Sensor Apparatus

Abstract

The present invention relates to a sensor apparatus having a structure capable of obtaining digital values of signal components with a high accuracy using an A/D conversing circuit with the outputted digital value thereof having a small number of expressive bits. In the sensor apparatus, a voltage value corresponding to the amount of incident light to a photodiode is held by a holding circuit through an integrating circuit and a CDS circuit. Meanwhile, a voltage value corresponding to the amount of incident light to an adjacent photodiode is held by another holding circuit through an integrating circuit and a CDS circuit. The voltage values held by the respective different holding circuits are inputted to a subtracting circuit through different paths. The subtracting circuit outputs a voltage value corresponding to the difference between the two inputted voltage values. In an A/D converting section, the difference voltage outputted from the subtracting circuit is converted into a digital value.

1 . A sensor apparatus comprising: 
 a sensor array section including N sensor elements (N represents an integer of 2 or more) and outputting a voltage value V n  in response to the result of sensing by the n-th sensor element (“n” represents any integer of 1 or more but N or less) among said N sensor elements;    a difference operating section outputting a voltage value U n  (n≠1) corresponding to the difference (V n −V n-1 ) between the voltage values V n  and V n-1  among N voltage values V 1  to V N  outputted from said sensor array section; and    an A/D converting section converting the voltage value U n  outputted from said difference operating section into a digital value.    
     
     
         2 . A sensor apparatus according to  claim 1 , wherein said A/D converting section converts at least one voltage value of the N voltage values V 1  to V N  into a digital value.  
     
     
         3 . A sensor apparatus according to  claim 1 , further comprising a holding section once holding the N voltage values V 1  to V N  outputted from said sensor array section, and 
 wherein said difference operating section outputs the voltage value U n  based on the N voltage values V 1  to V N  held by said holding section.    
     
     
         4 . A sensor apparatus according to  claim 1 , wherein each of said N sensor elements includes a photodiode.  
     
     
         5 . A sensor apparatus comprising: 
 a sensor array section including N sensor elements (N represents an integer of 2 or more) and adapted to output a voltage value V n  in response to the result of sensing by the n-th sensor element (“n” represents any integer of 1 or more but N or less) among said N sensor elements;    a difference operating section outputting a voltage value W n  corresponding to the difference (V n −V n0 ) between a specific voltage value V n0  and the voltage value V n  among N voltage values V 1  to V N  outputted from said sensor array section; and    an A/D converting section converting the voltage value W n  outputted from said difference operating section into a digital value.    
     
     
         6 . A sensor apparatus according to  claim 5 , wherein said A/D converting section converts the specific voltage value V n0  into a digital value.  
     
     
         7 . A sensor apparatus according to  claim 5 , further comprising a holding section once holding the N voltage values V 1  to V N  outputted from said sensor array section, and 
 wherein said difference operating section outputs the voltage value W n  based on the N voltage values V 1  to V N  held by said holding section.    
     
     
         8 . A sensor apparatus according to  claim 5 , wherein each of said N sensor elements includes a photodiode.