Miniature Fourier Transform Spectrometer and Method of Operation

• US 20100284017A1
• Filed: 12/28/2007
• Published: 11/11/2010
• Est. Priority Date: 11/14/2007
• Status: Active Grant

• Current Assignee: Block Engineering, LLC
• Original Assignee: Block Engineering, LLC
• Inventors: Kim, Jinhong, Schildkraut, E. Robert, Reyes, David
• Granted Patent: US 8,587,787 B2
• Time in Patent Office: Days
• US Class Current: 356/452
• CPC Class Codes: G01B 9/02051 Integrated design, e.g. on-chip or monolithic
• CPC Class Codes: G01J 3/4535 Devices with moving mirror G01J3/4532 takes precedence
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

A Micro-Electro-Mechanical Systems (MEMS) interferometer is implemented in a Fourier transform spectrometer, which includes a common housing containing the interferometer and a gas cell, possibly including a preconcentrator. The interferometer system includes an optical bench and at least two mirror structures, being patterned from one or more layers on the optical bench and erected to extend substantially perpendicularly to the bench to define two interferometer arms to provide a MEMS interferometer.

Claims

1. A spectroscopy system, comprising:

a housing being smaller than 100 millimeters cubed;

a light source for generating an optical signal to illuminate a species; and

an optical bench in the housing for processing the optical signal illuminating the species and dividing the optical signal between two interferometer arms and detecting interference of the optical signal from the two arms.

2. A system as claimed in claim 1, further comprising a sample cell defined by mirrors in the housing for containing the species to be illuminated.

3. A system as claimed in claim 2, further comprising a preconcentrator for absorbing gas species of interest and adsorbing the gas species into the sample cell.

4. A system as claimed in claim 1, wherein the housing is less than 200 millimeters long and has a diameter of less than 20 millimeters.

5. A system as claimed in claim 1, further comprising an attenuated total reflection cell for containing the species.

6. A system as claimed in claim 1, wherein the light source is installed on the bench.

7. A system as claimed in claim 1, further comprising a detector installed on the bench.

8. A system as claimed in claim 7, wherein the light source is installed on the bench with the detector.

9. A system as claimed in claim 1, further comprising a temperature controller for controlling a temperature of the optical bench.

10. A system as claimed in claim 1, further comprising a thermoelectric cooler for controlling a temperature of the optical bench.

11. A spectroscopy method, comprising:

exposing a cell to species of interest;

illuminating the species of interest in the gas cell with an optical signal;

processing the optical signal between two interferometer arms defined by mirror structures formed on an optical bench;

driving a mirror actuator formed on the optical bench that moves one of the mirror structures on the optical bench.

12. A method as claimed in claim 11, further comprising defining the cell with mirrors.

13. A method as claimed in claim 12, further comprising housing the gas cell and the optical bench within a common housing.

14. A method as claimed in claim 13, wherein the common housing is less than 100 millimeters cubed in volume.

15. A method as claimed in claim 13, wherein the housing is less than 200 millimeters long and has a diameter of less than 20 millimeters.

16. A method as claimed in claim 11, further comprising:

concentrating the species of interest; and

then releasing the concentrated species into the gas cell.

17. A method as claimed in claim 11, further comprising containing the species in an attenuated total reflection cell.

18. A method as claimed in claim 11, further comprising installing a source generating the optical signal on the optical bench.

19. A method as claimed in claim 11, further comprising installing a detector for the optical signal on the optical bench.

20. A method as claimed in claim 11, further comprising installing a detector for the optical signal on the optical bench with a light source generating the optical signal on the optical bench.

21. A method as claimed in claim 11, further comprising controlling a temperature of the optical bench.

22. A spectroscopy system, comprising:

a light source for generating an optical signal to illuminate a species; and

a microelectromechanical systems optical bench including two interferometer arms for processing the optical signal illuminating the species by dividing the optical signal between the two interferometer arms and detecting interference of the optical signal from the two arms.

23. A system as claimed in claim 22, further comprising a sample cell defined by mirrors in the housing for containing the species to be illuminated.

24. A system as claimed in claim 23, further comprising a preconcentrator for absorbing gas species of interest and adsorbing the gas species into the sample cell.

25. A system as claimed in claim 22, further comprising an attenuated total reflection cell for containing the species.

26. A system as claimed in claim 22, further comprising a detector installed on the bench.

27. A system as claimed in claim 22, further comprising a temperature controller for controlling a temperature of the optical bench.