Optical analysis system

• US 7,245,374 B2
• Filed: 11/21/2003
• Issued: 07/17/2007
• Est. Priority Date: 12/19/2002
• Status: Expired due to Fees

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Hendriks, Robert Frans Maria
• Primary Examiner(s): Nguyen; Tu T.
• Application Number:
  US10/539,193
• Publication Number:
  US 20060176471A1
• Time in Patent Office: 1,334 Days
• Field of Search: None
• US Class Current: 356/326
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0205 Optical elements not provided otherwise, e.g. optical manifolds, diffusers, windows
• CPC Class Codes: G01J 3/021 using plane or convex mirrors, parallel phase plates, or particular reflectors
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry
• CPC Class Codes: G01J 3/28 Investigating the spectrum using colour filters G01J3/51
• CPC Class Codes: G01J 3/36 Investigating two or more bands of a spectrum by separate detectors
• CPC Class Codes: G01N 2021/3196 Correlating located peaks in spectrum with reference data, e.g. fingerprint data
• CPC Class Codes: G01N 21/274 Calibration, base line adjustment, drift correction
• 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
• CPC Class Codes: G01N 2201/129 Using chemometrical methods

Abstract

An optical analysis system (1), which is arranged to determine amplitude of a principal component of an optical signal, includes a first detector (5) for detecting the optical signal weighted by a first spectral weighting function, and a second detector (6) for detecting the optical signal weighted by a second spectral weighting function. For an improved signal-to-noise ratio, the optical analysis system (1) further includes a dispersive element (2) for spectrally dispersing the optical signal, and a distribution element (4) for receiving the spectrally dispersed optical signal and for distributing a first part of the optical signal weighted by the first spectral weighting function to the first detector (5) and a second part of the optical signal weighted by the second spectral weighting function to the second detector (6). The optical analysis system (1) is suited for use in numerous applications including a spectroscopic analysis system (30) and a blood analysis system (40).

Claims

1. An optical analysis system for determining an amplitude of a principal component of an optical signal, the optical analysis system comprising:

a first detector for detecting the optical signal weighted by a first spectral weighting function,

a second detector for detecting the optical signal weighted by a second spectral weighting function,

a dispersive element for spectrally dispersing the optical signal, and

a distribution element for receiving the spectrally dispersed optical signal and for distributing a first part of the optical signal, weighted by the first spectral weighting function, to the first detector and a second part of the optical signal, weighted by the second spectral weighting function, to the second detector.

2. An optical analysis system as claimed in claim 1, wherein the principal component comprises a positive part in a first spectral range and a negative part in a second spectral range, the first part of the optical signal weighted by the first spectral weighting function corresponding to the positive part, the second part of the optical signal weighted by the second spectral weighting function corresponding to the negative part, the first detector and the second detector being coupled to a signal processor arranged to subtract a signal generated by the second detector from a signal generated by the first detector.

3. An optical analysis system as claimed in claim 1, wherein the principal component comprises a first principal component and a second principal component, the first part of the optical signal weighted by the first spectral weighting function corresponding to the first principal component, the second part of the optical signal weighted by the second spectral weighting function corresponding to the second principal component.

4. An optical analysis system as claimed in claim 1, wherein the distribution element has a surface for receiving the spectrally dispersed optical signal, the surface comprising a first set of surface elements and a second set of surface elements, the surface elements of the first set being arranged to distribute the spectrally dispersed optical signal to the first detector, the surface elements of the second set being arranged to distribute the spectrally dispersed optical signal to the second detector.

5. An optical analysis system as claimed in claim 1, wherein the distribution element comprises an array of liquid crystal elements arranged to form a first set of sub-arrays having refractive index gradients, and a second set of sub-arrays having refractive index gradients, the sub-arrays of the first set being arranged to distribute the spectrally dispersed optical signal to the first detector, the sub-arrays of the second set being arranged to distribute the spectrally dispersed optical signal to the second detector.

6. An optical analysis system as claimed in claim 1, wherein the dispersive element is arranged to disperse the optical signal in a dispersive plane and the optical analysis system further comprises a focusing member for focusing the dispersed optical signal, the focusing member having a first focal distance in the dispersive plane and a second focal distance in a plane perpendicular to the dispersive plane, the first focal distance being different from the second focal distance.

7. An optical analysis system as claimed in claim 6, further comprising a further focusing member for focusing the first part of the optical signal on the first detector.

8. An optical analysis system as claimed in claim 7, further comprising a further dispersive element for spectrally recombining the first part of the optical signal prior to focusing the first part on the first detector.

9. A spectroscopic analysis system comprising:

a light source for illuminating a sample, thereby generating an optical signal having a principal component with an amplitude, and

an optical analysis system for determining the amplitude of the principal component of the optical signal as claimed in claim 1.

10. A blood analysis system comprising a spectroscopic analysis system as claimed in claim 9.