Terminology: Difference between revisions
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;direct drive: When the batteries power the LED directly without any regulation in the driver, or without a driver at all. See article [[Driver]]. | ;direct drive: When the batteries power the LED directly without any regulation in the driver, or without a driver at all. See article [[Driver]]. | ||
;<span id="DMM">DMM</span>: Digital MultiMeter. Measures volts, amps, ohms, etc. You can spend anywhere from a few dollars to several hundred on a DMM. For flashlights it is helpful to be able to measure current (amps) in addition to volts. | |||
;donut hole: a dark spot in the center of the flashlight beam. This is a common problem with multi-die emitters (can also appear as a plus-sign in the beam reflecting the layout of the 4 dice) but can also be the result of a poorly matched reflector. | ;donut hole: a dark spot in the center of the flashlight beam. This is a common problem with multi-die emitters (can also appear as a plus-sign in the beam reflecting the layout of the 4 dice) but can also be the result of a poorly matched reflector. | ||