Solid-state image pickup device having an accumulation gate for reading out, accumulating, and allocating signal charges

Abstract

Disclosed are a solid-state image-pickup device and a driving method thereof, more particularly, the present invention relates to a solid-state image-pickup device comprising a sensor array comprising a plurality of sensors; and a plurality of transfer registers for transferring signal charges from said sensors of said sensor array, wherein an accumulation gate for reading out signal charges from said sensors at the same time, accumulating said signal charges and allocating said signal charges to said transfer registers is provided between said sensor array and said transfer registers. As a result, it is possible to provide a solid-state image-pickup device capable of producing a good signal output by eliminating variations in sensitivity from sensor to sensor and a deviation in signal-charge fetching between sensors and to provide a method of driving the solid-state image-pickup device.

1 - 8 . (canceled)  
   
   
       9 . A solid-state image-pickup device having: 
 a sensor array comprising a plurality of sensors; and    a first and second transfer register for transferring signal charges generated in said sensors of said sensor array,    at least a third transfer register is formed between said first transfer register and said second transfer register for storing temporarily and transferring said signal charges from said first transfer register to said second transfer register;    wherein a read-out gate is provided between the sensor array and an accumulation region such that the read-out gate, when asserted, causes charges generated in the sensor array to be transferred to the accumulation region as a function of an applied read-out gate control signal, the accumulation region and a corresponding accumulation gate are provided between the read-out gate and said first transfer register.    
   
   
       10 . The solid-state image-pickup device according to  claim 9 , wherein said accumulation gate creates a difference in electric potential oriented in a direction of transfer of said signal charges.  
   
   
       11 . The solid-state image-pickup device according to  claim 9  wherein signal charges of said sensors are stored in said accumulation region to be allocated in units of electrical charge each originated by one of said sensors.  
   
   
       12 . The solid-state image-pickup device according to  claim 9  wherein signal charges of said sensors are allocated to respective first and second transfer registers for each odd sensor and each even sensor of said sensor array.  
   
   
       13 . A method of driving a solid-state image-pickup device having: 
 a sensor array comprising a plurality of sensors;    first and second transfer registers for transferring signal charges generated in said sensors of said sensor array;    at least a third transfer register formed between said first transfer register and said second transfer register for storing temporarily and transferring said signal charges from said first transfer register to said second transfer register;    a read-out gate is provided between the sensor array and an accumulation region such that the read-out gate, when asserted, causes charges generated in the sensor array to be transferred to the accumulation region as a function of an applied read-out gate control signal, the accumulation region and a corresponding accumulation gate are provided between said read-out gate and said first transfer register,    said method comprising the steps of:    reading out signal charges generated in said sensors in a row closest to said accumulation region at a same time via the read-out gate;    allocating said signal charges of said sensors from said accumulation region to said first transfer register; and    driving said first and second transfer registers to output said signal charges.    
   
   
       14 . The method of driving a solid-state image-pickup device according to  claim 13  whereby said first and second transfer registers are driven at the same time and in the same direction.  
   
   
       15 . The method of driving a solid-state image-pickup device according to  claim 13  whereby signal charges of said sensors are allocated to respective first and second transfer registers for each odd sensor and each even sensor of said sensor array.  
   
   
       16 . The solid-state image-pickup device according to  claim 13 , wherein said third transfer register has a same number of columns as said first and second transfer registers.  
   
   
       17 . The method of driving a solid-state image-pickup device according to  claim 13 , wherein said third transfer register has a same number of columns as said first and second transfer registers.  
   
   
       18 . The solid-state image-pickup device according to  claim 9 , wherein said accumulation gate and said read-out gate share a common gate electrode.  
   
   
       19 . The method of driving a solid-state image-pickup device according to  claim 13 , wherein said step of reading out and said step of allocating are carried out through a common gate electrode.  
   
   
       20 . A solid-state image-pickup device having: 
 a sensor array comprising a plurality of sensors; and    first and second transfer registers for transferring signal charges generated in said sensors of said sensor array,    at least a third transfer register is formed between said first transfer register and said second transfer register for storing temporarily and transferring said signal charges from said first transfer register to said second transfer register;    wherein a read-out gate is provided between the sensor array and an accumulation region such that the read-out gate, when asserted, causes charges generated in the sensor array to be transferred to the accumulation region as a function of an applied read-out gate control signal, the accumulation region and a corresponding accumulation gate are provided between the read-out gate and said first transfer register, the accumulation region being directly connected to the sensor array via the readout gate without any vertical transfer registers between the sensor array and the accumulation region.    
   
   
       21 . A method of driving a solid-state image-pickup device having: 
 a sensor array comprising a plurality of sensors;    first and second transfer registers for transferring signal charges generated in said sensors of said sensor array;    at least a third transfer register formed between said first and second transfer registers for storing temporarily and transferring said signal charges from said first transfer register to said second transfer register;    a read-out gate provided between the sensor array and an accumulation region such that the read-out gate, when asserted, causes charges generated in the sensor array to be transferred to the accumulation region as a function of an applied read-out gate control signal, the accumulation region and a corresponding accumulation gate are provided between said read-out gate and said first transfer register, the accumulation region being directly connected to the sensor array via the readout gate without any vertical transfer registers between the sensor array and the accumulation region;    said method comprising the steps of:    reading out signal charges generated in said sensors in a row closest to said accumulation region at a same time via the read-out gate;    allocating said signal charges of said sensors from said accumulation region to said first transfer register; and    driving said first and second transfer registers to output said signal charges.    
   
   
       22 . The solid-state image-pickup device according to  claim 9 , wherein only a signal driving the read-out gate, a signal driving the accumulation gate, and respective drive signals driving the first, second, and third transfer registers effect the distribution of signal charges in the vertical direction from the imaging array to each of the transfer registers.  
   
   
       23 . The method of driving a solid-state image-pickup device according to  claim 13 , wherein the steps of reading, allocating, and driving are accomplished by utilizing only a signal driving the read-out gate, a signal driving the accumulation gate, and respective drive signals driving the first, second, and third transfer registers.  
   
   
       24 . The solid-state image-pickup device according to  claim 9 , wherein either one of the odd columns and the even columns are transferred out of the accumulation region prior to the other one of the odd columns and the even columns.  
   
   
       25 . The method of driving a solid-state image-pickup device according to  claim 15 , wherein during said step of allocating, either one of the odd columns and the even columns are transferred out of the accumulation region prior to the other one of the odd columns and the even columns.  
   
   
       26 . The solid-state image-pickup device according to  claim 24 , wherein at least two-phase transfer clocks are utilized in said first and second transfer registers, and wherein the state of the two-phase transfer clocks at least partly determines which of the odd or even columns are transferred in the vertical direction.  
   
   
       27 . The method of driving a solid-state image-pickup device according to  claim 25 , wherein at least two-phase transfer clocks are utilized in said first and second transfer registers, and wherein during said step of allocating, the state of the two-phase transfer clocks at least partly determines which of the odd or even columns are transferred in the vertical direction.  
   
   
       28 . The solid-state image-pickup device according to  claim 9 , wherein at least two-phase transfer clocks are utilized in said first transfer register, and a signal driving said accumulation gate and said two-phase transfer clocks determine which signal charges are transferred from said accumulation region to said first transfer register.  
   
   
       29 . The solid-state image-pickup device according to  claim 28 , wherein at least two-phase transfer clocks are utilized in said second transfer register, and a signal driving said third transfer register and said two-phase transfer clocks determine which signal charges are transferred from said third transfer register to said second transfer register.  
   
   
       30 . The method of driving a solid-state image-pickup device according to  claim 13 , wherein at least two-phase transfer clocks are utilized in said first transfer register, and a signal driving said accumulation gate and said two-phase transfer clocks determine which signal charges are transferred from said accumulation region to said first transfer register in said allocating step.  
   
   
       31 . The method of driving a solid-state image-pickup device according to  claim 30 , further comprising a second allocating step in which signal charges are transferred from the third transfer register to the second transfer register prior to said driving step, wherein at least two-phase transfer clocks are utilized in said second transfer register, and a signal driving said third transfer register and said two-phase transfer clocks determine which signal charges are transferred from said third transfer register to said second transfer register in said second allocating step.