Laser Diode Driver/Controller #85

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opened 2025-08-18 13:44:54 +00:00 by rahix · 1 comment

rahix commented

2025-08-18 13:44:54 +00:00

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For stable operation of a laser diode, its current and temperature need to be controlled very precisely. Commercial setups achieve this with two control loops:

A current controller (e.g. Thorlabs LDC205C) that optionally takes feedback from the laser diode's photodiode to run in constant power mode.
A temperature controller (e.g. Thorlabs TED200C) that is connected to a TEC (thermoelectric cooler = peltier device, Wikipedia) to control diode temperature with a stability of up to 0.002 °C. For temperature measurement, a 10k NTC thermistor is typically used.

For our purposes, we will probably need to build our own controller or replicate an existing design from someone else.

Resources

Sam's Laser FAQ — Diode Laser Power Supplies

For stable operation of a laser diode, its current and temperature need to be controlled very precisely. Commercial setups achieve this with two control loops: - A current controller (e.g. [Thorlabs LDC205C](https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=10&pn=LDC205C)) that optionally takes feedback from the laser diode's photodiode to run in constant power mode. - A temperature controller (e.g. [Thorlabs TED200C](https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=307&pn=TED200C)) that is connected to a TEC (thermoelectric cooler = peltier device, [Wikipedia](https://en.wikipedia.org/wiki/Thermoelectric_heat_pump)) to control diode temperature with a stability of up to 0.002 °C. For temperature measurement, a 10k NTC thermistor is typically used. For our purposes, we will probably need to build our own controller or replicate an existing design from someone else. #### Resources - [Sam's Laser FAQ — Diode Laser Power Supplies](https://www.lasersam.org/sam/laserdps.htm#dpstoc)

rahix added the

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Development

label 2025-08-18 13:44:54 +00:00

forgejo-actions commented

2025-08-18 13:44:58 +00:00

Partial Techtree

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    1["<a href='https://git.fa-fo.de/fafo/techtree/issues/87' target='_blank'>#87</a> | MISSING\n<i>Equipment</i>\n<b>Diode Laser</b>"]
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Digest: f295922e0a7390e8b54ae9506360d4a7e004dde124da1fcd27fecf787ae87da9; Last Updated: 2025-08-18 14:03:02

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rahix added a new dependency 2025-08-18 13:45:17 +00:00

#83 External Cavity Diode Laser (ECDL)

rahix added a new dependency 2025-08-18 14:03:03 +00:00

#87 Diode Laser

rahix removed a dependency 2025-08-18 14:03:31 +00:00

#83 External Cavity Diode Laser (ECDL)