Multiuse optical sensor

Abstract

One or more electromagnetic radiation sources, such as a light emitting diode, may emit electromagnetic waves into a volume of space. When an object enters the volume of space, the electromagnetic waves may reflect off the object and strike one or more position sensitive detectors after passing through an imaging optical system such as glass, plastic lens, or a pinhole located at known distances from the sources. Mixed signal electronics may process detected signals at the position sensitive detectors to calculate position information as well as total reflected light intensity, which may be used in medical and other applications. A transparent barrier may separate the sources and detectors from the objects entering the volume of space and reflecting emitted waves. Methods and devices are provided.

1 - 40 . (canceled) 
     
     
         41 . A method for determining a blood pressure, comprising:
 determining a pressure exerted on a surface by a body part that is pressed against the surface;   determining a photoplethysmograph of the body part; and   determining the blood pressure as a function of the pressure exerted on the surface and the photoplethysmograph.   
     
     
         42 . The method of  claim 41 , further comprising:
 emitting an electromagnetic radiation towards the surface for use in at least one of the pressure determination and the photoplethysmograph determination.   
     
     
         43 . The method of  claim 41 , further comprising:
 providing feedback regarding a placement of the body part on the surface in order to improve an accuracy of at least one of the pressure determination and the photoplethysmograph determination.   
     
     
         44 . The method of  claim 42 , further comprising:
 correcting the photoplethysmograph determination by:
 tracking a motion of the body part, and 
 compensating for the motion of the body part in order to one of correct and reject measurement data attributable to the tracked motion of the body part. 
   
     
     
         45 . The method of  claim 41 , wherein the pressure exerted on the surface and the photoplethysmograph are simultaneously determined to determine the blood pressure. 
     
     
         46 . The method of  claim 42 , wherein the emitted electromagnetic radiation is used in both of the pressure determination and the photoplethysmograph determination. 
     
     
         47 . The method of  claim 44 , wherein the tracking of the motion of the body part is performed by a position sensitive detector that measures a position of the electromagnetic radiation reflected off of the body part by generating first and second currents at first and second ends, respectively, of the position sensitive detector, the first and second currents varying depending on a light distribution of the reflected electromagnetic radiation on the position sensitive detector facing the surface 
     
     
         48 . A device for determining a blood pressure, comprising:
 means for determining a pressure exerted on a surface by a body part that is pressed against the surface;   means for determining a photoplethysmograph of the body part; and   means for determining the blood pressure as a function of the pressure exerted on the surface and the photoplethysmograph.   
     
     
         49 . The device of  claim 48 , further comprising:
 means for emitting an electromagnetic radiation towards the surface for use in at least one of the pressure determination and the photoplethysmograph determination.   
     
     
         50 . The device of  claim 48 , further comprising:
 means for providing feedback regarding a placement of the body part on the surface in order to improve an accuracy of at least one of the pressure determination and the photoplethysmograph determination.   
     
     
         51 . The device of  claim 49 , further comprising:
 means for correcting the photoplethysmograph determination, wherein the means for correcting includes:
 means for tracking a motion of the body part, and 
 means for compensating for the motion of the body part in order to one of correct and reject measurement data attributable to the tracked motion of the body part. 
   
     
     
         52 . The device of  claim 48 , wherein the pressure exerted on the surface and the photoplethysmograph are simultaneously determined to determine the blood pressure. 
     
     
         53 . The device of  claim 49 , wherein the means for emitting the electromagnetic radiation towards the surface is used in both of the pressure determination and the photoplethysmograph determination. 
     
     
         54 . The device of  claim 51 , wherein the means for tracking the motion of the body part measures a position of the electromagnetic radiation reflected off of the body part by generating first and second currents at first and second ends, respectively, of the means for tracking the motion of the body part, the first and second currents varying depending on a light distribution of the reflected electromagnetic radiation on the means for tracking the motion of the body part that faces the surface 
     
     
         55 . A device for determining a blood pressure, comprising:
 at least one light source emitting electromagnetic radiation;   a surface arranged in a vicinity of the at least one light source;   a detector sensing the electromagnetic radiation reflected from a body part on the surface; and   electronics:
 determining a pressure exerted on the surface by the body part; 
 determining a photoplethysmograph of the body part; and 
 determining the blood pressure as a function of the pressure exerted on the surface and the photoplethysmograph. 
   
     
     
         56 . The device of  claim 55 , wherein the at least one light source is configured to emit the electromagnetic radiation towards the surface for use in at least one of the pressure determination and the photoplethysmograph determination. 
     
     
         57 . The device of  claim 55 , wherein the electromagnetic radiation reflected off of the surface is used in the photoplethysmograph determination. 
     
     
         58 . The device of  claim 56 , wherein the at least one light source is configured to emit the electromagnetic radiation towards the surface for use in both the pressure determination and the photoplethysmograph determination. 
     
     
         59 . The device of  claim 55 , wherein the electronics calculate feedback regarding a placement of the body part on the surface in order to improve an accuracy of at least one of the pressure determination and the photoplethysmogrpah determination. 
     
     
         60 . The device of  claim 55 , wherein:
 while the body part is on the surface and for each of at least two points in time:
 the pressure is determined and the photoplethysmograph is determined, 
 a time from the at least two points in time is recorded, and 
 the determined pressure, the determined photoplethysmograph, and the recorded time are linked as a record in a record set stored in memory; and 
   the blood pressure is determined based on a correlation established using the record set stored in memory.