JPH0763614A - Optical measurement device - Google Patents

Abstract

PURPOSE:To accurately measure temperature or the other optical characteristics by a small device. CONSTITUTION:Radiation energy from a radiation source 1 is divided into radiation energies having different irradiation areas by means of a rotary sector 3 having a plurality of different openings and the energies are applied to an object 5 to be measured. The radiation energies from the object 5 are made incident on a radiation detector 7 and the outputs thereof are made incident on a computing means 8. The emissivity, temperature and the other optical characteristics of the object 5 are calculated by utilizing the combination of the outputs corresponding to the openings of the rotary sector 3 in accordance with the surface condition or the like of the object 5 to be measured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical measuring device for measuring the temperature or other properties of a measuring object in which the influence of emissivity is removed.

[0002]

2. Description of the Related Art The applicant has, for example, Japanese Patent Publication No. 62-259.
Japanese Patent Laid-Open No. 72-72 proposes a method of measuring the emissivity and temperature from the output change when the distance between the comparative hot plate (auxiliary heat source, radiant source) and the measurement object is changed.

[0003]

However, when the comparative heating plate is driven, the device becomes large in size, the response time is slow, and the spatial distance between the measuring object and the device cannot be increased. .

SUMMARY OF THE INVENTION In view of the above points, an object of the present invention is to provide an optical measuring device which is a simpler device and accurately measures temperature, surface roughness of a measuring object and other optical properties.

[0005]

SUMMARY OF THE INVENTION The present invention rotates with a radiant source that emits radiant energy to a measurement object and a plurality of different apertures for varying the area of irradiation of the radiant energy from the radiant source. A rotating sector, a radiation detector for detecting radiation energy from a radiation source which irradiates a measuring object through the rotating sector, and output signals of the radiation detector for different apertures of the rotating sector. The optical measuring device is provided with a calculating means for calculating the temperature or other optical property of the measurement object using the combination of.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a structural explanatory view showing an embodiment of the present invention. In the figure, reference numeral 1 is a radiation source such as a light source, and the radiant energy emitted from this radiation source 1 is collected by a lens 2 and rotated by a motor M, which have different apertures 3a, 3b, 3c, as shown in FIG. An image is formed on a rotating sector (chopper) 3 having 3d, 3e, and 3f to form radiant energy of different irradiation areas, and a measuring object 5 is passed through a lens 4.
Is irradiated. The radiant energy reflected from the measuring object 5 and the radiant energy from the measuring object 5 are collected by the lens 6 and detected by the radiation detector 7, and the output signal thereof is subjected to various calculations by the calculating means 8 mainly composed of a microcomputer. Then, measurement calculation of optical properties such as emissivity, temperature, and surface roughness of the measurement object 5 is performed. Further, the temperature of the rotating sector 3 is measured by a sensor (not shown) if necessary, and the timing of each opening is also detected by a synchronous detector 30 which detects the cutouts 30a, 30b, ... Each output of the instrument 7 is separated and measured.

It is assumed that the emissivity of the measuring object 5 is ε, the temperature is T, the radiant energy of the radiant source 1 is Er, and the radiant energy corresponding to a black body at the temperature T is E (T).

When the rotating sector 3 rotates, radiant energies of different irradiation areas are sequentially projected onto the measuring object 5, but the output of the radiation detector 7 when there is no aperture is Eo, and an arbitrary different area S1, Output E for an aperture with S2
1, E2 (S1 is an opening larger than S2)
It becomes the following formula.

Eo = εE (T) (1) E1 = εE (T) + F1 (1-ε) S1 · Er (2) E2 = εE (T) + F2 (1-ε) S2 · Er (3) where , F1 and F2 are contribution factors related to the scattering of the radiant energy from the radiation source 1 on the surface of the object which is reflected by the measuring object 5 and enters the radiation detector 7. That is, the first term on the right side of the equation (1) is the radiant energy from the measurement object 5 itself,
The first term of the equations (2) and (3) is the radiant energy from the measuring object 5, and the second term is the radiant energy Er of the radiation source 1 irradiating the measuring object 5 with the areas S1 and S2 of the openings, respectively. It is the ratio of being scattered on the surface and being incident on the radiation detector 7 at the contribution rates F1 and F2.

Here, by subtracting the expressions (2) and (3) from each other, the following expression is obtained.

E1−E2 = (1−ε) (F1 · S1−F
2 · S2) Er Thus, ε = 1− (E1−E2) / {(F1 · S1−F2 · S2) Er} (4). Here, D = F1 · S1−F2 · S2,
If this D is known, E1 and E2 are measured quantities, S1, S2, Er
Is known, the emissivity ε can be obtained. This is calculated from the following formula.

By subtracting the equation (1) from the equation (2) and the equation (1) from the equation (3), the following equation is obtained.

E1-Eo = F1 (1-.epsilon.) S1.Er E2-Eo = F2 (1-.epsilon.) S2.Er By taking the ratio R, the following equation is obtained.

R = (E2-Eo) / (E1-Eo) = F2 / S2 / F1 / S1 (5) where D = F1 / S1-F2 / S2 and R = F2 / S2 /
The relationship with F1 and S1 is D = f (R) as shown in FIG.
It was experimentally found that there is a predetermined functional relationship with.
For example, D is given by a quadratic equation of D = aR ² + bR + C (a, b, and c are coefficients).

That is, since D is obtained from R and the other values on the right side of the equation (4) are obtained by measurement or the like, the emissivity ε can be obtained.

Since, for example, E (T) = Eo / ε (6) is obtained from the equation (1), the emissivity ε or the like is substituted into the equation (6) to obtain the temperature of the measuring object 5.

That is, at the time of measurement, as shown in FIG. 3, the functional relationship between D and R obtained by measurement D = f in advance.
(R), the radiant energy Er of the radiation source 1 and the like are stored in the memory of the calculating means 8.

Next, at the time of measurement, when the rotating sector 3 is rotated,
Output Eo when closed, outputs E1, E for various openings
Signals of 2, ... Are obtained, and the emissivity ε can be obtained by the equation (4) and the temperature T can be obtained by the equation (6) using the signals of the equations (1), (2), and (3).

Here, when the surface of the measurement object 5 has a strong specularity, the directivity of the radiant energy reflected by the surface is strong and a combination of small openings of the rotating sector 3, for example, openings 3e and 3f may be used. . On the other hand, when the diffusion property is strong, conversely, a combination of large openings of the rotating sector 3, for example, the openings 3a and 3b may be used.

Further, R = F2 · S2 // in the above equation (5)
It is also possible to obtain the measured value Ro of the surface roughness reference plate by using F1 · S1, and then calculate R / Ro to normalize and obtain the surface roughness.

FIG. 4 shows another embodiment of the present invention,
The same reference numerals as those in FIG. 1 denote the same components, and the radiant energy from the radiant source 1 is condensed by the lens 2 and rotated by the motor M. The rotating sector 3 has a plurality of openings as shown in FIG.
Then, the irradiation area of the radiant energy is changed, and the measuring object 5 is irradiated with the lens 4 through the half mirror 41. The radiant energy from the measurement object 5 is reflected by the half mirror 41 and is incident on the radiation detector 7, the output of which is input to the calculating means 8 and separated by the synchronization signal of the synchronization detector 30 of the rotating sector 3, The same calculation as above is performed, and the emissivity ε, the temperature T, and other optical properties are measured.

FIG. 5 shows another embodiment, in which the same reference numerals as those in FIG. 1 show the same components, and the radiant energy from the light source 1 is collected by the lens 2 and rotated by the motor M.
Image is formed on the rotating sector 3 having a plurality of apertures such as shown in FIG.
At 10 the light is projected onto the measuring object 5. The radiant energy reflected by the measurement object 5 is collected by the concave mirror 42, reflected by the convex mirror 43, passes through the opening 40 of the concave mirror 42, and the radiation detector 7
The output signal is separated by the calculation output 8 by the synchronization signal of the synchronization detector 30, the same calculation as described above is performed, and the emissivity ε, the temperature T, and other optical properties are measured.

As described above, various optical systems are conceivable, and the optical system is not limited to the above. Further, in the above example, the rotating sector 3 is placed on the image forming surface of the light projecting lens, but the same effect can be obtained by placing it at an arbitrary position, for example, in front of the light collecting lens.

[0024]

As described above, according to the present invention, the measurement is performed through the rotating sector having different apertures. Since the rotating sector rotates at a high speed, emissivity, temperature, surface roughness, and other optics are measured. The physical properties can be measured with a small and compact structure and with high responsiveness. In addition, since the aperture signal is measured in combination according to the surface condition of the measurement object, it is less likely to be affected by the surface roughness,
Highly accurate measurement is possible.

[Brief description of drawings]

FIG. 1 is a structural explanatory view showing an embodiment of the present invention.

FIG. 2 is a structural explanatory view showing an embodiment of the present invention.

FIG. 3 is an operation explanatory diagram showing an embodiment of the present invention.

FIG. 4 is a structural explanatory view showing another embodiment of the present invention.

FIG. 5 is a structural explanatory view showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Radiation source 2, 4, 6 Lens 3 Rotation sector 5 Measuring object 7, 71, 72 Radiation detector 8 Computation means

Claims (1)

[Claims] 1. A radiant source that emits radiant energy to a measurement object, a rotating sector having a plurality of different openings for changing an irradiation area of the radiant energy from the radiant source, and the rotating sector. Of the measuring object using a combination of a radiation detector for radiating the measuring object via the radiation energy from the radiation source reflected and the output signal of the output of the radiation detector for different apertures of the rotating sector. An optical measuring device comprising: a calculating means for calculating temperature or other optical properties.