Field imager

Abstract

A detection apparatus for detecting the presence of a sample, the detection apparatus comprising a chamber, ports for introducing a sample within the chamber, an actuation unit for establishing a controllable electromagnetic field in the chamber; and a sensing unit for sensing changes in the electromagnetic field due to the presence of the sample within the chamber. The sensing unit comprises a sensor device comprising a source and a drain embedded in a FET a gate for the FET, in which the gate is formed of a material whose conductivity is related to the electromagnetic field established in a nonconductive medium in contact with the gate.

1 - 10 . (canceled) 
   
   
       11 . A detection apparatus for detecting the presence of a sample, the detection apparatus comprising:
 a chamber;   a port for introducing a sample within the chamber;   an actuation unit for establishing a controllable electromagnetic field in the chamber; and   a FET sensing unit for sensing changes in the electromagnetic field due to the presence of the sample within the chamber.   
   
   
       12 . The detection apparatus of  claim 11 , wherein the electromagnetic field is spatially non-uniform. 
   
   
       13 . (canceled) 
   
   
       14 . (canceled) 
   
   
       15 . The detection apparatus of  claim 11  wherein the sensing unit further comprises a first sensor device made of a first FET connected to a second sensor device made of a second FET, the first FET being a p-type FET and the second FET being a n-type FET. 
   
   
       16 . The detection apparatus of  claim 11  wherein the sensing unit comprises an array of sensor devices. 
   
   
       17 . The detection apparatus of  claim 11 , wherein the actuation unit comprises an array of electrodes and the sensing unit comprises an array of sensors interspersed with the array of electrodes. 
   
   
       18 . The detection apparatus of  claim 17 , wherein at least one of the electrodes and sensors receive power from a electromagnetic source, wherein the electromagnetic energy is directed by mirrors controlled by the actuation unit. 
   
   
       19 . The detection apparatus of  claim 17  wherein at least one of the electrodes and sensors receives power from a power source controlled by the actuation unit. 
   
   
       20 . The detection apparatus of  claim 19  wherein the electrodes are elongate members, the elongate members receiving power at one end and generating the electromagnetic field at the other end in response to the power. 
   
   
       21 . The detection apparatus of  claim 17 , wherein the electrodes comprise a metal mesh. 
   
   
       22 . The detection apparatus of  claim 17 , wherein the electrodes have metallic tips. 
   
   
       23 . The detection apparatus of  claim 11  wherein the actuation unit comprises an array of electrodes. 
   
   
       24 . The detection apparatus of  claim 23  wherein the array of electrodes is arranged in a quadrupole arrangement. 
   
   
       25 . The detection apparatus of  claim 11  wherein the changes in the electromagnetic field sensed by the sensor device are used to determine the impedance of the sample. 
   
   
       26 . The detection apparatus of  claim 11  further comprising a characterization unit that uses the changes sensed by the sensor unit to make a 2D image of the electromagnetic field. 
   
   
       27 . A method of detecting a sample using dielectrophoresis, the method comprising the steps of:
 introducing the sample within a chamber;   using an actuation unit to establish a controllable electromagnetic field in the chamber; and   using a FET sensing unit to simultaneously sense changes in the electromagnetic field due to the presence of the sample within the chamber.   
   
   
       28 . The method of  claim 27  wherein the actuation unit is responsive to feedback from the sensor device. 
   
   
       29 . The method of  claim 27  wherein the actuation unit establishes a spatially non-uniform electromagnetic field. 
   
   
       30 . The method of  claim 27 , wherein using a FET sensing unit comprises providing a sensor device comprising:
 two spatially separated drains embedded in a FET;   two spatially separated gates for the FET, in which the gate is formed of a material whose conductivity is sensitive to the electromagnetic field established in a nonconductive medium in contact with the gate; and   a common source embedded in the FET;   
   
   
       31 . The method of  claim 30  wherein the FET sensing unit comprises a p-type FET and an n-type FET. 
   
   
       32 . The method of  claim 27  wherein using a FET sensing unit comprises using an array of sensor devices. 
   
   
       33 . The method of  claim 27  wherein using an actuation unit comprises using an array of electrodes. 
   
   
       34 . The method of  claim 27 , wherein using an actuation unit comprises using an array of electrodes and using a sensing unit comprises interspersing an array of sensors with the array of electrodes. 
   
   
       35 . The method of  claim 33  wherein using an array of electrodes comprises arranging the electrodes in a quadrupole arrangement. 
   
   
       36 . The method of  claim 34 , wherein using an actuation unit and using a sensing unit further comprises powering at least one of the electrodes and sensors using electromagnetic energy wherein the electromagnetic energy is directed by mirrors controlled by the actuation unit. 
   
   
       37 . The method of  claim 27  wherein the sample is organic matter. 
   
   
       38 . The method of  claim 27  wherein the sample is a cell. 
   
   
       39 . The method of  claim 27  further comprising the step of using the changes in the electromagnetic field sensed by the sensing unit to make a 2D image of the electromagnetic field. 
   
   
       40 . The method of  claim 27  further comprising the step of using a characterizing unit to determine the impedance of the sample using the changes sensed by the sensing unit.