DIY Green He/Ne Build. Mellow Yellow DPSS Hybrid

[JLSE]

So once again I got an idea.. Looking at an old He/Ne tube, more
specifically, the 100% reflective mirror at the rear.
What if I tried centering a 532nm module through the bore of
the He/Ne?

First thing to consider was loss.. Not a big deal, and to mix with a 1mW
632.8nm, would only take a few mW.

I first tried a 70mW 532 to see its effects on the mirror (if any) and
what kind of loss would be associated to passing the 532nm straight
down the center.

So from 70mW, it dropped down to 35mW.. So the loss is half, but again,
not important.. I could still use a 10mW 532, and 5mW would be more than enough..

I milled out the mount, tested my He/Ne tube, and began the alignment.
To my surprise, the beam passes right through, ignoring the coating of the mirror
which is meant to internally reflect the 632.8nm.

Im still wiring the H/V for the tube. Extra care will be taken in this step
so the 808nm LD in the 532nm module doesn't see any hits of 1,000+ volts DC. :scared:

I am adding a linear control to the 532nm, so in the end I will have a
'kind' of tunable He/Ne, ranging from green to red.. This includes
orange and yellow :san:

So here you have it, a pseudo tunable He/Ne, DIY style :beer:

More pics and a video are in the works pending completion.

 

[Trevor]

Re: A Most Excellent He/Ne Build. Mellow Yellow

Really interesting project; good luck!

Though I will say, it might behoove you to look into a green diode. Pricey, but I think you might be better able to get reliable power out of it at the sub-2mW mark that proper mixing will require. Or have you already eliminated that as a viable option?

Trevor

 

[JLSE]

Re: A Most Excellent He/Ne Build. Mellow Yellow DPSS Hybrid

The advantage to a DPSS module is the beam size... Try to put a diode's
collimated beam down the center bore of the He/Ne would be a task on its
own.. if at all even possible. Tried it with a 445, and the loss was massive.

The module is one of mine, and very stable. Over the course of an hour, it
only drifts a fraction of a mW, but is not entirely important.. Im not aiming
for a specific colour, and to hold at it.. Sight changes would not be too noticeable
and easily fixed by adjusting the brightness of the 532..

 

[ShortyInCanada]

Sounds like a nice frankenlaser project.
Looking forward to the pics and video.
:gj:

 

[JLSE]

Whats interesting about this one, is the mixing.. Both beams are coming
from the same point..

The restriction of size in the bore also does not allow the 532 to exit larger
than the 632. Usually when you use dicros or the like, the 532nm beam is inherently
smaller than that of the red.

The idea with this build is that the 2 beams will exit the same size. You end up
with matching beam diameters, and the spot size can be set so that they
are also equal at a given distance.

I expect the results to be combined beams as perfect as I could possibly get
from combining 2 wavelengths :san:

 

[532 with Envy]

Some neat stuff you have going on there! I love the windows built into the build, looking forward to more photos.
:gj:

 

[JLSE]

Some neat stuff you have going on there! I love the windows built into the build, looking forward to more photos.
:gj:

Being able to see the tube lit either with the original plasma glow
or the green was a must. Its such a low power build that the wow factor
will have to rely on more than just the beam...

I took a bunch of pics and some video of the build process for the host
and will add those to the thread when both lasers are up and running.
Figured i'd edit in as much footage into the video including the final
product..


Im wondering which one of my friends will be the first to stick their finger
into that rear opening :eg:

 

[532 with Envy]

Im wondering which one of my friends will be the first to stick their finger
into that rear opening :eg:

LOL....that's always good for a quick reminder!

Looking forward to the build notes...good luck!

 

[JLSE]

Just putting the kids to bed, then ill be back on the bench.. Looking to get
this buttoned up tonight and add the remaining media..

 

[Gryphon]

To bad green henes dont glow green like your pic

 

[JLSE]

To bad green henes dont glow green like your pic

Well when the tube is lit, I doubt you will see much green in there.
The tube is pretty bright with that pink glow.

On a side note, for those who have a dead tube, you can always strap
a green to it and just pretend :san:

One thing I did neglect to mention, anyone who tries this simply
by placing a 532 pen behind a he/ne tube in operation, be careful
not to get too close..

The H/V will leap right into your hand

Surprisingly it would just hurt, but not kill the 532 laser... dont ask how I know.

 

[n2stuff]

Yes sir HeNe's will bite. Been thier done that many times.

Man I do love your creations You have quite the imagination. Keep them coming.

Well when the tube is lit, I doubt you will see much green in there.
The tube is pretty bright with that pink glow.

On a side note, for those who have a dead tube, you can always strap
a green to it and just pretend :san:

One thing I did neglect to mention, anyone who tries this simply
by placing a 532 pen behind a he/ne tube in operation, be careful
not to get too close..

The H/V will leap right into your hand

Surprisingly it would just hurt, but not kill the 532 laser... dont ask how I know.

 

[JLSE]

Yes sir HeNe's will bite. Been thier done that many times.

Man I do love your creations You have quite the imagination. Keep them coming.

I hate getting zapped.. ive come to be quite good at avoiding
it, but we all have those moments.



An update, the 532nm crapped out. Seems I used the wrong
808, and the current I was running it at was above its safe zone

I have to make another, as any old module will not be on center
and it doesnt pass through. I have left room for minor adjustments
but most modules are too far off, and the beam is too wide..

A couple of pics of the first 532..

 

[AUS]

Interesting !
I have heard of shooting a HeNe down the bore of a CO2 or an NdYAG laser for aiming, but this is something new and quite brilliant

 

[JLSE]

Interesting !
I have heard of shooting a HeNe down the bore of a CO2 or an NdYAG laser for aiming, but this is something new and quite brilliant

I had just assumed that they used optics and cubes or something of the like
for aiming. Though I have had no up close experience with any industrial type
lasers..

The idea hit me when thinking of 2 beams from the same source, and making them
as close of a match as possible.

The idea to pass a beam right down the center of another seems to be the ultimate way
of combining..

This one is more of a mock up... I would really like to try this with a 15mW tube or
stronger if I can get my hands on one.

I wanted to use the Melles 5mW tube I have, but its in the metal housing and do not
want to risk removing it..

 

[lasersbee]

I'm getting a little fed up of this.....

Every time I turn around you have some other do-dad
that impresses the He!! out of me...

Keep up the good work "outside the box"....:gj:

Jerry