| 摘要 |
A new and improved line scan camera achieves the proper framing of the image field of view by using a first test card to calibrate the true bottom and leading edge portions of the test card which simulate the true bottom and leading portions of an article being scanned or photographed. Still further, the architecture of the electronic chip incorporated within the charge coupled device (CCD) of the camera effectively divides the linear array of pixels into a plurality of channels, and amplifier gain and black offset adjustments are made with respect to exposure levels, characteristic of the pixels disposed at the channel boundaries, under different degrees of input whiteness signals applied to a test card of a predetermined color shade, so as to achieve channel-to-channel seam matching. Subsequently, correction factors are effectively superimposed upon substantially all of the exposure levels characteristic of substantially all of the pixels comprising the line scan of the line scan camera such that true uniform exposure levels are in fact achieved.
|
