A 256 x 192 pixel field emitter array (FEA) image sensor with a highly sensitive high-gain avalanche rushing amorphous photoconductor (HARP) target was fabricated and tested as a step toward the development of a practical image sensor for ultrahigh sensitivity and ultrahigh-definition compact TV cameras. The experimental results showed that the prototype had an adequate resolution corresponding to the spot size of the scanning electrons on the HARP target which was estimated by the simulation. The prototype also had a wide dynamic range and high sensitivity, demonstrating its potential as a next generation practical image sensor and offering new application of FEAs. (C) 2004 American Vacuum Society.