Specimen measuring device and computer program product

Patent metadata

Field	Value
Publication number	US-9958265-B2
Application number	US-201514816374-A
Country	US
Kind code	B2
Filing date	Aug 3, 2015
Priority date	Aug 5, 2014
Publication date	May 1, 2018
Grant date	May 1, 2018

Abstract

A specimen measuring device includes: a light source device that irradiates a specimen surface of a specimen with illumination light from multiple illumination units at a plurality of illumination angles; a spectral camera device that is arranged above the specimen surface, spectrally separates reflected light from the specimen surface, and acquires 2D spectral information through a single image capturing operation; and a calculating unit that calculates deflection angle spectral information of the specimen surface used to measure a measurement value of a certain evaluation item of the specimen using a change in an optical geometrical condition of an illumination direction and an image capturing direction between pixels in an X axis direction and a Y axis direction of the spectral information.

First claim

What is claimed is:

1. A specimen measuring device, comprising:
a light source device configured to irradiate a specimen surface of a specimen with illumination light from multiple illumination units at a plurality of illumination angles;
a spectral camera device arranged above the specimen surface, the spectral camera configured to spectrally separate reflected light from the specimen surface and to generate two-dimensional (2D) spectral information through a single image capturing operation; and
processing circuitry configured to calculate deflection angle spectral information of the specimen surface used to measure a measurement value of a certain evaluation item of the specimen using a change in an optical geometrical condition of an illumination direction and an image capturing direction between pixels in an X axis direction and a Y axis direction of the spectral information, wherein
the light source device changes at least one of a light quantity and an exposure time at a time of image capturing, and
the spectral camera device synthesizes a plurality of pieces of 2D spectral information acquired according to a change in a light quantity, an exposure time at a time of image capturing, or a light quantity and an exposure time at a time of image capturing by the light source device, and generates the 2D spectral information having an enlarged dynamic range.

2. The specimen measuring device according to claim 1 , wherein
the optical geometrical condition is at least one of a measurement range of the specimen surface, an angle of view of the spectral camera device, a distance between the specimen surface and one of the illumination units, a distance between the spectral camera device and the one of the illumination units, and the illumination angle of one of the illumination units, and
the one of the illumination units and the spectral camera device are arranged such that a deflection angle range to be measured is continuously acquired in the optical geometrical condition.

3. The specimen measuring device according to claim 1 , wherein the processing circuitry calculates a brightness histogram for each illumination angle and each spectral wavelength using the 2D spectral information acquired by the spectral camera device, and calculates a glittering area and glittering strength of each illumination angle and each spectral wavelength.

4. The specimen measuring device according to claim 1 , wherein the processing circuitry determines a rank of a diffusion light reflection angle excluding a regular reflection angle based on the 2D spectral information acquired by the spectral camera device, reconstructs an image using only pixels determined to be diffusion light other than regular-reflected light of an illumination of a particle image of each illumination angle, and calculates uniformity of an area of a bright portion and a dark portion as a graininess based on the reconstructed image using an entropy, variance or Fourier analysis of an image.

5. The specimen measuring device according to claim 1 , wherein the processing circuitry calculates a gloss value from a regular reflection angle, and calculates a haze value from the regular reflection angle and an adjacent angle using the deflection angle spectral information.

6. The specimen measuring device according to claim 1 , further comprising:
a projector that projects slit light of a certain pattern in an image capturing range of the spectral camera device, wherein
the processing circuitry measures measurement values of an image clarity and an orange peel of the specimen using the deflection angle spectral information generated by capturing an image of the slit light through the spectral camera device.

7. The specimen measuring device according to claim 6 , wherein
the projector projects an image of a white noise in the image capturing rage of the spectral camera device, and
the processing circuitry calculates the measurement value of the image clarity of the specimen using the deflection angle spectral information obtained by capturing an image of the white noise through the spectral camera device.

8. The specimen measuring device according to claim 1 , wherein the processing circuitry is further configured to
acquire three-dimensional (3D) information shape information of the specimen surface of the specimen,
calculate a normal line direction of each position of the specimen surface using the acquired 3D shape information of the specimen surface, and
correct the deflection angle spectral information acquired by the spectral camera device using the calculated normal line direction.

9. The specimen measuring device according to claim 1 , wherein the processing circuitry calculates measurement values of deflection angle color information, BRDF information, a glittering feeling, a graininess, a gloss, a haze, image clarity, and orange peel using the deflection angle spectral information.

10. The specimen measuring device according to claim 1 , wherein
the spectral camera device is a multi-band camera that that includes a main lens, a group of spectral filters, and a micro lens, and acquires spectral information according to number of the spectral filters, or a hyper spectral camera that includes one or more sets of filters and diffraction gratings or prisms, and
the spectral camera device acquires the 2D spectral information in synchronization with irradiation of illumination light of each illumination angle of the illumination unit through a single image capturing operation.

11. The specimen measuring device according to claim 10 , wherein the multi-band camera includes the group of spectral filters inserted into the main lens and a micro lens array inserted between the main lens and a light sensor, and acquires the spectral information according to the number of the spectral filters through each micro lens of the micro lens array.

12. The specimen measuring device according to claim 11 , wherein the multi-band camera acquires the spectral information according to the number of the spectral filters as the group of the spectral filters is installed between the micro lens array and the light sensor.

13. The specimen measuring device according to claim 1 , wherein the spectral camera device has an optical configuration in which each pixel is 10 μm to 1.011 μm of the specimen.

14. A non-transitory computer-readable medium storing executable instructions that, when executed by a computer, cause the computer to:
control a light source device to irradiate a specimen surface of a specimen with illumination light from multiple illumination units at a plurality of illumination angles;
control the light source device to change at least one of a light quantity and an exposure time at a time of image capturing:
control a spectral camera device arranged above the specimen surface to spectrally separate reflected light from the specimen surface and to generate two-dimensional (2D) spectral information through a single image capturing operation; and
calculate deflection angle spectral information of the specimen surface used to measure a measurement value of a certain evaluation item of the specimen using a change in an optical geometrical condition of an illumination direction and an image capturing direction between pixels in an X axis direction and a Y axis direction of the spectral information, wherein
the spectral camera device is controlled to synthesize a plurality of pieces of 2D spectral information acquired according to a change in a light quantity, an exposure time at a time of image capturing, or a light quantity and an exposure time at a time of image capturing by the light sou

Assignees

• Nagai Sho
• Masuda Kensuke
• Maruyama Go
• Yamanaka Yuji
• Kamijo Naohiro
• Kagitani Kenji
• Ricoh Co Ltd

Inventors

• Nagai Sho
• Masuda Kensuke
• Maruyama Go
• Yamanaka Yuji
• Kamijo Naohiro
• Kagitani Kenji

Classifications

• G01N2201/0635

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• G01N2021/1776

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• G01J3/504

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• G01N2021/4711

  Multiangle measurement · CPC title

• G01B11/306 Primary

  for measuring evenness · CPC title