Building Laser Pointers Using the 445nm Laser Diodes

[Things]

Re: Building Laser Pointers Using the 455nm Laser Diodes

While these new diodes seem like a good idea for pointers, they really shouldn't be available to everyone!

Luckily the price is still slightly up there, so not every man and his dog will have one.

What is very good is now you can add >500mW of real blue to your laser projectors for <$100!!!!!

Chuck it in a heatsink, add a flexmod or die4drive and you have a true blue labby

I go away for a week, come back and 445nm diodes are dirt cheap! The world moved 10 years forward in a week

 

[Grix]

If I understand correctly, you cannot use a rkcstr or groove drive, because they only supply about 500mA max, so you cannot make use of the diode's full potential. Plus they heat up a lot more than boost drivers.

 

[Things]

Most linear regulator drivers will be out of the question for these diodes, unless you want to underdrive them.

The TO-220 LM317 is only rated for 1.5A max, and it gets quite hot, forcing 1.5A thru a small pointer drive will destroy it quickly.

 

[blue lasers]

Most linear regulator drivers will be out of the question for these diodes, unless you want to underdrive them.

The TO-220 LM317 is only rated for 1.5A max, and it gets quite hot, forcing 1.5A thru a small pointer drive will destroy it quickly.

so a flexdrive V4 is a good choice?

 

[t580]

I just want everyone to be truly careful. Temptation is a dangerous thing and these diodes are truly dangerous in a handheld. I thing everyone with kids or little brothers need to take extra caution. You hear of kids teens shooting each other everyday on accident with guns. Think for a minute about how cool a blue laser is and how bad they are going to want and show that bad boy off. Please keep it at a safe level.

Tom / Parent / Laser Enthusiast

 

[JellyCrab]

Yeah, Another reason I want it to be a labby, is because out here the power goes off quite often during strong wind, I don't want myself, or my parents to find what looks like an LED flashlight, then turn it on and accidently blind myself/themselves. So there is no doubt it'll be a labby.

 

[LarryDFW]

Re: Building Laser Pointers Using the 455nm Laser Diodes

Hi Larry,

Not bad looking host! I really like it :yh:

Since the 455nm seems to heat up quite a bit, will you have the heat sink available in copper? Or would the aluminium do it?

Also, I don't understand what does a direct drive power system means, could please explain it?

THANKS!

I am also looking at a similar heatsink in copper. Copper is more difficult to machine.

Direct drive means using the resistance of the host to drop the #18650 voltage from 4.35 to 4.15,
since the voltage required is so close.

I am using new technology nickel anode #18650 lithium-ion cells that are capable of 4.35 VDC.

LarryDFW

P.S. A scanning lab mounted laser can be just as dangerous as a hand held.
I've seen plenty of redirected beams from scanning lasers.

 

[jmgallego]

Re: Building Laser Pointers Using the 455nm Laser Diodes

Got it... Thanks Larry

 

[jmgallego]

To my surprise I received my 445nm laser diode and my host yesterday, perfect timing… ready for the weekend. They took about a week, which seemed like an eternity.

The diode I received was from Pat (ElektroFreak) from his Round 3 Group Buy (http://laserpointerforums.com/f65/round-3-sold-out-cheap-445nm-true-blue-5-6mm-diode-group-buy-51347.htm). This is what I received, the diode and its lens:

From Jay (jayrob), I received the 18650 kit with aluminum heatsink (inside the DIY Green host), the 'Hot' option (which includes the Micro BoostDrive pre-mounted) and the AixiZ housing ([http://laserpointerforums.com/f64/fs-18650-build-kit-easy-assembly-blu-ray-red-43857.html).

Jay attached a note to the host indicating the settings, 640mA, which should be about 500mW (according to the graph being compiled by kevinmassey (http://laserpointerforums.com/f65/post-your-ma-mw-51432.html#post710254), and the cable identification.

Here is a shot of the AixiZ disassembled:

This is a close up of the Aixiz lens:

However, for now, I will be using Jay’s original 405-G-1 lens. I will wait to see what will be the best lens module for the 445nm laser (Jay is testing several options http://laserpointerforums.com/f65/445nm-a130-lens-comparisons-51456.html):

This is the host disassembled, notice the nice aluminum sink and the driver already mounted. I completely forgot to add the copper heat sink to the order. I may order it later if I decide to increase the mA’s for higher mW’s:​

And these are the tools that I used to build the laser pointer, in addition, you will need some thermal compound and a vice:

So, let’s start building the laser pointer.​

First, let’s take a close look at the laser diode. The reason is because I could have ruined the diode, even after reading almost all the 445nm posts, I got confused with some previous laser diode diagrams that I have. So I posted the question o why the middle pin was shorter, ElektroFreak replied with this diagram (http://laserpointerforums.com/f65/round-3-sold-out-cheap-445nm-true-blue-5-6mm-diode-group-buy-51347-4.html#post715227) and Jay also PM me a copy.

And here is a close up of the diode showing how the pins actually look:

(Notice that Pat send me the laser diode with the middle pin shorter and slightly bended, this is good idea since it reminds you that pins is not used).​

1. Put a little, very little, amount of thermal compound on the inside of the hole (indentation) of the front piece of the Aixiz laser housing, this is to increase the thermal conductivity from the laser diode to the Aixiz module.

2. Place the laser diode in the hole of the front piece of the Aixiz laser housing; be extra careful not to smear any of the thermal compound on the glass of the laser diode. (Also, make sure that you “ground” yourself before you touch the diode, this way you do not ruin your diode due to an electrostatic discharge.):

2. Although there are several ways to “press-fit” the diode into the Aixiz, I prefer the way someone described here a while back. Place the small hole of the back half of the Aixiz housing on top of the diode. Make sure the pins of the diode are inside and that is properly aligned as in this photo and press it slightly, enough to hold in place:

3. Next, place the three pieces between the jaws of a vise (notice the laser diode in the middle):

4. Slowly and carefully turn the handle of the vise and start pressing the three pieces.​

5. The diode will then be pressed into the hole of the front piece of the Aixiz laser housing:

6. The laser diode in the front piece of the Aixiz laser housing should look like this:

7. The next step is to solder the two wires from the driver (you may want to have a printed copy of the diagram handy and match it with the laser diode pins) (In this picture the middle ring of the host is not in place, this is just to illustrate the wiring and soldering:

8. Next, insert the back half of the Aixiz housing into the heat sink:

9. Using a hex key, also known as an Allen key or Allen wrench, secure the front piece of the Aixiz laser housing in the heat sink. You may want to put a little amount of the thermal on the inside of the heat sink, and only close to the outer edge.

10. Next screw in the lens. Be careful of not going all the way in, this may crush the laser diode.

11. And… Viola! The laser pointer has been assembled:

12. Next is to test it, but first two things you must to: PUT YOU SAFETY GOGGLES ON!! And second put a cap on the laser output!!.

13. Once you done the two things above, make sure that you are not pointing the laser to anyone or to any reflective surface, next remove the cap and press the ON button:

For comparison, I placed my favorite laser, the 6X Dorcy 405nm ~200mW laser pointer, masterfully created by Dave (daguin ). Notice how strong is the 445nm laser pointer, I had to take the photo from the side rather than from the front, the intensity overloaded my camera and it is almost blinding… and that is with the cap on! So BE VERY CAREFUL when you remove the cap and turn the laser on.

NOTE:
Leaving the cap on and turning the laser on could kill your diode. I left the caps on just to show you how intense this laser is. Make sure you always have the cap on, if you actidentaly turn it on, it is better to kill the laser diode than to hurt someone.​

Now a couple of pictures, the 445nm laser is expectacular, notice how strongly it illuminates the living room. There is no smoke added to the room.

On the next one, I turn on a 200mW green laser just to compare them.

Here I am pointing the lasers to a tree little over 300 feet away, it really do not do justice to the splendor of the blue beam and to its intensity.

I took a couple of short videos, I need to edit them before I can post.

On the side note, as I mentioned above, this laser it is set to 640mA, with an estimated output of around 500mW (http://laserpointerforums.com/f65/post-your-ma-mw-51432.html#post710254), that is half the power that this diode is capable of outputting. I made a mistake, I put the Aixiz lens module that came om the package instead of Jay’s original 405-G-1 lens, this is what happened, the plastic melted and created a larger hole:

I had to remove the debris that deposited inside the front piece of the Aixiz housing and on top of the laser diode.

Well, it was really fun and rewarding to build this laser, hope these notes help you when you build your own.​

 

[Xtrm2Rick]

looking verry nice jmgallego, just 1 thing isnt it bad for your diode to put your laser on with the cap on the lens?
i read somewhere that the backflash can kill the diode, im not sure about this i just remember reading it somewhere on LPF.

 

[jmgallego]

Thanks Xtrm2Rick

Yes, it could kill the diode, but in this case, I do not care it gets killed, I am more concern about accidentally turn it on and hurting someone. It can also burn the cap and put debris in lens, like what happened to the Aixiz when I turn it on for the first time.

I realize that this laser does not, and was not meant to, comply with the safety laser standards. It is missing the lock out (or safety pin), an indicator, push button (instead of the clicky button) a delay or beam blocker/shutter. The fluorescent caps is translucent so you know that it is on, some of the energy is diffuse and some is used to make the cap fluoresce. I think as the builts will evolve with this type of monster, and include some of the basic safety requirements.

Thanks for the feedback!

 

[jmgallego]

Re: Building Laser Pointers Using the 455nm Laser Diodes

Figured it could be nice for people to post their plans for others to inspect

Done...

 

[jbtm]

So driving the diode with a FlexDrive at 600mA will be no issue? I wasnt sure if there was a difference between the micro boost and the Flexdrive in performance as to how much power the thing can output, to run the laser safely.

Also, when using the dummy load of 1N4001 diodes and 1 ohm resistor, Is it best to connect it and adjust the power according to red lasers or bluray lasers?

 

[daguin]

bump

Peace,
dave

 

[jmgallego]

So driving the diode with a FlexDrive at 600mA will be no issue? I wasnt sure if there was a difference between the micro boost and the Flexdrive in performance as to how much power the thing can output, to run the laser safely.

Also, when using the dummy load of 1N4001 diodes and 1 ohm resistor, Is it best to connect it and adjust the power according to red lasers or bluray lasers?

I my rush to push my diode to higher currents, I forgot two things:

- The maximum current the microboost allows, 1000mA and
- To test the ACTUAL current on the microboost by using the dummy load.

To get the to current of 1000mA all you have to do is max out (clockwise) the pot on the microboost driver. However, that does not guaranties that is actually 1000mA, to verify the final current you need use the dummy load.

You also use the microboost to to a current that will extend the life of the diode, say <600mA. If you decide to go this way (which a ask you to consider) you can use the FlexDrive since, as you said, has a max of 600mA and go half way, to about 300mA, unless you need more power out of your LD.

Jose
And... always practice safe lasering

 

[Gryphon]

Great build, and very well documentation on the build up, its nice to be able to follow along easily