JP2006322710A - Spectrometry device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a spectrometry device capable of measuring simultaneously angle information and spectral intensity information of radiated or reflected light. <P>SOLUTION: This device has: the first lens group having a focal point position on one point of a measuring object, for collimating the radiated or reflected light; the second lens group for imaging the collimated light on a slit position of a two-dimensional spectroscope, the two-dimensional spectroscope for spectrally diffracting light passing the slit to form a two-dimensional spectral image; an imaging means; and a data processing device. The device measures simultaneously a radiation (reflection) angle and the spectral intensity. When performing spectroscopic measurement of the reflected light, the device preferably has a light source and an optical system comprising a combination between a lens and a pinhole, and is equipped with an irradiation means for changing the light from the light source into spot light. When measuring a polarization characteristic, preferably the device is equipped with a polarizer for polarizing the light from the light source on an optical path of the irradiation means, and an analyzer is disposed on an optical path between the the first lens group and the two-dimensional spectroscope. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a spectrometer for light emitted or reflected from an object to be measured, and more particularly to measurement of a radiation angle or reflection angle distribution of spectral intensity.

In spectroscopic measurement, generally, radiation or reflected light from an object to be measured is taken into a spectroscope, and information about the spectral intensity, that is, the wavelength and the intensity of light for each wavelength is obtained. In addition, when spectroscopic measurement is performed on light from a minute point (measurement point), the light is taken into the spectroscope through a lens having a focus at the measurement point.
However, the conventional spectroscopic measurement apparatus has a problem that the spectral intensity of the radiation or reflected light from the measurement object cannot be measured simultaneously as a function of the radiation angle or the reflection angle. In a conventional spectrometer, in order to measure the radiation angle distribution or reflection angle distribution of the spectral intensity for light from a small point (measurement point), the spectroscope is placed in the radiation angle direction or reflection angle direction with respect to the measurement point. A method of changing the radiation angle or reflection angle of light reaching the spectroscope by moving it with a goniometer or moving the optical system (mirror system) is used. It was necessary to measure the intensity individually.

  In order to solve such a problem, Patent Document 1 discloses a scattering intensity measuring apparatus that can measure the intensity of scattered light as a function of a scattering angle, although it is not spectroscopic measurement. In the apparatus described in Patent Document 1, an irradiation light source for irradiating a sample with light, and a reflecting mirror preferably configured to reflect and collect scattered light from the sample, preferably a part of a spheroid surface An image forming lens for forming an image on the surface of the reflecting mirror, a stop, and an image pickup means for recording the image formed by the image forming lens, without moving the elements constituting the optical system It is possible to measure the angle dependence of the scattered light scattering intensity at a time over a wide angle range.

  However, the apparatus described in Patent Document 1 has the problem that although the angular distribution of scattered light intensity can be obtained, the spectral intensity cannot be measured. That is, since the angle distribution image of the two-dimensional scattered light intensity obtained by the apparatus of Patent Document 1 is curved and the curved image cannot be taken into the spectrometer, this apparatus is immediately applied to the spectroscopic measurement. It is not possible. In addition, in order to obtain the angle dependency of the scattering intensity from the scattering angle distribution image of the scattering intensity obtained by the apparatus described in Patent Document 1, it is necessary to consider the influence of the curvature of the optical system, so that complicated calculation is required. As a result, it is difficult to ensure accuracy and time is required for calculation.

Non-Patent Document 1 describes a description of a two-dimensional spectrometer, and describes a two-dimensional spectrometer capable of simultaneously measuring a partial position of an object and a spectral intensity (light spectrum) at each position. Yes. However, the two-dimensional spectroscope described in Non-Patent Document 1 has a problem in that it is impossible to simultaneously measure the relationship between the radiation angle or the reflection angle and the spectral intensity for radiation or reflected light from a minute point.
Japanese Patent No. 3234183 Susumu Moriya: Hikari Alliance vol.10 No.11 (1999.11) p.4-9, published by Nihon Kogyo Publishing

  In view of the problems of the prior art, the present invention provides angle information and spectral intensity information of light emitted from or reflected from one point (measurement point) of the measurement object without moving the measurement object or the spectroscope. An object of the present invention is to propose a spectroscopic measurement apparatus that can measure the above and the like simultaneously.

  In order to achieve the above-described problems, the present inventors diligently studied a method for simultaneously measuring angle information and spectral intensity information of light emitted or reflected from one point (measurement point) of a measurement object. As a result, a lens group having a focal point at the position of the measurement point is disposed, and it has been conceived that the light corresponding to the radiation or reflection angle from the measurement point is spatially parallel light. Spectroscopic measurement that can simultaneously measure the angle information and spectral intensity information of the emitted or reflected light by capturing the parallel light into the two-dimensional spectrometer so that it forms an image at the slit position of the two-dimensional spectrometer. It has been found that is possible.

The present invention has been completed based on the above findings and further studies. That is, the gist of the present invention is as follows.
(1) A spectroscopic measurement apparatus for spectroscopically measuring light emitted from a measurement object, having a focal position at the measurement target point of the measurement target, and collimating the light emitted from the measurement target point A first lens group, a second lens group that forms an image of the collimated light at the slit position of the two-dimensional spectrometer, and an image formed at the slit position and passed through the slit. A two-dimensional spectrometer that splits the light emitted from the measurement target point into a two-dimensional spectral image, an imaging unit that captures the two-dimensional spectral image, and data processing that performs data processing on the captured two-dimensional spectral image And a radiation angle distribution of the spectral intensity by simultaneously measuring the radiation angle and the spectral intensity.

  (2) A spectroscopic measurement device that spectroscopically measures light reflected from an object to be measured, which includes a light source and an optical system that is a combination of a lens and a pinhole, and uses light from the light source as spot light. A focal position at the measurement target point of the measurement target, the irradiation means irradiating the measurement target point of the measurement target, further collimating the light reflected from the measurement target point of the irradiated spot light A first lens group having a second lens group that forms an image of the collimated light at the slit position of the two-dimensional spectrometer, and an image formed at the slit position and passing through the slit. A two-dimensional spectroscope that splits the light reflected from the measurement target point into a two-dimensional spectroscopic image, an image pickup unit that picks up the two-dimensional spectroscopic image, and data that processes the picked-up two-dimensional spectroscopic image And a reflection angle And spectral intensity is measured at the same time, spectroscopic measurement apparatus, characterized in that to obtain a reflection angle distribution of the spectral intensity of the measured points.

  (3) In (2), the irradiating means includes a polarizer for polarizing the light from the light source on the optical path, and is detected on the optical path between the first lens group and the two-dimensional spectrometer. A spectroscopic measurement apparatus characterized by arranging photons.

  According to the present invention, it becomes possible to simultaneously measure angle information and spectral intensity information of light emitted from or reflected from one point (measurement point) of a measurement object, and the accuracy of spectroscopic measurement is improved. Thus, the spectroscopic measurement apparatus can be miniaturized, and the industrial effect is remarkable. In addition, according to the present invention, there is an effect that the measurement of the polarization characteristic is facilitated.

  The spectroscopic measurement apparatus according to the present invention includes a first lens group 2, a second lens group 3, a two-dimensional spectrometer 4, an imaging unit 5, and a data processing device 6 as a basic configuration. An example of the configuration of the spectrometer of the present invention is schematically shown in FIG. FIG. 1 shows an example of spectroscopic measurement of light emitted from one point (measurement point) of the measurement object 1, but the measurement principle is the same even in the case of reflected light.

  The first lens group 2 is configured by combining a plurality of lenses, having a focal point at the position of the measurement point of the measurement object 1, and allowing incident light to be collimated. The light radiated from one point (measurement point) of the measurement object 1 is guided to the first lens group 2 as described above, and is made to be spatially parallel light according to the radiation angle. In the present invention, it is important in the subsequent spectroscopic measurement that the emitted light is spatially parallel according to the radiation angle. In FIG. 1, the mirror 10 is disposed and the direction of the parallel light is changed. However, this is for the purpose of downsizing the apparatus, and the present invention is not limited to this. The mirror 10 is disposed as necessary. Is preferred.

The collimated light is then guided to the second lens group 3.
The second lens group 3 has a plurality of lenses, and is configured so that incident parallel light can be imaged at the position of the slit 4 a of the two-dimensional spectrometer 4. The parallel light guided to the second lens group 3 is imaged by the second lens group 3 at the position of the slit 4a. Thereby, the information on the radiation angle of the emitted light can be projected in the width direction of the slit.

The light emitted from the measurement point and imaged at the position of the slit 4a passes through the slit 4a and is then dispersed by the two-dimensional spectrometer 4.
The two-dimensional spectrometer 4 includes a slit 4a, a lens 4b1, a spectroscopic element 4c, and a lens 4b2. An example of the configuration of the two-dimensional spectrometer 4 is schematically shown in FIG. The spectroscopic element 4c includes a front-stage prism 4c1, a diffraction grating (transmission type) 4c2, and a rear-stage prism 4c3. In addition, it is preferable that the slit and the spectroscopic element can be appropriately selected according to the measurement target.

The light that has passed through the slit 4a is collimated by the lens 4b1, is split by the spectroscopic element 4c, and is split into the image sensor surface of the imaging means 5 provided on the exit side of the two-dimensional spectrometer 4 by the rear lens 4b2. Formed and stored as a two-dimensional spectral image.
The image pickup means 5 is not particularly limited as long as it can pick up a split two-dimensional spectral image, and is preferably a normal CCD camera in which CCD image pickup devices are two-dimensionally arranged. As shown in FIG. 4, the two-dimensional spectroscopic image obtained on the image pickup device surface of the image pickup means 5 is displayed with one axis as slit position information and the other axis as wavelength information. It becomes the intensity of each wavelength. In the present invention, as described above, the position information (slit width direction) of the slit 4a of the two-dimensional spectroscope 4 is the angle information of the radiation or reflected light, and therefore, from the obtained two-dimensional spectroscopic image. The angle information and spectral intensity information of the radiation or reflected light from the measurement point can be measured simultaneously.

  A data processing device 6 that performs data processing of the captured two-dimensional spectral image is connected to the imaging unit 5, and an output from the imaging device of the imaging unit 5 is taken in, and data processing of the obtained two-dimensional spectral image is performed. . The data processing device 6 includes a computer (not shown) capable of executing calculations for associating spectral intensity information and radiation (reflection) angle information from the obtained two-dimensional spectral image, and a display for displaying the calculation results on a drawing or the like. Needless to say, means (not shown) and storage means (not shown) for storing these data are included.

An example of the result of data processing is schematically shown in FIG. 5A shows the relationship between wavelength and radiation angle, FIG. 5B shows the relationship between light intensity and radiation angle at a certain wavelength, and FIG. 5C shows the relationship between light intensity and wavelength at a certain angle. Are shown respectively. According to the present invention, such a relationship can be obtained by a single measurement.
FIG. 2 shows an example of a spectroscopic measurement device in the case of performing spectroscopic measurement of light reflected at one point (measurement point) of a measurement object. When spectroscopically measuring the reflected light, the configuration of the main part of the spectroscopic measurement device is the same as when measuring the emitted light, but irradiation is performed to irradiate a spot (measurement point) with one spot (measurement point). Means 20 are required. The irradiation unit 20 includes a light source 21 and an optical system that is a combination of lenses 21 and 23 and a pinhole 24. With this optical system, the light from the light source 21 is converted into spot light. The spot light obtained by the irradiation means 20 is reflected by the half mirror 25 and irradiated to one point (measurement point) of the measurement object 1. The half mirror 25 transmits reflected light from the object to be measured, and may not be necessary depending on the arrangement of the devices, and may be disposed as necessary.

  The irradiated light is reflected at the measurement point, passes through the half mirror 25, enters the first lens group 2, is collimated in the same manner as the radiated light, and is split by the second lens group 3 into the slit 4a. The image is formed at the position, dispersed through the two-dimensional spectrometer 4, and a two-dimensional spectral image is displayed on the imaging means 5. The obtained two-dimensional spectroscopic image is picked up by the image pickup means 5, output from the image pickup means 5, processed by the data processing device 6 and displayed in the same manner as the emitted light.

  When measuring polarization characteristics, the polarizer 31 and the analyzer 32 are disposed in the optical path. In FIG. 2, a polarizer 31 that polarizes light from the light source 21 is provided on the optical path of the irradiation means, and an analyzer 32 is provided on the optical path between the first lens group 2 and the two-dimensional spectrometer 4. The case where it is arrange | positioned so that attachment or detachment is possible is shown. By disposing the polarizer 31 and the analyzer 32, the light emitted from the light source 21 becomes light having polarization characteristics, and the polarization characteristics of reflected light can be measured.

It is the schematic which shows an example of the spectrometer of this invention typically. It is the schematic which shows typically another example of the spectrometry apparatus of this invention. It is explanatory drawing which shows typically the structure of the two-dimensional spectrometer suitable for this invention. It is explanatory drawing which shows typically the relationship between the two-dimensional spectrometer in this invention, and an imaging means. It is a graph which shows typically the data measured with the spectrometer of the present invention.

Explanation of symbols

1 Measurement Object 2 First Lens Group 3 Second Lens Group 4 Two-dimensional Spectrometer
4a Slit
4b1, 4b2, lens
4c Spectrometer
4c1, 4c3 prism
4c2 Diffraction grating 5 Imaging means 6 Data processing device
10 Mirror
20 Irradiation means
21 Light source
22, 23 Lens
24 pinhole
25 half mirror
31 Polarizer
32 Analyzer

Claims (3)

  A spectroscopic measurement apparatus for spectroscopically measuring light emitted from an object to be measured, wherein the first object has a focal position at a measurement target point of the measurement target and converts the light emitted from the measurement target point into parallel light A second lens group that forms an image of the collimated light at the slit position of the two-dimensional spectrometer, and the measurement object that has been imaged at the slit position and has passed through the slit. A two-dimensional spectroscope that splits light emitted from a point into a two-dimensional spectral image, an imaging unit that captures the two-dimensional spectral image, and a data processing device that processes the captured two-dimensional spectral image A spectroscopic measurement device comprising:   A spectroscopic measurement device for spectroscopically measuring light reflected from an object to be measured, comprising a light source and an optical system that is a combination of a lens and a pinhole, and measuring the light from the light source as spot light. An irradiation means for irradiating the measurement target point of the object, and further, a light beam reflected from the measurement target point of the irradiated spot light is collimated and has a focal position at the measurement target point of the measurement target One lens group, a second lens group that forms an image of the collimated light at the slit position of the two-dimensional spectrometer, and the measurement that has been imaged at the slit position and passed through the slit A two-dimensional spectroscope that splits light reflected from a target point into a two-dimensional spectral image, an imaging means that images the two-dimensional spectral image, and a data processing device that processes the captured two-dimensional spectral image Characterized by having Spectroscopic measurement device that.   The irradiating means includes a polarizer for polarizing light from the light source on an optical path, and an analyzer is disposed on the optical path between the first lens group and the two-dimensional spectrometer. The spectroscopic measurement device according to claim 2.

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