Patent Description:
In related art, a spectroscope that disperses measurement light to obtain an optical spectrum on a wavelength basis is known. Such a spectroscope is used in various applications such as an application of determining the material of plastic for recycling resources.

For example, a spectroscope described in <CIT> includes a rotatable diffraction grating and rotatable reflecting means. The spectroscope corrects a deviation of the optical-axis in a direction intersecting with the optical-axis, the deviation which is generated when the diffraction grating is rotated to increase diffraction efficiency, by rotation of the reflecting means.

However, the spectroscope may vary in accordance with a dimensional tolerance or an assembly tolerance of a component. The above-described spectroscope corrects a deviation of the optical-axis in the direction intersecting with the optical-axis; however does not correct a deviation of the focus position or the like of emission light emitted from the spectroscope in the optical-axis direction.

<CIT> discloses a spectroscope with a diffraction grating for dispersing incident light and a micromechanical tiltable mirror.

<CIT> discloses a frame, a spectroscope, a spectrometry unit, and an image forming apparatus. The frame has hollow structure and includes at least four apertures including a first aperture, a second aperture, a third aperture through which light enters the frame, and a fourth aperture, a concave diffraction grating disposed at a position of the first aperture, and a movable reflector disposed at a position of the second aperture to reflect light dispersed by the concave diffraction grating and change a reflection angle of the reflected light. Through the fourth aperture of the frame, the light reflected by the movable reflector exits the frame. The spectroscope includes the frame, and the frame further includes an optical entrance disposed at a position of the third aperture, and an optical exit disposed at a position of the fourth aperture.

<CIT> discloses a spectral colorimetric apparatus for detecting a color of an image of a subject, including: an illumination optical system illuminating the subject on a detection surface; a spectral optical system including a spectral element spectrally separating the beam diffused by the subject and a light receiving element array detecting a spectral intensity distribution; and a guiding optical system for guiding a beam diffused by the subject, wherein: the detection surface is parallel to a spectral plane including a principal ray of a beam entering the spectral optical system and a principal ray of a beam spectrally separated; the principal ray of the beam enters the spectral optical system within the spectral plane obliquely to a line joining a center of the light receiving element array with a surface vertex of the spectral element; and a light receiving surface of the light receiving element array is orthogonal to the spectral plane. <CIT> discloses spectrometer optics with a beam path from a beam source to a number of electro-optical sensors without spatial resolution, the beam path comprising an entry slot, a dispersive element, and a number of exit slots arranged on a focal curve, wherein furthermore: a first actuator for changing the angle of incidence ε between the beam from the entry slot to the dispersive element and from the normal to the dispersive element; a number of second actuators for moving the exit slots tangentially with respect to the focal curve or in a peripheral direction along the focal curve and a controller which is adapted to control the first actuator and the second actuators to carry out a calibration is provided.

Embodiments of the present disclosure provide a spectroscope as defined in independent claim <NUM>.

Embodiments of the present disclosure provide an analysis system including the spectroscope; and a processor that analyzes a spectrum obtained by the spectroscope.

Embodiments for implementing the present disclosure are described below in detail referring to the drawings. Like reference signs are applied to identical or corresponding components throughout the drawings and redundant description thereof may be omitted where appropriate.

The embodiment described below is illustrative of a spectroscope for embodying the technical idea of the present disclosure, and the present disclosure is not limited to the embodiment described below. The dimensions, materials, shapes, relative arrangements, and so forth, of the components described below are not intended to limit the scope of the present disclosure thereto, and are intended to be examples unless otherwise specifically indicated. The size, positional relationship, and so forth, of members illustrated in the drawings may be exaggerated for clarity of description.

A configuration of a spectroscope <NUM> according to a first embodiment is described referring to <FIG> and <FIG>. <FIG> is a perspective view illustrating a general arrangement of the spectroscope <NUM>. <FIG> is a cross-sectional view illustrating a Rowland circle <NUM> in the spectroscope <NUM>.

As illustrated in <FIG> and <FIG>, the spectroscope <NUM> includes a light incidence section <NUM>, a concave diffraction grating <NUM>, a movable light reflector <NUM>, a light emitter <NUM>, a substrate <NUM>, and a light detector <NUM>. <FIG> also indicates a local coordinate system of each component.

The light incidence section <NUM> is an example of light incidence means that allows light Li from the outside to be incident. The light incidence section <NUM> allows the light Li from the outside to be incident on the spectroscope <NUM> through a first light passing portion <NUM>. A region of the light incidence section <NUM> other than the first light passing portion <NUM> defines a first light non-passing portion <NUM> that does not allow the light Li to pass therethrough. The first light passing portion <NUM> has, for example, a pinhole shape or a slit shape, and is provided to determine the incident position of light and to increase the wavelength resolution.

The concave diffraction grating <NUM> is an example of a diffraction grating that disperses the wavelengths of the light Li incident on the concave diffraction grating <NUM> by the light incidence section <NUM>. The concave diffraction grating <NUM> is formed on the substrate <NUM>. The concave diffraction grating <NUM> diffracts the light Li to disperse the wavelengths of the light Li, and reflects wavelength dispersed light Ld toward the movable light reflector <NUM>. Beams of light having different wavelengths included in the wavelength dispersed light Ld propagate while being converged, are incident at different positions on a reflection line <NUM> on a reflecting surface <NUM>, and are reflected by the reflecting surface <NUM>.

The material of the substrate <NUM> may be, but is not limited to, for example, a semiconductor, a glass, a metal, or a resin. The concave diffraction grating <NUM> may be directly formed on the substrate <NUM>, or may be formed on a thin film layer, for example, a resin layer, formed on the substrate <NUM>.

The movable light reflector <NUM> is an example of reflecting means having the reflecting surface <NUM> whose inclination is variable. The movable light reflector <NUM> reflects the wavelength dispersed light Ld caused by the concave diffraction grating <NUM> toward the light emitter <NUM> by the reflecting surface <NUM>.

The movable light reflector <NUM> has a swing axis <NUM>. The movable light reflector <NUM> swings around the swing axis <NUM> to change the inclination of the reflecting surface <NUM> that reflects the wavelength dispersed light Ld. Scanning with the wavelength dispersed light Ld is performed in accordance with the inclination of the reflecting surface <NUM>.

The movable light reflector <NUM> can be formed in a thin and small shape on a semiconductor substrate by, for example, a semiconductor process or a micro electro mechanical systems (MEMS) process. Since the movable light reflector <NUM> is formed on the semiconductor substrate, a driving element section for piezoelectric driving, electrostatic driving, electromagnetic driving, or the like, can be monolithically formed on the semiconductor substrate. Thus, the spectroscope <NUM> can drive the movable light reflector <NUM> without using an external driving device such as a motor, thereby attaining a further decrease in size. However, the substrate on which the movable light reflector <NUM> is formed is not limited to a semiconductor, and may be a glass, a metal, a resin, or the like.

The light emitter <NUM> is an example of light emitting means that emits, to the outside through a second light passing portion <NUM>, part of the beams of light having the different wavelengths included in the wavelength dispersed light Ld reflected by the movable light reflector <NUM>. The part of the beams of light having the different wavelengths included in the wavelength dispersed light Ld is emitted to the outside through the second light passing portion <NUM>. A region of the light emitter <NUM> other than the second light passing portion <NUM> defines a second light non-passing portion <NUM> that does not allow the wavelength dispersed light Ld to pass therethrough.

The second light passing portion <NUM> has, for example, a pinhole shape or a slit shape, and is provided to determine the emission position of the part of the beams of light having the different wavelengths included in the wavelength dispersed light Ld and to increase the wavelength resolution.

The beams of light having the different wavelengths included in the wavelength dispersed light Ld are reflected at different positions on the reflection line <NUM> on the reflecting surface <NUM> and are incident at different positions on an emission line <NUM> on the light emitter <NUM>.

Since the reflecting surface <NUM> of the movable light reflector <NUM> changes the inclination around the swing axis <NUM>, the incident position on the emission line <NUM> of each of the beams of light having the different wavelengths included in the wavelength dispersed light Ld changes.

Among the beams of light having the different wavelengths included in the wavelength dispersed light Ld, light incident on the position of the second light passing portion <NUM> passes through the second light passing portion <NUM> and is emitted. The light emitter <NUM> can emit light having a wavelength included in the wavelength dispersed light Ld and determined by the swing angle of the movable light reflector <NUM> through the second light passing portion <NUM>. Emission light Lo illustrated in <FIG> represents light emitted from the light emitter <NUM>.

The light incidence section <NUM> and the light emitter <NUM> each may be formed on a substrate. In this case, the material of the substrate may be, but is not limited to, for example, a semiconductor, a glass, a metal, or a resin. However, it is desirable to use a semiconductor as the material of the substrate because the light incidence section <NUM> and the light emitter <NUM> can be formed with high precision and at low cost using a semiconductor process, a MEMS process, or the like.

The light detector <NUM> is an example of light detecting means that detects the emission light Lo from the light emitter <NUM>. The light detector <NUM> may use, for example, a photodiode. When light Li in a near infrared region is dispersed, an indium gallium arsenide (InGaAs) photodiode is desirable.

In the spectroscope <NUM>, the above-described components are disposed at predetermined positions as illustrated in <FIG>, and are secured to a housing, a jig, or the like, so as to maintain predetermined postures.

In <FIG>, a circle indicated by a broken line represents a Rowland circle <NUM>. A Rowland circle is a circle having a diameter of a line connecting the center of curvature of the concave diffraction grating <NUM> and the center of a concave curved surface included in the concave diffraction grating <NUM>. In the present embodiment, at least the light incidence section <NUM> and the concave diffraction grating <NUM> are disposed on the Rowland circle <NUM>. The light emitter <NUM> is arranged on the Rowland circle <NUM> depending on the arrangement of the movable light reflector <NUM>; however, <FIG> illustrates a configuration in which the light emitter <NUM> is not arranged on the Rowland circle <NUM> as an example.

<FIG> illustrates a configuration of the concave diffraction grating <NUM>, and is a cross-sectional view taken along line III-III in <FIG>.

As illustrated in <FIG>, the concave diffraction grating <NUM> includes a reflecting member <NUM>. Specifically, a concave curved surface is formed in an upper surface of the substrate <NUM>, and a diffraction grating is formed on the concave curved surface. Furthermore, the reflecting member <NUM> using a metal material, such as aluminum (Al), silver (Ag), gold (Au), or platinum (Pt), for increasing the reflectivity is formed on a surface of the diffraction grating. For example, a resist is applied to the concave curved surface of the substrate <NUM>, a grating pattern is formed in the resist using an interference exposure method or the like, and dry etching or the like is performed, thereby forming a diffraction grating on the concave curved surface of the substrate <NUM>.

The concave diffraction grating <NUM> may have, for example, a rectangular shape, a sine wave shape, or a sawtooth wave shape as the sectional shape of the groove portion of the diffraction grating.

The concave diffraction grating <NUM> does not have to include the reflecting member <NUM>. The configuration of the concave diffraction grating <NUM> is not limited to the one illustrated in <FIG> as long as the concave diffraction grating <NUM> has a similar wavelength dispersion function. When parallel light is incident from the light incidence section <NUM>, a plane diffraction grating may be used instead of the concave diffraction grating <NUM> to obtain a similar wavelength dispersion function. In this case, a complicated device configuration (for example, a collimator optical system for converting light into parallel light at a position in front or rear of the plane diffraction grating) is not used, while the complicated device is used when a configuration that changes the inclination of the plane diffraction grating is employed.

In the concave diffraction grating <NUM>, a resin layer in a thin film form may be formed on the concave curved surface formed in the upper surface of the substrate <NUM>, and a diffraction grating may be formed in the resin layer. In this case, to increase the reflectivity, a reflecting member made of a metal material, such as Al, Ag, Au, or Pt, is desirably formed on a surface of the diffraction grating formed in the resin layer.

<FIG> each illustrate a configuration for a positional change according to the present embodiment. <FIG> is a top view of a first example. <FIG> is a front view of the first example. <FIG> is a top view of a second example. <FIG> is a front view of the second example. <FIG> is a top view of a third example. <FIG> is a front view of the third example.

The spectroscope <NUM> includes a holder <NUM> and two positioning pins <NUM> as a configuration for changing the position of each of the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM>.

In <FIG>, the top view is a view of the holder <NUM> and the positioning pins <NUM> in a direction orthogonal to each of a direction indicated by arrow P and a direction indicated by arrow Q. The direction indicated by arrow P is a direction in which the holder <NUM> slides to change its position. The direction indicated by arrow Q is a direction in which the holder <NUM> comes into contact with the positioning pins <NUM>. The front view is a view of the holder <NUM> and the positioning pins <NUM> in the direction indicated by arrow P.

The configurations of the holder <NUM> and the two positioning pins <NUM> can be appropriately changed in accordance with the position and shape of each of the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> to which the holder <NUM> and the two positioning pins <NUM> are applied. <FIG> illustrate a first example. <FIG> illustrate a second example. <FIG> illustrate a third example.

In the first example, a side surface (a surface orthogonal to the direction indicated by arrow Q) of a holder <NUM> comes into contact with positioning pins <NUM>, and hence the holder <NUM> is positioned in the direction indicated by arrow Q. In this state, the position of the holder <NUM> can be changed in the direction indicated by arrow P.

In the second example, positioning pins <NUM> enter a groove <NUM> formed in a bottom surface (a surface opposite to an upper surface) of the holder <NUM> to position the holder <NUM> in the direction indicated by arrow Q. In this state, the position of the holder <NUM> can be changed in the direction indicated by arrow P.

In the third example, positioning pins <NUM> enter a long hole <NUM> formed in a bottom surface of a holder <NUM> to position the holder <NUM> in the direction indicated by arrow Q. In this state, the position of the holder <NUM> can be changed in the direction indicated by arrow P. The long hole <NUM> may be a hole extending through the holder <NUM> or may be a hole not extending through the holder <NUM> in a direction orthogonal to each of the direction indicated by arrow P and the direction indicated by arrow Q.

An optical spectrum by the spectroscope <NUM> is described referring to <FIG> is a graph presenting an optical spectrum near a wavelength λ1. <FIG> is a graph presenting optical spectra near wavelengths λ1, λ2, and λ3. As illustrated in <FIG>, the optical spectrum represents a light intensity on a wavelength basis.

A graph <NUM> with a solid line indicates an optical spectrum in a state in which the focus position of the emission light Lo substantially matches the position of the second light passing portion <NUM> in the optical-axis direction of the emission light Lo. The peak wavelengths are λ1, λ2, and λ3. In contrast, a graph <NUM> with a broken line indicates an optical spectrum in a state in which the focus position of the emission light Lo does not match the position of the second light passing portion <NUM> in the optical-axis direction of the emission light Lo. The peak wavelengths are λ1', λ2', and λ3'. The positional deviation in the optical-axis direction of the emission light Lo between the focus position of the emission light Lo and the position of the second light passing portion <NUM> is hereinafter referred to as a deviation in the optical-axis direction. Also, hereinafter, when the peak wavelength changes due to a positional variation or the like from the normal state, such as λ1' for λ1, λ2' for λ2, and λ3' for λ3, the phenomenon is referred to as a wavelength shift, and the differences (λ1' - λ1, λ2' - λ2, λ3' - λ3) are referred to as wavelength shift amounts.

As indicated by the graph <NUM> in <FIG>, when there is a deviation in the optical-axis direction, the light intensity decreases and the half value width of the spectrum increases. The decrease in light intensity and the increase in half value width cause decreases in signal/noise (SN) ratio and wavelength resolution in spectral diffraction, and a decrease in performance of the spectroscope <NUM>. Such a deviation in the optical-axis direction is generated in accordance with a dimensional error or an assembly error of each of the components such as the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM>. Even when the spectroscope <NUM> is manufactured within the tolerance range, a deviation in the optical-axis direction may occur due to an error within a range of dimensional tolerance or assembly tolerance of each component.

As presented in <FIG>, when beams of light having the three wavelengths λ1, λ2, and λ3 have deviations in the optical-axis direction, a wavelength shift Δλ2 is generated for the wavelength λ2 that is separated from the wavelength λ1 near the center, and a wavelength shift Δλ3 is generated for the wavelength λ3 that is separated from the wavelength λ1 near the center. When the focus position and the position of the light emitter <NUM> are deviated from each other, the wavelength shift amount of λ1 near the center of the spectral wavelengths is small, whereas the wavelength shift amounts of λ2 and λ3 separated from the center of the spectral wavelengths are large. These wavelength shifts also cause a decrease in performance of the spectroscope <NUM>.

<FIG> illustrates a specific phenomenon. <FIG> is a diagram illustrating a relationship among diffraction angles θλ1, θλ2, and θλ3 when beams of light having the wavelengths λ1, λ2, and λ3 dispersed by the concave diffraction grating <NUM> are reflected by the movable light reflector <NUM>, angles αλ1, αλ2, and αλ3 of the movable light reflector <NUM>, and angles φλ1, φλ2, and φλ3 at which the beams of light are reflected by the movable light reflector <NUM> (in this case, representing the sum of the incident angle and the reflection angle). The beams of light having the wavelengths λ1, λ2, and λ3 represent principal rays. In <FIG>, light having the wavelength λ1 is indicated by a solid line, light having the wavelength λ2 is indicated by a broken line, and light having the wavelength λ3 is indicated by a one dot-chain line.

The diffraction angle is indicated as a rotation angle with respect to the normal direction (Z-axis direction) of the concave diffraction grating <NUM>. It is assumed that the diffraction angle θλ1 coincides with the normal direction, that is, θλ1 = <NUM>. The angle of the movable light reflector <NUM> is indicated while it is assumed that the angle under a condition that the light having the wavelength λ1 passes through the second light passing portion <NUM> is <NUM>°, that is, αλ1 = <NUM>. In an ideal state, θλ1 = αλ = <NUM>, θλ2 = αλ2, and θλ3 = αλ3 are established, and φλ1 = φλ2 = φλ3 is established. As illustrated in <FIG>, the beams of light having the wavelengths are reflected at different positions Pλ1, Pλ2, and Pλ3 of the movable light reflector <NUM>. Thus, for example, when the rotation axis of the movable light reflector <NUM> is deviated from an ideal position, for example, a position on the X-axis orthogonal to each of the Y-axis and the Z-axis illustrated in <FIG>, the beams of light having the wavelengths reach different positions. This is a disadvantage specific to a spectroscope using the movable light reflector <NUM>.

<FIG> presents angles of the movable light reflector <NUM> when light having each of the wavelengths λ1, λ2, and λ3 passes through the second light passing portion <NUM> with the highest light intensity in a case where predetermined tolerances are given to the position and posture of each element of the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM>. A dotted line indicates an angle of a design median value without a positional variation. The larger the difference in angle from the design median value, the larger the wavelength shift amount. The position of each element is adjusted to reduce the variation in angle.

<FIG> presents values of full width at half maximum of light illuminance when light having each of the wavelengths λ1, λ2, and λ3 passes through the second light passing portion <NUM> with the highest light intensity in a case where predetermined tolerances are given to the position and posture of each element of the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM>. A dotted line indicates a value of a design median value without a positional variation. The full width at half maximum increases with a variation in position from the design median value. The wavelength resolution may be defined as the reciprocal of the full width at half maximum.

As described above, to ensure the performance of the spectroscope <NUM> at a high level and to reduce the difference in performance between spectroscopes <NUM>, it is desirable to reduce a deviation in the optical-axis direction.

<FIG> is a diagram illustrating an example in accordance with the claimed invention of positional changes of the concave diffraction grating <NUM> and the light emitter <NUM>. <FIG> is a view illustrating a grating <NUM> of the concave diffraction grating <NUM>. <FIG> are views each illustrating a change in focus position of the emission light Lo when the position of the concave diffraction grating <NUM> is changed. <FIG> illustrates a first example. <FIG> illustrates a second example. <FIG> illustrates a third example.

In the present embodiment, as illustrated in <FIG>, the position of the concave diffraction grating <NUM> can be changed in a first tangential direction <NUM> of the Rowland circle <NUM> near the position at which the concave diffraction grating <NUM> is disposed. As illustrated in <FIG>, in the concave diffraction grating <NUM>, a plurality of gratings <NUM> extending in an extension direction <NUM> are arranged in an arrangement direction <NUM>. The arrangement direction <NUM> is an example of a predetermined direction in which the plurality of gratings <NUM> are arranged. The first tangential direction <NUM> is a direction in the arrangement direction <NUM>, and is a direction substantially orthogonal to the extension direction <NUM>.

Changing the position of the concave diffraction grating <NUM> in the first tangential direction <NUM> changes the incident angle of the light from the light incidence section <NUM> onto the concave diffraction grating <NUM>. Thus, the focus position of the emission light Lo can be changed.

In <FIG>, a focus position Bw of the emission light Lo is located on the movable light reflector <NUM> side with respect to the second light passing portion <NUM> of the light emitter <NUM> in an optical-axis direction <NUM>. In <FIG>, the second light passing portion <NUM> of the light emitter <NUM> and the focus position Bw of the emission light Lo substantially match each other in the optical-axis direction <NUM>. In <FIG>, the focus position Bw of the emission light Lo is located on the side opposite to the movable light reflector <NUM> with respect to the second light passing portion <NUM> of the light emitter <NUM> in the optical-axis direction <NUM>. Changing the position of the concave diffraction grating <NUM> in the first tangential direction <NUM> can change the position of the focus position Bw in the optical-axis direction <NUM> as illustrated in <FIG>. Thus, adjustment can be performed to substantially align the second light passing portion <NUM> and the focus position Bw with each other.

The direction in which the position of the concave diffraction grating <NUM> is changed is the longitudinal direction of the concave diffraction grating <NUM>. Thus, two reference points can be set at positions apart from each other at the positional change, and a deviation of the concave diffraction grating <NUM> in the rotation direction around the grating direction due to the positional change can be suppressed.

In the present embodiment, as illustrated in <FIG>, the position of the light emitter <NUM> is changeable in the optical-axis direction <NUM> of the emission light Lo emitted from the light emitter <NUM>. The optical-axis direction <NUM> of the emission light Lo corresponds to a direction along the center axis of the emission light Lo. Changing the position of the light emitter <NUM> can provide adjustment to substantially align the second light passing portion <NUM> and the focus position Bw with each other.

Scanning with the emission light Lo is provided by the movable light reflector <NUM> in the spectroscope <NUM> in a direction intersecting with the optical-axis direction <NUM>. Thus, the positional deviation of the focus position Bw in the direction intersecting with the optical-axis direction <NUM> does not affect the light intensity, wavelength resolution, and so forth, of the emission light Lo unless the positional deviation extremely varies, and hence the position of the light emitter <NUM> may be changed at least in the optical-axis direction <NUM>.

The positional change of the light emitter <NUM> has a less influence on the optical characteristics other than the change in focus position Bw in the optical-axis direction <NUM> as compared to the positional changes of the other components in the spectroscope <NUM>, and hence the adjustment to substantially align the focus position Bw and the second light passing portion <NUM> with each other can be stably performed.

As described above, in the present embodiment, the positions of the components in the spectroscope <NUM> can be adjusted. In the present embodiment, the position of the concave diffraction grating <NUM> is changed in the first tangential direction <NUM> of the Rowland circle <NUM>, or the position of the light emitter <NUM> is changed in the optical-axis direction <NUM>, thereby substantially aligning the focus position Bw of the emission light Lo with the position of the second light passing portion <NUM>. Since the focus position Bw of the emission light Lo is substantially aligned with the position of the second light passing portion <NUM>, an individual difference in performance of each spectroscope <NUM> can be reduced.

For example, the position of the light emitter <NUM> can be changed so that the focus position Bw of the emission light Lo to be emitted from the light emitter <NUM> overlaps the position at which the emission light Lo to be emitted from the light emitter <NUM> passes through the light emitter <NUM>. The position of each of the concave diffraction grating <NUM> and the light emitter <NUM> may be changeable so that the light intensity of the emission light Lo from the light emitter <NUM> is maximized. The position of each of the concave diffraction grating <NUM> and the light emitter <NUM> may be changeable so that the wavelength resolution of the emission light Lo from the light emitter <NUM> is maximized. The position of each of the concave diffraction grating <NUM> and the light emitter <NUM> may be changeable so that the wavelength shift of the emission light Lo from the light emitter <NUM> is minimized. Furthermore, two or more of the above-described positional changes may be combined as appropriate. With any of the positional changes, an advantageous effect of reducing the individual difference in performance of each spectroscope <NUM> can be obtained.

<FIG> is a diagram illustrating an example of a positional change of the light incidence section <NUM>. When the position of the light incidence section <NUM> is changed in a second tangential direction <NUM> or a radial direction <NUM> of the Rowland circle <NUM> near the position at which the light incidence section <NUM> is disposed, the relative positions of the concave diffraction grating <NUM> and the light incidence section <NUM> are changed. Accordingly, an advantageous effect similar to that in the case where the position of the concave diffraction grating <NUM> is changed in the first tangential direction <NUM> can be obtained. Which one of the second tangential direction <NUM> and the radial direction <NUM> the position is changed along can be appropriately selected in accordance with the clearance with respect to another component, the space in which the position can be changed, and so forth.

<FIG> is a diagram illustrating an example of a positional change of the movable light reflector <NUM>. As illustrated in <FIG>, when the position of the movable light reflector <NUM> is changed in a direction away from the concave diffraction grating <NUM> in a movement direction <NUM>, the focus position Bw of the emission light Lo changes to a position on the movable light reflector <NUM> side with respect to the light emitter <NUM>. The movable light reflector <NUM> changes the position in the optical-axis direction of the light incident on the movable light reflector <NUM> to change the focus position Bw of the emission light Lo and to substantially align the focus position Bw with the position of the second light passing portion <NUM> of the light emitter <NUM>. Example of Positional Changes of Light Incidence Section <NUM>, Concave Diffraction Grating <NUM>, Movable Light Reflector <NUM>, and Light Emitter <NUM>.

<FIG> is a diagram illustrating an example in a state in which the position of each of the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> is changeable. The positions of at least two of the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> are changeable, and hence the focus position Bw can be substantially aligned with the position of the second light passing portion <NUM> of the light emitter <NUM> even when the dimensional tolerance, mounting tolerance, or assembly tolerance of each of the components is large. Accordingly, robustness with respect to a manufacturing error or the like of each component can be enhanced, performance of the spectroscope <NUM> can be highly ensured, and an individual difference of the spectroscope <NUM> can be reduced. In addition, the positions of the plurality of components can be changed, and hence the range of change in position per component can be decreased, thereby downsizing the spectroscope <NUM>.

Each of the components in the spectroscope <NUM> including the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> is secured in a housing or by a support so as to maintain the predetermined position and posture. Thus, the position of each of the components may be changed by changing the position of the support. There is no particular limitation on the system, shape, or the like, of the position change mechanism.

When the light detector <NUM> is installed near the light emitter <NUM>, the position of the light emitter <NUM> can be changed simultaneously with the positional change of the light detector <NUM>. By performing the positional changes simultaneously, a deviation in alignment between the light emitter <NUM> and the light detector <NUM> is not generated, and the optical characteristics of the spectroscope <NUM> can be stabilized.

<FIG> are views illustrating an example of an angle adjustment mechanism <NUM> of the concave diffraction grating <NUM>. <FIG> is a cross-sectional view, and <FIG> is a bottom view. As illustrated in <FIG>, the angle adjustment mechanism <NUM> has a recessed portion 23a in a lower surface 22d. The recessed portion 23a is fitted to a positioning pin 23b having a columnar shape. The positioning pin 23b has a columnar shaft that is substantially parallel to the vertical direction, and substantially coincides with a rotation axis 2c of the angle adjustment mechanism <NUM>.

The angle adjustment mechanism <NUM> swings around the rotation axis 2c (in a direction indicated by arrow <NUM>) to swing the concave diffraction grating <NUM> held by the angle adjustment mechanism <NUM> around the rotation axis 2c. An angle adjustment mechanism <NUM>' in <FIG> represents an angle adjustment mechanism before the swing, and the angle adjustment mechanism <NUM> represents an angle adjustment mechanism after the swing by a predetermined rotation angle around the rotation axis 2c from the state of the angle adjustment mechanism <NUM>'.

<FIG> illustrate another example of the angle adjustment mechanism of the concave diffraction grating <NUM>. <FIG> is a cross-sectional view, and <FIG> is a bottom view. As illustrated in <FIG>, the angle adjustment mechanism <NUM> has a recessed portion 25a in the lower surface 22d. The recessed portion 25a is fitted to a guide member 25b having a columnar shape. The guide member 25b has a columnar shaft that is substantially parallel to the vertical direction, and substantially coincides with the rotation axis 2c of the angle adjustment mechanism <NUM>.

The angle adjustment mechanism <NUM> swings around the rotation axis 2c (in a direction indicated by arrow <NUM>) to swing the concave diffraction grating <NUM> held by the angle adjustment mechanism <NUM> around the rotation axis 2c.

In the present embodiment, a spectroscope <NUM> includes a light incidence section <NUM> (light incidence means) that allows light Li from an outside to be incident; a concave diffraction grating <NUM> (diffraction grating) that disperses wavelengths of the light Li incident on the concave diffraction grating <NUM> by the light incidence section <NUM>; a movable light reflector <NUM> (reflecting means) having a reflecting surface <NUM> having an inclination variable around a rotation axis of the reflecting surface <NUM>; and a light emitter <NUM> (light emitting means) that emits the light reflected by the movable light reflector <NUM> to the outside. At least two of positions of the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> are changeable in a direction orthogonal to the rotation axis of the reflecting surface <NUM>. The position of the light emitter <NUM> is changeable in a direction along a center axis of the light emitted from the light emitter <NUM>. With this configuration, the positions of components in the spectroscope can be adjusted.

In the present embodiment, at least one of the positions of the light incidence section <NUM>, the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> is adjustable in a direction orthogonal to the rotation axis of the reflecting surface <NUM>. With this configuration, regardless of the dimensional tolerance or assembly tolerance of a component, a decrease in light intensity of emission light, a deterioration in wavelength resolution, and a deterioration in wavelength precision can be suppressed, and an individual difference in spectral performance can be reduced.

In the present embodiment, the position of the concave diffraction grating <NUM> may be adjustable, and based on an assumption that a direction along the rotation axis of the movable light reflector <NUM> is an X-axis, a direction from a center of the concave diffraction grating <NUM> toward a center of curvature of the concave diffraction grating <NUM> is a Z-axis, and an axis orthogonal to each of the X-axis and the Z-axis is a Y-axis, the position of the concave diffraction grating <NUM> may be adjustable in a direction along the Y-axis. With this configuration, the positions of the concave diffraction grating <NUM> and the light emitter <NUM> are adjustable, and hence the spectral performance can be stably improved.

In the present embodiment, the position of the concave diffraction grating <NUM> may be adjusted so that the light incidence section <NUM> and the light emitter <NUM> are located on a Rowland circle formed by the concave diffraction grating <NUM>. With this configuration, a Rowland arrangement can be provided, and the spectral performance can be increased. <FIG> is a graph presenting angles of the movable light reflector <NUM> in a case where predetermined tolerances are given to the position and posture of each of the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> and the position of the concave diffraction grating <NUM> is adjusted. As illustrated in <FIG>, adjusting the position of the concave diffraction grating <NUM> can significantly reduce a variation in angle.

In the present embodiment, the position of the light emitter <NUM> may be adjustable, and based on an assumption that a direction along the rotation axis of the movable light reflector <NUM> is an X-axis, a direction normal to a surface of the light emitter <NUM> is a Z-axis, and an axis orthogonal to each of the X-axis and the Z-axis is a Y-axis, the position of the light emitter <NUM> may be adjustable in a direction along the Z-axis. With this configuration, the positions of the concave diffraction grating <NUM> and the light emitter <NUM> are adjustable, and hence the spectral performance can be stably improved. <FIG> is a graph presenting values of full width at half maximum of light illuminance when light having each of the wavelengths λ1, λ2, and λ3 passes through the second light passing portion <NUM> with the highest light intensity in a case where predetermined tolerances are given to the position and posture of each of the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> and the position of the light emitter <NUM> is adjusted. As illustrated in <FIG>, adjusting the light emitter <NUM> can reduce an increase in full width at half maximum.

In the present embodiment, the position of the light emitter <NUM> may be adjusted so that the light incidence section <NUM> and the light emitter <NUM> have an optically conjugate relationship. With this configuration, the focus position can be aligned with the position of the second light passing portion <NUM>, and the spectral performance can be increased.

In the present embodiment, each of the positions of the concave diffraction grating <NUM> and the light emitter <NUM> may be adjustable, and each of the concave diffraction grating <NUM> and the light emitter <NUM> may be disposed at a position at which a wavelength shift is minimized. With this configuration, it is possible to reduce the wavelength shift that is wavelength-dependent, thereby increasing the wavelength precision and increasing the spectral performance.

In the present embodiment, each of the positions of the concave diffraction grating <NUM> and the light emitter <NUM> may be adjustable, and each of the concave diffraction grating <NUM> and the light emitter <NUM> may be disposed at a position at which a wavelength resolution is maximized. With this configuration, the wavelength resolution is increased, and hence the spectral performance can be increased. <FIG> is a graph presenting values of full width at half maximum of light illuminance when light having each of the wavelengths λ1, λ2, and λ3 passes through the second light passing portion <NUM> with the highest light intensity in a case where predetermined tolerances are given to the position and posture of each of the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> and the positions of the concave diffraction grating <NUM> and the light emitter <NUM> are adjusted simultaneously. As illustrated in <FIG>, adjusting the positions of the concave diffraction grating <NUM> and the light emitter <NUM> simultaneously can reduce an increase in full width at half maximum as compared to the case where the position of the light emitter <NUM> is adjusted.

In the present embodiment, each of the positions of the concave diffraction grating <NUM> and the light emitter <NUM> may be adjustable, and each of the concave diffraction grating <NUM> and the light emitter <NUM> may be disposed at a position at which a light intensity of light passing through the light emitter <NUM> is maximized. Maximizing the light intensity of light passing through the light emitter <NUM> can increase the SN ratio and increase the spectral performance.

In the present embodiment, at least one of postures of the light incidence section <NUM>, the concave diffraction grating <NUM>, and the light emitter <NUM> may be rotated around an axis parallel to the rotation axis of the movable light reflector <NUM> to adjust the at least one of the postures of the light incidence section <NUM>, the concave diffraction grating <NUM>, and the light emitter <NUM>. With this configuration, regardless of the dimensional tolerance or assembly tolerance of a component, a decrease in light intensity of emission light, a deterioration in wavelength resolution, and a deterioration in wavelength precision can be suppressed, and an individual difference in spectral performance can be reduced.

In the present embodiment, the posture of the concave diffraction grating <NUM> may be adjustable, and the axis parallel to the rotation axis of the movable light reflector <NUM> may pass through a center of the concave diffraction grating <NUM>. <FIG> is a graph presenting angles of the movable light reflector <NUM> in a case where predetermined tolerances are given to the position and posture of each of the concave diffraction grating <NUM>, the movable light reflector <NUM>, and the light emitter <NUM> and the posture of the concave diffraction grating <NUM> is adjusted. As illustrated in <FIG>, adjusting the posture of the concave diffraction grating <NUM> can significantly reduce a variation in angle.

An analysis system <NUM> including the spectroscope <NUM> according to the first embodiment is described next as a second embodiment. The same name and reference sign of the above-described embodiment denote members or components identical or equivalent to those of the above-described embodiment, and the detailed description thereof is appropriately omitted.

<FIG> illustrates an example of a general arrangement of the analysis system <NUM>. As illustrated in <FIG>, the analysis system <NUM> includes a portable apparatus <NUM> and a portable terminal <NUM>. The portable apparatus <NUM> includes the spectroscope <NUM>, a processor <NUM>, and a communication circuit <NUM>.

The analysis system <NUM> may have a configuration in which one spectroscope <NUM> is provided for one portable terminal <NUM>, or a configuration in which a plurality of spectroscopes <NUM> are provided for one portable terminal <NUM>.

The processor <NUM> receives an input of an electric signal that is output from the spectroscope <NUM>, and acquires information in which a time of an optical spectrum is associated with an output including a light intensity by computation. The communication circuit <NUM> outputs the result obtained by the processor <NUM> to the portable terminal <NUM>.

The portable terminal <NUM> includes an interface <NUM>, a processor <NUM>, and a communication circuit <NUM>. The portable terminal <NUM> is, for example, a portable device such as a smartphone or a tablet terminal. The portable terminal <NUM> may have a camera function.

The processor <NUM> receives information Sp associated with the output including the time of the optical spectrum and the light intensity output from the communication circuit <NUM> of the portable apparatus <NUM> using the communication circuit <NUM>. The processor <NUM> converts the time into a wavelength of light based on the received information Sp and a rotation frequency, a rotation angle amplitude, or the like, of the movable light reflector <NUM> included in the spectroscope <NUM> to obtain optical spectrum information Sq defined in relation to a light intensity on a wavelength of light basis. The processor <NUM> also acquires an analysis result such as a composition determination result of an object <NUM> by computation using the obtained optical spectrum information Sq.

The processor <NUM> can display the analysis result on a display <NUM> via the interface <NUM>.

In the analysis system <NUM>, the portable apparatus <NUM> transmits data to the portable terminal <NUM> via the communication circuit <NUM> using, for example, wireless serial communication such as Bluetooth®. The portable terminal <NUM> receives data from the portable apparatus <NUM> and processes and analyzes the data using the processor <NUM>. The analysis system <NUM> causes the display <NUM> to display, for example, the optical spectrum information Sq and the composition determination result, which are the analysis result. Example of Operation of Analysis System <NUM>
<FIG> is a flowchart presenting an example of a resin determination operation when the analysis system <NUM> is applied to a resin determination apparatus.

In step S1, the analysis system <NUM> provides an object including a resin to be classified or identified.

In step S2, the analysis system <NUM> stores one or more infrared material classification models (multivariate classification models) in a memory.

In step S3, the analysis system <NUM> executes spectroscopic analysis on the object <NUM> to collect raw infrared spectrum data.

In step S4, the analysis system <NUM> executes multivariate processing on the raw infrared spectrum data using the processor <NUM> of the portable terminal <NUM>.

In step S5, the analysis system <NUM> uses the processor <NUM> of the portable terminal <NUM> to identify the composition of a sample as a resin-based composite material of a specific type (corresponding to the material model).

In step S6, the analysis system <NUM> further processes the object <NUM> (for example, stores the object <NUM> in a proper location for a further recycle step). The analysis system <NUM> can repeat each processing from step S1 to step S6 for an object <NUM> including another resin in step S3.

For example, the analysis system <NUM> uses a classification model to identify the composition of the object <NUM> including a resin, and determines a resin that a sample including a specific resin may include. For example, determining a resin using the analysis system <NUM> can optimize processing conditions of a process such as optimizing processing conditions of a furnace to be used for material processing in the recycle of the object <NUM> including the resin.

Moreover, processing of registering known material data before execution of the spectroscopic analysis in the operation in <FIG> can be added. With this processing, the precision of the analysis result of the object <NUM> can be increased. As described above, the analysis system <NUM> can determine a resin with high reliability.

For example, the spectroscope <NUM> according to the embodiment may be used for an analysis apparatus. For example, such an analysis apparatus is used to identify the type of resin or the like of an object by spectroscopic analysis on the spectrum obtained by the spectroscope <NUM>, and to sort and recover the object for each type of resin as a recycled material. Since the analysis apparatus includes the spectroscope <NUM>, highly precise analysis in which the influence of stray light is reduced can be performed, and the analysis apparatus can be downsized.

Claim 1:
A spectroscope comprising:
light incidence means (<NUM>) comprising a first light passing portion (<NUM>) configured to allow light from an outside to be incident on the spectroscope and a first light non-passing portion (<NUM>) configured to not allow the light to pass to the spectroscope;
a reflective concave diffraction grating (<NUM>) configured to disperse wavelengths of the light incident on the diffraction grating (<NUM>) by the light incidence means (<NUM>);
reflecting means (<NUM>) configured to receive the wavelength dispersed light from the diffraction grating (<NUM>) having a reflecting surface having an inclination variable around a rotation axis of the reflecting surface; and
light emitting means (<NUM>) comprising a second light passing portion (<NUM>) configured to emit the light reflected by the reflecting means (<NUM>) to the outside and a second light non-passing portion (<NUM>) configured to not allow the light reflected by the reflecting means (<NUM>) to pass to the outside,
wherein the position of the light emitting means (<NUM>) is changeable in a direction (<NUM>) along a center axis of the light emitted from the light emitting means (<NUM>),
wherein the position of the light emitting means (<NUM>) is adjustable so that the light incidence means (<NUM>) and the light emitting means (<NUM>) have an optically conjugate relationship,
wherein the light incidence means (<NUM>) and the concave diffraction grating are arranged on a Rowland circle,
characterized in that
the position of the concave diffraction grating is changeable in a tangential direction (<NUM>) of the Rowland circle at the position at which the concave diffraction grating is disposed.