The Green Gargoyle 10.08 W @ 520nm

[RedCowboy]

I watched the Monty Python clip, classic stuff, also like Mel Brooks and have you seen The IT Crowd ? Check it out on Netflix

 

[CDBEAM777]

IT.....WOW.....My daughter is in IT......Funny stuff this clip !....British Humor....always a hoot !!! Sometimes.....er…..most times....what I find funny....well....let us just say...."at the end of the Bell Curve"....Who cares...So it goes.....Bug off !!!!

This render of the GG....may be affordable !! Lasertack components are not the cheapie bits....but they are top notch quality !!!

Chris, I too am a very demanding person in regards to divergence !! Tight'n'Bright….is the way to go

Just a guess as I have not yet made measurements......1.2 mRad...…...Combined Hexagonal beam combination...approx. 5mm

CDB

 

[paul1598419]

I spent too much time watching Monty Python's Flying Circus in my early college days. It is an acquired taste as my wife didn't care for it at all. The Movies were all great to, IMHO.

 

[Alaskan]

Quote Supercar CDBeamer777

"Just a guess as I have not yet made measurements......1.2 mRad...…...Combined Hexagonal beam combination...approx. 5mm"

I'm confused, a 5 mm combined hexagonal beam combination? What? 5 mm? How? The beams themselves are filling up the 6.3 mm diameter lens when at a 8 mm FL, aren't they? Or, is the threaded lens mount masking it down to 5 mm? I still don't understand what you mean by combined though.

1.2 mRad is very good, 1.5 a bit high for me. My thoughts are 1.2 mRad could only be possible with that beam diameter if the beam from the NDG7475 laser diode is so wide it completely fills the 8 mm lens diameter, perhaps with a slight amount of beam truncating. From what I am seeing, the way the box reflection from this diode is eliminated, it makes sense that is what is happening, that the limit of the tube size (and lens inside, of course) is masking that artifact, that the 8 mm focal length causes the output beam to either be right up against the tube size, or slightly larger with some of the beam being cut-off when using this diode with the typical 46 degrees (one side) of raw uncollimated divergence.

​

Without having made the measurements myself, this is all speculation, but I am wondering if I could be correct about this. If so, a 10 mm diameter lens would be a better fit, but even if I had some lenses that diameter, we don't have threaded lens mounts/holders let alone DTR modules for that size of lens tube.

That said, the masking effect isn't a bad thing for some of these diodes, maybe when considering that aspect the G8 is the perfect choice? You have a lot more expertise in this area than I do, I am grasshopper seeking guidance but this is how I see it master.

EDIT: I'm so anxious waiting for your reply regarding this design and what the divergence will really be as well as clarification on how close the beams will be, I'm checking several times a day! CDBEAM, CDBEAM, CDBEAM

​

 

[ArcticDude]

image not found ^_^

 

[steve001]

I'm confused, a 5 mm combined hexagonal beam combination? What? 5 mm? How? The beams themselves are filling up the 6.3 mm diameter lens when at a 8 mm FL, aren't they? Or, is the threaded lens mount masking it down to 5 mm? I still don't understand what you mean by combined though.

1.2 mRad is very good, 1.5 a bit high for me. My thoughts are 1.2 mRad could only be possible with that beam diameter if the beam from the NDG7475 laser diode is so wide it completely fills the 8 mm lens diameter, perhaps with a slight amount of beam truncating. From what I am seeing, the way the box reflection from this diode is eliminated, it makes sense that is what is happening, that the limit of the tube size (and lens inside, of course) is masking that artifact, that the 8 mm focal length causes the output beam to either be right up against the tube size, or slightly larger with some of the beam being cut-off when using this diode with the typical 46 degrees (one side) of raw uncollimated divergence.

​

Without having made the measurements myself, this is all speculation, but I am wondering if I could be correct about this. If so, a 10 mm diameter lens would be a better fit, but even if I had some lenses that diameter, we don't have threaded lens mounts/holders let alone DTR modules for that size of lens tube.

That said, the masking effect isn't a bad thing for some of these diodes, maybe when considering that aspect the G8 is the perfect choice? You have a lot more expertise in this area than I do, I am grasshopper seeking guidance but this is how I see it master.

EDIT: I'm so anxious waiting for your reply regarding this design and what the divergence will really be as well as clarification on how close the beams will be, I'm checking several times a day! CDBEAM, CDBEAM, CDBEAM

​

Just an observation. Applicable to quality made lenses. It seems 12mm diameter lenses is one sweet spot for price. The other is 6mm diameter and I think 9mm. Diameters below and above that start going in price.

 

[Alaskan]

I'd be happier with a 12 mm aspherical or PCX lens over a 6 or 9 mm but that size is considered a fat beam, some of us care more about seeing a tiny thin high brilliance beam close in more than a low divergence beam.

 

[steve001]

I'd be happier with a 12 mm aspherical or PCX lens over a 6 or 9 mm but that size is considered a fat beam, some of us care more about seeing a tiny thin high brilliance beam close in more than a low divergence beam.

That reply was directed specifically to you. We both prize a low divergence beam that looks thin over great distance over a thin beam at close range. Esco Optics has plano-convex acylindrical optics for $60.

 

[Alaskan]

I found ten one inch Thorlabs aspherical lenses with a visible spectrum AR coating on them a few days ago for cheap on ebay

I wish I could find some big aspheric lenses larger than two inch diameter for use in a beam expander, but best I can find, larger high quality ones suitable for lasers are not common, too expensive. I've never seen a high quality AR coated laser aspherical lens larger than two inches, at least, not three inches and larger yet. From what I've found, for lasers, for less beam distortion the choice of lens type fall in this order:

1. Plano-Aspherical (best)
2. Plano-Convex
3. Bi-Convex.

"Since aspheric lenses do not introduce spherical aberration, they are commonly chosen when the collimated laser beam is to be between one and five millimeters." Source: https://www.thorlabs.com/tutorials.cfm?tabID=F7ED0DD5-3F31-4F84-9843-E0F7AC33F413

Re: Your mention of acylindrical lenses. They are the cylindrical counterpart to an aspheric lens, I have not used those for anything yet, but I have plenty of cylindrical lenses in my collection of goodies which are good for making lines, or, even to check to make sure a beam is fully collimated. From what I've found if a beam is fully collimated, the line made by a cylindrical lens is sharpest or thinnest at distance. Can anyone in the forum confirm that finding for me?

 

[Light superglue]

If there could be a GB for Acylindrical lenses, we might only need one pair to correct a knife-edged beam horizontally composed from more than 2 individual beams.

When I tried with Cylindrical lenses the outer beams pair (1,4) focused closer than the inner pair (2,3) due to aberration.



But look how Acylindrical lenses are expensive at Thorlabs! And not very common.

 

[Alaskan]

LS, your work is very interesting to me, I've been wanting to try some of those arrangements for years now, but haven't buckled down to do so. Would be great to have more beams closely grouped without problems. I didn't even look at the acylindrical lens prices there, didn't think I'd ever consider using one, now you have me wondering.

 

[steve001]

I found ten one inch Thorlabs aspherical lenses with a visible spectrum AR coating on them a few days ago for cheap on ebay

I wish I could find some big aspheric lenses larger than two inch diameter for use in a beam expander, but best I can find, larger high quality ones suitable for lasers are not common, too expensive. I've never seen a high quality AR coated laser aspherical lens larger than two inches, at least, not three inches and larger yet. From what I've found, for lasers, for less beam distortion the choice of lens type fall in this order:

1. Plano-Aspherical (best)
2. Plano-Convex
3. Bi-Convex.

"Since aspheric lenses do not introduce spherical aberration, they are commonly chosen when the collimated laser beam is to be between one and five millimeters." Source: https://www.thorlabs.com/tutorials.cfm?tabID=F7ED0DD5-3F31-4F84-9843-E0F7AC33F413

Re: Your mention of acylindrical lenses. They are the cylindrical counterpart to an aspheric lens, I have not used those for anything yet, but I have plenty of cylindrical lenses in my collection of goodies which are good for making lines, or, even to check to make sure a beam is fully collimated. From what I've found if a beam is fully collimated, the line made by a cylindrical lens is sharpest or thinnest at distance. Can anyone in the forum confirm that finding for me?

Those type lenses are round rather than rectangular. Here's a photo for reference for those that are not familiar. What I like about this form is that it better fits tubular form of most handheld lasers.

I'm not certain but I think "Best Form" lenses are also very good. These type lenses have two unequally curved faces.

 

[Alaskan]

That's a nice option for a cylinder pair, if you can find the correct negative FL one to go behind it.

 

[logsquared]

For reference. 8mm Fl lens gives 1.75- 1.8mRad on the green 1Watters.

 

[CDBEAM777]

I'm working on it now !! Crazy day !!! Getting ready for Big Sales Meeting....Must make sure all my facts (fabrications) are in alignment....Perfect Alignment !!! OK....!Beam geometry at the near field ( 50mm from G8 to combining axis. ) =5mm wide x 2mm thick....more in a few minutes !!

OK....At 40 feet ( 12.2M ) the beam measures 19mm x 10mm....SO....Per the 137 Tool....this equates to a divergence of 1.1482mRad....Looks OK....But...I still might add six (6) sets of C-Lenses....to hammer the beam to a more rectangular geometry !!! Dunno

Now....as to what geometry we might be able to obtain with the six (6) beams....arranged in a end-to-end Hexagonal pattern....Hold On....gotta CAD it up !!

 

[Alaskan]

Thank you Bob and logsquared for your data but how do you determine if you are at infinity focus, instead of a long converging focus to a spot, or out of infinity focus where the beam is spreading faster than it would be at infinity?