Now Completed Optically Corrected P73 HH Design

Build Pics #4

More progress with the " Dragon's Head "

The attached pics show the set-up for my Optical Test Bed. The LD+mount and the correction optics are shown and adjusted for optimal beam shaping. The components are now ready to be transferred over to the unit Aluminum Main Body. The black semi-circle on the front end is being used as a spatial filter to clip some very slight wings over and under the beam farfield spot. The final build will use the front end cap to accomplish this function.

I decided to go back to Acrylic for the Cylinderical Lens Holder. This is just a matter of looks. Lenses are now epoxied in to place.
The final holder design has a channel for the Plano Concave lens and a Slot for the Plano Convex. I also increased the holder thickness from .25" to .50" to better support the lenses.

See the attached pics. The beam is 11.04mm wide at 25' ( 7.62M). Much better than an uncorrected beam...which is about 125mm @ 25' !!!. At this distance the beam spot is about 9.5mm tall.

At 1250mA the output is 926mW. Just could not clear the 1W bar !!!
Sorry no better beam shots !!! I have just not mastered this talent yet !!!

In the home stretch now !!! Time to lathe some more 2" Aluminum stock to make the end caps from.

CDBEAM=======>

Re: Optically Corrected P73 HH Design -1W and NO LINE

Frickin sweet as always. Why didnt you use an anamporhpic prism set for this? Just testing other methods?

Re: Optically Corrected P73 HH Design -1W and NO LINE

crazyspaz said:

Frickin sweet as always. Why didnt you use an anamporhpic prism set for this? Just testing other methods?

Click to expand...

Anamorphics were trialed when this diode first came out...they just do not have enough power to magnify the slow axis....without using a VERY severe incidence angle as the beam enters the prism !!!

AND....when you do this....the optical losses approach about 25% IIRC.... SOooo...unless you FAC or some fibre optic solution...Both being very expensive !!!!! Cylinderical Lenses are the only reasonable option....that I know of !!! :tinfoil::tinfoil::tinfoil::tinfoil:

Thanx !!

CDBEAM=======>

Re: Optically Corrected P73 HH Design -1W and NO LINE

Nice update! Looking good! I may be wrong but is that lil' snauzer sitting on the couch observing the beam Terrawatt? Somewhere over the years I think you said that.

Re: Optically Corrected P73 HH Design -1W and NO LINE

LaserCo said:

Nice update! Looking good! I may be wrong but is that lil' snauzer sitting on the couch observing the beam Terrawatt? Somewhere over the years I think you said that.

Click to expand...

That IS Terrawatt....She is a Wire Haired Fox Terrier ( Terror)...If allowed...she WILL bite at a laser beam in the air !!!!! She is NOT allowed...ever !!! Dogs eyes are precious too !!!!

She has supervised many, many builds and experiments !!! She has even seen a high powered blue smoke a Milk Bone....I do not think she gave a Rat's Ass....and was NOT amused ....she just wanted to eat it...smoked or not.

It IS a dog's life !!!! SOoooo...Hot Diggity applies !!!

CDBEAM=======>:eg::eg:

Re: Optically Corrected P73 HH Design -1W and NO LINE

+2.5 for a very cute, very professional laser dog.

Build Pics #5

A few more Farfield shots at 25 feet ( 7.62M). As you can see....The beam is now under control....with just a whisper of tails above and below the spot.

At 25 feet with no Cylindericals = a line @ 125mm wide x 9.5mm tall

At 25 feet with Cylindericals = a rectangle @ 11mm wide by 9.5mm tall

Using the Buildlog.net Divergence Calculator...the divergence works out to 1.188 mRad.

See http://buildlog.net/cnc_laser/laser_calcs.htm

That divergence is very respectable for any laser diode. :wave::wave::wave:

Stay tuned !!... This build is coming together...despite Liouville's Theorem...JK !!!..AND

Perhaps....just maybe... the new Oclaro (Opnext) Red laser diode with 700mW at 638nm - HL63193MG ..... may need a pair of glasses /OO\ !!!!!

The Dragon's Head could fill the bill !!! If these Cylinderical Optics can tame the P73 ( Mr Magoo ) Diode....they will benefit ANY Multi-Array LD !!

CDBEAM=======>

Re: Optically Corrected P73 HH Design -1W and NO LINE

CDBEAM777 said:

unless you FAC or some fibre optic solution...Both being very expensive !!!!!

Click to expand...

Is this more complicated than I am imagining? I would guess that as long as you keep the convergence angle smaller than the cone of acceptance of your particular fiber, you just focus it down as small as you can onto one end of the fiber and then use a typical aspheric to image the other end of the fiber, this should result in a uniform, albeit non-gaussian and I would guess unpolarized, beam. Some fiber is cheap, too, just hard to find in sub-centimeter lengths pre-cut and polished.

Maybe it is the multimode vs singlemode fiber that is the important part of keeping the laser light output "laserish" instead of just intense and monochromatic.

I has no LPM, but I do have a few bits of network fiber, ~65-85um. Perhaps someone else could test and see what kind of losses we'd get with a large emission area diode.

Anyways, always fun to see a frankenbeasthulkmonster being built

Re: Optically Corrected P73 HH Design -1W and NO LINE

BShanahan14rulz said:

Is this more complicated than I am imagining? I would guess that as long as you keep the convergence angle smaller than the cone of acceptance of your particular fiber, you just focus it down as small as you can onto one end of the fiber and then use a typical aspheric to image the other end of the fiber, this should result in a uniform, albeit non-gaussian and I would guess unpolarized, beam. Some fiber is cheap, too, just hard to find in sub-centimeter lengths pre-cut and polished.

Maybe it is the multimode vs singlemode fiber that is the important part of keeping the laser light output "laserish" instead of just intense and monochromatic.

I has no LPM, but I do have a few bits of network fiber, ~65-85um. Perhaps someone else could test and see what kind of losses we'd get with a large emission area diode.

Anyways, always fun to see a frankenbeasthulkmonster being built

Click to expand...

Yikes...All I know is that the alignment for fibre optics is very, very critical...and takes a special, very precise optical cage to align the beam in the axial orientation and the X/Y translation to the fibre optic termination plane....SOooo....READ....NOT CHEAP !!!! IIRC..this precise alignment is driven by the need to keep the optical fibre diameter very, very small.

So...yes...Coherent light transmission thru a fibre optic cable is done all the time for industrial/research application....but NOT a " Hobby Budget " deal !!!

Anyone with knowledge of coherent light transmission thru fibre optic ....jump right in here !!! I know enough to be dangerous !!! = almost nothing !!...other than I know it is cost prohibitive and very mechanically demanding !!!

CDBEAM=======>

Thanx and enjoy the rest of the Dragon's Head build !!:beer:

Re: Optically Corrected P73 HH Design -1W and NO LINE

Awesome that is some great work and very detailed. Thanks for doing the hard work for the rest of us.:beer:

Re: Optically Corrected P73 HH Design -1W and NO LINE

So it would seem that the cost has mostly to do with the extreme precision required to focus the laser smack dab in the center of that fiber. 65-85um is very big, in the grand scheme of things, and I would reckon, would have much worse divergence with the same lens. I didn't think of that. So, benefit would be if you could use single-mode fiber of very small diameter, but drawback is that the smaller the diameter, the harder it is to inject laser into fiber.

Re: Optically Corrected P73 HH Design -1W and NO LINE

BShanahan14rulz said:

So it would seem that the cost has mostly to do with the extreme precision required to focus the laser smack dab in the center of that fiber. 65-85um is very big, in the grand scheme of things, and I would reckon, would have much worse divergence with the same lens. I didn't think of that. So, benefit would be if you could use single-mode fiber of very small diameter, but drawback is that the smaller the diameter, the harder it is to inject laser into fiber.

Click to expand...

A big YES...IIRC....not easy to do !!! A single mode fibre with 2um is what would be needed to minimize the divergence !!!!! Double Yikes !!!
MMmmmmm...the thickness of my wallet after tinkering in this hobby !!!

AND...Thanx Jordan !!!!!!....YOU opened the Door !!!!

I will now launch into a prediction from " Beams Crystal Ball"

Our hobby is evolving...as technology drives it forward. We not only have much more power....but the options for corrective optics and multi-diode units are being imagined....and built.

I also see our power demands increasing greatly.....and we will ride on the coat tails of battery development driven by the electric car market.

I predict we will see more and more of these designs presented....right here at LPF. It is just the next logical predicted evolution....in my opinion !! I might be wrong ?????? Nah !!! Time will tell !!!

That's my predictioin !!:thinking::thinking::thinking:

CDBEAM=======>

Re: Optically Corrected P73 HH Design -1W and NO LINE

That's "Hot Diggity, Dog Diggity, Boom what you do to me"
Old song and nice project.
HMike

Re: Optically Corrected P73 HH Design -1W and NO LINE

Hemlock_Mike said:

That's "Hot Diggity, Dog Diggity, Boom what you do to me"
Old song and nice project.
HMike

Click to expand...

Thanx H-Mike !!! Wow... " Your Bench is Deep" to recall those lyrics...Perry Como 1956.....And he is STILL kickin !!! Yikes x 10 !!! Me thinks you are ....." Wise " ....like me !!!! haha

CDBEAM=======>

Re: Optically Corrected P73 HH Design -1W and NO LINE

Now try to get that song out of your mind !!!
Get back on that milling machine -----
HMike

Re: Optically Corrected P73 HH Design -1W and NO LINE

MMmmm......Thanx a lot.......Stupid song !!!

In retaliation for that "gift"....I submit to you the attached picture ...which is an " Artistic Rendering" of the Ego of CDBEAM !!! Ha !!! Get that pic outa your mind !!! :crackup::crackup::crackup:

AND....Machining on Valentine's Day would result in a very bad day...for I am well practiced in stepping ina a big'ole pile a shit in that arena.

CDBEAM=======>