Auto-iris lens
One of the most important requirements for the realization of a simple machine vision system is stable illumination. If this cannot be guaranteed, an auto-iris lens may be helpful. Like the human eye, it adapts itself to environmental illumination, by opening and closing its iris.
Outdoor surveillance cameras are fitted with auto-iris lenses by default. These lenses are controlled directly by the surveillance camera. In machine vision applications, this direct coupling is seldom acceptable: Imagine, a thermometer adapts itself automatically to the ambient temperature.
Thus, in the context of industrial USB cameras, FireWire cameras or GigE cameras, the application software should be responsible for the auto-iris control. This way, the software always "knows" the iris setting used to take the respective image. The Imaging Source offers industrial cameras with an integrated, motorized iris - the zoom cameras.
