Optical emission system including dichroic beam combiner

• US 9,752,933 B2
• Filed: 02/04/2015
• Issued: 09/05/2017
• Est. Priority Date: 04/30/2012
• Status: Active Grant

• Current Assignee: Agilent Technologies, Inc.
• Original Assignee: Agilent Technologies, Inc.
• Inventors: Bolles, Michael, Sun, Yin Sheng, Buck, Lindsay, Russell, Glyn
• Primary Examiner(s): Lyons, Michael A
• Application Number:
  US14/614,381
• Publication Number:
  US 20150138548A1
• Time in Patent Office: 944 Days
• CPC Class Codes: G01J 2003/1217 Indexed discrete filters or choppers
• CPC Class Codes: G01J 3/0205 Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows
• CPC Class Codes: G01J 3/0208 using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry
• CPC Class Codes: G01J 3/12 Generating the spectrum; Monochromators
• CPC Class Codes: G01J 3/443 Emission spectrometry

Abstract

An optical emission spectrometer system includes a light source and a dichroic beam combiner. The light source emits first light in a first direction and second light in a second direction different from the first direction. The dichroic beam combiner receives the first light via a first light path and the second light via a second light path, reflects a portion the first light into an entrance aperture of a light detection and measurement apparatus, and transmits a portion of the second light into the entrance aperture, enabling analysis and measurement of both first and second light characteristics simultaneously. The portion of the first light reflected into the entrance aperture predominately has wavelengths in a first range of wavelengths and the portion of the second light transmitted into the entrance aperture predominately has wavelengths in a second range of wavelengths, different from the first range of wavelengths.

Claims

1. An optical emission spectrometer system, comprising:

a light source configured to emit first light in a first direction and second light in a second direction different from the first direction;

a dichroic beam combiner configured to receive the first light via a first light path and the second light via a second light path, to reflect a portion of the first light into an entrance aperture of a light detection and measurement apparatus, and to transmit a portion of the second light into the entrance aperture, wherein the portion of the first light reflected into the entrance aperture predominately has wavelengths in a first range of wavelengths and the portion of the second light transmitted into the entrance aperture predominately has wavelengths in a second range of wavelengths different from the first range of wavelengths; and

a movable member including the dichroic beam combiner, a mirrored section and a transparent section, the movable member being operable to place one of the dichroic beam combiner, the mirrored section and the transparent section into the first and second light paths for receiving the first and second light.

2. The system of claim 1, wherein the mirrored section of the movable member is configured to reflect substantially all wavelengths of the first light into the entrance aperture of the detector, and to reflect substantially all wavelengths of the second light away from the entrance aperture of the detector.

3. The system of claim 1, wherein the transparent section of the movable member is configured to transmit substantially all wavelengths of the first light away from the entrance aperture of the detector, and to transmit substantially all wavelengths of the second light into the entrance aperture of the detector.

4. The system of claim 1, wherein the first direction is along art axis of the light source and the second direction is substantially perpendicular to the axis of the light source.

5. The system of claim 1, wherein the first range of wavelengths is below a predetermined wavelength value, and the second range of wavelengths is above the predetermined wavelength value.

6. The system of claim 5, wherein the predetermined wavelength value is about 500 nm.

7. The system of claim 1, wherein the first range of wavelengths is above a predetermined wavelength value, and the second range of wavelengths is below the predetermined wavelength value.

8. The system of claim 7, wherein the predetermined wavelength value is about 500 nm.

9. The system of claim 1, wherein the first light path comprises a first set of mirrors configured to direct the first light to the dichroic beam combiner;

and

wherein the second light path comprises a second set of mirrors configured to direct the second light to the dichroic beam combiner.

10. The system of claim 1, wherein the light detection and measurement apparatus comprises one of a monochromator or a polychromator, and at least one associated light detector.

11. An optical emission spectrometer system, comprising:

a light source configured to emit first light in a first direction and second light in a second direction different from the first direction; and

a dichroic beam combiner configured to receive the first light via a first light path and the second light via a second light path, to reflect a portion of the first light into an entrance aperture of a light detection and measurement apparatus, and to transmit a portion of the second light into the entrance aperture,

wherein the portion of the first light reflected into the entrance aperture predominately has wavelengths in a first range of wavelengths and the portion of the second light transmitted into the entrance aperture predominately has wavelengths in a second range of wavelengths different from the first range of wavelengths, and

wherein the light source comprises an inductively coupled plasma light source.

12. The system of claim 11, wherein the first direction is along an axis of the light source and the second direction is substantially perpendicular to the axis of the light source.

13. The system of claim 11, wherein the first light path comprises a first set of mirrors configured to direct the first light to the dichroic beam combiner;

and

wherein the second light path comprises a second set of mirrors configured to direct the second light to the dichroic beam combiner.

14. An optical emission spectrometer apparatus, comprising:

optical directing means configured to direct first light emitted from a light source in a first direction along a first light path to a single light detection and measurement apparatus, and to direct second light emitted from the light source in a second direction, different from the first direction, along a second light path to the same light detection and measurement apparatus;

optical filtering means configured to simultaneously filter the first and second light into predominantly different wavelength ranges;

optical combining means to combine the filtered first and second light prior to the single lioht detection and measuremc apparatus; and

a movable member selectively movable among first, second and third positions corresponding to the optical filtering means, a mirrored section and a transparent section, respectively, wherein operation of the movable member places one of the optical filtering means, the mirror section and the transparent section into the first and second light paths for receiving the first and second light.

15. The apparatus of claim 14, wherein the mirror section is configured to reflect substantially all wavelengths of only one of the first and second light into the entrance aperture when the movable member is in the second position, and

wherein the transparent section is configured to transmit substantially all wavelengths of only one of the first and second light into the entrance aperture when the movable member is in the third position.

16. The system of claim 14, wherein the light detection and measurement apparatus comprises one of a monochromator or a polychromator, and at least one associated light detector.

17. The apparatus according to claim 14, wherein at least one of the optical filtering means and the optical combining means comprises a dichroic beam combiner configured to reflect a portion of the first light having wavelengths below a predetermined value and to transmit a portion of the second light having wavelengths above the nominal value into the entrance aperture.

18. The apparatus according to claim 14, wherein at least one of the optical filtering means and the optical combining means comprises a dichroic beam combiner configured to transmit a portion of the first light having wavelengths below a nominal value and to reflect a portion of the second light having wavelengths above the nominal value into the entrance aperture.

19. An optical emission spectrometer system, comprising:

a plasma light source configured to emit first light in a first direction and second light in a second direction substantially perpendicular to the first direction;

a first plurality of mirrors for directing the first light along a first light path;

a second plurality of mirrors for directing the second light along a second light path; and

a mode selector comprising a plurality of mode sections corresponding to a plurality of positions of the mode selector, the mode selector being selectively movable such that the first and second light paths intersect one of the plurality of mode sections, the plurality of mode sections comprising;

a dichroic beam combiner configured to reflect wavelengths of the first light predominantly in a predetermined first wavelength range into an entrance aperture of a detector, and to transmit wavelengths of the second light predominantly in a predetermined second wavelength range into the entrance aperture, enabling analysis of both the first light and the second light, the second wavelength range being different from the first wavelength range;

a mirrored section configured to reflect all wavelengths of the first light into the entrance aperture of the detector, and to reflect all wavelengths of the second light away from the entrance aperture of the detector, enabling analysis of the first light; and

a transparent section configured to transmit all wavelengths of the second light into the entrance aperture of the detector, and to transmit all wavelengths of the first light away from the entrance aperture of the detector, enabling analysis of the second light.

20. The system of claim 19, wherein the first wavelength range comprises wavelengths below a predetermined, wavelength value and the second wavelength range comprises wavelengths above the predetermined wavelength value.