Method and apparatus for radiation analysis and encoder

• US 7,330,253 B2
• Filed: 11/30/2005
• Issued: 02/12/2008
• Est. Priority Date: 06/26/1998
• Status: Expired due to Fees

• Current Assignee: Mudlogging Systems Inc. (ALS Oil & Gas)
• Original Assignee: Aspectrics
• Inventors: Hagler, Thomas W.
• Primary Examiner(s): Lauchman; Layla G.
• Application Number:
  US11/291,179
• Publication Number:
  US 20060132763A1
• Time in Patent Office: 804 Days
• Field of Search: 356/310, 356/323, 356/326, 356/330, 359/236, 359/238, 250/226
• US Class Current: 356/310
• CPC Class Codes: G01J 2001/4242 Modulated light, e.g. for synchronizing source and detector circuit
• CPC Class Codes: G01J 2003/2866 Markers; Calibrating of scan
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/021 using plane or convex mirrors, parallel phase plates, or particular reflectors
• CPC Class Codes: G01J 3/0229 using masks, aperture plates, spatial light modulators or spatial filters, e.g. reflective filters
• CPC Class Codes: G01J 3/12 Generating the spectrum; Monochromators
• CPC Class Codes: G01J 3/2846 using modulation grid; Grid spectrometers
• CPC Class Codes: G01J 3/32 Investigating bands of a spectrum in sequence by a single detector
• CPC Class Codes: G01J 3/433 Modulation spectrometry; Derivative spectrometry
• CPC Class Codes: G01N 2021/6417 Spectrofluorimetric devices
• CPC Class Codes: G01N 2021/6423 Spectral mapping, video display
• CPC Class Codes: G01N 2021/6463 Optics
• CPC Class Codes: G01N 2021/6471 Special filters, filter wheel
• CPC Class Codes: G01N 21/6456 Spatial resolved fluorescence measurements; Imaging

Abstract

Method and apparatus for analyzing radiation using analyzers and encoders employing the spatial modulation of radiation dispersed by wavelength or imaged along a line.

Claims

1. A system for analyzing one or more components of an incident radiation beam, the system comprising:

first optics configured to focus the radiation beam to form an image in an encoding plane for each of one or more components of the beam;

a spatial radiation modulator comprising a substrate and at least one radiation filter located on the substrate, wherein the modulator is adapted to encode the components of the radiation beam when the radiation beam and the modulator are moved relative to one another according to a relative motion that comprises a substantially repeating motion substantially having a period of repetition;

a detector configured to provide a signal based on a received radiation beam;

second optics configured to direct the encoded radiation beam onto the detector; and

a processor configured to analyze a signal generated by the detector in response to the encoded radiation beam.

2. The system of claim 1, wherein the radiation filter comprises an area substantially encompassing a plurality of pixels having optical characteristics substantially different from the substrate.

3. The system of claim 2, wherein the pixels are patterned substantially within the area to modulate the intensity of a corresponding component substantially only along the direction of the relative motion to provide an encoded component, wherein the amplitude of the encoded component changes between three or more substantially distinct levels of contrast over the period of repetition.

4. The system of claim 1, wherein the radiation filter comprises an area substantially encompassing a first number of non-contiguous regions having optical characteristics substantially different from the substrate.

5. The system of claim 4, wherein the non-contiguous regions are patterned substantially within the area to modulate the intensity of a corresponding component as a halftone representation of a substantially smooth function having a second number of local maxima over the period of repetition, wherein the first number of non-contiguous regions is greater than the second number of local maxima.

6. A method for analyzing an incident radiation beam, the method comprising:

focusing one or more components of the incident radiation beam to form a corresponding image of the components;

moving a spatial radiation modulator relative to the radiation beam according to a relative motion that comprises a substantially repeating motion substantially having a period of repetition, wherein the modulator is adapted to encode separately the components of the radiation beam in response to the relative motion;

directing the encoded radiation beam onto a detector, the detector configured to provide a signal based on the encoded radiation beam;

analyzing the signal generated by the detector; and

outputting the signal to a storage medium.

7. The method of claim 6, wherein the spatial radiation modulator comprises a substrate and at least one radiation filter located on the substrate.

8. The method of claim 7, wherein the radiation filter comprises an area substantially encompassing a plurality of pixels having optical characteristics substantially different from the substrate.

9. The method of claim 8, wherein the pixels are patterned substantially within the area to modulate the intensity of a corresponding component substantially only along the direction of the relative motion to provide an encoded component, wherein the amplitude of the encoded component changes between three or more substantially distinct levels of contrast over the period of repetition.

10. The method of claim 7, wherein the radiation filter comprises an area substantially encompassing a first number of non-contiguous regions having optical characteristics substantially different from the substrate.

11. The method of claim 10, wherein the non-contiguous regions are patterned substantially within the area to modulate the intensity of a corresponding component as a halftone representation of a substantially smooth function having a second number of local maxima over the period of repetition, wherein the first number of non-contiguous regions is greater than the second number of local maxima.

12. A spatial radiation modulator for modulating at least one component of an incident radiation beam, the modulator comprising a substrate and at least one radiation filter located on the substrate, wherein the modulator is adapted to encode an incident radiation beam when the radiation beam and the modulator are moved relative to one another according to a relative motion that comprises a substantially repeating motion substantially having a period of repetition, and wherein the radiation filter comprises an area substantially encompassing a plurality of pixels having optical characteristics substantially different from the substrate.

13. The spatial radiation modulator of claim 12, wherein the pixels are patterned substantially within the area to modulate the intensity of a corresponding component substantially only along the direction of the relative motion to provide an encoded component, wherein the amplitude of the encoded component changes between three or more substantially distinct levels of contrast over the period of repetition.

14. The spatial radiation modulator of claim 12, wherein the radiation filter comprises an area substantially encompassing a first number of non-contiguous regions having optical characteristics substantially different from the substrate.

15. The spatial radiation modulator of claim 14, wherein the non-contiguous regions are patterned substantially within the area to modulate the intensity of a corresponding component as a halftone representation of a substantially smooth function having a second number of local maxima over the period of repetition, wherein the first number of non-contiguous regions is greater than the second number of local maxima.

16. A method for analyzing an incident radiation beam, the method comprising:

focusing one or more spectral components of the incident radiation beam to form an image characteristic of the spectral components;

moving a spatial radiation modulator relative to the radiation beam according to a relative motion that comprises a substantially repeating motion substantially having a period of repetition, wherein the modulator is adapted to encode separately the spectral components of the radiation beam in response to the relative motion;

directing the encoded radiation beam onto a detector, the detector configured to provide a signal based on the encoded radiation beam;

analyzing the signal generated by the detector to determine the spectral components; and

outputting a wavelength corresponding to each of the one or more spectral components of the signal to a storage medium.

17. The method of claim 16, wherein the modulator comprises a substrate and at least one radiation filter located on the substrate, and wherein amplitudes of the encoded spectral components change between three or more substantially distinct levels of contrast over the period of repetition.