27 Jul 2010
NIR imaging allows features below the surface of an object to be viewed, thus providing different information to the RGB channels and revealing imperfections that the human eye cannot see. Linescan applications include: fruit and vegetable sorting, food inspection, web inspection (wood, textile, paper, glass), tiles inspection, 2D and 3D print inspection, surface inspection of flat panels/displays and PCB inspection.
The camera’s unique dichroic prism-block technology splits the incoming light into the 4 non-overlapping spectral band onto 4 separate CCD sensors with perfect pixel to pixel alignment, ensuring that the R, G, B and NIR pixels see exactly the same point on the object at all times. This produces high quality and perfectly aligned line scan images independent of the viewing angle to the inspected object, independent of variations on conveyer belt speed and independent of whether the object has a wavy or curved texture. This precise image alignment and colour registration makes inspection systems featuring these cameras faster and easier for end-users to setup, calibrate and maintain.
Each of the four CCD sensors provides 2048 linear pixels with a pixel size of 14 ?m x 14 ?m square. The camera runs at a maximum scan rate of 19048 lines per second with a 40 MHz pixel clock, delivering a high signal-to-noise ratio of 58dB. Built-in pre-processing functions include flat-field correction and gamma/gain correction, which, together with the electronic shutter can be set individually for the red, blue, green and NIR channels. The gamma/gain correction function also allows full advantage to be taken of the sensors’ dynamic range to optimize the image.