Digital pathology via whole-slide imaging (WSI) systems has recently been approved for the primary diagnostic use in the US. Acquiring whole-slide images with spectral information at each pixel permits the use of multiplexed antibody labeling and allow for the measurement of cellularly resolved chemical information. Here, we report the development of a high-throughput terapixel hyperspectral WSI system using prism-based slit-array dispersion. We demonstrate a slit-array detection scheme for absorption-based measurements and a slit-array projection scheme for fluorescence-based measurements. The spectral resolution and spectral range in the reported schemes can be adjusted by changing the orientation of the slit-array mask. We use our system to acquire 74 5-megapixel brightfield images at different wavelengths in ∼1 s, corresponding to a throughput of 0.375 gigapixels / s. A terapixel whole-slide spatial–spectral data cube can be obtained in ∼45 min. The reported system is compatible with existing WSI systems and can be developed as an add-on module for whole-slide spectral imaging. It may find broad applications in high-throughput chemical imaging with multiple antibody labeling. The use of slit array for structured illumination may also provide insights for developing high-throughput hyperspectral confocal imaging systems.
Scanning confocal microscopy is a standard choice for many fluorescence imaging applications in basic biomedical research. It is able to produce optically sectioned images and provide acquisition versatility to address many samples and application demands. However, scanning a focused point across the specimen limits the speed of image acquisition. As a result, scanning confocal microscope only works well with stationary samples. Researchers have performed parallel confocal scanning using digital-micromirror-device (DMD), which was used to project a scanning multi-point pattern across the sample. The DMD based parallel confocal systems increase the imaging speed while maintaining the optical sectioning ability. In this paper, we report the development of an add-on kit for high-speed and low-cost confocal microscopy. By adapting this add-on kit to an existing regular microscope, one can convert it into a confocal microscope without significant hardware modifications. Compared with current DMD-based implementations, the reported approach is able to recover multiple layers along the z axis simultaneously. It may find applications in wafer inspection and 3D metrology of semiconductor circuit. The dissemination of the proposed add-on kit under $1000 budget could also lead to new types of experimental designs for biological research labs, e.g., cytology analysis in cell culture experiments, genetic studies on multicellular organisms, pharmaceutical drug profiling, RNA interference studies, investigation of microbial communities in environmental systems, and etc.
A novel method for trace gas detection is presented and developed. A fiber laser with a gas cell in the loop is
constructed, whose output spectrum is changed with the concentration of the gas e.g., acetylene. As the
concentration of acetylene changes from 0 to 100% under a standard atmosphere, the peak of output spectrum
shifts 0.03nm. It means to our system, a resolution of 3.75 KHz in light frequency change will lead to a
sensitivity of ppm in gas concentration measurement, which makes it a economical and promising technique to
measure low density gas.