JPH08285787A - Degradation degree diagnostic device - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a deterioration degree diagnosing device capable of diagnosing a deterioration degree without stopping the operation of an apparatus even for an object to be measured having an uneven surface. [Structure] Based on the output from the light quantity measuring unit 8, the reflection absorption difference or reflection absorption ratio between wavelengths is calculated from the reflection absorption intensity at each wavelength, and the deterioration degree of the DUT 11 and the reflection absorption difference between wavelengths are calculated in advance. Alternatively, the deterioration degree calculation unit 1 for performing a comparison calculation based on the relationship with the reflection absorbance ratio is provided, and the irradiation area 9a that is transmitted to the surface of the DUT 11 through the irradiation optical fiber 9 and the surface of the DUT 11 is measured. The width D of the light projecting / receiving area 12a in which the light receiving area 13a of the light receiving optical fiber 13 for receiving the reflected light 12 is overlapped with the unevenness periodic pitch P of the DUT 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deterioration degree diagnosing device, and more particularly to a deterioration degree diagnosing device for nondestructively measuring the deterioration degree of an object to be measured such as an insulating material and a structural material.

[0002]

2. Description of the Related Art A deterioration degree diagnosing device for evaluating the deterioration degree of an insulating material or a structural material such as a rotary motor is disclosed in JP-A-64-841
As described in Japanese Laid-Open Patent Publication No. 62-62, the irradiation light guided from a white standard light source through an optical fiber is reflected by a sensor section made of the same material as the insulating material, and the reflected light is detected through a light receiving optical fiber. However, the colorimetric calculation is performed based on the chromaticity or the chromaticity difference based on the L * a * b * colorimetric system. Here, L * represents brightness by a brightness index, a * and b * are called chromatic indexes,
It represents chromaticity, that is, hue and saturation. In addition, JP-A-3
As described in JP-A-226651, irradiation light guided from a white standard light source through an optical fiber is transmitted through a sensor section made of the same material as an insulating material, and the transmitted light is transmitted through an optical fiber for receiving light. A transmitted light type deterioration degree diagnosing device for detecting and performing colorimetric calculation based on the chromaticity or chromaticity difference based on the L * a * b * colorimetric system has also been proposed.

[0003]

However, in these conventional reflected light type and transmitted light type deterioration degree diagnosing devices, an irradiation optical fiber and a light receiving light are provided in an insulating layer in a device such as a rotating machine when the device is manufactured. It is necessary to embed the fiber and the sensor unit, respectively, and it is not applicable to existing equipment such as an existing rotating machine that does not embed them. Therefore, according to the same applicant as the present application, a light source unit that irradiates at least two or more types of monochromatic light having different wavelengths, and an irradiation that guides the irradiation light from the light source unit and irradiates the surface of the DUT. Optical fiber, a light receiving optical fiber that receives at least two types of reflected light having different wavelengths from the surface of the object to be measured, and light that calculates the amount of reflected light guided by the light receiving optical fiber After calculating the reflection absorbance at each wavelength based on the amount of reflected light output from the detection calculation unit and the light detection calculation unit, the reflection absorbance difference between each wavelength is calculated, and the calculation result and the degree of deterioration of the DUT in advance. There has been proposed a deterioration degree measuring device including a deterioration degree calculation unit that determines a deterioration degree by comparing an output from a function generation unit that stores a relationship with a reflection absorbance difference between wavelengths.

However, when this deterioration degree diagnosing device is used to judge the deterioration of an insulating material, such as windings of an electric motor, on the surface of which irregularities similar to the thickness of the windings are formed in a predetermined cycle,
As shown in the deterioration degree characteristic diagram of FIG. 15, the deterioration degree θ of the measurement result
Was significantly changed at each measurement point, and, for example, it was found that the measurement value was significantly changed depending on the measurement point as shown in the actual measurement characteristic diagram shown in FIG. Therefore, in order to judge the deterioration by this deterioration degree diagnosing device, it is necessary to perform a large number of measurements and calculate the average value of the deterioration degree, which is not suitable for the deterioration diagnosis of an object to be measured having irregularities.

An object of the present invention is to provide a deterioration degree diagnosing device capable of diagnosing the deterioration degree of an object to be measured having an uneven surface without stopping the operation of the equipment.

[0006]

In order to achieve the above-mentioned object, the present invention guides irradiation light from a light source with an irradiation optical fiber and irradiates the surface of an object to be measured having irregularities at a predetermined cycle,
In the deterioration degree diagnosing device, which guides the reflected light from the surface of the object to be measured to the light quantity measuring section by using the light receiving optical fiber, and judges the deterioration degree based on the output of the light quantity measuring section, the output from the light quantity measuring section Calculate the reflection absorbance difference or reflection absorbance ratio between the respective wavelengths from the reflection absorption light intensity at each wavelength from the relationship between the deterioration degree of the DUT and the reflection absorbance difference between the wavelengths or the reflection absorbance ratio in advance. A deterioration degree calculator for performing a comparison calculation is provided, and the irradiation optical fiber and the light receiving optical fiber have a diameter of a light emitting and receiving range in which the irradiation light range of the irradiation optical fiber and the light receiving range of the light receiving optical fiber overlap each other. It is characterized in that D has a size that is an integral multiple of the period of the irregularities formed on the surface of the object to be measured.

[0007]

As described above, the deterioration degree diagnosing device according to the present invention calculates the reflection absorption difference or reflection absorption ratio between wavelengths from the reflection absorption light intensity at each wavelength from the output from the light quantity measuring unit, and further, in advance, the object to be measured. Degradation degree calculation part that performs comparison calculation based on the relationship between the degree of deterioration and the reflection absorbance difference between wavelengths or the reflection absorbance ratio is provided, so the degree of material degradation can be detected nondestructively without stopping the operation of the equipment in operation. be able to. In addition, the width of the light emitting / receiving area where the light receiving area of the light receiving optical fiber that receives the reflected light from the surface of the measured object and the irradiation area that is transmitted through the irradiation optical fiber and is irradiated to the surface of the measured object overlaps Since the size is set to an integral multiple of the periodic pitch of the irregularities formed on the surface of the object to be measured, even in the case of the object to be measured having irregularities, the measurement point is 1 pitch of the irregularities or an integer multiple thereof, The average measured value of the concave portion and the convex portion is obtained from each measurement point, and it is not necessary to perform a large number of measurements as in the conventional case to calculate the average value of the deterioration degree.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram of a deterioration degree diagnosing apparatus according to an embodiment of the present invention. The light sources 6 and 14 having different wavelengths are
The reference optical fiber 7 and the irradiation optical fiber 9 are connected via the switching units 3 and 4, and the reference optical fiber 7
Is connected to the light amount measuring unit 8 via the switching unit 5, and the light amount measuring unit 8 is connected to the deterioration degree calculating unit 1. On the other hand, the irradiation optical fiber 9 is the object to be measured 11 in the reflected light measuring section 10.
The light-receiving optical fiber 13 that is guided to the surface of and measures the reflected light is connected to the light amount measuring unit 8 via the switching unit 5. The deterioration degree calculation unit 1 automatically transmits a signal to the switching control unit 2 in accordance with the measurement procedure, and controls switching of the switching units 3 to 5.

First, when measuring the amount of reference light for each wavelength, the deterioration degree calculation unit 1 switches the switching units 4 and 5 from the connection shown by the solid line in the figure to the connection shown by the dotted line. The monochromatic light having the peak wavelength λ1 generated from the light source 6 is transmitted from the switching unit 3 to the switching unit 4, and further from the reference optical fiber 7 to the switching unit 5 to the light amount measuring unit 8. The light amount measuring unit 8 measures the reference light amount I1 of the monochromatic light having the peak wavelength λ1 from the light source 6 and outputs it to the deterioration degree calculating unit 1.
The deterioration degree calculation unit 1 stores the reference light amount I1 of the light source 6. Next, the deterioration degree calculation unit 1 switches the switching units 3 to 5 from the connection shown by the solid line to the connection shown by the dotted line, and the peak wavelength λ of the light source 14 different from the peak wavelength λ1 of the light source 6 is shown.
The same operation is performed using two monochromatic lights, and the reference light amount 12 of the light source 14 is stored in the deterioration degree calculation unit 1.

Next, when measuring the amount of reflected light on the surface of the insulator, which is the object to be measured 11, the deterioration degree calculation unit 1 uses the switching unit 4.
And the switching unit 5 is switched to the connection shown by the solid line in the figure.
Therefore, the monochromatic light having the peak wavelength λ1 from the light source 6 is transmitted through the irradiation optical fiber 9 through the switching units 3 and 4, and is irradiated onto the surface of the DUT 11 in the reflected light measuring unit 10. FIG.
FIG. 3 is a partially cutaway perspective view showing the vicinity of the reflected light measuring unit 10 in an enlarged manner. The reflected light measuring unit 10 has a structure for blocking external stray light and is transmitted from the irradiation optical fiber 9 to be measured. The reflected light 12 applied to the surface of the object 11 is received by the light receiving optical fiber 13, and the transmitted light is sent to the light amount measuring unit 8 via the switching unit 5 in FIG. 1 to measure the reflected light amount I1 ′. It is output to the deterioration degree calculation unit 1. At this time, the deterioration degree calculation unit 1 calculates and stores the reflectance Rλ1 at the peak wavelength λ1 by the following mathematical expression (1). Rλ1 = 100 × I1 ′ / I1 (1) After that, the switching unit 3 is switched from the connection shown by the solid line to the connection shown by the dotted line, and the same operation is performed using the monochromatic light of the peak wavelength λ2 generated from the light source 14 in the same manner. Then, the deterioration degree calculation unit 1 calculates the peak wavelength λ2 by the following mathematical expression (2).
The reflectance Rλ2 at is calculated and stored. Rλ2 = 100 × I2 ′ / I2 (2) In this way, the reflectances at the peak wavelengths λ1 and λ2 are obtained, and in the deterioration degree calculation unit 1, the reflection absorbance difference ΔAλ1λ2 between the peak wavelengths λ1 and λ2. Is obtained by the following equation (3). ΔAλ1λ2 = Aλ1−Aλ2 (3) Further, the function generation unit 15 stores in advance a reflection absorbance difference ΔAλ corresponding to the deterioration degree of the insulator as shown in the characteristic diagram of FIG. 4 as a master curve. This is output to the deterioration degree calculation unit 1, and the deterioration degree calculation unit 1 determines the deterioration degree θ from the actually measured reflection / absorption difference ΔAλ1λ2, and the result is output to the outside as a measurement result.

Generally, the change in the reflection absorbance spectrum due to the heat deterioration of the organic material is represented by the characteristic curve shown in FIG. 2, and the reflection absorbance shows a remarkable increase on the short wavelength side in the visible region with the deterioration, and the light quantity measurement Due to the limitation on the measurement range of the part 8, it is substantially difficult to continue to measure the reflection absorbance of the material used until the end of the life of the device in the wavelength region of less than 660 nm. This increase in reflection absorbance on the short wavelength side is mainly due to an increase in electron transition absorption loss due to the thermal oxidation deterioration reaction of the material. Further, as the degree of deterioration increases, the reflection absorbance Aλ increases toward the shorter wavelength side, so the reflection absorbance difference ΔAλ between any two wavelengths also increases. Where λ1 <
Assuming that λ2, the reflection absorbance difference ΔA between the peak wavelength λ1 (nm) and the peak wavelength λ2 (nm) in FIG. 2 has a relationship of α1>α2> α3 in order from the material with the largest deterioration degree.

FIG. 5 shows a reflection absorbance spectrum measured on an insulator surface having no surface contamination and a reflection absorbance spectrum measured on an insulator surface having the same degree of deterioration and surface contamination. If the reflection absorbance difference ΔAλ between the peak wavelengths λ1 and λ2 is Δα when there is no surface fouling, and Δα ′ when there is surface fouling, then Δα≈Δ regardless of the presence or absence of fouling if the insulating material has the same degree of deterioration.
α '. Although the surface stain changes the absolute intensity of the reflected light, it generally has little wavelength dependence, and may be considered to be constant regardless of the wavelength particularly in the wavelength region described later. The same applies to measurements on the surface of an insulating material having irregularities. In this way, if the reflection absorbance difference ΔAλ between two arbitrary wavelengths is used, the degree of deterioration can be measured with almost no influence of stains and the shape of the surface of the DUT 11.

Further, as described in JP-A-3-226651, the deterioration degree is generally represented by a conversion time θ. By representing the conversion time θ, even insulating materials having various heat histories have the same degree of deterioration if the conversion times θ are equal, and the conversion time θ (Hr) is shown in FIG.
It is defined by the mathematical expression (4) shown in FIG. In the equation, ΔE is the apparent activation energy (J / mol) of thermal deterioration, R is the gas constant (J / K / mol), T is the absolute temperature of thermal deterioration (K), and t is the deterioration time (Hr). Is. The ΔE of the resin or oil forming the insulator can be easily converted by plotting the change in the reflection absorbance difference ΔAλ1λ2 with respect to several kinds of deterioration temperatures by Arrhenius plotting. Furthermore, if the conversion time at the life point of the equipment using resin or oil, etc., which is obtained in advance, is θ0, the difference Δθ from the conversion time θ obtained from the actual measurement becomes the conversion time corresponding to the remaining life, and the deterioration degree It will be a measure of judgment. That is, the remaining life Δθ (Hr)
Is represented by Equation (5) shown in FIG. 20, and this Equation (5)
Thus, if the operating temperature condition of the device after the time t is determined, the remaining life time Δt (= t0-t) can be obtained.

FIG. 9 shows a perspective view of the end surface of the optical fiber. Irregularities similar to the thickness of the winding 19 are generated at a predetermined cycle on the winding surface of the electric motor.
Of the irradiation area 9 that transmits the light and irradiates the surface of the DUT 11
a and the width D of the light emitting / receiving area 12a where the light receiving area 13a of the light receiving optical fiber 13 for receiving the reflected light 12 from the surface of the object to be measured 11 overlaps, the periodic pitch P of the unevenness due to the thickness of the winding 19 It has an integer multiple of. Therefore, with respect to the fluctuation of the deterioration degree due to the unevenness close to the thickness of the winding wire 19 on the surface of the DUT 11, the average reflected light amount can be always measured as shown in the characteristic diagram of FIG. . The width D of the light emitting / receiving area 12a shown in FIG. 9 is set to be an integer multiple of the periodic pitch P of the irregularities formed by the winding 19, for example, when the periodic pitch P of the irregularities formed by the winding 19 is 1.4 mm. When the distance to the surface of the DUT 11 is adjusted so that the width D of the light projecting / receiving area 12a is 2.8 mm by using the irradiation optical fiber 9 and the light receiving optical fiber 13 of 1.3 mm, The width D of 12a is twice the periodic pitch P of the irregularities formed by the windings 19. FIG. 17 shows a deterioration degree measurement characteristic diagram at this time, and an average reflected light amount can be measured. This becomes clearer by comparing with the case where the irradiation optical fiber 9 and the reception optical fiber 13 are configured as shown in FIG. That is, FIG. 15 shows an irradiation region in which the surface of the DUT 11 is irradiated by being transmitted through the irradiation optical fiber 9 and a light receiving region of the light receiving optical fiber 13 that receives the reflected light 12 from the surface of the DUT 11. The width D of the overlapping light emitting / receiving area 12a is determined irrespective of the periodic pitch P of the unevenness due to the thickness of the winding 19.
While the periodic pitch P is 1.4 mm, the diameter D of the light emitting / receiving range 12a where the irradiation light range of the irradiation optical fiber 9 and the light reception range of the light receiving optical fiber 13 overlap is set to 1.1 mm. There is. Unevenness is generated on the winding surface of the electric motor at a cycle similar to the thickness of the winding 19, and the recessed portion has a lesser cooling effect by the wind, so the deterioration degree is larger than that of the protruding portion. Since the diameter D of the light emitting / receiving range 12a in which the irradiation light range of the irradiation optical fiber 9 and the light reception range of the light receiving optical fiber 13 overlap is smaller than the period P of the unevenness due to the winding 19, As shown in the deterioration degree characteristic diagram, the deterioration degree θ of the measurement result greatly changes at each measurement point, unlike the case of FIG. The measured characteristic diagram is shown in Figure 1.
As shown in FIG. 6, the measured value greatly changes depending on the measuring point. Therefore, it is necessary to perform a large number of measurements to calculate the average value of the deterioration degree.

The light emitting / receiving area 12a in which the irradiation area 9a irradiated from the irradiation optical fiber 9 and the light receiving area 13a of the light receiving optical fiber 13 for receiving the reflected light 12 are overlapped with each other.
The various light emitting and receiving regions can be obtained depending on the shape and arrangement of the fiber used. 10, FIG. 11, FIG. 12 and FIG.
3 shows that the light emitting / receiving area 12a having a required form is obtained by different combinations of the irradiation optical fiber 9 and the light receiving optical fiber 13.

FIG. 6 shows a block diagram of a deterioration degree diagnosing device according to another embodiment of the present invention. In the previous embodiment, the monochromatic light having the peak wavelength λ1 generated from the light source 6 and the peak generated from the light source 14 are shown. While the monochromatic light having the wavelength λ2 is switched and used, in the present embodiment, the peak wavelengths λ1 and λ
The light sources 6, 14 and 18 for monochromatic light of 2, λ3 are commonly connected. The monochromatic light sources 6, 14, and 18 having the peak wavelengths λ1, λ2, and λ3 are coupled by the optical coupler 16 and connected to the switching unit 4 as one optical fiber. Since it does not have interference, it operates well, and the reflected light 12 from the surface of the object to be measured 11 is processed by a filter corresponding to each wavelength incorporated in the light quantity measuring unit 8 in a time-division manner to operate each wavelength. The light quantity for is measured instantly. The deterioration degree calculation unit 1 calculates and stores the reflectances Rλ1 to Rλ3 at the peak wavelengths λ1 to λ3. From the reflectances Rλ1 to Rλ3, the deterioration degree calculation unit 1 calculates data between arbitrary two wavelengths among the wavelengths. The reflection absorbance difference ΔAλλ ′ of is calculated from the following equation (6).

ΔAλλ ′ = Aλ−Aλ ′ (6) Further, in the function generator 15, the difference in reflection absorbance corresponding to the degree of deterioration of the insulator as shown in the characteristic diagram of FIG. The master curve is stored in advance as a master curve as shown in FIG. 1 and is output to the deterioration degree calculation unit 1, and the deterioration degree calculation unit 1 determines the deterioration degree from the stored function value and the actually measured reflection absorbance difference ΔAλλ ′. Is output as a measurement result, and the same effect as that of the previous embodiment can be obtained.

FIG. 7 is a block diagram of a deterioration degree diagnosing device according to a further different embodiment of the present invention, in which a white light source 17 such as a halogen lamp is used as a light source, and a light quantity measuring section 8 is used.
Is equipped with a spectroscope consisting of an interference filter.
The amount of light of each wavelength of 0 to 900 nm is instantly measured. Similar to the embodiment of FIG. 1, first, 500 to 90
The reference light amount for each wavelength of 0 nm is measured, and the reflected light amount of the reflected light 12 from the surface of the DUT surface 11 is measured by the light amount measuring unit 8 and the deterioration degree calculating unit 1
The result is output to. In the deterioration degree calculation unit 1, a wavelength of 500
The reflectance R500 to R900 at 900 nm is continuously calculated and stored, and the reflectance absorbance difference ΔAλλ ′ between any two wavelengths is calculated from the above equation (6) from the reflectance R500 to R900 at the wavelength 500 to 900 nm, and the function is calculated. 4 is stored in the generation unit 15 in advance and the deterioration degree calculation unit is calculated from the function value by the master curve as shown in FIG. 4 of the reflection absorption difference corresponding to the deterioration degree of the insulator and the actually measured reflection absorption difference ΔAλλ ′. The degree of deterioration is judged at 1 and output as a judgment result to the outside.

In the above-mentioned embodiment, the difference in reflection absorbance between wavelengths is calculated from the reflection absorbance Aλ at each wavelength based on the output from the light quantity measuring unit 8. However, from the reflection absorption absorbance Aλ shown in FIG. The reflection absorbance ratio is obtained, and the function generation unit 15 shown in FIG. 1 stores in advance the reflection absorbance ratio AR ′ corresponding to the degree of deterioration of the insulator as the master curve as shown in the characteristic diagram of FIG. Even if it is output to the deterioration degree calculation unit 1 and the deterioration degree calculation unit 1 determines the deterioration degree θ from the actually measured reflection / absorbance ratio and is output to the outside as a measurement result,
It is possible to obtain almost the same effect.

[0020]

As described above, the deterioration degree diagnosing device according to the present invention calculates the reflection absorption difference or the reflection absorption ratio between wavelengths from the reflection absorption light intensity at each wavelength from the output from the light quantity measuring unit, and further, in advance. Irradiation that irradiates the surface of the object to be measured by transmitting an optical fiber for irradiation and providing a deterioration degree calculation unit that performs comparison calculation from the relationship between the degree of deterioration of the object to be measured and the above-mentioned reflection absorbance difference between wavelengths or the reflection absorbance ratio. Since the width of the area and the light emitting / receiving area where the light receiving area of the light receiving optical fiber for receiving the reflected light from the surface of the object to be measured overlaps is set to be a positive multiple of the periodic pitch of the unevenness of the object to be measured, It is possible to nondestructively measure an average degree of deterioration that does not differ depending on the measurement point even when the object under measurement has irregularities on the surface without stopping the operation of the device in actual operation.

[Brief description of drawings]

FIG. 1 is a block diagram of a deterioration degree diagnosing apparatus according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram of a reflection absorption spectrum of an insulator.

3 is an enlarged perspective view showing a reflected light measuring unit of the deterioration degree diagnosing device shown in FIG. 1. FIG.

FIG. 4 is a master curve of reflection absorbance difference corresponding to the degree of deterioration of an insulator.

FIG. 5 is a characteristic diagram of a reflection absorbance spectrum.

FIG. 6 is a block diagram of a deterioration degree diagnosing device according to another embodiment of the present invention.

FIG. 7 is a block diagram of a deterioration degree diagnosing device according to another embodiment of the present invention.

8 is a deterioration degree characteristic diagram of the deterioration degree diagnostic device shown in FIG. 1. FIG.

9 is a perspective view of an optical fiber end face portion of the deterioration degree diagnosing device shown in FIG. 1. FIG.

FIG. 10 is a combination diagram of an irradiation optical fiber and a light receiving optical fiber of a deterioration degree diagnosing device according to another embodiment of the present invention.

FIG. 11 is a combination diagram of an irradiation optical fiber and a light receiving optical fiber of a deterioration degree diagnosing device according to still another embodiment of the present invention.

FIG. 12 is a combination diagram of an irradiation optical fiber and a reception optical fiber of a deterioration degree diagnosing device according to still another embodiment of the present invention.

FIG. 13 is a combination diagram of an irradiation optical fiber and a light receiving optical fiber of a deterioration degree diagnosing device according to still another embodiment of the present invention.

FIG. 14 is a deterioration degree characteristic diagram of a conventional deterioration degree diagnostic device.

FIG. 15 is a perspective view showing an end face portion of an optical fiber of a conventional deterioration degree diagnosing device.

FIG. 16 is a characteristic diagram of actual measurement by a conventional deterioration degree diagnostic device.

FIG. 17 is an actual measurement characteristic diagram of the deterioration degree diagnostic device shown in FIG. 1.

FIG. 18 is a master curve of a reflection absorbance ratio corresponding to the degree of deterioration of an insulator.

FIG. 19 is a mathematical expression for obtaining a converted time θ.

FIG. 20 is a mathematical expression for obtaining the remaining life Δθ.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Degradation degree calculation part 6 Light source 8 Light intensity measuring part 9 Irradiation optical fiber 10 Light intensity measuring part 11 DUT 12 Reflected light 12a Light emitting / receiving area 13 Light receiving optical fiber 14 Light source

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Nobuo Yokomori 1-6-6 Kandanishikicho, Chiyoda-ku, Tokyo Within Hitachi Building System Service Co., Ltd. (72) Inventor Yoshitaka Takezawa 7-1 Omikacho, Hitachi City No. 1 Hitachi, Ltd. Hitachi Research Laboratory

Claims (2)

[Claims] 1. The irradiation light from a light source is guided by an irradiation optical fiber to irradiate the surface of an object to be measured having irregularities at a predetermined cycle, and the reflected light from the surface of the object to be measured is received using an optical fiber for receiving light. Guided to the light amount measurement unit, in the deterioration degree diagnostic device for determining the degree of deterioration based on the output of the light amount measurement unit, from the output from the light amount measurement unit from the reflection absorption light intensity at each wavelength from the reflection absorbance difference between each wavelength A deterioration degree calculation unit for performing calculation and further performing comparison calculation from the relationship between the deterioration degree of the DUT and the reflection absorbance difference between the wavelengths is provided, and the irradiation optical fiber and the light receiving optical fiber are The diameter D of the light emitting / receiving range where the light receiving range of the light receiving optical fiber and the light receiving range of the light receiving optical fiber overlap is set to an integral multiple of the cycle of the unevenness formed on the surface of the object to be measured. Characteristic material Deterioration degree diagnostic device. 2. The irradiation light from a light source is guided by an irradiation optical fiber to irradiate the surface of an object to be measured having irregularities at a predetermined cycle, and the light reflected from the surface of the object to be measured is received using an optical fiber for receiving light. Guided to the light amount measurement object, in the deterioration degree diagnostic device for determining the deterioration degree based on the output of this light amount measurement unit, from the output from the light amount measurement unit from the reflection absorption light intensity at each wavelength to the reflection absorbance ratio between the respective wavelengths Computation, further provided with a deterioration degree calculator for performing a comparative calculation from the relationship between the degree of deterioration of the object to be measured and the reflection absorption degree ratio between the wavelengths, the irradiation optical fiber and the light receiving optical fiber, The diameter D of the light emitting / receiving range in which the light receiving range of the light receiving optical fiber and the light receiving range of the illumination optical fiber overlap is set to an integral multiple of the cycle of the unevenness formed on the surface of the object to be measured. Of the material characterized by Deterioration degree diagnostic device.