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Author Topic: Fast acting gate for laser?  (Read 268 times)
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Got a project where I'd like to turn a laser on and off somewhat quickly, on the order of turning the laser on for as little as 20ms to upwards of 1s.

with the laser controlled by a mosfet; it appears the laser takes much longer to turn off and on that trying to turn it on for most intervals in this range results in no output.

so I'm thinking I may just turn the laser on, put a bigger heatsink on it, and find a fast way to block and unblock the beam. Not a burning laser so that shouldn't be an issue.

any ideas? Stepper motor or servo to whip a cover in and out of place?
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Just thinking out load but maybe an LCD screen?
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Dubuque, Iowa, USA
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20ms is only 50Hz. Any mosfet can switch much much more quickly than that. Your problem lies elsewhere, probably in the circuitry for the laser module?
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Hofstadter's Law: It always takes longer than you expect, even when you take into account Hofstadter's Law.
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I agree - the laser module probably contains a capacitor, which is powering the laser for some time after you remove power to it. Preferably, tap into the module's electronics rather than just turning the power on/off.
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