Microscope Use
In microscopy the Barlow lens is used to increase working distance and decrease magnification. The lenses are "objective lenses" that are mounted in front of the microscope's last objective element. Standard lenses are 2× which decreases the working distance by half and increases the magnification, 0.75× which increases the working distance proportionally to the 0.75 and decreases the magnification similarly. A 0.5× would double the working distance and halve the magnification.
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