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1.1 Prior art In the past , multispectralimaging instruments were generally custom designed to suite a particular requirement or need. This meant that the imagers were either of simplistic single function or they were complex, expensive, and customized. In the Eighties ,withthe development of CCD technology ,manyof the existing film based systems were transitioning to electro-optical systems.One driving reason for the interest in electrooptical systems was the near real-time acquisition. A second key driver was the lower material and logistics costs. 1.2 New technology Now ,theadvent of High Definition television in the United States requiring high resolution and color accurate imaging and display devices ,hasprompted new technological developments in CCD imagers1'2,high data rate digital recording3' and display devices capable of displaying 2 million pixels with 24 bit color.High Definition (HD)has pushed the technological envelope enabling high resolution imaging technology to enter the domain of the multispectral reconnaissance community. 1.3 Application to reconnaissance Until recently most of the reconnaissance cameras had to be custom developed due to the lack of existing technology to meet the requirements of the application. Typically the cost of focal plane development was prohibitively expensive, costing 2-15 million dollars for simple linear arrays; therefore, only few varieties were developed. High definition technology offers to reconnaissance camera designers visible focal planes 1920 x 1036 pixels with frame rates of 30 frames/sec ,small 3 color prism /CCD optical blocks for multispectral capability, dynamic range of 10 f/stops or 72 db, and a sensitivity of f/8 at 2000 lux. On the recording side, High Definition technology offers 1.2 GBit/sec digital recording devices with a 63 minute capacity or 5400 frame write-once laser disc recorders. HD offers two unique capabilities to reconnaissance namely : (1) Color (multispectral) and (2) Real-time ( adding temporal to spatial information). HD also provides a family of compatible imaging, recording and display devices that are cost effective.
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