1mW laser driver and safety

[Elektro]

Hello

I need to find a laser driver circuit that can drive a laser diod
emitting 1 mW. The laser will be driven with 70 kHz and 50% duty cycle
(that is a peak of 2 mW).

The laser power should be regulated with a DA-converter, preferably
adjustable from 0 to about 1 mW.

And I need some laser safety that shuts down the laser in case of
malfunction. Maby some kind of watch dog timer circuit.

So what options are there (preferably IC-circuits)?

 

[Mark X]

Try alt.lasers

 

[Phil Hobbs]

Hello

I need to find a laser driver circuit that can drive a laser diod
emitting 1 mW. The laser will be driven with 70 kHz and 50% duty cycle
(that is a peak of 2 mW).

The laser power should be regulated with a DA-converter, preferably
adjustable from 0 to about 1 mW.

And I need some laser safety that shuts down the laser in case of
malfunction. Maby some kind of watch dog timer circuit.

So what options are there (preferably IC-circuits)?

What wavelength? A 2 mW visible laser is class 2, so you might not need
an interlock. As for the watchdog, you can use a retriggerable
monostable, but you'd have to have something to drive it with, e.g. a
spare MCU pin.

Cheers,

Phil Hobbs

 

[Don Klipstein]

What wavelength? A 2 mW visible laser is class 2, so you might not need
an interlock. As for the watchdog, you can use a retriggerable
monostable, but you'd have to have something to drive it with, e.g. a
spare MCU pin.

Visible lasers 1 to 4.999 milliwatts are Class IIIa. Visible lasers .4
microwatt to .999 milliwatt are Class II. At least in the USA - 21 CFR
1040.10 and .11.

Laser pointers legally sold in the USA are in one of these two classes -
usually Class IIIa. (Britain limits those to Class II.) These do not
legally require interlocks, keys, safety goggles, etc.

The regulations beyond product labeling and certification kick in when
you hit Class IIIb - 5 to 499.9 milliwatts. Although workplaces and
schools can have their own safety rules for Class IIIa and Class II
lasers, such as a requirement to wear goggles, etc.

- Don Klipstein ([email protected])

 

[Phil Hobbs]

Visible lasers 1 to 4.999 milliwatts are Class IIIa. Visible lasers .4
microwatt to .999 milliwatt are Class II. At least in the USA - 21 CFR
1040.10 and .11.

Laser pointers legally sold in the USA are in one of these two classes -
usually Class IIIa. (Britain limits those to Class II.) These do not
legally require interlocks, keys, safety goggles, etc.

The regulations beyond product labeling and certification kick in when
you hit Class IIIb - 5 to 499.9 milliwatts. Although workplaces and
schools can have their own safety rules for Class IIIa and Class II
lasers, such as a requirement to wear goggles, etc.

- Don Klipstein ([email protected])

Must have changed. I have a drawer full of 2 mW "Class 2" HeNe lasers.

Cheers,

Phil Hobbs