 2 includes a power supply rectification unit 11 in the box 10.
In which electric / electronic circuits such as the above are housed, and a panel surface 13 provided with a meter 12 for displaying the output of the amplifier 9 is provided with a rotation speed adjusting knob 14 of the chopper 6 and a sensitivity volume 15 of the sensor 8. Is. The display / adjustment unit 2 created by the inventors has a width of 200 mm, a height of 130 mm, a length of 150 mm, and a weight.
It was 1.2 kg.

The sensor 8 in the light receiving / amplifying unit 1 has a pyroelectric element 17 housed in a tube 16 of which one side is opened toward the window 4 of the box 5. The pyroelectric element 17 has a spectral sensitivity characteristic of 6 to 15 μm, which is the most effective wavelength range in far infrared rays. The output of the sensor 8 is input to the amplifier 9.

The chopper 6 is arranged between the opening of the cylinder 16 of the sensor 8 and the window 4 of the box 5, and the motor 7 is rotated so as to rotate at a predetermined cycle.
The light L to be measured is chopped by being rotationally driven by and periodically blocking between the opening and the window 4.

The motor 7 is connected to a drive power supply circuit (not shown) in the display / adjustment unit 2 via a cable 18, and the rotation speed adjusting knob 14
Rotation speed changes when is operated. The chopping frequency of the chopper 6 changes with the change in the rotation speed of the motor 7. Also, if you operate the sensitivity volume 15, the pyroelectric element
The sensitivity of 17 can be changed. That is, by operating the rotation speed adjusting knob 14 and the sensitivity volume 15, the spectral sensitivity of the sensor 8 can be adjusted to the optimum value.

[Effects of the Invention] As described above, the portable far-infrared ray detector according to the present invention employs a pyroelectric element as the far-infrared ray detecting element,
A light receiving / amplifying unit is configured by housing it in a portable box together with a chopper, an amplifier, and a motor. A box separate from this light receiving / amplifying unit is provided with a meter, a means for rectifying the rotation of the chopper, and a motor rotation speed. Since the means for adjusting and the means for adjusting the sensitivity of the pyroelectric element are provided, there is an effect that the light receiving / amplifying portion can be formed in a smaller size and lighter weight, and further, the most effective wavelength range of far infrared rays is used. By doing so, there is an effect that the intensity of far infrared rays can be measured more appropriately. In addition, there is an effect that the spectral sensitivity of the sensor can be adjusted to an optimum value for measurement.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing a first embodiment of the present invention. 1: Light receiving / amplifying section, 2: Display / adjusting section 4: Window, 5: Box 6: Chopper, 7: Motor 8: Sensor, 9: Amplifier 10: Box, 11: Power rectification section 12: Meter, 14: Rotation Speed control knob 15: Sensor sensitivity volume 17: Pyroelectric element, L: Light to be measured

Claims (1)

[Scope of utility model registration request] 1. A chopper for chopping the light to be measured by rotating at a predetermined cycle in a portable box provided with a window through which the light to be measured passes, a motor for driving the chopper, and the object to be measured. A sensor provided with a pyroelectric element for detecting far infrared rays contained in the measurement light, a light receiving / amplifying section provided with an amplifier for amplifying the output of the sensor, and a meter for displaying the output of the amplifier. In another box, means for adjusting the rotation speed of the chopper by changing the rotation of the motor, means for adjusting the sensitivity of the pyroelectric element, and means for rectifying the power supplied to the motor and the amplifier. A portable far-infrared detector characterized in that it comprises a display / adjustment section accommodating and a pyroelectric element having a spectral sensitivity characteristic of 6 to 15 μm.