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need a smaller mrad, a better collimation. is there lens that can do this for me? for sell?
need a smaller mrad, a better collimation. is there lens that can do this for me? for sell?
Hi udanis,Well you are looking for precision optics. Anything thing with "precision" in it's name is going to be expensive.
So you want a custom beam expander (well reducer in this case) for less than $80?
Hi udanis,
No he doesn't need a beam reducer, it's a beam expander. The beam expander will expand ie increase the beam diameter, but also reduce divergence by the same X factor.
Hi udanis,Okay beam expander to reduce the diameter of the beam
Hi udanis,
No, a beam expander increases the diameter of the beam, while at the same time reduces the divergence.
Divergence is how much the beam spreads out and it's inversely proportional to the diameter of the beam.
It depends on the application.
For example, lets assume a 1.5mrad beam with 3mm diameter at aperture. At 10 meters the dot/beam will be 15mm in diameter. At 100 meters the dot/beam will be 150mm in diameter.
Now put that same laser through a 10X expander and you will have a 30mm beam at aperture with only 0.15mrad divergence. So at 10 meters the dot/beam will be 31.5mm in diameter. But @ 100 meters the dot/beam will be 45mm in diameter... less than HALF the size of the unmodified laser beam. This means energy density and intensity are MUCH greater at longer distances.
There's a balance point for deciding if a beam expander is helping or hurting your beam charactaristics. In the above example, the distance is 20 meters. At 20 meters, the beams above would project the same dot size. Less than 20 meters and the unmodified beam would project a tighter beam/dot. Greater than 20 meters and the "expanded" beam would project a tighter beam/dot.
The reason most people don't bother with beam expanders is the expense and lack of need to point at "long distances". Most people here are calibrating projectors for certain distances, using laser pointers at room distances, or burning things. How many people here really care about beam profile & dot further than we can accurately perceive it or burning at long distances?
This is an illustratoin of what I'm talking about (regular beam vs 10X expanded beam):
Dragonlasers said:The beam expander can be connected to our Viper, Aurora and Spartan Series lasers using optional adapters.
Hi udanis,
Divergence is how much the beam spreads out and it's inversely proportional to the diameter of the beam.