New 400mw Handheld Green Laser

[Cyparagon]

Isn't it true that the more powerful the laser the worse the divergence?

Yep, that's the rule of thumb.

 

[Danjoo]

Its because the beam is not emited from one single point i think or? istn it?
I think this is main reason that high power have bad beam specs.

Enlightment please?

Cool build nice Big Heatsink!

I have to agree with the Beamspecs. I run a Aconsen 350mw module @2,8 Amps and it put out alot of power (around 500mw)but differgence is very poor.


Daniel

 

[steve001]

Bad divergence you say. That's an easy thing to solve without making a beam expander.  You'll need to remove the original collimating (C) lens if possible. If you can't do that then you'll need to make a whole new beam expander.
Now, determine the focal length of the original (C) lens ? Do you know how to do that ?
Purchase a AR coated lens with a focal length no less than 10mm more than the original.
Machine an extension tube with threads to attach it to the laser. It should have female threads for the lens mount.  Extend the tube about 2cm beyond the final lens position. Helps keep dirt out.
Machine a male threaded lens mounting ring with an inner recessed lip for the lens to rest in.  With two divots for too insert a point tool for position adjustment.
Essentially what this is doing is extending the length of the optical system.
Can the diverging lens be removed ?
If you end up having to make a beam expander you might want to consider recessing the portion of the expander to accommodate two stacked diverging lenses.  
This will increase the Rayleigh length.  More later
Based upon this modules specifications. If you were to make a beam expander using two lenses with a -6 efl and 30 efl you'd have a beam 5.5mm in diameter with a Rayleigh length of 60.15 feet. What this means is the beam diameter at this distance is 1.4 times the beam diameter at the lens or 7.7 mm in
diameter
Adding a second -6 efl lens you'd achieve a Rayleigh length of 261.068 feet. Beam diameter is 11.458mm at the lens. Beam diameter at this distance is 16.04mm.
About the size of an American penny.
Divergence would be around 0.15 mrd

 

[rog8811]

Some nice machining work there, the whole build looks really good.

I am interested that you anodised it yourself, is it an easy task? what do you need to be able to do it?

Regards rog8811

 

[MarioMaster]

I'm honestly surprised it was able to reach the power output. Seems like they may be worth the cost after all.

 

[billg519]

There are pump diodes used in green lasers that are essentially a 9mm open can diode.  I have a 2w one in my collection.

rog8811
About anodizing -

A clear anodize is not a difficult process. You need decent ventilation, and the sulphuric acid bath has to be treated with respect.

You need :

A car battery charger
A plastic container big enough to hold the item to be anodized plus 50%
Some solid lead plumbers solder wire (I'm using 3mm dia.)
Some aluminum wire
Some battery acid from the auto parts store (sulphuric acid)
Some steam distilled water (gallon jugs at grocery store)
A pot of water for rinsing
A pot of boiling water on the stove
A cleaned, grease/oil free part to be anodized

In your plastic container, put 4 parts distilled water, then slowly, wearing goggles, stir in 1 part battery acid.
This is the anodize bath. Make a negative electrode from the lead wire in a shape that loops around the bottom of the container and runs up the side and over the top. Connect negative clamp of car battery charger to this lead wire. Do not let negative clamp fall into anodize bath. Only the lead wire can be in the bath. Using the aluminum wire (could be al mig wire, but must anneal with lighter or wire snaps) twist wrap your part to be anodized, leaving a length of aluminum wire to attach the positive battery charger clamp to. Lower the part into the anodize bath by the aluminum wire, and connect the positive battery charger clamp. You will see fizzing bubbles form on the lead negative electrode, and also on the part. Let this process go on for 30 - 45 minutes.
Get the pot of water boiling on the stove.
When anodized it will look milky yellowish white. Disconnect battery charger and lift part out of bath with the aluminum wire. Dunk in clean water bath to remove excess acid. Place part in pot of boiling water on the stove. The boiling water must cover the part.
Boil the part for 20 - 30 minutes to set and harden the anodize. Remove part and pat dry with rags, cut off aluminum wire,  allow to cool, buff with rag. Its anodized.

Try to anodize as soon as possible once machining is completed.

Before the part goes in the boiling water, it can be dunked in a dye bath. Sharpie markers (black or color) will write on the part, and be made permanent by the boiling step.

You don't want too much lead wire in the bath, or too much current will be drawn, causing the bath to foam. Less surface area of lead wire than of part being anodized.

Make sure the aluminum wire makes good electrical contact to the part you are anodizing, or you will only anodize this wire. You can do several small parts at once.

Hope the above helps. Try anodizing some scraps to get used to the process, test any colors on scraps first.
You can purchase the real dyes from caswell plating  www.caswellplating.com  if you are in the USA. All sorts of things, even clothing dyes and some inks will work if you want to experiment.

 

[tatman]

2 cents: For color anodizing they have special dyes that mix in the bath. But I have used Rit fabric dye in the bath with acceptable results.