Optical sheet inspection system

A system for optically inspecting high velocity individual flat sheets having scrolled and unscrolled edges in a production line for defects, each of said individual flat sheets being at spaced locations from each other and having a first dimension in the direction of movement and a second dimension perpendicular thereto, said system comprising:

• a formed viewing window, said formed viewing window having a length perpendicular to said direction of movement and a width greater than said second dimension of each said individual flat sheet;
• means receiving said individual flat sheets from said production line at said spaced locations for delivering each of said sheets over said formed viewing window, at said high velocity,
• means for uniformly and continuously illuminating the surface of each said individual flat sheet along said length of said formed viewing window with high intensity diffused light as each said individual flat sheet is delivered over said formed viewing window by said delivering means,
• means receiving the reflected high intensity diffused light from the surface of each individual flat sheet for capturing a video image of each line across said length of each of said individual flat sheet independent of the velocity of each said individual flat sheet, each said line being one pixel wide and a sufficient number of pixels in length to equal said second dimension of each said individual flat sheet, wherein said capturing means is further capable of capturing said video images even if the delivered individual flat sheet over said formed viewing window has a skewness less than a predetermined acceptable value,
• means connected to said capturing means for storing an electronic image of each said individual flat sheet, said electronic image comprising a sufficient number of said captured lines to equal said first dimension of each said individual flat sheet, wherein said storing means is first capable of determining the edge of the first captured video line image and then is capable of storing all subsequent captured video line images adjusted to said determined edge so that any scrolled edge of said individual flat sheet is transformed into a straight edge in the corresponding electronic image thereby enabling the analysis of any defects present in said scrolled edge,
• means connected to said storing means for analyzing said stored electronic image of each said individual flat sheet for defects, said analyzing means issuing a reject signal when a defect is detected in said stored electronic image, and
• means receptive of said reject signal for removing the individual flat sheet corresponding to said reject signal from said production line.

A system for optically inspecting high velocity individual flat sheets having scrolled and unscrolled edges in a production line for defects, each of said individual flat sheets being at spaced locations from each other and having a first dimension in the direction of movement and a second dimension perpendicular thereto, said system comprising:

• a formed viewing window, said formed viewing window having a length perpendicular to said direction of movement and a width greater than said second dimension of each said individual flat sheet;
• means receiving said individual flat sheets from said production line at said spaced locations for delivering each of said sheets over said formed viewing window at said high velocity,
• means for uniformly and continuously illuminating the surface of each said individual flat sheet along said length of said formed viewing window with high intensity diffused light as each said individual flat sheet is delivered over said formed viewing window by said delivering means,
• means receiving the reflected high intensity diffused light from the surface of each individual flat sheet for capturing a video image of each line across said length of each of said individual flat sheet independent of the velocity of each said individual flat sheet, each said line being one pixel wide and a sufficient number of pixels in length to equal said second dimension of each said individual flat sheet,
• means connected to said capturing means for storing an electronic image of each said individual flat sheet, said electronic image comprising a sufficient number of said captured lines to equal said first dimension of each said individual flat sheet, wherein said storing means is first capable of determining the edge of the first captured video line image and then is capable of storing all subsequent captured video line images adjusted to said determined edge so that any scrolled edge of said individual flat sheet is transformed into a straight edge in the corresponding electronic image thereby enabling the analysis of any defects present in said scrolled edge,
• means connected to said storing means for analyzing said stored electronic image of each said individual flat sheet for defects, said analyzing means issuing a reject signal when a defect is detected in said stored electronic image, and
• means receptive of said reject signal for removing the individual flat sheet corresponding to said reject signal from said production line.

A system for optically inspecting high velocity individual flat sheets having scrolled and unscrolled edges in a production line for defects, each of said individual flat sheets being at spaced locations from each other and having a first dimension in the direction of movement and a second dimension perpendicular thereto, said system comprising:

• means for uniformly and continuously illuminating a portion of the surface of each said individual flat sheet along said second dimension with high intensity diffused light,
• means receiving the reflected high intensity diffused light from said portion of each individual flat sheet for capturing a video image of a line across said second dimension of said individual flat sheet, each said line being one pixel wide and a sufficient number of pixels in length to equal said second dimension of each said individual flat sheet, each pixel having a grey level value corresponding to the reflected high intensity diffused light from an area on said individual flat sheet,
• means connected to said capturing means for storing an electronic image of each said individual flat sheet, said electronic image comprising said sufficient number of pixels and a sufficient number of said captured lines to equal said first dimension of each said individual flat sheet,
• means for determining the transition edge of each captured video line image by issuing an edge signal, said storing means being capable of storing each captured video line image at the same starting address in response to said edge signal so that any edge configuration of said individual flat sheet is transformed into a straight edge in the corresponding electronic image thereby enabling the analysis of any defects present in said scrolled edge, and
• means connected to said storing means for analyzing the grey levels of pixels in said stored electronic image of each said individual flat sheet for defects, said analyzing means issuing a reject signal when a defect is detected in said stored electronic image.