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FrozenGate by Avery

new lens

kcorbhv

kcorbhv

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i broke the lens on my green 95mw viper and i put an old lens off my rifle scope which i wrecked years ago ,now the beam is so much thinner its great. from a distance of 75 meters the dot is now id say easily 5 times smaller on target and the beam seems to hit objects further away than the original.

viperwithriflescopelens.jpg
 
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i tryed to take some video but it comes out too dark i spent 30 mins looking thru the manual its a panasonic LUMIX DMC-TZ15 .
 
I have a cheap scope that came with a pellet gun, did you use the whole scope or just part of it? Which part, if you only used part of it?
 
kcorbhv said:
i broke the lens on my green 95mw viper and i put an old lens off my rifle scope which i wrecked years ago ,now the beam is so much thinner its great. from a distance of 75 meters the dot is now id say easily 5 times smaller on target and the beam seems to hit objects further away than the original.



Now go and spend a little money and buy a * Plano-convex VIS 0 AR coated lens of the same focal length or close to it. The reason being is you are losing light output because that lens is not AR coated or is broadband coated. BTW what you've discovered by accident is you've made a higher power beam expander. What is the size of the beam at 33 feet = [10 meters] ?

* TECHSPEC® VIS 0° Coated Plano-Concave (PCV) Lenses - Edmund Optics
Click to expand...
 
BShanahan14rulz said:
I have a cheap scope that came with a pellet gun, did you use the whole scope or just part of it? Which part, if you only used part of it?
Click to expand...

it unscrewed out of one end of the scope after i pulled it apart,its approx 2cm in length and diameter
 
This is, basically, the same principle of how a beam expander works.

A beam expander first expand the beam to a more large diameter, then re-focus it with a bigger lens, for have a better divergence.

When you broke the front lens of your module, you remained with the beam passing through the first element, that is a negative lens, that expand it ..... then, focusing it with the larger lens, more distant from the expander than the original one, you got virtually a "built-in" expander ;)
 
HIMNL9 said:
This is, basically, the same principle of how a beam expander works.

A beam expander first expand the beam to a more large diameter, then re-focus it with a bigger lens, for have a better divergence.

When you broke the front lens of your module, you remained with the beam passing through the first element, that is a negative lens, that expand it ..... then, focusing it with the larger lens, more distant from the expander than the original one, you got virtually a "built-in" expander ;)
Click to expand...

yes ,when the laser was stock the beam started thin and went wider ,now it starts fatter and becomes thinner over 2 meters its divergance was 1mm

at2metersbeamis1mm.jpg
 
kcorbhv said:
i measured the beam at 4 meters it was 1.5mm
Click to expand...
You really need to measure the beam diameter at at least 33 feet [10 meters]. I would measure the beam at 10 meters 15 and 20 meters. There's a reason for doing so. I'll explain why if you like to know.

kcorbhv said:
yes ,when the laser was stock the beam started thin and went wider ,now it starts fatter and becomes thinner over 2 meters its divergance was 1mm
Click to expand...
If the beam is really becoming thinner with distance then what is occurring is the beam is focused to about 2 meters [ 6 feet ]. The beam is not collimated for lowest divergence.
Have you measured the beam as it exits the lens and at 2 meters ?
 
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