Image sensing apparatus and image sensing method, X-ray photographing system and its control method

Abstract

Since the duration of an idling drive period is not defined (not specified) in practical use, T 1 is set to be longer than that in a normal photographing operation to make idling-dedicated idle read frames Fi in which the ON time of a TFT ( 82 ) is shorter than the normal read drive frame, so as to minimize read operations that impose a heavy load on a photodetector array ( 58 ) (especially, the TFT ( 82 )).

What is claimed is:  
     
         1 . An image sensing apparatus comprising: 
 an image sensing region for sensing an object image; and    a drive circuit for resetting said image sensing region at a first time interval during a first period before an image sensing operation, and for resetting said image sensing region at a second time interval during a second period prior to the first period,    wherein the first time interval is different from the second time interval.    
     
     
         2 . The apparatus according to  claim 1 , wherein the second time interval is longer than the first time interval.  
     
     
         3 . An image sensing apparatus comprising: 
 an image sensing region for sensing an object image; and    a drive circuit for resetting said image sensing region at a predetermined interval during a first time period before an image sensing operation, and for resetting said image sensing region at a predetermined interval during a second time period prior to the first time period,    wherein the first time period is different from the second time period.    
     
     
         4 . The apparatus according to  claim 3 , wherein the second time period is shorter than the first time period.  
     
     
         5 . The apparatus according to  claim 1 , wherein said image sensing apparatus senses the object image by radiation exposure, and the first period is generated in response to a radiation exposure request before the radiation exposure.  
     
     
         6 . The apparatus according to  claim 3 , wherein said image sensing apparatus senses the object image by radiation exposure, and the first time period starts in response to a radiation exposure request before the radiation exposure.  
     
     
         7 . The apparatus according to  claim 1 , wherein said image sensing apparatus senses the object image by radiation exposure, and further comprises a control circuit which controls to start radiation exposure upon completion of the reset operation when a radiation exposure request before the radiation exposure is received during the reset operation.  
     
     
         8 . The apparatus according to  claim 3 , wherein said image sensing apparatus senses the object image by radiation exposure, and further comprises a control circuit which controls to start radiation exposure upon completion of the reset operation when a radiation exposure request before the radiation exposure is received during the reset operation.  
     
     
         9 . The apparatus according to  claim 1 , wherein said drive means reads an image charge signal in a predetermined column direction, and drives for each predetermined row at a predetermined period.  
     
     
         10 . An image sensing method comprising the step of: 
 resetting an image sensing region used to sense an object image at a first time interval during a first period before an image sensing operation, and resetting the image sensing region at a second time interval during a second period prior to the first period,    wherein the first time interval is different from the second time interval.    
     
     
         11 . An image sensing method comprising the step of: 
 resetting an image sensing region used to sense an object image at a predetermined interval during a first time period before an image sensing operation, and resetting the image sensing region at a predetermined interval during a second time period prior to the first time period,    wherein the first time period is different from the second time period.    
     
     
         12 . A computer-readable storage medium that stores a program for making a computer function as means which form an image sensing apparatus cited in  claim 1 .  
     
     
         13 . A computer-readable storage medium that stores a program for making a computer execute the processing step of an image sensing method cited in  claim 10 .  
     
     
         14 . A program for making a computer function as means which form an image sensing apparatus cited in  claim 1 .  
     
     
         15 . A program for making a computer execute the processing step of an image sensing method cited in  claim 10 .  
     
     
         16 . A radiography system which comprises a detector for detecting radiation generated by a radiation generation device, and a detector controller for initializing said detector at a predetermined timing, and controlling said detector, and takes a radiation image on the basis of the radiation detected by said detector, 
 wherein said detector controller comprises: 
 storage means for acquiring and storing a time period from when initialization of said detector starts until a radiation irradiation request signal is received; and  
 instruction means for, when the radiation irradiation request signal is received during an initialization process of said detector, instructing to execute a wait process for the stored time period after the initialization process, and  
 upon completion of the wait process by said instruction means, a radiography permission signal is sent to said radiation generation device.  
   
     
     
         17 . A radiography system which comprises a detector for detecting radiation generated by a radiation generation device, and a detector controller for initializing said detector at a predetermined timing, and controlling said detector, and takes a radiation image on the basis of the radiation detected by said detector, 
 wherein when a radiation irradiation request signal is received during an initialization process of said detector, said detector controller sends a radiography permission signal to said radiation generation device after completion of the initialization process.    
     
     
         18 . A method of controlling a radiography system which comprises a detector for detecting radiation generated by a radiation generation device, and a detector controller for initializing said detector at a predetermined timing, and controlling said detector, and takes a radiation image on the basis of the radiation detected by said detector, 
 wherein said detector controller acquires and stores a time period from when initialization of said detector starts until a radiation irradiation request signal is received,    when said detector controller receives the radiation irradiation request signal during an initialization process of said detector, said detector controller instructs to execute a wait process for the stored time period after the initialization process, and    said detector controller sends a radiography permission signal to said radiation generation device upon completion of the wait process based on the instruction.    
     
     
         19 . A method of controlling a radiography system which comprises a detector for detecting radiation generated by a radiation generation device, and a detector controller for initializing said detector at a predetermined timing, and controlling said detector, and takes a radiation image on the basis of the radiation detected by said detector, 
 wherein when a radiation irradiation request signal is received during an initialization process of said detector, said detector controller sends a radiography permission signal to said radiation generation device after completion of the initialization process.    
     
     
         20 . A program code for making an information processing apparatus execute a method of controlling a radiography system cited in  claim 18  when said program code is loaded by said information processing apparatus.  
     
     
         21 . A computer-readable storage medium which stores a program code cited in claim  20 .