Systems and methods for a digital image sensor

Abstract

A system, method, and computer program product are provided for generating an image stack. In use, one or more exposure parameters for an image stack are configured. Next, a capture command is received. Further, a pixel array is initialized within an image sensor of the camera module. Moreover, one or more ambient images are sampled within one or more corresponding analog storage planes. Next, if it is determined whether a strobe unit is enabled, where, if it is determined that the strobe unit is enabled, one or more strobe images are sampled within the corresponding analog storage planes.

We claim: 
     
         1 . A camera module, comprising:
 circuitry configured to:   set one or more exposure parameters for an image stack;   receive a capture command;   initialize a pixel array within an image sensor of the camera module; and   sample two or more images within at least one corresponding analog storage plane, wherein the two or more image include at least one ambient image and at least one strobe image, the at least one strobe image being sampled using a strobe unit.   
     
     
         2 . The camera module of  claim 1 , wherein the image stack comprises the at least one ambient image and the at least one strobe image. 
     
     
         3 . The camera module of  claim 1 , wherein to set the one or more exposure parameters, the circuitry is configured to at least write one or more registers within the image sensor that specifies exposure time for each of at least one corresponding analog storage plane, or write one or more registers within the image sensor that specifies exposure sensitivity for each of the at least one corresponding analog storage plane, or write one or more registers within the image sensor that specifies exposure time and exposure sensitivity for at least one of the at least one corresponding analog storage plane. 
     
     
         4 . The camera module of  claim 1 , wherein the camera module is implemented within at least one of a digital camera, or a mobile device. 
     
     
         5 . The camera module of  claim 1 , wherein to initialize the pixel array, the circuitry is configured to drive voltages on internal nodes of photo-sensitive cells within the at least one corresponding analog storage plane to a reference voltage. 
     
     
         6 . The camera module of  claim 1 , wherein the camera module is configured to store both the one or more ambient images ambient images and the one or more strobe images concurrently within the at least one corresponding analog storage plane. 
     
     
         7 . The camera module of  claim 1 , wherein the camera module is configured to offload the at least one ambient image prior to sampling the at least one strobe image within the at least one corresponding analog storage plane. 
     
     
         8 . The camera module of  claim 1 , wherein the circuitry is further configured to enable simultaneous integration of a photographic scene for at least two corresponding analog storage planes. 
     
     
         9 . The camera module of  claim 8 , wherein two or more analog sampling circuits within the at least two corresponding analog storage planes each integrate a respective image during a sampling interval. 
     
     
         10 . The camera module of  claim 1 , wherein the circuitry is further configured to:
 enable integration to proceed during a first sampling interval for at least two different analog storage planes;   disable integration for at least one analog storage plane of the at least two different analog storage planes; and   enable integration to proceed during a second sampling interval for at least one analog storage plane of the at least two different analog storage planes.   
     
     
         11 . The camera module of  claim 10 , wherein the camera module is configured to transmit image data corresponding to each of the at least two different analog storage planes to a processing unit. 
     
     
         12 . The camera module of  claim 11 , wherein the processing unit is configured to generate exposure parameters. 
     
     
         13 . The camera module of  claim 1 , wherein to sample two or more images, the circuitry is configured to:
 assert an active low state to initialize cells of the pixel array,   enable integration of a first signal from an associated photodiode on a first analog sampling circuit to generate an ambient sample comprising the at least one ambient image; and   determine whether the strobe unit is enabled; and   if it is determined that the strobe unit is enabled,   enable integration of a second signal from the associated photodiode on a second analog sampling circuit to generate a strobe sample comprising the at least one strobe image;   wherein a strobe enable signal is asserted after the sampling of the at least one ambient image is completed.   
     
     
         14 . The camera module of  claim 13 , wherein the circuitry is further configured to reset the photodiode after disabling integration of the signal on the first analog sampling circuit. 
     
     
         15 . The camera module of  claim 1 , wherein to sample two or more images, the circuitry is configured to:
 assert an active low state to initialize cells of the pixel array,   enable integration of a first signal from an associated photodiode on a first analog sampling circuit;   disable integration of the first signal on the first analog sampling circuit;   enable integration of a second signal from the associated photodiode on a second analog sampling circuit;   disable integration of the second signal on the second analog sampling circuit; and   enable integration of the first signal on the first analog sampling circuit,   wherein a strobe enable signal is asserted between two different sampling intervals for a same ambient image.   
     
     
         16 . The camera module of  claim 1 , wherein to sample two or more images, the circuitry is configured to:
 assert an active low state to initialize cells the pixel array,   enable, during at least two separate time intervals, integration of at least one signal from an associated photodiode on at least two separate analog sampling circuits,   disable, after the at least two separate time intervals, integration of the at least one signal on the at least two separate analog sampling circuits,   determine whether the strobe unit is enabled after the at least two separate time intervals; and   if it is determined that the strobe unit is enabled,   enable integration of a third signal on a third analog sampling circuit,   wherein the integrated at least first signal of the at least two separate analog sampling circuits comprises at least one respective ambient sample of at least one ambient image of the one or more ambient images, and the integrated third signal of the third analog sampling circuit comprises a first strobe sample of a first strobe image of the one or more strobe images.   
     
     
         17 . A system, comprising:
 a camera module, configured to sample a photographic scene;   a processing unit, coupled to the camera module, and configured to:
 configure one or more exposure parameters for the image stack; 
 receive a capture command; 
 initialize a pixel array within an image sensor of the camera module; and 
 sample two or more images within at least one corresponding analog storage plane, wherein the two or more image include at least one ambient image and at least one strobe image, the at least one strobe image being sampled using a strobe unit. 
   
     
     
         18 . A method, comprising:
 configuring one or more exposure parameters for an image stack;   receiving a capture command;   initializing a pixel array within an image sensor of a camera module; and   sampling two or more images within at least one corresponding analog storage plane, wherein the two or more image include at least one ambient image and at least one strobe image, the at least one strobe image being sampled using a strobe unit.