Conventional DC iris lenses purely adjust the aperture size to control the amount of light entering into cameras. However there are adverse effect on the video if the aperture is too widely opened or too small. These effects become more noticeable as the sensor resolution or the size of the image sensor increases.
The depth of field of the video becomes shallow if the aperture is widely opened. So if some objects are closer to the cameras than the others, small parts on the video would inevitably become out of focus. On the contrary, diffraction on the light would occur when entering into the camera if the aperture is too small. So some portions of the video would become blurry.
The letter “P” in P-iris stands for “precision”. P-Iris is a new mechanism for controlling the brightness of the video. It manipulates multiple parameters, including aperture size, exposure time, electronic amplification, of a camera in order to obtain the optimum video quality against the variation in the lighting condition. The mechanism would firstly set the lens aperture at the optimum opening size to ensure maximum clarity. Then the camera would adjust the exposure time and electronic amplification in order to achieve the optimum brightness.
In situations when the preferred iris position and the camera’s electronic processing capabilities cannot adequately correct the brightness, the P-Iris mechanism will automatically adjust the aperture size and repeat the process again until the optimum video output is achieved.
Currently all WAMA 5M pixels IP camera models adopt P-Iris technology to ensure delivering the best quality video under all kinds of lighting situations.