Apparatus and method for measuring a concentration of a component of a target material

• US 6,625,480 B2
• Filed: 04/24/2002
• Issued: 09/23/2003
• Est. Priority Date: 05/09/2001
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Yoon, Gil-won, Hwang, In-duk
• Primary Examiner(s): WINAKUR, ERIC FRANK
• Application Number:
  US10/128,338
• Publication Number:
  US 20020169368A1
• Time in Patent Office: 517 Days
• Field of Search: 600/310, 600/316, 600/322, 600/476, 356/300, 356/301, 356/319, 356/320, 356/326, 356/328, 422/82.05, 422/82.09
• US Class Current: 600/310
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: G01J 3/42 Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• 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

Abstract

Apparatus and method for measuring concentration of a component of target material including a pumping light source for emitting light; a first wavelength conversion unit for converting and outputting the light; a first beam splitting unit for splitting the converted light and directing a first light beam at the target material; a reference light generator for converting a second light beam to be parallel, dividing the parallel light beam by wavelengths, and outputting the result as reference light; a first collimating unit for converting light transmitted through the target material to be parallel and outputting the parallel light; a light intensity measuring unit for measuring the intensity of light from the first collimating unit and the reference light, by wavelengths, using the reference light; and a concentration measuring unit for measuring the concentration of the component based on the intensities measured by the light intensity measuring unit by wavelengths.

Claims

1. An apparatus for measuring a concentration of a component of a target material, the apparatus comprising:

a pumping light source for emitting light having a single wavelength having peak power of at least a predetermined value;

a first wavelength conversion unit for converting light incident from the pumping light source into light having at least one discrete wavelength and outputting the converted light;

a first beam splitting unit for splitting the converted light incident from the first wavelength conversion unit into light beams and directing a first light beam at the target material;

a reference light generator for converting a second light beam generated by the splitting performed in the first beam splitting unit to be parallel, dividing the parallel light beam by wavelengths, and outputting the result of the division as reference light;

a first collimating unit for converting light transmitted through the target material to be parallel and outputting the parallel light;

a light intensity measuring unit for measuring the intensity of light incident from the first collimating unit and the intensity of the reference light, by wavelengths, using the reference light; and

a concentration measuring unit for measuring the concentration of the component based on the intensities measured by the light intensity measuring unit by wavelengths.

2. The apparatus as claimed in claim 1, wherein the concentration measuring unit comprises:

an amplifier for amplifying the intensity measured by the light intensity measuring unit by wavelengths and outputting the result of the amplification;

an analog-to-digital converter (ADC) for converting the result of the amplification into a digital signal and outputting the digital signal; and

a signal processor for analyzing the digital signal to measure the concentration of the component of the target material.

3. The apparatus as claimed in claim 1, further comprising a first condensing lens for condensing the first light beam generated by the splitting performed in the first beam splitting unit and transmitting the result of the condensing at the target material.

4. The apparatus as claimed in claim 1, further comprising an index-matching unit for transmitting the first one of the light beams generated by the splitting performed in the first beam splitting unit at the target material.

5. The apparatus as claimed in claim 1, further comprising a wavelength divider for dividing light incident from the first collimating unit by wavelengths and outputting the result of the division to the light intensity measuring unit, wherein the light intensity measuring unit measures the intensity of light incident from the wavelength divider and the intensity of the reference light, by wavelengths.

6. The apparatus as claimed in claim 1, wherein the first wavelength conversion unit comprises a first through Y-th wavelength converters, wherein Y is 1 or a positive integer greater than 1, connected in series, and the y-th, wherein 1≦

y≦

Y, wavelength converter condenses incident light and converts the incident light into light having at least one wavelength and converts the light having at least one wavelength to be output in parallel.

7. The apparatus as claimed in claim 6, wherein the y-th wavelength converter comprises:

a light condensing unit for condensing incident light and outputting the condensed light;

an optical fiber for receiving the condensed light from the light condensing unit and outputting the light having at least one wavelength; and

a second collimating unit for converting the light received from the optical fiber to be parallel and outputting the converted light.

8. The apparatus as claimed in claim 7, wherein the light condensing unit comprises a second condensing lens for condensing the incident light and outputting the condensed light to an incident surface of a core of the optical fiber.

9. The apparatus as claimed in claim 7, wherein the light condensing unit comprises tapered fiber for condensing the incident light and outputting the condensed light to an incident surface of a core of the optical fiber.

10. The apparatus as claimed in claim 9, wherein the tapered fiber is fusion-spliced to the optical fiber.

11. The apparatus as claimed in claim 7, wherein a core of the optical fiber is made of pure silica.

12. The apparatus as claimed in claim 7, wherein a core of the optical fiber is doped with GeO₂.

13. The apparatus as claimed in claim 7, wherein a core of the optical fiber is doped with P₂O₅.

14. The apparatus as claimed in claim 7, wherein the optical fiber is a single mode optical fiber.

15. The apparatus as claimed in claim 7, wherein the optical fiber is a multi-mode optical fiber.

16. The apparatus as claimed in claim 7, wherein the optical fiber is a step-index optical fiber.

17. The apparatus as claimed in claim 7, wherein the optical fiber is a graded-index optical fiber.

18. The apparatus as claimed in claim 1, wherein the target material is selected from a group consisting of a living body, an organism and a sample cuvette.

19. The apparatus as claimed in claim 1, wherein the pumping light source is selected from a group consisting of a pulse laser and a continuous wave (CW) laser.

20. The apparatus as claimed in claim 19, wherein the pulse laser is one selected from the group consisting of a Nd:

YAG laser, a Ho;

YAG laser, a Tm;

YAG laser, an optical parametric oscillation (OPO) laser, a solid-state laser, and an optical fiber laser.

21. The apparatus as claimed in claim 1, wherein the light intensity measuring unit comprises a near infrared light intensity measuring unit for measuring the intensity of light incident from the first collimating unit and the intensity of the reference light, by wavelengths.

22. The apparatus as claimed in claim 1, wherein the light intensity measuring unit comprises an array light intensity measuring unit for measuring the intensity of light incident from the first collimating unit and the intensity of the reference light, by wavelengths.

23. An apparatus for measuring a concentration of a component of a target material, the apparatus comprising:

a pumping light source for emitting light having a single wavelength having peak power of at least a predetermined value;

a second through 2V-th beam splitting units, wherein V is at least 2;

a second through (V+1)-th wavelength conversion units;

a total reflector;

a reference light generator for converting a light beam generated by splitting performed in each of the (V+1)-th through the 2V-th beam splitting units to be parallel, dividing the parallel light by wavelengths, and outputting the result of the division as reference light;

a first collimating unit for converting light transmitted through the target material to be parallel and outputting the parallel light;

a light intensity measuring unit for measuring the intensity of light incident from the first collimating unit and the intensity of the reference light, by wavelengths, using the reference light; and

a concentration measuring unit for measuring the concentration of the component based on the intensities measured by the light intensity measuring unit by wavelengths,

wherein the second beam splitting unit splits light incident from the pumping light source into light beams and outputs one of the light beams to the second wavelength conversion unit, the v-th (3≦

v≦

V) beam splitting unit receives and splits one of light beams generated by the splitting performed in the (v−

1)-th beam splitting unit into light beams and outputs one of the light beams to a v-th wavelength conversion unit, the total reflector totally reflects one of the light beams generated by the splitting performed in the V-th beam splitting unit to the (V+1)-th wavelength conversion unit, the w-th (2≦

w≦

V+1) wavelength conversion unit converts incident light into light having at least one discrete wavelength and outputs the converted light, and the (V+w−

1)-th beam splitting unit splits light incident from the w-th wavelength conversion unit into light beams and outputs one of the light beams at the target material.

24. The apparatus as claimed in claim 23, wherein the concentration measuring unit comprises:

an amplifier for amplifying the intensity measured by the light intensity measuring unit by wavelengths and outputting the result of the amplification;

an analog-to-digital converter (ADC) for converting the result of the amplification into a digital signal and outputting the digital signal; and

a signal processor for analyzing the digital signal to measure the concentration of the component of the target material.

25. The apparatus as claimed in claim 23, further comprising a first condensing lens for condensing one of the light beams generated by the splitting performed in the x-th beam splitting unit, wherein x is between V+1 and 2V inclusive, and transmitting the result of the condensing at the target material.

26. The apparatus as claimed in claim 23, further comprising an index-matching unit for transmitting one of the light beams generated by splitting performed in the x-th beam splitting unit, wherein x is between V+1 and 2V inclusive, at the target material.

27. The apparatus as claimed in claim 23, further comprising a wavelength divider for dividing light incident from the first collimating unit by wavelengths and outputting the result of the division to the light intensity measuring unit, wherein the light intensity measuring unit measures the intensity of light incident from the wavelength divider and the intensity of the reference light, by wavelengths.

28. The apparatus as claimed in claim 23, wherein each of the second through (V+1)-th wavelength conversion units comprises a first through Y-th wavelength converters, wherein Y is 1 or a positive integer greater than 1, connected in series, and the y-th, wherein 1≦

y≦

Y, wavelength converter condenses incident light and converts the incident light into light having at least one wavelength and converts the light having at least one wavelength to be output in parallel.

29. The apparatus as claimed in claim 28, wherein the y-th wavelength converter comprises:

a light condensing unit for condensing incident light and outputting the condensed light;

an optical fiber for receiving the condensed light from the light condensing unit and outputting the light having at least one wavelength; and

a second collimating unit for converting the light received from the optical fiber to be parallel and outputting the converted light.

30. The apparatus as claimed in claim 29, wherein the light condensing unit comprises a second condensing lens for condensing the incident light and outputting the condensed light to an incident surface of a core of the optical fiber.

31. The apparatus as claimed in claim 29, wherein the light condensing unit comprises tapered fiber for condensing the incident light and outputting the condensed light to an incident surface of a core of the optical fiber.

32. The apparatus as claimed in claim 31, wherein the tapered fiber is fusion-spliced to the optical fiber.

33. The apparatus as claimed in claim 29, wherein a core of the optical fiber is made of pure silica.

34. The apparatus as claimed in claim 29, wherein a core of the optical fiber is doped with GeO₂.

35. The apparatus as claimed in claim 29, wherein a core of the optical fiber is doped with P₂O₅.

36. The apparatus as claimed in claim 29, wherein the optical fiber is a single mode optical fiber.

37. The apparatus as claimed in claim 29, wherein the optical fiber is a multi-mode optical fiber.

38. The apparatus as claimed in claim 29, wherein the optical fiber is a step-index optical fiber.

39. The apparatus as claimed in claim 29, wherein the optical fiber is a graded-index optical fiber.

40. The apparatus as claimed in claim 23, wherein the target material is selected from a group consisting of a living body, an organism and a sample cuvette.

41. The apparatus as claimed in claim 23, wherein the pumping light source is selected from a group consisting of a pulse laser and a continuous wave (CW) laser.

42. The apparatus as claimed in claim 41, wherein the pulse laser is one selected from the group consisting of a Nd:

YAG laser, a Ho;

YAG laser, a Tm;

YAG laser, an optical parametric oscillation (OPO) laser, a solid-state laser, and an optical fiber laser.

43. The apparatus as claimed in claim 23, wherein the light intensity measuring unit comprises a near infrared light intensity measuring unit for measuring the intensity of light incident from the first collimating unit and the intensity of the reference light, by wavelengths.

44. The apparatus as claimed in claim 23, wherein the light intensity measuring unit comprises an array light intensity measuring unit for measuring the intensity of light incident from the first collimating unit and the intensity of the reference light, by wavelengths.

45. A method for measuring a concentration of a component of a target material, the method comprising:

(a) emitting light having a single wavelength having peak power of at least a predetermined value;

(b) converting the emitted light into light having at least one discrete wavelength;

(c) splitting the converted light into light beams, directing a first light beam at the target material, converting a second light beam to be parallel, and dividing the parallel converted second light beam by wavelengths to generate reference light;

(d) converting light transmitted through the target material to be parallel;

(e) measuring the intensity of the parallel converted light obtained in (d) and the intensity of the reference light, by wavelengths; and

(f) measuring the concentration of the component based on the intensities measured by wavelengths.

46. The method as claimed in claim 45, further comprising:

(g) splitting the light emitted in (a) into at least two light beams,

wherein (b) comprises converting each of the at least two light beams obtained in (g) into light having at least one wavelength, and (c) comprises splitting the converted light obtained in (b) into light beams, radiating a first one of the light beams at the target material, converting a second one of the light beams to be parallel, and dividing the parallel converted second light beam by wavelengths to generate the reference light.

47. The method as claimed in claim 45, wherein (f) comprises:

amplifying the intensities measured by wavelengths in (e);

converting the result of amplification into a digital form to generate a digital signal; and

analyzing the digital signal to measure the concentration of the component of the target material.

48. The method as claimed in claim 45, further comprising condensing the first one of the light beams obtained in (c) and transmitting the result of condensing at the target material.