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Pete, Electronic Engineer
Category: Consumer Electronics
Satisfied Customers: 17289
Experience:  Over 16 years of experience installing and repairing electronics.
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Lasers- I need someone who is knowledgeable of lasers. Not

Customer Question

Lasers- I need someone who is knowledgeable of lasers. Not talking about atom smashing stuff. More like laser pointers. Need help in determining the best laser in voltage and amps that will still qualify as FDA 3a/3r radiation category.
Following that, need to build a circuit with the lasers, probably a transistor and a PIR.
Submitted: 1 year ago.
Category: Consumer Electronics
Expert:  Pete replied 1 year ago.

Hi there,

The Spyder 3 is the most powerful laser currently available that complies as FDA 3a/3r.

You can get one from

Customer: replied 1 year ago.
Checked with wickedlasers; not apparent on their website but they are checking. I'll get back with you.
Expert:  Pete replied 1 year ago.

Ok Bob, let me know how you get on or if I can be of any further assistance at all...


Customer: replied 1 year ago.
Alright, Pete, this is where I am going: My goal is to produce a commercial product. Part of it requires an inexpensive laser module with a red or green line with a 5-15 degree divergence that can be shown brightly through a window at 2 meters.MY contacts with China indicate that there are many choices - all of which are available in lots of 1000 in a range of $1 to $2 / piece --which is necessary for it to be economically marketable. That price is probably comparable to the retail price of a $8-$10 laser pointer.
These lasers carry a power description of 5mW which, as you know, is the limit for FDA Category 3A or 3R.Now, because I am a neophyte in this discipline, it gets murky.I have no idea how quality expresses itself. A laser with what appears to be the same description varies in price from $8.00 to $250.00. Of course, I know that there are differences but I am in no way qualified to evaluate..Secondly, related subject: My recollection is that wattage=volt x amps. If so, and the products available show amps usage to be in the range of 30-60 milli amps, Doesn't that mean that the max voltage cannot exceed .08-.16 volts. Yet they all are documented to use 3-4.5 volts and 5mW. What am I missing??So that's where I am trying to go. I want to find this laser that complies with FDA Category 3A/3R limits, yet provides the brightest line beam in the range noted and is moderately priced. And how do I mix and match the voltage and current to get the best result. I know that they are available, I just don't know how to evaluate. Is this something that you can do?Bob
Customer: replied 1 year ago.
Pete, I haven't heard back from you. I am in need of someone with the skills and experience necessary to perform the above. If you can do the above,that would be good news and we can discuss it. Suggesting the $200 laser didn't help. if you don't have the experience to do the above, I understand completely.. Just let me know and I will look elsewhere. Thanks, Bob
Expert:  Pete replied 1 year ago.

Hi Bob,

Sorry for the delay in getting back to you.

I've been pondering this over the past couple of days but I cannot figure out a suitable solution for you, so I'm afraid I will have to opt out.