# Needing Help On Lasers

I hope you can help me!

I’m going to categorize this into A) B) C)

Recently just bought a NUBM08 Nichia Laser Array and need to know how to get this boy working!

A)

So for this Spec Operating Voltage = Mid 34V & Max 38V Operating Current = Mid 3.1A & Max 3.5A

So how exactly do I get this working!? If you haven’t already watched; Styropyro has done this, Titled 40W Laser Shotgun on YouTube. So clearly it is possible.

From our Values above the wiring configuration would equal:

Series = 4.25V in each LD and 3.1A in each LD Parallel = 34V in each LD and 0.3875A in each LD

So from here I think its going to be a Series Configuration

What do I do next…

B)

Using an LM317 current Regulator Formula Resistor Required (Ohms) = 1.25V / Nominal LED Current (3.1A) = 0.4 Ohms

However I read that LM317’s lose there Efficiency after 0.2A or .200mA and I know they don’t work over 1.5A, therefore 3.1A / 0.2A = 15.5 LM317. so 16 LM317 are needed to make this run as efficiently as possible.

16 LM317’s Will run in Parallel so that Amps are shared between them all hence the reason for 16 LM317’S. This would now equal 1.25V / 0.2A = 6.3A

C)

So now that’s all done and I hope you understand and follow with me. How do I select the portable Power supply!?

Remember I have a Voltage of 34V and 4.25V across each LD a 34V battery would be big and Amps also very high.

Do I need a Voltage regulator also?

I’m all very confused and really hope you guys can help me here.

Thanks,

• Whatever you do, I'd exercise extreme caution. Honestly, you're playing with over $34V*3.1A = 105.4$ watts of power with seemingly very little electronics knowledge, understanding or engineering experience. Furthermore, lasers (especially at 100W) shouldn't be taken lightly - for reference, a 200*mW* laser is enough to blind you. One mistake and it might cost you your eyesight, burn off a nice layer of skin or start a fire and burn down your house. – tangrs Dec 2 '16 at 18:13
• That being said, if you still insist on doing this, I'd look into switching power supplies for that amount of power. Linear regulators like the LM317 will waste significant amounts of heat which you will have to deal with. You'll also need to find a battery that can safely discharge 100W of power continuously if you would like it to be portable. – tangrs Dec 2 '16 at 18:13
• Yeah, 40W is the kind of level where even reflections can blind you, and I'd start worrying about whether it can go straight through your laser safety goggles.. – pjc50 Dec 2 '16 at 18:30
• 40W ?! If not extremely low efficiency, either the safety goggles are more or less transparent, or will very soon have a hole burned into them that allows light to pass through – Marcus Müller Dec 2 '16 at 18:31
• @MarcusMüller 36W optical power! – user110971 Dec 2 '16 at 19:12

Not an answer, but I felt the need to say this, as it appears you are coming from a hobbyist background, and lack the appropriate facilities to operate the device safely.

What you are trying to do is extremely dangerous. I found the data sheet here. If you go to page 7, you would notice that this laser is a Class 4 of the IEC60825-1 specification. This means that indirect viewing i.e. a reflection from a wall can blind you.

You even get a warning in the data sheet:

Laser Light can damage the human eyes and skin. Do not expose the eye or skin to laser light directly. This Laser product has an optical lens and emits a collimated laser beam. The light from this product, both direct and reflected, is very harmful as it can propagate a long distance while maintaining high optical density. When handling the product, wear appropriate safety glasses to protect eyes from laser light including reflected and stray light. The reflected and stray light spilling into an unintended area should be attenuated and/or absorbed.

Take a look at this chart: You can see that a 2W blue laser can cause eye damage within 200 meters. You are trying to produce 18 times that much power. Your laser will be able to cause eye damage to people that are 895 meters away.

I would suggest that you take a few steps back and think what you are doing. Such high power lasers require an appropriate amount of respect for the damage they can cause, if not handled appropriately. Referring to them as:

...and need to know how to get this boy working!

Suggests that you do not have that respect for the laser. This is dangerous equipment, and not a toy.

• @tuskiomi and you have 8 of them. Still class 4. – user110971 Dec 8 '16 at 20:21