Image Access bookeye 3, Инструкция по сборке

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A.1.2 Device Location
A.1.2.1 Environment
Choose a location that complies with the limits of temperature and humidity. Refer to
chapter D.2 for detailed environmental specification.
A.1.2.2 Ambient Light
The location should have a controlled ambient light situation. Light scenarios to avoid are
direct sunlight, spot light from light beams, light sources that cause sharp shadows on the
scanning bed, high levels of ambient light and varying light conditions.
The Bookeye® 3 scanner is an open system with a built-in high quality light source. Open
system means, that the ambient light is added to the light seen by the camera.
The recommended location for the Bookeye® 3 scanner:
•
Is not exposed to daylight.
•
Is evenly illuminated from the ceiling with fluorescent lamps with electronic
ballasts. The light intensity measured on the book cradles should be 300 lux or
less.
•
The light should not cause any shadows; therefore the variation of the intensity
across the scan area should be kept below 20%.
If the fluorescent lamps are powered by non electronic ballasts, they will produce a flicker
twice the frequency of the main power supply (100Hz or 120Hz). If the intensity of this
light becomes too high, vertical stripes of even distances of approx. 8-12 pixels will be
visible on the scan.
Direct sunlight will vary over the day and will result in overexposed images. Sunlight also
can produce sharp shadows.
Light beams from spot lights will also produce sharp shadows. They emit (in most cases)
a high level of infrared light. Infrared light is not visible to the human eye but not the
camera. The light source of the Bookeye® 3 scanner itself has no infrared content at all.
The advantage is that the scanner does not have an image quality degrading infrared
filter. Too much infrared content will result in overexposure.
The Bookeye® 3 scanner has an integrated “White Balance” function. This function will
compensate the ambient light influences. Therefore it is recommended to perform the
“White Balance” function when the ambient light scenario has been changed.
Page 16 Setup and Assembly Manual