Fig. 3 Widefield confocal scanning laser MACROscope1

A widefield scanning-beam confocal imaging system (MACROscope1) is shown in Fig. 3. Instruments based on this design behave very much like confocal scanning laser microscopes. All of the confocal scanning laser microscopy (CSLM) contrast mechanisms are available,

Fig. 2 Infinity-corrected confocal microscope.

but these instruments have a field of view that is about 20 times larger than a scanning laser microscope using a microscope objective with the same numerical aperture as the laser scan lens.

In Fig. 3, a beam expander expands the laser beam to match the diameter of the entrance pupil of the laser scan lens. This beam is reflected by a beam splitter toward a computer-controlled scanning mirror, situated at the entrance pupil position of a telecentric f-theta laser scan lens. The laser scan lens focuses the scanning beam on the specimen (usually on a microscope slide), which is mounted on a scanning stage. The scanning stage moves slowly in a direction perpendicular to the direction of the beam scan, such that the focused laser spot performs a raster scan across the specimen. Light reflected from, or fluorescence emitted by the specimen, is collected by the laser scan lens, passes back through the beam splitter, and is focused on a confocal pinhole in front of the detector. Light passing through the pinhole is detected. Photomultiplier tubes are often used as detectors because of their high speed, high sensitivity, and large dynamic range.

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Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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