Evaluation apparatus and evaluation method

• US 7,468,792 B2
• Filed: 12/19/2007
• Issued: 12/23/2008
• Est. Priority Date: 03/22/2004
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Masaki, Yuichi, Akino, Yutaka
• Primary Examiner(s): Lauchman; L. G
• Assistant Examiner(s): Underwood; Jarreas C
• Application Number:
  US11/959,810
• Publication Number:
  US 20080100838A1
• Time in Patent Office: 370 Days
• Field of Search: 356300-334, 356364-370, 356450-456
• US Class Current: 356/326
• CPC Class Codes: G01J 3/2823 Imaging spectrometer
• CPC Class Codes: G01N 21/31 Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry G01N21/72 takes precedence
• CPC Class Codes: G01N 21/55 Specular reflectivity

Abstract

An evaluation apparatus which evaluates a sample. The apparatus includes a light source which irradiates the sample with light, an imaging spectrometer which spectroscopically measures light reflected by the sample and senses an image, a first calculator which obtains amplitude information on an amplitude of a spectral reflectance of the sample based on the image sensed by the imaging spectrometer within a predetermined wavelength range of spectral reflectance spectra obtained by the spectrometer, a memory which holds in advance relationship information representing a relationship between the amplitude information of the spectral reflectance and an absorption coefficient, and a second calculator which obtains an absorption coefficient of the sample based on the amplitude information obtained by the first calculator and the relationship information held in the memory.

Claims

1. An evaluation apparatus which evaluates a sample, the apparatus comprising:

a light source which irradiates the sample with light;

an imaging spectrometer which spectroscopically measures light reflected by the sample and senses an image;

a first calculator which obtains amplitude information on an amplitude of a spectral reflectance of the sample based on the image sensed by the imaging spectrometer within a predetermined wavelength range of spectral reflectance spectra obtained by the spectrometer;

a memory which holds in advance relationship information representing a relationship between the amplitude information of the spectral reflectance and an absorption coefficient; and

a second calculator which obtains an absorption coefficient of the sample based on the amplitude information obtained by the first calculator and the relationship information held in the memory;

wherein the relationship information includes information representing a relationship between amplitude information of a spectral reflectance of a sample having a porous layer and an absorption coefficient of the porous layer.

2. The apparatus according to claim 1, wherein the amplitude information includes an average amplitude of the spectral reflectance.

3. The apparatus according to claim 1, wherein the relationship information includes an approximate expression representing the relationship between the amplitude information of the spectral reflectance and the absorption coefficient.

4. The apparatus according to claim 1, further comprising an outputting unit which outputs the absorption coefficient obtained by the second calculator.

5. The apparatus according to claim 1, further comprising:

a data processor which converts the absorption coefficient obtained by the second calculator into a gradation value and maps the gradation value in a two-dimensional space to generate an image representing an evaluation result; and

an outputting unit which outputs the image obtained by the data processor.

6. An evaluation method of evaluating a sample, the method comprising:

an imaging spectrometry step of spectroscopically measuring light reflected by the sample irradiated with light and sensing an image;

a first calculation step of obtaining amplitude information on an amplitude of a spectral reflectance of the sample based on the image sensed in the imaging spectrometry step within a predetermined wavelength range of spectral reflectance spectra obtained in the spectrometry step; and

a second calculation step of obtaining an absorption coefficient of the sample based on the amplitude information obtained in the first calculation step, and relationship information which is held in a memory in advance and represents a relationship value between the amplitude information of the spectral reflectance and an absorption coefficient;

wherein the relationship information includes information representing a relationship between amplitude information of a spectral reflectance of a sample having a porous layer and an absorption coefficient of the porous layer.

7. The method according to claim 6, wherein the amplitude information includes an average amplitude of the spectral reflectance.

8. The method according to claim 6, wherein the relationship information includes an approximate expression representing the relationship between the amplitude information of the spectral reflectance and the absorption coefficient.

9. The method according to claim 6, further comprising an outputting step of outputting the absorption coefficient obtained in the second calculation step.

10. The method according to claim 6, further comprising:

a data processing step of converting the absorption coefficient obtained in the second calculation step into a gradation value and mapping the gradation value in a two-dimensional space to generate an image representing an evaluation result; and

an outputting step of outputting the image obtained in the data processing step.