<title>Cost-effective real-time multispectral digital video imaging</title>

Abstract

Multispectral imaging is an enabling technology for many emerging applications. To accomplish this, multiple images of a single field-of-view must be captured where each image is based on the reflected light in a specific spectral band. A number of issues must be addressed to achieve an effective imaging systems for multispectral applications. The design of a multispectral camera and numerous applications will be described. Applications include fruit and grain sorting, lumber grading, weed identification, precision farming, harsh environment monitoring, and advanced security. A family of multispectral cameras based on beam splitting optics and three CCD sensors have been developed. The family includes line scan and area array cameras utilizing common electronics and mechanical hardware, providing an economical solution to most multispectral applications. Up to five spectral bands within the 400 to 1100 nm sensitivity of the CCD sensor can be imaged with the area array camera and three bands within this same spectral range can be imaged with the line scan camera. The cameras acquire all of the spectral images simultaneously eliminating temporal discrepancies. The common optical aperture results in an identical field of view for each imaging channel. Output is available in analog and digital format. On-board signal processing enables real time image processing of the image data within the camera. Available image processing functions include thresholding, addition/subtraction of images, color space conversion, false color mapping, and area-of-interest.