All flashlights have a reflector giving a wide enough beam of light. But if you want a point — for example, the light pointer of the lecturer? Narrow beam, as if from hidden lamps in detective films, will Give a simple nozzle. For its production will need a plastic Cup suitable diameter and lens from diascope to view the slides. In the bottom of the Cup making the hole, on which the acetone is glued to the plastic rim of the eyepiece.
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