Product inspection method and product inspection apparatus

Patent metadata

Field	Value
Publication number	US-12013347-B2
Application number	US-202017598401-A
Country	US
Kind code	B2
Filing date	Mar 25, 2020
Priority date	Mar 27, 2019
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

Super continuum light having a continuous spectrum over at least 1100 to 1300 nm is emitted from a pulsed light source, is pulse-stretched by a stretching element such that a relationship between a wavelength and an elapsed time in one pulse is one to one, and is radiated to a product. The light transmitted through the product is received by a light receiver, and output data is input to the determination unit. A quality determination program of the determination unit calculates an absorption spectrum from the output data, quantifies the absorption spectrum by chemometrics, and compares the absorption spectrum with a reference value to determine quality. The product determined to be a defective product is excluded by an exclusion mechanism.

First claim

The invention claimed is:

1. A product inspection method for determining quality of a product by performing light measurement, the method comprising:
an emission step of causing broadband pulsed light to be emitted from a light source;
a stretching step of stretching a pulse width of the emitted pulsed light by a stretching element such that a wavelength and an elapsed time have a one-to-one relationship in one pulse;
an irradiation step of irradiating a product with the stretched pulsed light;
a light receiving step of receiving, by a light receiver, light from the product irradiated with the stretched pulsed light; and
a determination step of determining quality of the product by processing output data from the light receiver.

2. The product inspection method according to claim 1 , wherein the determination step includes:
determining the quality of the product by calculating a content ratio or a content of a specific component of the product according to the output data; and
comparing the calculated content ratio or content with a reference value.

3. The product inspection method according to claim 1 , wherein the determination step includes:
determining the quality based on a value at a predetermined time in one pulse of the output data from the light receiver by comparison with a reference value without calculating an optical characteristic.

4. The product inspection method according to claim 1 , wherein the determination step includes:
determining the quality without performing quantitative determination by comparing an optical characteristic of a predetermined wavelength calculated based on a value at a predetermined time in one pulse of the output data from the light receiver or a value at the predetermined time with a reference value.

5. The product inspection method according to claim 1 , wherein the broadband pulsed light emitted in the emission step is light having a continuous spectrum covering at least a wavelength region of 1100 to 1200 nm.

6. The product inspection method according to claims 1 , wherein the broadband pulsed light emitted in the emission step is light having a continuous spectrum covering at least a wavelength region of 1000 to 1300 nm.

7. The product inspection method according to claims 1 , wherein the pulsed light pulse-stretched in the stretching step has a slope of a change in time with respect to a wavelength of 10 picoseconds or more per 1 nm.

8. The product inspection method according to claims 1 , wherein the light receiving step includes receiving light transmitted through the product.

9. The product inspection method according to claims 1 , wherein the irradiation step includes radiating the pulsed light in a pattern having a size equal to or larger than a size of the product from one side.

10. A product inspection apparatus structured to determine quality of a product by performing light measurement, the product inspection apparatus comprising:
a pulsed light source structured to emit broadband pulsed light;
a stretching element structured to stretch a pulse width of the pulsed light emitted from the pulsed light source such that a wavelength and an elapsed time in one pulse have a one-to- one relationship in one pulse;
a light receiver provided at a position where light from a product irradiated with the stretched pulsed light is received; and
a determination unit structured to determine quality of the product by processing output data from the light receiver.

11. The product inspection apparatus according to claim 10 , wherein the determination unit is structured to determine the quality of the product by calculating a content ratio or a content of a specific component of the product according to the output data from the light receiver and compare the calculated content ratio or content with a reference value.

12. The product inspection apparatus according to claim 10 , wherein the determination unit is structured to determine the quality based on a value at a predetermined time in one pulse of the output data from the light receiver by comparison with a reference value without calculating an optical characteristic.

13. The product inspection apparatus according to claim 10 , wherein the determination unit is structured to determine the quality without performing quantitative determination by comparing an optical characteristic of a predetermined wavelength calculated based on a value at a predetermined time in one pulse of the output data from the light receiver or a value at the predetermined time with a reference value.

14. The product inspection apparatus according to claims 10 , wherein the pulsed light source is structured to emit pulsed light that is light having a continuous spectrum covering at least a wavelength region of 1100 to 1200 nm.

15. The product inspection apparatus according to claims 10 , wherein the pulsed light source is structured to emit pulsed light that is light having a continuous spectrum covering at least a wavelength region of 1000 to 1300 nm.

16. The product inspection apparatus according to any one of claims 10 , wherein the stretching element is an element structured to perform pulse stretching in a state where a slope of a change in time with respect to a wavelength is 10 picoseconds or more per 1 nm.

17. The product inspection apparatus according to claims 10 , wherein the light receiver is provided at a position where light transmitted through the product is received.

18. The product inspection apparatus according to claims 10 , further comprising an exclusion mechanism structured to exclude a product determined to be a defective product.

19. The product inspection apparatus according to claims 10 , wherein the product is a tablet, and the product inspection apparatus further comprises an irradiation optical system structured to irradiate the tablet with the pulsed light pulse-stretched in a pattern having a size equal to or larger than a size of the tablet from one side.

Assignees

• Ushio Electric Inc
• Towa Pharmaceutical Co Ltd

Inventors

• Yamada Go
• Ota Aya
• Nakayama Koji

Classifications

• G01N2021/95615

  with stored comparision signal · CPC title

• G01N2021/8845

  Multiple wavelengths of illumination or detection · CPC title

• G01J3/42

  Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry (beam switching arrangements G01J3/08) · CPC title

• G01J11/00

  Measuring the characteristics of individual optical pulses or of optical pulse trains · CPC title

• G01N2021/396

  Type of laser source · CPC title