Abstract: A system and method utilizing two image sensors to simultaneously capture images of a FOV (field of view). The image sensors are arranged along the same optical path for viewing the FOV. The FOV is illuminated by an illuminator of a specific frequency band. An image is captured by the first image sensor which has a filter that passes at least a portion of the light of the frequency band of the illuminator. An image is captured by the second image sensor that has a filter to pass a band of frequencies adjacent to, but generally not including the frequency band of the illuminator. The images may be manipulated, for example, to provide enhanced performance and/or compensate for variables in the system. A processor subtracts the images to produce an image that represents light reflected back from the illuminator, excluding ambient light at the frequency of the illuminator.

Abstract: A system and method utilizing two image sensors to simultaneously capture images of a FOV (field of view). The image sensors are arranged along the same optical path for viewing the FOV. The FOV is illuminated by an illuminator of a specific frequency band. An image is captured by the first image sensor which has a filter that passes at least a portion of the light of the frequency band of the illuminator. An image is captured by the second image sensor that has a filter to pass a band of frequencies adjacent to, but generally not including the frequency band of the illuminator. The images may be manipulated, for example, to provide enhanced performance and/or compensate for variables in the system. A processor subtracts the images to produce an image that represents light reflected back from the illuminator, excluding ambient light at the frequency of the illuminator.

Abstract: The protector comprises two plastic moldings, fastened together to form a cone around a tree planted in a city avenue. The protector prevents salt from leaching down to the root-ball of the tree, and protects the tree from damage from snow and slush piled around the tree. The protectors are temporary, and the fasteners used can be removed by the authorities, but are of the vandal-resistant type.