Time-delay integration imaging method and apparatus using a high-speed in-pixel analog photon counter

• US 8,653,435 B2
• Filed: 05/27/2013
• Issued: 02/18/2014
• Est. Priority Date: 09/06/2010
• Status: Expired due to Fees

• Current Assignee: King Abdullah University of Science and Technology
• Original Assignee: King Abdullah University of Science and Technology
• Inventors: Eldesouki, Munir
• Primary Examiner(s): NGUYEN, SANG H
• Application Number:
  US13/902,857
• Publication Number:
  US 20130248689A1
• Time in Patent Office: 267 Days
• Field of Search: 250/208.1, 250/214.DC, 250/241.A, 250/214.1, 250/214.C, 356213-235
• US Class Current: 250/214.A
• CPC Class Codes: G01J 1/46 using a capacitor
• CPC Class Codes: H04N 25/711 Time delay and integration [TDI] registers; TDI shift registers
• CPC Class Codes: H04N 25/768 for time delay and integration [TDI]
• CPC Class Codes: H04N 25/772 comprising A/D, V/T, V/F, I/T or I/F converters

Abstract

A high speed analog photon counter and method is provided. In one aspect, the method includes accumulating an electric charge in a capacitor of a circuit electrically coupled to a current source. The method further includes comparing the electric charge accumulated in the capacitor of the circuit with a reference voltage through a comparator of the circuit electrically coupled to an output of the capacitor. The method also includes increasing a speed of operation of a measurement device through implementing the circuit inside a pixel. The method further includes transferring the accumulated electric charge to a circuit of an adjacent pixel and synchronizing the transfer of the accumulated electric with a movement of an object captured by an image sensor device before implementing a time-delay integration operation.

Claims

1. A method of time-delay integration comprising:

accumulating an electric charge in a capacitor of a circuit electrically coupled to a current source of the circuit;

comparing the electric charge accumulated in the capacitor of the circuit with a reference voltage through a comparator of the circuit electrically coupled to an output of the capacitor;

increasing a speed of operation of a measurement device through implementing the circuit inside a pixel;

transferring the accumulated electric charge to a circuit of an adjacent pixel; and

synchronizing the transfer of the accumulated electric charge with a movement of an object captured by an image sensor device before implementing a time-delay integration operation;

delivering the electric charge to the circuit through the current source;

resetting the capacitor of the circuit when the electric charge accumulated in the capacitor of the circuit matches the reference voltage;

measuring an intensity of light through the circuit and the comparator of the circuit;

generating a digital pulse at an output of a photodiode corresponding to a photon incident on the photodiode,

wherein the output of the photodiode is coupled to an input of the current source;

delivering an amount of the electric charge proportional to a pulse width of the digital pulse; and

increasing an output voltage of the capacitor of the circuit proportional to each of the electric charge accumulated in the capacitor, wherein the increase in the output voltage of the capacitor to correspond to the photon incident on the photodiode.