Tetracam,

Tetracam produces the world's most efficient and most economical multi-spectral cameras and the software required to interpret what they see. On farms and ranches throughout the world, Tetracam systems monitor subtle changes in the visible and near-infrared radiation that plants reflect. Growers use this data to spot plants under stress, monitor plant growth or to perform dozens of other functions helpful in managing crops. Variations in the near-infrared indicate changes to vegetation long before any indications appear in the visible spectrum (refer to their System Application Notes for more information on the basic capabilities of their products).