Proceedings Article | 16 November 2010
Proc. SPIE. 7857, Multispectral, Hyperspectral, and Ultraspectral Remote Sensing Technology, Techniques, and Applications III
KEYWORDS: Diffraction, Imaging systems, Cameras, Control systems, CCD cameras, Transducers, Spectral resolution, Acoustics, Acousto-optics, Radio frequency circuits
One of the advantages of acousto-optic tunable filter (AOTF) is its spectral selectivity, not only central
wavelength, but also bandwidth and passband form, can be controlled by RF signals, which provides us the
opportunity to develop a more flexible hyper-spectral imager. Traditional hyper-spectral imagers collect
hyper-spectral images with certain spectral resolutions and spectral sampling intervals, which means a huge
amount of data and low data efficiency. So, a more flexible device to meet different applications with less but
more effective data is an attractive idea. The idea is brought out this year in SITP, CAS. A custom-made AOTF
which can endure higher power is adopted to realize such a hyper-spectral imager. A RF generating system is
designed to produce and control 12 channels of RF signals independently, and a PC is used to control the system
and record the digital images obtained by a CCD camera. If the controlling RF frequencies are close enough to
each other, the consecutive output passbands will combine into one wider band, and the programmable spectral
resolution and passband form are available. If the RF signals are discrete, the image of several discrete spectral
bands combination which can simply be treated as a fused image is available. In this paper, the theory and
structure of the system is set out, some important details of design principle are introduced, some of the original
test results and a few of experimental images are showed.
