What is this set of optics used for?

[Devil_Master]

I've been reading about the NUBM44 diode, which is very powerful but has a highly divergent slow axis, and I've been suggested to use this set of lenses to reduce its divergence.

Premise: I've never dabbled into the optics part of lasers, only into the burning part. Well, it's never too late to start, is it?
So, I see that there's a plano-concave cylindrical lens, in front of a plano-convex cylindrical lens. That makes me infer the following:
1) the fast axis of the beam must be aligned to the vertical axis of the lenses, so that the lenses themselves won't interfere
2) the plano-concave lens will expand the slow axis of the beam, while the plano-convex lens will make it rectilinear. This will make it impossible to focus the beam into a point, but it will be useful to project the beam to long distances
3) in order to focus the beam into a point, the plano-concave lens must be removed, so the divergence of the slow axis will actually be reduced

Can anyone with direct experience with those lenses (or similar sets) tell me whether my assumptions are correct?

 

[lasersbee]

There are a few members that have used the
Cylidical Lens Pair...
CDBEAM777 comes to mind....
Perhaps he will chime in or you could contact
him by PM.

Jerry

 

[logsquared]

I've been reading about the NUBM44 diode, which is very powerful but has a highly divergent slow axis, and I've been suggested to use this set of lenses to reduce its divergence.

Premise: I've never dabbled into the optics part of lasers, only into the burning part. Well, it's never too late to start, is it?
So, I see that there's a plano-concave cylindrical lens, in front of a plano-convex cylindrical lens. That makes me infer the following:
1) the fast axis of the beam must be aligned to the vertical axis of the lenses, so that the lenses themselves won't interfere
2) the plano-concave lens will expand the slow axis of the beam, while the plano-convex lens will make it rectilinear. This will make it impossible to focus the beam into a point, but it will be useful to project the beam to long distances
3) in order to focus the beam into a point, the plano-concave lens must be removed, so the divergence of the slow axis will actually be reduced

Can anyone with direct experience with those lenses (or similar sets) tell me whether my assumptions are correct?

you are spot on with the exception of #3. You can still focus to a point with the -lens in place by moving the two lenses further apart.

 

[hakzaw1]

I would like to think that the 'more serious' here only touched briefly on the 'burnin' stuffs' phase.. And more 'others' see this practice does not help our efforts to keep our ' pastime' legal.

I am never surpirzed reading how a demo of burning (to parents mostly) did not get the hoped-for reaction. While nowhere near the damage caused by aircraft lasing.. prolly the worst thing for us.. and it is near impossible to get others to see what 99% of us ACTUALLY do with our lasers. Banning/making illegal(>5 mW) would have zero effect on aircraft lasing. about as dumb as thinking firearm bans would effect the 'bad' guys..which, in all likehood, only gives the sellers of these much more profit .

about OPT Poland's correction optics?- 60 to 75$usd (I assume shipping also to be added) is afaik a good price range for these. I base that on how many go to OPT. and not reading much about sources in places like China or USA..
someone please prove me wrong.


happy lasing
hak
btw the 'hak' on MISSCORD is NOT me..
SOME who are may want to check themselves for fleas...or ticks.

 

[Devil_Master]

RedCowboy too. I've built a pointer using the NUBM44 with a pair of 6x cylinder lenses and when corrected, and followed by a 3x expander which has an adjustable focus, you can focus to a mighty intense burning spot, far more so than without the corrective 6x cylinder pairs.

Are there pictures of the setup?

 

[paul1598419]

I have the OPT 6X lens pair and am waiting to finish another project before I build my cylinder lens corrected NUBM44 build. I have everything necessary to complete it, but after I finish a NDG7475 build in an MS-SSW-II. I know RedCowboy will have photos of these lenses in use. I have seen them myself.

 

[hakzaw1]

___________________________________
That I did NOT know..
sorry now that I hesitated..

about China--TY for mentioning that there are exeptions.. NOT entirely fair to paint ALL w/ the same brush.

I gave Alan (blab1391 on ebah) the chance to do better by us and he has done an outstanding job..He will unlikely please ALL and do that ALL the time but so far.. I could not be more pleased.. he has several optics at auction ending today some very soon and at last look my very low max bids have not yet been passed..
Someone elses loss (side from Alan) is my gain.
I fully expected the X-cube I won for a penny would not even ben sent-- those kinds of auction ending are commonly known for getting lost in transit or some other thing to keep the winner from winning.. Blab sent instant TY and asked for my mailing address--
I was 'AHA' next he will want my SS#-- so my rude and uncalled for reply was-''its in my paypal info and correct' OK .. no reply -hour later I get tracking #- hmmm I felt teeible-but still , in the back of my mind,
I was thinking it would be an empty box the or rock-in- the -box
- -whoa was I wrong on every point.. overpacked small box came way before I expected it.cube -a nice size of 18 mm looks as good as any I have seen-any defect wasnot visible and his listing has....
' Very Slight'.. wth is that??
turns out he added more but was over the limit. he is new to ebay.
not enough room for the rest..'Defects' ( his 2nd ever listing) since he lives there (where, likely all defective cubes listed come from according tto Alan) he can buy in 'person'.
''.
Well proven by how quickly my suggestions became listings -- my 'corrections' were instantly acted on-- typos fixed.( you know the kind-using mw/Mw/MW etc clueless)
I had/have no intention of getting Alan 'under my control' and/or taking advantage and would rather that all here can be a part of getting super deals.. The only thing I Will Do...make an occasional lowball bids.0 . very low-so any LPFer who wants some can easily outbid me..
and any calling dibbs.. I will not even open. but to win -- best snipe is NOT after you have bidded when the bid was small

a snipe service is the best way to go (PM me for more)

but if you want to please me.. mention my name and LPF to Alan at blab1391

-call dibbs here or at the D&D mega thread.. (you are welcome btw) or put it anywhere as a thread and use blab1391 in the thread title. I will let yu all know when Alan joins & his chosen username( he will run that by me BEFORE he chooses LOL) HAD to tell Alan about meanings or negative connotations to 'blab' like Blabber and Blabbermouth.. My suggestion was 'KingKube' fitting as he could be the next go-to guy for Cubes and other optics (for hobby level and then some).. we shall see..


I will give him lots more 'home work' then see if he can satisfy those who demand perfection later sorry-- $60 or $75 for what now? -- let me know what you would like to see & I will (myb) pass that on.
HE offered me help doing a GB.. that's a first. its usually me asking about that
watch for my feeler threads- lots more comming!!

I certainly hope when he joins LPF he will be made to feel at home.. he will be an excellent vendor/member-- never spamming.. and his usual polite manner to only reply to Qs asked. BTW he is sharing the new E store with (AFAIK) his GF--which will explain all the 'other' stuff listed there.. yoga pants -etc.

as said
....some of his stuff listed by any other EEKBay seller is always BIN /make offer NOT an auction.. nearly 100% of some stuff is NEVER sold at auction only BIN or make offer etc. btw snipe is not used for other sales..only auction.


that is how I found Alan== saw that it had no bids ..then 1 cent high bid from me-- my max was $5 iirc. so the one cest bid was determanated by ebay. on X-cube and thought;;;;hmm I sure can out bid that.. and even tho I shared that at LPF no bids of substance in 2nd listing as I won that one for cents.. IT will be here soon- I want to test/ review when I have more than one from Alan so I can compar0e for some degree of consistency. Told him to list the prisms as a pair (2 pcs) even tho he did not get the kind we use for correction he gave it a good try and listed two sizes the next day.. BUT if any are made there (like OPT sells) he will find them.
Even defective optics will work for me-- too broke to buy the best and WHY should I???
we forget sometimes that most here are hobby level.... no QC.. required hahahah