Posted to News on 4th Aug 2010, 21:27
Dual CCD camera suits scenes with extremes of brightness
Now available from Stemmer Imaging, the new JAI AD-081GE dual CCD camera provides independent shutter/gain control for each CCD, enabling the camera to capture details in scenes with a wide variation of light intensities, which results in enhanced dynamic range and extremely versatile imaging. This new camera is fully compliant with the GigE Vision and GeniCam standards, and features built-in image fusion capabilities for merging the outputs from the two sensors.
Independent control of the shutter and gain for each sensor not only enables the camera to be configured for high dynamic range (HDR) applications, but also makes it particularly suitable for applications where two extremes of light levels may need to be imaged; each sensor can be set to give the optimum sensitivity for a particular light level. Applications include indoor/outdoor or day/night surveillance, traffic applications, welding, glass inspection, or applications involving lasers or laser grids.
The image fusion routine built into the JAI SDK features three selectable HDR modes that can automatically produce a high dynamic range output without any post-processing, with the user simply setting the exposure value of each of the CCDs. In addition, there are specialised HDR functions and a sample application included in the SDK and Control Tool software. This enables HDR processing to be offloaded to a host computer, either to the sample application supplied, or to a customised application built from the HDR functions to suit the specific application.
Dual CCD accuracy
The two prism-mounted monochrome 1/3inch CCDs (1024 x 768 pixel resolution) with monochrome sensitivity in the visible spectrum are aligned to within one-quarter pixel accuracy. This ensures that both sensors have the same field of view and that there are no ghosting or parallax issues when imaging moving objects or scenes.
In addition to the HDR mode, the AD-081GE features a new High S/N mode that automatically averages the video information from the two CCDs to produce a single image with a significantly lower noise component than a typical single-CCD image. This is achieved by interleaving the images from the two CCDs into a single output stream. The result of this is that the camera can operate at an effective 60fps without any increase in the clock frequency of the camera, thereby providing a significantly less noisy image.
