Imaging system, and method for specifying UV emission location using same

Patent metadata

Field	Value
Publication number	US-10914629-B2
Application number	US-201916577311-A
Country	US
Kind code	B2
Filing date	Sep 20, 2019
Priority date	Mar 21, 2017
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

An imaging system includes: an image sensor sensitive to ultraviolet light and visible light; a lens configured to focus light from a subject onto the image sensor; and an image processor configured to process image signals output from the image sensor. The image processor obtains the difference between image signals A 1 and A 2 output from the image sensor at times t1 and t2, respectively. If the differential signal A 3 is greater than or equal to a predetermined value, the image processor determines that light from the subject contains the ultraviolet light, and generates an image signal CI based on the differential signal A 3.

First claim

What is claimed is:

1. An imaging system comprising:
an image sensor sensitive to ultraviolet light and visible light;
a lens configured to focus light from a subject onto the image sensor; and
an image processor configured to process image signals output from the image sensor, wherein
the image processor
acquires a differential signal between an image signal output from the image sensor at a first time under illumination containing the visible light and an image signal output from the image sensor at a second time under illumination containing the visible light,
determines that the differential signal contains a signal associated with the emission of ultraviolet light if the differential signal is greater than or equal to a predetermined value, and
generates a first image signal based on the differential signal.

2. The imaging system of claim 1 , wherein
the image processor further generates a first composite image signal of the image signal output from the image sensor at the first time and the first image signal or an amplified first image signal.

3. The imaging system of claim 1 , further comprising:
a focus controller configured to control a position of the lens to adjust a focal length of the lens with respect to light with different wavelengths, wherein
the focus controller controls the position of the lens to match the focal length of the lens to the ultraviolet light at the first and second times, and controls the position of the lens to match the focal length of the lens to the visible light at a third time under illumination containing the visible light, and
the image processor further generates a second composite image signal of an image signal output from the image sensor at the third time and the first image signal or an amplified first image signal.

4. The imaging system of claim 2 , further comprising:
a display configured to display an image of the subject based on the first composite image signal.

5. The imaging system of claim 3 , further comprising:
a display configured to display an image of the subject based on the second composite image signal.

6. The imaging system of claim 1 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

7. The imaging system of claim 2 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

8. The imaging system of claim 3 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

9. The imaging system of claim 4 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

10. The imaging system of claim 5 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

11. A method of identifying a location emitting ultraviolet light using an imaging system including at least:
an image sensor sensitive to ultraviolet light and visible light;
a lens configured to focus light from a subject onto the image sensor; and
an image processor configured to process image signals output from the image sensor, the method comprising:
imaging a subject to acquire ones of the image signals at a first time under illumination containing the visible light and a second time under illumination of the visible light using the image sensor;
obtaining a differential signal between the ones of the image signals acquired at the first and second times using the image processor;
determining whether or not the differential signal is greater than or equal to a predetermined value using the image processor;
determining that the differential signal contains a signal associated with the ultraviolet light if the differential signal is greater than or equal to a predetermined value;
generating a first image signal based on the differential signal containing the signal associated with the emission of ultraviolet light using the image processor; and
identifying the location associated with the emission of the ultraviolet light in the subject using the image processor, based on the first image signal.

12. The method of claim 11 , wherein
the location emitting the ultraviolet light is identified in the subject using the image processor, based on a first composite image signal of the first image signal or an amplified first image signal and the one of the image signals acquired at the first time.

13. The method of claim 11 , further comprising:
adjusting a position of the lens to match a focal length of the lens to the ultraviolet light at the first and second times;
adjusting the position of the lens to match the focal length of the lens to the visible light at a third time under illumination containing the visible light; and
imaging the subject to acquire an image signal at the third time using the image sensor, wherein
the location of the emission of the ultraviolet light is identified in the subject using the image processor, based on a second composite image signal of the first image signal or an amplified first image signal and the image signal acquired at the third time.

14. The method claim 11 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

15. The method claim 12 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

16. The method claim 13 , wherein
the ultraviolet light has a wavelength within a range from 200 nm (inclusive) to 400 nm (exclusive), while the visible light has a wavelength within a range from 400 nm to 700 nm.

17. The imaging system of claim 1 , wherein
the imaging of the subject using the image sensor is continued if the differential signal is smaller than a predetermined value.

18. The method of claim 11 , further comprising:
determining, by the image processor, whether or not the differential signal is equal to or greater than the predetermined value, and continuing with the imaging of the subject using the image sensor if the differential signal is smaller than the predetermined value.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Okino Toru
• Hirose Yutaka
• Yamahira Seiji

Classifications

• G01J3/443

  Emission spectrometry · CPC title

• G01J1/0411

  using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction · CPC title

• G01J3/0237

  Adjustable, e.g. focussing · CPC title

• G01J1/4228

  arrangements with two or more detectors, e.g. for sensitivity compensation · CPC title

• G01J1/0448

  Adjustable, e.g. focussing · CPC title