The Green Gargoyle 10.08 W @ 520nm

[CDBEAM777]

Well...well...I just HAD to start the journey....to an eight (8) x NDG 7475 combiner...See the attached drawing....which shows 1/2 of the LD array....4 x NDG7475's

This is the standard Knife edge arrangement...but the four beams would be EACH Cylindrically corrected....and then the group of four would be propagated thru a set of Telescope optics to reduce the overall combined beam footprint.

Now....we would need two (2) of these Quad units...to be PBS combined....so...2 x 4 = 8 @ NDG7475. This is all speculation of course !! It is too big for the normal cylindrical HH configuration !! Each Quad unit approx. 5" x 6" x 1.75" ….shapes stacked up and down...so 5" x 6" x 3.5" . I do not think we could get it down much smaller !!

Will it ever be built ????? MMMMM...Maybe...Could be..... Maybe I do a Kick Start ???? Maybe I sell a Kidney !!!!! This build CAN be done !!

Thanx a lot....Alaskan and Thanhtung !!! YOU lite the fuse !!

CDB

Note...YES...we will have optics losses...SWAG 10%...so..….but...maybe we goose the 7475 up to 1.4W each......so.....8 x 1.4 = 11.2 Raw Optical Power....11.2 x .90 =10.08 W....out the front door. OH...NO Beam Expander !!! The geometry is not really there for it....but then....we are hammering the beams enough....that a BE might not be needed !!!

 

[RedCowboy]

Awesome, love to see it completed.

 

[CDBEAM777]

Awesome, love to see it completed.

MMM ??? Whada ya say'in ??? Is there any doubt about completion....HAHAHAHA...????????

Completion....WHEN is the big question ????

The biggest hurdle is not the technical challenge...although alignment will be a real hoot !.....The biggie issue is cost of the components !!... Just parts @ $ 2700 USD Would use all Lasertrac mounts, mirrors. /
DTR LD's, Colli Lens and drivers. Hmmm...Man Hours to build..... SWAG @ 60 hr....HMMMM...Out the front door....Meanwhile....$ 4200.....IF the Manhours to build are somewhat correct !!!!!!

Line forms here to commission a build !!! HAHAHAHAHA.....and HAHAHAHAHA

CDB

Note....MAY be able to rotate the Cylindrical lenses 90 degree…..then use one pair of Cylindrical Optics per Quad unit ???? Reduce cost and size???
Must think on this !!! This design may work ??? Comments from the many great builders out there ????? ( A serious request )….I must keep up !!!

 

[BowtieGuy]

Awesome, love to see it completed.

I second that thought; most definitely!

Good luck with this monster, CDB!
This bad boy surely falls into the "go big or go home" catagory, looking forward to following your build progress.

 

[CDBEAM777]

Meanwhile....Thanx all for the encouragement !!! Anyone wanna buy a Kidney ??
Jordi/LightSuperglue/Lifetime/Alaskan/Thanhtung/DTR/Cyparagon/Paul/Bowtieguy/Redcowboy....anyone....anyone....Thoughts on optics/stacking....going to One set Cylindricals per Quad unit ??????
CDB

 

[Alaskan]

Why not use two of these:

Micro Knife Edging / Beam Combiner Module

for an uncomplicated combining of up to four laser diodes

lasertack.com

Maybe because:

Trying to understand this arrangement, I believe the reason might be we cannot use a single cylinder pair for the output of the four beams, as they would not be on center into the corrective optics.... Yikes, this will be a beast to do it right. Maybe better to build one without individual beam correction for each beam? That said, those diodes need lower divergence, it is just too high without at least 3X expansion.



I've seen people use a lens on the output of four knife edged beams to be able to focus them tight or back out again, but not a beam expander, I am sure, because again, the beams would not be on center with the output. What can be done? I want to build something different, perhaps the Gatling gun arrangement I mentioned in PM with individual long focal length larger diameter collimation lenses and throw out trying to square up the beams? I have an idea I'm tossing around my head from left to right to use PCX lenses which have been cut flat on the ends to join up together in a ring as one solid piece of glass to reduce the space between beams on the output. The diodes placed behind them in a ring arrangement.

I like what you are planning here for purity, but it just so damn big. I can't believe I just wrote that as I am having l large pointer built now with a inside dimension 300 x 120 mm optics cavity (350 X 140 OD).

 

[logsquared]

Looks like a interesting project!

I think it could be made fairly compact. However, I'm thinking to do it would require abandoning the pre-made mounts and holders. New diode mounts and mirror adjusters would have to be imagined and built. Precise machining would be needed.

Not a easy project indeed.

If it were me I would probably use 2mm colimators and stack IIII with the SA in the vertical. Actually would look more like .... before expansion. The diode placement would have to be staggered so the distance from each diode to the telescope would be exactly equal. Then one set of cylinders could be used to correct the set of 4 diodes, or all 8 if the distances where equal.

Look forward to following your progress!

 

[paul1598419]

Is this going to be a handheld unit, Bob? Seems like a whole lotta heat to get rid of too. I don't see it happening as a handheld, but stranger things have happened. Will be interested if you actually start on this project.

 

[Alaskan]

My handheld, if you can call it that, will have over 8 kilos of aluminum in it, should sink some heat and could handle eight NDG7475 laser diodes. He could build this into something like what I'm having made and have enough duty cycle for what we normally like to do. When building something that massive, you could put a fan on it too.

 

[CDBEAM777]

First...THANX for the replies....

LogSquared...I apologize for not including you....I have incorporated many of your designs in the past ( Stole the Idea....hahaha )…..You....along with the rest of the " Gargoyle Consortium "....have caused me to spend many, many $$$.....and achieve some degree of advancement for our hobby !!
Who else have I forgotten ????? Sorry in advance !! ...OH...Minimoto is in that crazy group !! We all " Stand on the Shoulders of Giants " !!! and I never forget that !!

OK....I must think on ALL this. Surly to eliminate the need to use a separate set's of C-Lenses....is a goal !! If we just rotate 90 degree a single set of C-Lenses....to expand the Slow axis of four (4) beams....Hmmmm...Sounds Too easy....likely there is a flaw in my Optics Logic ??? Dunno ??

As to size.....well....the " GG" will not be a conventional HH unit....Far, far from it !!!! It will be a Hand Held....hmm...Two Hands.
"
Alaskan….I have another idea for the " Circle " design....I will present shortly that may involve a " Axicon Optic".
Also, I meant to type " Lasertack "...and....the Lasertack Quad unit is a real beauty....BUT....I have learned...that discrete LD mounts provide added adjustability....and when dealing with so many alignment demands....as LS noted !!! I also feel that individual mounts are required.

In closing....perhaps such a "GG" arrangement has already been built....and is in a Projector unit....But....where is the fun in that !!And, if it is...I imagine no one is going to hand us the design details !!!

In the coming weeks, I will do some experimenting !!….on a single or double NDG7475 arrangement. All hands on deck please....I need help with the optics !!!

LS...thanks for your ideas.....Make a picture please !
CDB

 

[CDBEAM777]

Hmmmm...Thanx to the post by the Alaskan in the Ebay section...I may have to consider Anamorphic Prism correction...One (1) set of prism's....for each Quad. Now...the NDG7475 has somewhat decent divergence to begin with !! Surly not as bad as our Red diodes !!
SO....couple this with the excellent lens the G8 for collimation.... We MAY be able to beam correct with Anamorphic prism's....as they are not centric demanding !!! MMMM....Could Be ???? Cuts down cost ( Slightly ), Complexity and size....Will experiment. Pass the Pop Corn !! CDB

 

[Alaskan]

What I like about an anamorphic prism pair is the adjustability for different amounts of correction, you guys put together the idea lining up the outputs of several diodes into one:



I had not heard of the Axicon lens before, very interesting, but how do you keep the ring from expanding as the light travels forward?

An In-Depth Look at Axicons

Axicons can be used in a variety of different fields. Find out more about axicons and how to use them in applications at Edmund Optics.

www.edmundoptics.com

 

[CDBEAM777]

Anamorphic Prism....set to the Zoof Angle.....one of three (3) angles … depending on the degree of magnification that is desired....and the associated power loss as a function of the PP angle...As I was thinking...WHY did they choose a set of PP optics....MMMMM ???? Maybe because that really works well with Multiple Knife Edge Stacks ?????.....OK... I will experiment....for I have all the bits.....just throw'em together....and see what pops out !!
NDG7475 + G8 Colli +BBar coated Anamorphic Prism Pair.....Hmmmm ???? We have the Technology....HAHAHAHA

OK now....as to the other project....the Axicon Lens to combine beams.....Has this ever been trialed ???? As to the Ray Trace.... THIS topic is relevant to the Green Gargoyle....for is may be another way to combine the beams !!!!!

See this Thor Lab site...

Axicons, UV Fused Silica

Thorlabs specializes in the building blocks for laser and fiber optic systems. From optomechanical components to telecom test instrumentation, Thorlabs' extensive manufacturing capabilities allow us to ship high quality, well priced components and devices for next-day delivery. Optomechanics...

www.thorlabs.com

OK...I cannot believe it could be as simple as reversing the Ray Path....No way....!!! I am thinking I have some fundamental mis-understanding of the optics here....The " Goes Outta….becomes the Goes Intta ".....Hmmm..." It's like Lasing a stick of Dynamite " HAHAHAHAHA

SO....Eight (8)….or Sixteen (16) NDG7475.....Circled around the single optic....in a radial fashion...…..all propagating into the single optic....on some different incidence angle as referenced to the central optical angle....then....all exiting on the central Optic Axis ????…..or....maybe we need two (2) of the Axicon....set in a Plano to Plano fashion.... ????

Look at the price for ONE Optic....$ 508.00 !!! Yikes....I wonder if I can " Rent to Own " !!!! HAHA.....Whatever !!

OK....We MUST have some REAL Optical Engineer's on the site !!!!! ?????....Not a Hack like me !!! Where R U ???? Please throw in ?? My brain hurtz !!!

CDB

Note...Added Pic....See...It has been done...In " A Galaxy....Far, Far away " HAHAHAHAHA....And....Eight Beams too !!!!

 

[Alaskan]

Awesome optic, I like it, but appears we are stuck with the expanding ring with that one. I was thinking the same thing too, what if you placed two of them and varied the spacing? Naw, can't be that easy to make an adjustable ring size, could it? My intuition says hell no, it would just undo it. I guess I'm still looking at cutting down PCX lenses to fit into a ring shape to simulate a tube of light which would expand to fill in the gaps as well as the center and become a solid beam in the distance due to divergence. That said, I don't want higher than 1.0 milliradians of divergence, using large PCX lenses would take care of that.



These renditions made for me by a LPF member (can't remember who, years ago) are how I envision the diode beam pattern would be aligned to all be parallel, but instead of collimated as in this drawing, just use raw outputs from the diodes very close to the mirrors to allow centering each beam into collimation lenses over them, after the right angle turn, but green, not red. Using larger long focal length lenses, this would allow the beam to more fully expand to fill in the spaces prior to collimation, and due to divergence, at distance completely fill in the gaps further out away from the laser assembly to appear as one solid beam.

I would not use that many diodes, it's far too expensive, maybe 12 each, which is expensive enough and would require a lot of heat sinking.

 

[RedCowboy]

I thought about having machined a cylinder to directly press 7 diodes threaded for our standard M9 lens barrels and using locking sleeves ( inner threaded sleeve ) to lock the lenses in place which will allow for making alignment adjustments via. the lens barrel thread slack, this would allow for making all the spots/bars overlap in the far field.

It's no where near as fancy but should work and make for a super long throw thick intense green beam flashlight, the cylinder could be aluminum or copper and fit into a substantial host to draw heat, duty cycle would depend on the host but would be useable for short durations in any case.



I made one like this a while back to hold 3 x 7875's running @ 2.4a each fit into a 2.5 x 2.5 inch cylinder aluminum head and it would get hot in about 60-90 seconds depending on ambient temp and what you call hot, after 90 seconds it was plenty warm/hot and needed to cool.

 

[Alaskan]

Robert, that sounds good, I'd like both or at least, you build that one, I can build this one. Nice touch to the diode outputs on that one
I want to build the design I have been thinking about for the lower divergence using large diameter lenses and to see how bright the beam might appear in the far distance (at night) when in a circular pattern. I'd need to go out into the desert to use it here though, not in town.