Integrated sensing system approach for handheld spectral measurements having a disposable sample handling apparatus
An integrated spectral sensing engine featuring energy sources and detectors within a single package that includes sample interfacing optics and acquisition and processing electronics. The miniaturized sensor is optimized for specific laboratory and field-based measurements by integration into a handheld format. Design and fabrication components support high volume manufacturing. Spectral selectivity is provided by either continuous variable optical filters or filter matrix devices. The sensor's response covers the range from 200 nm to 25 μm based on various solid-state detectors. The wavelength range can be extended by the use of filter-matrix devices. Measurement modes include transmittance/absorbance, turbidity (light scattering) and fluorescence (emission). On board data processing includes raw data acquisition, data massaging and the output of computed results. Sensor applications include water and environmental, food and beverage, chemical and petroleum, and medical analyses. These can be expanded into various field and consumer-based applications.
1. An optical spectral sensing device, for determining properties of a sample, said device comprising:
an integrated energy source and an integrated spectral sensing detector package having a spectral sensing detector;
a sample chamber or cell, disposed adjacent to said package, and dimensionally designed to match an active area of the spectral sensing detector;
integrated electronics coupled to said package for providing energy for said source and for receiving a signal generated by said spectral sensing detector in response to energy coupled to said detector by said sample chamber or cell, said integrated electronics providing direct output of sample properties of said sample;
said integrated electronics having on-board computer processing with a microcomputer or digital signal processor;
said integrated electronics having on-board data communications including output to at least one of a visual display, communications of results to a process monitoring computer, and an option for wireless communications to a network; and
a sample handling apparatus for disposable sample handling, said apparatus being releasably attached adjacent said package, said sample handling apparatus forming at least a part of said sample chamber or cell to contain said sample, said sample handling apparatus containing an optical path from said energy source to said spectral sensing detector.
2. The device of claim 1 , wherein said sampling apparatus has an optical structure formed in a configuration that allow for at least one of transflectance, transmittance/absorption, fluorescence or light scattering measurements.
3. The device of claim 1 , wherein said sample handling apparatus comprises an optical structure fabricated from at least one of glass, plastic, metal and similar materials that can be machined or molded to provide a sample interface with a cross-section that has optimal coupling between the energy source and the spectral sensing detector.
4. The device of claim 1 , wherein said spectral sensing detector comprises an integrated spectral measurement system based on the use of a continuous linear variable filter (LVF) or discrete optical components that comprise a matrix or mosaic-based filter-detector measurement system.
5. The device of claim 1 , wherein said sample handling apparatus is disposable.
6. The device of claim 5 , wherein the sample handling apparatus is configured to have an optical transmission/absorption mode where energy passes into the sample, traverses the sample into a retro-reflective optical structure, re-enters the sample, and is imaged on to the spectral sensing detector.
7. The device of claim 5 , wherein said sample handling apparatus is configured to have an optical scattering mode or fluorescence/emission mode, wherein energy propagates orthogonally with respect to normal passage of energy through the sample.
8. The device of claim 1 , further comprising a sample interface component disposed between said device and said sample handling apparatus that is renewable and disposable.
9. The device of claim 1 , wherein said disposable sample handling apparatus is configured as one of a sampling device in a pipette form, as a stirring device, in a dip or insertion form, or as a surface measurement device for solids.
10. The device of claim 1 , wherein said sample handling system comprises a sample transport mechanism for moving fluid into said sample chamber or cell.
11. The device of claim 1 , wherein said sample transport mechanism comprises a bellows for drawing fluid into said sample chamber or cell.
12. The device of claim 1 , wherein said sample transport mechanism comprises a piston for drawing fluid into said sample chamber or cell.
13. The device of claim 1 , wherein said sample transport mechanism comprises a pump for drawing fluid into said sample chamber or cell.
14. The device of claim 1 , wherein said sample handling system comprises a tube through which the sample is drawn into said chamber or cell, said tube having a reagent for facilitating measurement of an analyte.
15. The device of claim 14 , wherein said tube contains protrusions to facilitate mixing of said reagent with said sample.
16. The device of claim 15 , wherein said protrusions generate turbulence in said sample when said sample is drawn through said tube.
17. The device of claim 1 , wherein said a portion of said sample handling apparatus forming at least a part of said sample chamber or cell has mirrored surfaces for reflecting energy travel from said energy source to said spectral sensing detector.
18. The device of claim 17 , wherein said energy travels in said sample chamber or cell from said energy source to a first mirrored surface, from said first mirrored surface to said second mirrored surface, and from said second mirrored surface to said spectral sensing detector.
19. The device of claim 1 , wherein said sample chamber or cell has a volume of between a few hundred microliters and a few milliliters.
20. The device of claim 1 , wherein said sample handling apparatus comprises a tube with an open end for permitting optical measurements of solids at said open end.
21. The device of claim 1 , wherein said sample chamber or cell is matched to said active area of the spectral sensing detector without the aid of additional interfacing optics.
22. The device of claim 1 , wherein said sample chamber or cell is configured so that bubbles in said sample move to a position removed from an optical path between said energy source and said spectral sensing detector.
23. The device of claim 1 , wherein said on-board computer processing includes memory storage for data, calibration coefficients, methods and results.
24. The device of claim 8 , wherein said sample interface component has a surface on which is disposed a reagent for interaction with said sample.