Multiple wavelength sensor emitters

1. A physiological sensor configured to measure an indication of a physiological characteristic of a living patient, the physiological sensor comprising:

a plurality of light emitting sources arranged to impinge light on body tissue of a living patient, each light emitting source activated by addressing at least one of a plurality of rows and at least one of a plurality of columns of an electrical grid, the light emitting sources capable of transmitting light of a plurality of wavelengths, wherein there are fewer light emitting sources than intersections of the rows and columns;

a detector responsive to the transmitted light after attenuation by body tissue of the living patient, the body tissue including pulsating blood, wherein the detector is configured to generate a signal indicative of a physiological characteristic of the living patient; and

a sensor housing configured to position the plurality of light emitting sources and the detector with respect to the body tissue of the living patient.

2. The physiological sensor according to claim 1 wherein multiple ones of the light emitting sources are capable of transmitting light of the same wavelength, the multiple ones simultaneously activated by addressing one of the rows.

3. The physiological sensor according to claim 2 wherein:

the light emitting sources are LEDs, and

each of the LEDs have an anode in common with one of the rows and a cathode in common with one of the columns so that driving one of the rows and one of the columns activates a unique one of the LEDs.

4. The physiological sensor according to claim 3 further comprising:

a plurality of row drivers in communication with the rows; and

a plurality of column drivers in communication with the columns,

wherein a selected row driver sources current to a corresponding row and selected column driver sinks current from a corresponding column so as to activate an addressed one of the LEDs.

5. The physiological sensor according to claim 4 wherein deselected ones of the row drivers pull corresponding rows to a low voltage via a functional switch configured to operably connect deselected rows to a low voltage source and deselected ones of the column drivers pull corresponding columns to a high voltage via a functional switch configured to operably connect deselected columns to a high voltage source so as to substantially block parasitic current from unaddressed ones of the LEDs.

6. The physiological sensor according to claim 5 wherein the electrical grid comprises at least three rows or at least three columns.

7. The physiological sensor according to claim 5 wherein the electrical grid communicates with at least eight LEDs.

8. The physiological sensor of claim 1 , wherein the plurality of light emitting sources and the detector are coupled to a flex circuit.

9. The physiological sensor of claim 1 , wherein the plurality of light emitting sources are arranged to minimize optical pathlength differences.

10. The physiological sensor of claim 1 , wherein the plurality of light emitting sources are arranged to facilitate equalization.

11. The physiological sensor of claim 1 , wherein the electrical grid is arranged so as to prevent parasitic currents from unwanted activation of the light emitting sources.

12. The physiological sensor of claim 1 , wherein the light emitting sources correspond to multiple different wavelengths of light, the light sources being arranged in clusters corresponding to said wavelengths.

13. The physiological sensor of claim 12 , wherein the light sources are arranged in clusters corresponding to said wavelengths so as to minimize pathlength variations.

14. The physiological sensor of claim 12 , wherein the light sources are arranged in clusters corresponding to said wavelengths so as to facilitate equalization of intensities.

15. The physiological sensor of claim 12 , wherein the light emitting sources are further configured to comprise wavelengths usable to measure two or more of HbCO, METHb, and SpO 2 .

16. A method for measuring a physiological characteristic of a living patient, the method comprising:

positioning a sensor with respect to body tissue of a living patient, the sensor comprising a plurality of light emitting sources arranged to impinge light on the body tissue and a detector, the light emitting sources being arranged in an electrical grid comprising rows and columns, wherein there are fewer light emitting sources than intersections of the rows and columns;

activating the plurality of light emitting sources, said activating each light emitting source comprising addressing at least one of the rows and at least one of the columns of the electrical grid, such that a plurality of wavelengths of light are emitted from the plurality of light emitting sources;

detecting the light with the detector after attenuation by the body tissue of the living patient, the body tissue comprising pulsating blood; and

generating a signal reflecting a physiological characteristic of the living patient responsive to the detected light.

17. The method of claim 16 , wherein the electrical grid is arranged so as to prevent parasitic currents from unwanted activation of the light emitting sources.

18. The method of claim 16 , further comprising connecting deselected columns to a voltage source to substantially block parasitic current from unaddressed ones of the light emitting sources.

19. The method of claim 16 , wherein the light emitting sources correspond to multiple different wavelengths of light, the light sources being arranged in clusters corresponding to said wavelengths.

20. The method of claim 19 , wherein the light sources are arranged in said clusters corresponding to said wavelengths so as to minimize pathlength variations.

21. The method of claim 19 , wherein the light sources are arranged in said clusters corresponding to said wavelengths so as to facilitate equalization of intensities.

22. The method of claim 16 , wherein the light emitting sources are further configured to emit wavelengths adapted to measure two or more of HbCO, METHb, and SpO 2 .