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Expansion ratio of ebay cylindrical lens set

Feb 12, 2016
Anyone know where to get very small CYL lens 6~10mm, only the convex part but with 50mm+ FL?
I just realized the concave part is not necessary If I am not looking for an infinite beam.

No, I would say you are wrong. The laws of optics (divergence) cannot be ignored in this way. Even for focusing at 200mm an expanded beam would give smaller spot and more power density then raw beam from 31T or 08 sock lens.

2 years ago I have experimented with 08 block and I am sure that the spot of 1-2mm in diameter at 200mm I could get by focusing the 8 expanded beams (post 9) was much tighter than anyone could get from just focusing a 20-pack of raw beams from 31T. Even if 31T emits 2-3x more watts in total.

But that set up demanded some of CNC work and not cheap LSG lenses, not just one focusing lens and that´s it...
However, now I know how I could make it much cheaper with just 4 pairs of CDBEAM GB2 big cylindricals... If we receive them at the end.

Feb 25, 2010
Well.....LSG...I have Not been informed that our supplier will not ship on time for the GB . We are on a count down...19 days till shipment... We will see !!!

OK....On the topic of C-Lens mounting and Lens to Lens positioning...see attached pic. This design was dreamed up by Minomoto / Richard... And machined by me ....SO... FYI...the name: "RBT"....represents- " Richard Bob Trombone " HAHAHAHA

The Plano Convex lens is movable via the slider/trombone section. The Trombone is locked down to the main Ally platform via the single clamping bolt. Thus... the Lens to lens distance can be set and fixed. The Plano Concave lens can be positioned left to right...and Epoxy secured along the rear lower shelf. This Lateral position is fixed only once via the Epoxy. Great Idea Richard !! One way to do it ! There are many ways !!

With adjustabillity comes optimal correction....BUT...then....as I have lamented.... also comes the possibility of becoming " Out of Adjustment ".....Ya just cannot have it ALL !!!



  • RBT-CLM V18 with lenses.jpg
    RBT-CLM V18 with lenses.jpg
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