Spectral microscopy has ability to detect broadband fluorescence signals which are useful in case of studying interactions and phenomena between biological samples. Recently, commercial devices are combining with the confocal microscope so to enhance lateral resolution and to have axial direction discernment. Also Acousto-Optic Tunable Filter(AOTF) is used instead of using multiple-dichroic mirrors to divide excitation and emission signals to maximize light efficiency. In addition, AOTF used in spectral microscopy have many merits, that are very fast switching speed and high resolution in wavelength selection. However AOTF uses the principle of acousto-optic interactions in a birefringent material, the excitation light interacts with appropriate radio frequency signal so that it is diffracted to 1 or -1 order beam-path. Also, the fluorescence signals from the sample propagate in 0 order beam-path with different angles according to the wavelength and its polarization state. In this paper, the confocal-spectral microscopy is proposed with the novel spectrometer design having wavelength-scanning galvano mirror. It makes possible to detect broadband(480~700nm) fluorescence signal by single point detector(PMT) instead of CCD pixel arrays. For this purpose, some optical elements are appropriately designed. In order to amplify dispersion angle of fluorescence signal, prism is used. And relay lens are designed to match the signals with diameter of wavelength-scanning gavano mirror. Also a birefringent material, calcite is used to compensate polarization effect.
The proposed spectral confocal microscopy with unique spectrometer body has many advantages in comparison with commercial devices. In terms of detection method, it can be easily applied to other imaging modalities. Hence this system will be adapted in many applications.
