Akiko HIRAI, Machiko HASHIMOTO,^* Kazuyoshi ITOH and Yoshiki ICHIOKA

Graduate School of Engineering, Osaka University, Yamadaoka 2-1, Suita, Osaka, 565 Japan

(Received October 14, 1996; Accepted December 18, 1996)

A multichannel spectral imaging system consisting of dichroic mirrors is proposed. The system is expected to have the highest signal-to-noise ratio (SNR) because of the largest optical throughput realized by the multichannel configurations for both imaging and spectrometry. A multichannel spectral imaging system with eight spectral bands was designed by the evolutionary algorithms and then fabricated. The SNR is studied and compared experimentally with those of other fast spectral imaging techniques. A time-sequence of spectral images of a super-continuum light beam is measured using the present system. The number of spectral channels of the system is limited chiefly by the difficulty in designing the arrangement of dichroic mirrors and the optical performance of those mirrors. These limitations restrict the number of spectral channels to approximately 16 at present.

Key words : spectral imaging, multichannel measurement, dichroic mirror, fast phenomena, evolutionary algorithms, evolution strategy, genetic algorithms, super-continuum light

*Present address: Railway Information Systems Co., Ltd., Hikari-cho 1-47-4, Kokubunji, Tokyo, 185 Japan.