What do you notice about the two schematics you posted? What lenses will Redcowboy be using?
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FrozenGate by Avery
Home Made Monster Beam Expander !
- Thread starter Accutronitis
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What do you notice about the two schematics you posted? What lenses will Redcowboy be using?
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The lenses in the Galilean type beam expander....
I thought a G2 lens is positive. Perhaps I'm mistaken.
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A G2 lens isn't part of the beam expander......
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I think Alaskan and myself played with some math before, as well as the whole thing getting long and wide it's better to correct the aggressive axis 1st, but I was thinking I would play with it a bit, that's what I was saying about the beam crossing over it's self making the device longer, also the spot will be an ever growing line, proportionally that is.
However to get fine adjustments with a slider a longer device with the positive aspheric G2 lens could be used.......it's wrong and I know it, we need to correct the aggressive axis 1st, the train being 44/G2/6Xcly/Galilean BE
Yes that's a list, but the 44 is a dang floodlight, albeit an affordable 8W one.
However to get fine adjustments with a slider a longer device with the positive aspheric G2 lens could be used.......it's wrong and I know it, we need to correct the aggressive axis 1st, the train being 44/G2/6Xcly/Galilean BE
Yes that's a list, but the 44 is a dang floodlight, albeit an affordable 8W one.
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I agree the 44/G2/6Xcly/Galilean BE is the way to go and from a building it point of view it's the way that makes the most sense, It would be very difficult to go something like 44/6Xcly/G2/Galilean BE or something like that IMO.....I think Alaskan and myself played with some math before, as well as the whole thing getting long and wide it's better to correct the aggressive axis 1st, but I was thinking I would play with it a bit, that's what I was saying about the beam crossing over it's self making the device longer, also the spot will be an ever growing line, proportionally that is.
However to get fine adjustments with a slider a longer device with the positive aspheric G2 lens could be used.......it's wrong and I know it, we need to correct the aggressive axis 1st, the train being 44/G2/6Xcly/Galilean BE
Yes that's a list, but the 44 is a dang floodlight, albeit an affordable 8W one.
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Yes, impossible IINM.
I think Alaskan and myself played with some math before, as well as the whole thing getting long and wide it's better to correct the aggressive axis 1st, but I was thinking I would play with it a bit, that's what I was saying about the beam crossing over it's self making the device longer, also the spot will be an ever growing line, proportionally that is.
However to get fine adjustments with a slider a longer device with the positive aspheric G2 lens could be used.......it's wrong and I know it, we need to correct the aggressive axis 1st, the train being 44/G2/6Xcly/Galilean BE
Yes that's a list, but the 44 is a dang floodlight, albeit an affordable 8W one.
I think you can make this setup less complicated. Beam shape first. Then use an expander. I think beam shaping does two things. 1 it shapes the beam obviously. 2 it collimates the beam by controlling the fast and slow axis.
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Beam Shaping the 44 ? Can you explain how this is accomplished without a G2 type of lens or cyl lens correction ? I'm all for making thing simpler and getting the same results !
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I mentioned beam shape first. Beam shaping requires a cylindrical lens or lenses. Cylindrical lens pairs do collimate as I thought. There seems to no advantage to collimating first then shaping the beam.
Cylindrical lens info.
https://www.edmundoptics.com/resources/application-notes/optics/what-are-cylinder-lenses/
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They only collimate on one axis per pair and trying to get them close enough to the raw diode output to catch all the output before it could diverge too wide would be very difficult.....
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Where did you read that? How does a G lens collect all of the light? By being very close. Why can't the cylindrical lens be placed close?
This is what the link states.
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I didn't read it, I experienced it.
A G2's focal length is such that it must be VERY close to the diode which is what you want with a 44, You don't have to screw it out all that far before the rectangular, wide, fan shaped raw output of the 44's diode gets clipped by the G2's barrel, When using a DTR copper module with a 44 installed if you removed the collimating lens the fast axis divergence is so extreme that the module clips both ends of the fast axis "fan" as both ends of the fast axis "fan" strike the threaded part of the module.
The fast axis output of a 44 is so extremely wide that unless you cut off part of the DTR copper module you could never get a cylindrical lens close enough to the diode before part of the fast axis got clipped.....
The G2 catches all the raw output of the 44 before it has a chance to diverge very far and turns that rectangular, wide, fan shaped raw output of the 44 into a fairly tight (relatively speaking) beam that is still rectangular and fan shaped but on a very small scale which gives you a beam that can be worked with to tame the still much wider fast axis.....
The raw output divergence of the 44 is so extreme that if pointed at the ceiling (depending on the height of the ceiling) without a collimating lens it makes a huge rectangular box that is around 2 feet by 8 feet in size !
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I have one thing to say. Engineer it so it works.
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I did and it does, Very well i might add.....
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Yea, to do any better would mean using a FAC lens right in front of the emitter, but I wont remove the can as oxygen breaks down where all that light exits the front mirror and damages it, if oxygen is introduced that is.
The G2 has a rear FL 0f 2.39mm and my print on my concave cyl lens is 1mm wide and 4mm tall, but it is the 1mm wide axis that is the aggressive axis, I think G2 then 6X is the most practical simply because of the extreme divergence. Also the G2 is very efficient and has a very short FL.
The G2 has a rear FL 0f 2.39mm and my print on my concave cyl lens is 1mm wide and 4mm tall, but it is the 1mm wide axis that is the aggressive axis, I think G2 then 6X is the most practical simply because of the extreme divergence. Also the G2 is very efficient and has a very short FL.
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