JPH1151854A - Spectroscopic analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spectroscopic analyzer in which the durability and the analytical accuracy are not affected even when the analyzer is used in a dusty site. SOLUTION: The spectroscopic analyzer comprises a detecting section 3 for irradiating an object with a measuring light beam from a light source 1 and receiving the light reflected on the object or transmitted through the object, and a section A for analyzing the components of the object spectroscopically based on the spectrum of a light received at the detecting section 3. A gas is supplied, while removing dust through a dust removing means F, to the inside of a section O surrounding the light source 1 and the spectroscopic analyzing section A such that the pressure in the surrounding part P will be higher than the pressure on the outside. Furthermore, a ventilation means T discharges the inner air, the spectroscopic analyzing section A is provided with an analysis start command from a command means 11 and the detecting section 3 is disposed on the outside of the surrounding part P.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detection unit configured to irradiate a measurement light beam from a light source unit to an object to be analyzed and to receive reflected light or transmitted light from the object to be analyzed. Obtain the spectrum of the light received by the detector,
The present invention relates to a spectroscopic analyzer provided with a spectroscopic analysis unit for analyzing a component contained in an analyte based on an obtained spectroscopic spectrum.

[0002]

2. Description of the Related Art In such a spectroscopic analyzer, conventionally,
In particular, no dust protection measures were taken.

[0003]

Incidentally, in such a spectroscopic analyzer, when dust enters the light source section or the spectroscopic analysis section, the spectroscopic spectrum is changed by the dust and the analysis accuracy may be reduced. Since it is composed of precision parts, mainly microcomputers, it is necessary to prevent exposure to a dusty atmosphere. Therefore, the conventional spectrometer needs to be used in a place with little dust,
Since there is a restriction on the place of use, the usability is poor and improvement has been desired.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a spectroscopic analyzer which can be used without being affected by durability and analysis accuracy even in a dusty place. It is in.

[0005]

According to the first aspect of the present invention, the inside of the enclosure surrounding the light source section and the spectroscopic analysis section has a higher pressure than the outside when the gas removed by the dust removal means is higher than the outside. As a result, the atmosphere is prevented from entering the inside. Thereby, the atmosphere around the light source unit and the spectroscopic analysis unit can be maintained in an atmosphere with less dust. Further, since the detection unit and the command unit are provided outside the enclosure, the analysis target is arranged at a predetermined position for analysis with respect to the detection unit, or the command unit instructs the start of analysis. The operability of the work to be performed does not decrease. Therefore, it has become possible to provide a spectroscopic analyzer which can be used without being affected by durability and analysis accuracy even in a place where there is a lot of dust and the operability is not deteriorated.

According to the second aspect of the present invention, the gas flowing through the cooling fan originally provided for cooling the light source is discharged to the outside of the enclosure. An air fan is provided to supply gas into the enclosure in a state where dust is removed by the dust removing means, and a supply amount of gas per unit time by the supply fan is equal to a supply of gas per unit time by the cooling fan. It is configured to be larger than the amount, and the inside of the enclosure is filled with the gas removed by the dust removing means at a pressure higher than the outside. Further, a part of the gas supplied by the air supply fan is guided to the airflow by the cooling fan and flows through the light source unit, so that the gas flow rate of the gas flowing through the light source unit increases. Therefore, it is possible to achieve the effect that the cooling capacity of the light source unit is further improved while configuring the ventilation unit using the cooling fan originally provided.

According to the third aspect of the present invention, the display means for displaying the analysis result is provided inside the enclosure, but from outside the enclosure through a transparent portion provided in the enclosure. The display information on the display means can be visually recognized. Therefore, it is possible to prevent the durability of the display means made of precision parts from being affected by dust and to prevent the operability for visually recognizing the display information of the display means from deteriorating.

According to a fourth aspect of the present invention, the spectroscopic analysis unit is configured to analyze components contained in the fruits and vegetables with the fruits and vegetables as an analysis target. That is, such a spectroscopic analyzer may be used for component analysis of fruits and vegetables, for example, in a group of producers of fruits and vegetables, etc., it may be used for sorting of fruits and vegetables, but dust is not included in the fruits and vegetables. Many are attached. Therefore, the present invention
When applied to a spectroscopic analyzer that uses fruits and vegetables as the analysis target,
It is suitable.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the spectroscopic analyzer irradiates a measurement light beam from a main body unit M, a control unit C, and a light source unit 1 to an analysis target and receives reflected light from the analysis target. The light emitting / receiving adapter 3 as a configured detecting unit is separately provided, and a rack R on which the main unit M and the control unit C are mounted is provided.
FIG. 1A shows a state in which an enclosure P described later is removed, and FIG. 1B shows a state in which the enclosure P is attached.

As shown in FIG. 2, the main body M includes a spectroscopic section 4 for obtaining a spectroscopic spectrum of light received by the light emitting and receiving adapter 3, a light source section 1, and the light source section 1 in a casing 9.
The cooling fan 10 is provided so that the cooling air can flow therethrough. The cooling fan 10 is provided with its discharge portion aligned with the exhaust opening 9 a of the casing 9. The casing 9 has a slit 9b for ventilation.

As shown in FIG. 1, the control unit C includes a spectroscopic unit 4
A processing unit 5 for analyzing components contained in the analysis object based on the spectrum obtained in the step 5, a liquid crystal display 7 as a display means for displaying and outputting the analysis result of the processing unit 5, and setting analysis conditions and the like. Keyboard 8 to be integrated into an integrated unit. That is, the spectral unit 4
The processing unit 5 constitutes a spectral analysis unit A that obtains a spectral spectrum of light received by the light emitting / receiving adapter 3 and analyzes components contained in the analysis target based on the obtained spectral spectrum.

As shown in FIGS. 1, 3 and 4, the light emitting / receiving adapter 3 is provided with a start switch 11 as command means for commanding the processing section 5 to start analysis.
Then, the main body M and the separate light emitting and receiving adapter 3 are guided to the measuring light emitting and receiving adapter 3 from the light source 1 and the light received by the light emitting and receiving adapter 3 is split into the spectroscopic part 4.
Is connected by a measurement probe 2 leading to the above.

As shown in FIGS. 1 and 2, an enclosure P surrounding the main body M and the control section C, and a filter 15 as a dust removing means F so that the pressure inside the enclosure P becomes higher than the outside. Is provided, a ventilation means T for supplying outside air to the inside and discharging the inside air is provided, and the light emitting / receiving adapter 3 provided with the start switch 11 is provided outside the enclosure P.

The rack portion R is formed by integrally assembling a pair of vertical frame members 12 and two shelf members 13 so as to be movable by a caster 14 having fixing means (not shown). It is composed. Then, it is configured to be moved to a predetermined place by the casters 14 and fixedly arranged at the place by the fixing means.

The plate member 16 is provided so as to be fitted into a rectangular frame portion formed by the upper and lower two shelf members 13 and the vertical frame member 12. The plate-like material 16 has a ventilation opening 16a,
A hole 16b for inserting the measuring probe 2 connected to the light emitting / receiving adapter 3 is formed. Air supply fan 17
Is fitted into the ventilation opening 16a, and
The filter 15 is provided so as to be supported by the plate-like material 16 in a state where the filter 15 is positioned on the intake side of the air supply fan 17.

The measurement probe 2 is connected to the hole 16
b, and the main body M
And the light emitting / receiving adapter 3 located on the opposite side of the main body portion M with respect to the plate-like material 16.

A transparent and flexible sheet material (for example,
A rectangular parallelepiped bag-like member 18 made of vinyl) is provided over the rack portion R in a state where the bag-like member 18 is supported by the pair of vertical frames 12, and the opening edge of the bag-like member 18 is set to the peripheral edge of the lower shelf member 13. These are joined together with a band-shaped member 19 and a screw 20. In the bag-like member 18, an air supply opening 18 a is formed in a portion overlapping the plate-shaped material 16, and an exhaust opening 18 b is formed in a portion overlapping the exhaust opening 9 a of the casing 9 of the main body M. is there. Further, the bag-like member 18 has
A slit is provided, and a fastener 18c is provided to open and close the slit. The opening edge of the air supply opening 18a of the bag-like member 18 is
, The opening edge of the exhaust opening 18 b of the bag-like member 18 is joined to the casing 9 of the main body M by the band-like member 19 and the screw 20.

Accordingly, the bag-like member 18 and the lower shelf member 13
Thus, the enclosure P is formed. In addition, fastener 18
Since the slit of the bag-like member 18 can be opened and closed by the operation of c, it is possible to inspect the inside, operate the keyboard 8 and the like with the enclosure P attached. Further, a part of the enclosure P is formed of a transparent bag-shaped member 18 so that display information on the liquid crystal display 7 can be visually recognized in a state where the enclosure P is attached.

The outside air passes through the filter 15 and is dust-removed by the air supply fan 17 and supplied to the inside of the enclosure P. The cooling fan 10 allows the air in the enclosure P to pass through the slit 9 b of the casing 9. Is introduced into the casing 9, flows through the casing 9, and is discharged to the outside through the exhaust opening 18 b of the bag-shaped member 18. The air supply amount of the air supply fan 17 per unit time is determined by the cooling fan 1.
The air exhaust amount per unit time is set to be larger than zero, and the air supply fan 17 and the cooling fan 10 constitute the ventilation means T.

Hereinafter, based on FIG. 3, the light source unit 1, the measuring probe 2, the light emitting and receiving adapter 3, the spectral unit 4, and the processing unit 5 will be described.
Is added. The light source unit 1 includes a tungsten-halogen lamp 1a that emits infrared light as a measurement light beam.
And a lens 1b for shaping the measuring light beam from the tungsten-halogen lamp 1a into a parallel light beam. The light source unit 1 is provided with a shutter unit 6 that can be switched between an irradiation state in which a measurement light beam from the light source unit 1 irradiates the analysis target S and a non-irradiation state in which irradiation is not performed. The shutter portion 6 is a shutter plate movably supported between the lens 1b and the incident end of the measurement light beam on the measurement probe 2 in a light-shielded state for shielding the measurement light beam and a non-light-shielded state for not shielding the measurement light beam. 6a and an electromagnetic solenoid 6b for moving and driving the shutter plate 6a. By switching the shutter unit 6 to the non-light-shielding state, the irradiation state is set, and by switching to the light-shielding state, the non-irradiation state is set.

The measuring probe 2 includes an irradiation optical fiber 2.
a and a light receiving optical fiber 2b.
The irradiating optical fiber 2a and the receiving optical fiber 2b are formed in a ring shape except for the incident end side of the measuring light beam in the irradiating optical fiber 2a and the emitting end side of the diffuse reflection light in the receiving optical fiber 2b. The light receiving optical fiber 2b is located coaxially inside the irradiation optical fiber 2a, and the coaxial end face has an annular tip end face of the irradiation optical fiber 2a and the light receiving optical fiber inside it. The circular tip surface of 2b is flush.

As shown in FIG.
Is connected to the tip of the measurement probe 2. The light emitting and receiving adapter 3 includes an outer cylinder 3a, an inner cylinder 3b coaxially located inside the outer cylinder 3a at a distance from the outer cylinder 3a, an outer cylinder 3a and the inner cylinder. A connecting member 3c for connecting the connecting cylinder 3b to the mounting cylinder 3b, a mounting cylinder 3d externally fixed to one end of the outer cylinder 3a, and a screw 3 screwed into the mounting cylinder 3d.
e. Then, the light emitting / receiving adapter 3 is connected to the tip of the measuring probe 2 by externally fitting the mounting cylinder 3d to the measuring probe 2 and tightening the screw 3e. Reference numeral 3f in the drawing denotes a probe casing that houses the outer cylindrical body 3a and the inner cylindrical body 3b assembled as described above with their distal ends exposed.

The inner cylindrical body 3b is formed in a truncated conical shape in which the inner diameter and the outer diameter of the cylinder become smaller as it approaches the fiber connection portion on the base end side, and the thickness of the peripheral wall becomes smaller as it approaches the probe 2 for measurement. It is formed so that it becomes. Further, the inner cylindrical body 3b has an inner diameter substantially the same as the diameter of the circular distal end surface of the light receiving optical fiber 2b at the fiber connection portion on the base end side, and the thickness of the peripheral wall is equal to the distal end of the light receiving optical fiber 2b. The distance between the surface and the distal end surface of the irradiation optical fiber 2a is substantially the same. The inner and outer peripheral surfaces of the inner cylindrical body 3b are finished to mirror surfaces capable of reflecting light. The outer cylinder 3a is formed in a truncated conical shape in which the inner diameter and the outer diameter of the cylinder become smaller as they approach the fiber connection portion on the base end side. Further, the outer cylindrical body 3a has an inner diameter substantially the same as the outer diameter of the annular distal end surface of the irradiation optical fiber 2a at the fiber connection portion on the base end side. The inner peripheral surface of the outer cylinder 3a is finished to a mirror surface capable of reflecting light.

That is, the shape of the opening of the fiber connection portion on the proximal end side of the inner cylindrical body 3b becomes substantially the same as the shape of the distal end surface of the optical fiber 2b for light reception, and the shape of the outer end of the inner cylindrical body 3b is substantially the same as that of the outer end. The shape of the annular opening formed by the base end of the cylindrical body 3a is substantially the same as the shape of the annular distal end surface of the irradiation optical fiber 2a. In addition, light emitting and receiving adapter 3
Is connected to the distal end of the measurement probe 2, the opening of the inner cylindrical body 3b is located in a state facing the distal end surface of the light-receiving optical fiber 2b, and is formed in the inner cylindrical body 3b and the outer cylindrical body 3a. The opening is located so as to face the distal end surface of the light receiving optical fiber 2a. And the inner cylinder 3b
An annular opening formed by the distal end of the outer cylindrical body 3a and the distal end of the outer cylindrical body 3a function as the irradiating section O, and the distal opening of the inner cylindrical body 3b functions as the light receiving section I.

Therefore, as described below, the light emitting / receiving adapter 3
A measurement light beam is applied to the analysis target S abutted on the tip of the sample, and diffuse reflection light from the analysis target S is received. That is, the shutter unit 6 is switched to the non-light-shielded state. Then, the measuring light beam from the light source unit 1 guided by the irradiation optical fiber 2a enters the space between the inner cylinder 3b and the outer cylinder 3a from the distal end surface of the irradiation optical fiber 2a, The light passes through the space and is emitted toward the analysis target S from an annular irradiation unit O formed by the tip of the inner cylinder 3b and the tip of the outer cylinder 3a. Then, the diffusely reflected light from the analysis target S enters the inner cylinder 3b from the light receiving section I functioning at the opening at the tip end of the inner cylinder 3b,
b, the light exits toward the distal end surface of the light receiving optical fiber 2b, and is guided to the light splitting unit 4 by the light receiving optical fiber 2b.

As described above, by connecting the light emitting / receiving adapter 3 to the tip of the measuring probe 2, the object S
Since the distance between the measurement light irradiation unit O and the light receiving unit I of the reflected light from the analysis target S can be widened, the diffuse reflection light from the analysis target S can be received. .

The spectroscopic unit 4 includes a reflecting mirror 4a for reflecting the diffusely reflected light guided by the light receiving optical fiber 2b, and a reflecting mirror 4a.
A concave diffraction grating 4b that spectrally reflects the diffuse reflection light reflected by the optical element, and an array-type light receiving element 4c that detects the light flux intensity for each wavelength spectrally reflected by the concave diffraction grating 4b. The array type light receiving element 4c includes a concave diffraction grating 4b.
At the same time, the light is simultaneously received for each wavelength and converted into a signal for each wavelength and output. The reflecting mirror 4a, the concave diffraction grating 4b, and the array type light receiving element 4c
It is arranged in an aluminum dark box 4d that blocks light from the outside, and diffused and reflected light guided by the light receiving optical fiber 2b is guided into the dark box 4d through an incident hole 4e formed in the dark box 4d. It is composed.

The processing section 5 will be described. Processing unit 5
Is configured using a microcomputer. When a start command is given by a start switch 11, the shutter unit 6 is switched to a non-light-shielded state, an output signal from the array type light receiving element 4c is processed, and the The spectrum and the second derivative in the wavelength region of the absorbance spectrum are obtained, and the components included in the analyte S are analyzed based on the second derivative, and the analysis result is output to the liquid crystal display 7. At the same time, the shutter section 6 is switched to a light-shielded state.

The processing unit 5 analyzes the object S based on the multiple regression analysis based on the following arithmetic expression (hereinafter referred to as a calibration expression).
The amount of each component contained in is calculated. Y = K ₀ + K ₁ × A (λ ₁ ) + K ₂ × A (λ ₂ ) + K ₃
× A (λ ₃ ) where Y: component amount K ₀ , K ₁ , K ₂ , K ₃ …; coefficient A (λ ₁ ), A (λ ₂ ), A (λ ₃ ) ……; Wavelength λ
Derivative of absorbance spectrum at

In the processing unit 5, a specific calibration formula is set for each component for each type of the analyte. That is, in the above calibration formula, specific coefficients K ₀ , K ₁ , K ₂ , K _3, ...
Wavelengths λ ₁ , λ ₂ , λ ₃ ... Are set.

Then, the processing unit 5 sets the above-mentioned calibration formula so as to correspond to the type set on the keyboard 8, and obtains the component amounts based on the set calibration formula.

[Another Embodiment] Next, another embodiment will be described. (A) The specific configuration of the enclosure P may be various configurations other than the configuration exemplified in the above embodiment. For example, instead of the bag-like member 18 in the above embodiment,
The periphery of the rack R may be surrounded by a plate made of plastic or metal. Alternatively, the main body M and the control unit C may be provided directly inside a box-shaped body that functions as the enclosure P without mounting the main body M and the control unit C on the rack R.

(B) As the specific configuration of the ventilation means T, various configurations other than the configuration exemplified in the above embodiment are possible. For example, in the above-described embodiment, an example has been described in which the air flowing through the cooling fan 10 is configured to be discharged to the outside of the enclosure P, and the ventilation unit F is configured using the cooling fan 10. Alternatively, the air flowing through the cooling fan 10 may be configured to be discharged into the enclosure P, and the ventilation unit F may include only the air supply fan 17. In this case, an air vent for venting air may be formed in the enclosure P.

Alternatively, a differential pressure damper may be provided in the enclosure P so that the pressure in the enclosure P is kept constant.

(C) As the specific structure of the dust removing means F, various structures other than the filter 15 exemplified in the above embodiment are possible. For example, as shown in FIG. 5, the upper part of the water surface part is constituted by a water tank 21 closed at an interval from the water surface part, and the air is supplied by the air supply fan 17 so that the water flows through the water in the water tank 21. After removing dust in the air with water,
You may make it supply in the surrounding part P. In this case, if the water in the water tank 21 is adjusted to a predetermined temperature, the fluctuation in the temperature in the enclosure P can be reduced.
Analysis accuracy can be improved. Further, since the temperature in the enclosure P can be lowered, the durability of the device can be improved.

(D) As the specific configuration of the command means, various configurations are possible other than the start switch 11 exemplified in the above embodiment. For example, a sensor that detects the presence or absence of the analysis target S may be configured. In this case, the operator does not need to perform an operation for issuing a command to start analysis and a command to end analysis, so that operability can be further improved.

(E) Various configurations are possible for the specific configuration of the detection unit other than the light emitting and receiving adapter 3 exemplified in the above embodiment. For example, it may be configured to receive the transmitted light transmitted through the analysis target S.

(F) In the above embodiment, the case where the command means is attached to the detection unit has been exemplified, but the command means may be provided separately from the detection unit.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the overall configuration of a spectroscopic analyzer.

FIG. 2 is a cross-sectional view of the spectroscopic analyzer.

FIG. 3 is a block diagram of a spectroscopic analyzer.

FIG. 4 is a cross-sectional view along the optical path of a measuring light beam in the light emitting and receiving adapter.

FIG. 5 is a block diagram illustrating a ventilation unit and a dust removal unit according to another embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source part 3 Detecting part 7 Display means 11 Command means 10 Cooling fan 17 Air supply fan A Spectroscopic analysis part F Dust removal means P Enclosure part T Ventilation means

Claims (4)

[Claims] 1. A detection unit configured to irradiate a measurement light beam from a light source unit to an object to be analyzed and to receive reflected light or transmitted light from the object to be analyzed, and the detection unit receives the light. A spectral analysis apparatus provided with a spectral analysis unit that obtains a light spectrum and analyzes components included in an analyte based on the obtained spectrum, wherein the light source unit and the spectrum analysis unit are provided. So that the pressure inside the enclosure and the pressure inside the enclosure is higher than the outside
A gas supply unit for supplying gas to the inside in a state where dust is removed by the dust removal unit, and a ventilation unit for discharging the inside gas are provided, a command unit for instructing the spectroscopic analysis unit to start analysis,
And a spectroscopic analyzer in which the detection unit is provided outside the enclosure. 2. An air supply fan for supplying gas into the enclosure in a state where dust is removed by the dust removing means is provided, and a gas flowing through the cooling fan that allows a cooling gas to flow through the light source unit is provided. It is configured to be discharged to the outside of the enclosure, and the supply amount of gas per unit time by the air supply fan is configured to be larger than the discharge amount of gas per unit time by the cooling fan. The ventilation means,
2. The spectroscopic analyzer according to claim 1, comprising the air supply fan and the cooling fan. 3. A display means for displaying an analysis result of the spectroscopic analysis unit is provided inside the enclosure, and the display unit is configured to display information on the display unit from outside the enclosure. 3. The spectroscopic analyzer according to claim 1, further comprising a transparent portion. 4. The spectroscopic analyzer according to claim 1, wherein the spectroscopic analyzer is configured to analyze a component contained in the fruits and vegetables with the fruits and vegetables as an analysis target.