Inspection Apparatus and Method for Producing Image for Inspection

Abstract

In order to obtain a quality image without deterioration owing to radiation noise in inspection using the optical video camera in high radiation environment, an inspection apparatus is formed of an image pick-up unit, an image obtaining unit which fetches a video image that contains a signal (noise) that is substantially independent of each frame obtained by the image pick-up unit, a local alignment unit which locally aligns frames with different time phases for forming the image fetched by the image obtaining unit, a frame synthesizing unit which synthesizes the plurality of frames aligned by the local alignment unit for generating a synthesis frame with an SN ratio higher than the SN ratio of the frame before frame synthesis, and an image output unit for displaying or recording the image formed of the synthesis frame generated by the frame synthesizing unit.

What is claimed is: 
     
         1 . An inspection apparatus comprising:
 an image pick-up unit provided with an optical video camera;   an image obtaining unit which fetches a video image that contains a signal (noise) that is substantially independent of each frame of the video image obtained by picking up a video image of an inspection object by the image pick-up unit;   a local alignment unit which locally aligns a plurality of frames of the video image with different time phases;   a frame synthesizing unit which synthesizes the plurality of frames of the video image aligned by the local alignment unit for generating an image formed of the synthesized frames with an SN ratio higher than the SN ratio of each of the frames before frame synthesis; and   an image output unit for displaying or recording an image formed of the synthesis frame generated by the frame synthesizing unit,   a noise amount measurement unit which measures an amount of the signal (noise) substantially independent of the respective frames of the video image fetched from the optical video camera of the image pick-up unit in the image obtaining unit; and   a processing parameter change unit which changes a processing parameter for processing the frame of the video image or the synthesized frames in the local alignment unit, the frame synthesizing unit or the image output unit in accordance with the amount of the signal as noise substantially independent of the respective frames of the video image, which is measured by the noise amount measurement unit.   
     
     
         2 . The inspection apparatus according to  claim 1 , wherein the noise amount measurement unit measures the amount of the signal as noise which is substantially independent of the respective frames using the frames of the video image before and after synthesizing. 
     
     
         3 . The inspection apparatus according to  claim 1 , wherein the processing parameter change unit changes one of an image display rate and a recording rate for processing the frame of the video image or the synthesis frame in the local alignment unit, the frame synthesizing unit, or the image output unit. 
     
     
         4 . The inspection apparatus according to  claim 1 , wherein the processing parameter change unit changes number of frames used for the frame synthesis in the local alignment unit or the frame synthesizing unit. 
     
     
         5 . The inspection apparatus according to  claim 1 , wherein the processing parameter change unit changes weights of the frame synthesis in the frame synthesizing unit.