Obtaining information about analytes using optical cavity output light

• US 7,554,673 B2
• Filed: 02/05/2007
• Issued: 06/30/2009
• Est. Priority Date: 02/05/2007
• Status: Active Grant

• Current Assignee: Xerox Corporation (Xerox Holdings Corp.)
• Original Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Inventors: Kiesel, Peter, Bassler, Michael, Schmidt, Oliver
• Primary Examiner(s): Chowdhury; Tarifur
• Assistant Examiner(s): LAPAGE, MICHAEL P
• Application Number:
  US11/702,470
• Publication Number:
  US 20080186504A1
• Time in Patent Office: 876 Days
• Field of Search: 356/518, 356/244, 356/454, 356/480
• US Class Current: 356/519
• CPC Class Codes: B01L 2200/10 Integrating sample preparation and analysis in single entity, e.g. lab-on-a-chip concept
• CPC Class Codes: B01L 2300/168 Specific optical properties, e.g. reflective coatings
• CPC Class Codes: B01L 3/5085 for multiple samples, e.g. microtitration plates
• CPC Class Codes: G01J 3/26 using multiple reflection, e.g. Fabry-Perot interferometer, variable interference filters
• CPC Class Codes: G01N 2021/391 Intracavity sample
• CPC Class Codes: G01N 21/031 Multipass arrangements

Abstract

While two or more analytes within an optical cavity move relative to an array of photosensing elements, the cavity provides output light that has a position/time varying intensity function that depends on optical characteristics of the analytes and on the relative movement. The output light is photosensed to obtain sensing results that depend on the position/time varying intensity function. The sensing results are used to obtain information about at least one of the analytes. The relative movement can, for example, be caused by moving analytes within channels within the cavity, such as by causing flow of a medium that carries the analytes through the channels. Or the analytes can be in wells of a biochip, with the cavity defined by reflective slides on opposite surfaces of the biochip, and the slides and biochip can be caused to move together relative to the array.

Claims

1. A method of using optical cavities;

the method comprising;

operating an optical cavity to provide output light and operating an array of photosensing elements to provide sensing results in response to the output light;

a set of two or more analytes moving within the optical cavity relative to the array;

the output light having a position/time varying intensity function that depends on optical characteristics of the analytes and on the relative movement;

the sensing results depending on the position/time varying intensity function; and

using the sensing results to obtain information about at least one of the analytes.

2. The method of claim 1, further comprising:

causing the relative movement between the analytes and the array.

3. The method of claim 1 in which the act of operating the optical cavity and operating the array comprises:

operating the optical cavity to provide output light in a set of one or more modes;

each mode in the set having a respective intensity functions;

the respective intensity function of at least one mode in the set having a position/time variation that depends on optical characteristics of the analytes.

4. The method of claim 1 in which the act of using the sensing results comprises:

obtaining information about the relative movement; and

using the information about the relative movement to obtain the information about at least one of the analytes from the sensing results.

5. A system comprising:

an optical cavity component that includes an optical cavity in which two or more analytes are present;

the optical cavity being operable to provide output light;

an array of photosensing elements;

an analyte/array relative movement component that causes relative movement between the analytes in the optical cavity and the array of photosensing elements;

the output light of the optical cavity having a position/time varying intensity function that depends on optical characteristics of the analytes and on the relative movement;

a photosensing component that photosenses the output light to obtain sensing results that depend on the varying intensity function; and

an information obtaining component that uses the sensing results to obtain information about at least one of the analytes.

6. The system of claim 5 in which the optical cavity is one of a laser cavity and a homogeneous or inhomogeneous transmissive cavity.

7. The system of claim 5 in which the information obtaining component includes processing circuitry that, in operation, obtains information about the relative movement and uses the information about the relative movement to obtain the information about at least one of the analytes from the sensing results.

8. The system of claim 5 in which the photosensing component photosenses the output light by operating the array of photosensing elements.

9. A method of obtaining information about analytes using optical cavities operable to provide output light in one or more modes, output light in each mode having an intensity function within a respective photon energy subrange;

the method comprising;

operating an optical cavity to provide output light and operating an array of photosensing elements to provide sensing results in response to the output light;

a set of two or more analytes moving within the optical cavity relative to the array;

each analyte following a respective path relative to the array during the relative movement and having an optical characteristic that affects the output light of the cavity along its path;

in response, the output light having a position/time varying intensity function that depends both on the optical characteristics of the analytes and on the relative movement;

the act of operating the optical cavity and operating the array comprising;

at each of two or more positions along the paths, photosensing in the respective photon energy subranges of respective ones of the modes to obtain sensing results that depend on the position/time varying intensity function; and

using the sensing results to obtain information about at least one of the analytes.

10. The method of claim 9, further comprising:

causing relative movement between the analytes and the array.

11. The method of claim 10 in which the analytes are in a medium in a set of one or more channels within the cavity and the array is connected to the cavity, the act of causing relative motion comprising:

causing flow of the medium through the channels.

12. The method of claim 11 in which the cavity is a transmissive cavity and the modes are transmission modes or reflection modes;

the act of operating the optical cavity and operating the array comprising;

photosensing in the respective photon energy subranges of first and second ones of the modes along first and second ones of the channels, respectively.

13. The method of claim 10 in which the analytes are in wells of a biochip and the cavity is defined by reflective slides on opposite surfaces of the biochip, the act of causing relative motion comprising:

causing the slides and the biochip to move together relative to the array.

14. The method of claim 9 in which the act of operating the optical cavity and operating the array comprises:

obtaining photosensed quantities that indicate intensities sensed by respective elements of the array.

15. The method of claim 9 in which the act of using the sensing results comprises:

obtaining information about at least one of refractive index and absorption of at least one of the analytes.

16. The method of claim 9 in which the position/time varying intensity function includes one or more peaks, the act of using the sensing results comprises:

using the sensing results to detect a change in a feature of the varying intensity function.

17. The method of claim 16 in which the feature is one of a central value, a maximum intensity, a contrast, and an intermediate intensity width of at least one of the peaks.

18. The method of claim 9 in which the act of using the sensing results comprises:

obtaining information about the relative movement; and

using the information about the relative movement to obtain the information about at least one of the analytes from the sensing results.

19. A system comprising:

an optical cavity component that includes a light-transmissive region at least partially bounded by light-reflective components, the light-transmissive region and the light-reflective components having characteristics such that, during optical cavity operation, a measurable portion of light within the light-transmissive region is reflected more than once across the light-transmissive region with constructive interference and destructive interference occurring in the light-transmissive region and with the optical cavity component providing output light from the light-transmissive region in one or more modes;

the output light provided in each mode having respective intensity within a respective photon energy subrange;

the light-transmissive region being operable as at least one of;

a laser cavity;

an emitting optical cavity;

a transmissive cavity; and

a Fabry-Perot cavity;

a photosensing component that includes an array of photosensing elements;

an analyte/array relative movement component that causes relative movement between one or more analytes in the light-transmissive region and the array of photosensing elements;

a first mode'"'"'s intensity changing as a function both of position and of time, change in the first mode'"'"'s intensity depending both on optical characteristics of the one or more analytes in the light-transmissive region and on the relative movement;

the array of photosensing elements photosensing the output light in the first mode'"'"'s photon energy subrange and, in response, the photosensing component providing sensing results that depend on the first mode'"'"'s intensity; and

an information obtaining component that obtains information about the relative movement and uses the information about the relative movement to obtain information from the sensing results, the information obtained from the sensing results including information about at least one of the one or more analytes.

20. The system of claim 19 in which the first mode'"'"'s intensity has a respective intensity peak.

21. The system of claim 20 in which the light-transmissive region is operable as a transmissive cavity;

the first mode being a transmission mode or a reflection mode.

22. The system of claim 21 in which the respective intensity peak of the first mode'"'"'s intensity includes information about an optical characteristic of one or more of the analytes.

23. The system of claim 19 in which the array of photosensing elements is on a photosensing IC.

24. The system of claim 19 in which the information obtaining component includes processing circuitry connected to receive the sensing results from the photosensing component.

25. The system of claim 19 in which the optical cavity component includes first and second light-reflective components and in which the output light has a laterally varying photon energy distribution;

in operation, the light-transmissive region having at least one of;

laterally varying optical thickness between the first and second light-reflective components, the light-transmissive region being operable as an inhomogeneous transmissive cavity; and

angled illumination received through one of the first and second light-reflective components from a point light source.

26. A method of using the system of claim 19, the method comprising:

operating the optical cavity component and the relative movement component so that relative movement occurs between an analyte in the light-transmissive region and the array, the optical cavity component provides output light from the light-transmissive region in the first mode, the analyte causes local variation in the output light provided in the first mode, and the output light with the local variation is incident at changing positions on the array;

operating the photosensing component to photosense the output light with the local variation and, in response, to provide sensing results that depend on the change in the first mode'"'"'s intensity as a function both of position and of time; and

operating the information obtaining component to obtain the information about the relative movement and use the information about the relative movement to obtain the information about the analyte from the sensing results.

27. The method of claim 26 in which the one or more analytes are in a medium in a set of one or more channels within the light-transmissive region and the array is connected to the optical cavity component, the act of operating the optical cavity component and the relative movement component comprising:

operating the relative movement component to cause flow of the medium through the channels.

28. The method of claim 27 in which the set of channels includes at least two channels.

29. The method of claim 28 in which all the channels in the set are substantially parallel.

30. The method of claim 28 in which the act of operating the optical cavity component and the relative movement component comprises:

operating the optical cavity component to provide output light in a second mode;

the act of operating the photosensing component comprising;

operating the array so that first and second sets of the photosensing elements photosense in the first and second modes'"'"' photon energy ranges, respectively, along first and second channels, respectively.

31. The method of claim 26 in which the analytes are in wells of a biochip and the optical cavity component includes reflective slides on opposite surfaces of the biochip, the act of operating the optical cavity component and the relative movement component comprising:

causing the slides and the biochip to move together relative to the array.

32. The method of claim 26 in which the act of operating the information obtaining component comprises:

obtaining information about at least one of refractive index and absorption of at least one of the analytes.

33. A method of using an optical cavity component that includes first and second channels within a light-transmissive region;

the light-transmissive region being at least partially bounded by light-reflective components;

the optical cavity component being operable to provide output light in a set of modes that includes first and second modes;

the method comprising;

operating the optical cavity component to provide respective output light from each of the first and second channels and operating an array of photosensing elements to provide respective sensing results in response to each channel'"'"'s output light;

first and second sets of analytes moving relative to the array within the first and second channels, respectively, while the optical cavity component provides the respective output light;

in each channel, each analyte having an optical characteristic that affects the channel'"'"'s output light;

each channel'"'"'s output light having respective intensity that changes as a function both of position and of time, change in the channel'"'"'s output light intensity depending on both optical characteristics and relative movement of the respective set of analytes; and

using the sensing results to obtain information about at least one of the analytes;

the act of operating the optical cavity component and operating the array comprising;

along each of the first and second channels, operating a respective set of photosensing elements in the array to photosense output light in a respective photon energy subrange, the respective photon energy subranges of the first and second channels including the first and second modes, respectively;

each channel'"'"'s set of photosensing elements providing sensing results that depend on the channel'"'"'s output light intensity.

34. The method of claim 33 in which the act of operating the optical cavity component and operating the array further comprises:

for each of the first and second channels, transmitting the channel'"'"'s output light through a transmission structure with a laterally varying energy output function so that the channel'"'"'s set of photosensing elements receives a portion of the output light in the channel'"'"'s photon energy subrange;

the respective photon energy subranges of the first and second channels being different photon energy subranges.