Multiplexed Acousto-Optic Tunable Filter (AOTF) Spectral Imaging Microscopy
Proceeding SPIE 2173, Image Acquisition and Scientific Imaging Systems
In contrast to existing methodologies employed for multispectral imaging based on filter wheels, prisms or gratings, the acousto-optic tunable filter (AOTF) provides significant advantages. The AOTF is digitally accessible providing wavelength selection and rapid optical switching in a compact instrument. In addition, AOTFs can be employed as multiplexed polychromators in which several wavelengths are tuned at the same time by injecting multiple rf signals into the AOTF simultaneously. We apply spectral multiplexing for Raman microscopy in which the integrated image on the CCD detector is the linear combination of scattered radiation corresponding to several vibrational modes. Hadamard transform mathematics govern the multiplexing sequence allowing efficient recovery of the spectrum. In this manner, the optical throughput of the AOTF is increased and spectral images can be collected rapidly.
Schaeberle, Michael D.; Turner, John F. II; and Treado, Patrick J., "Multiplexed Acousto-Optic Tunable Filter (AOTF) Spectral Imaging Microscopy" (1994). Chemistry Faculty Publications. 353.