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Focal length of AixiZ acrylic lens?

IgorT

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Does anyone know what focal length the acrylic AixiZ lenses have?

If i wanted to buy a different lens, that would have to work in the same module, what specs do i have to be looking for?


Thanks!
 





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the focal length is adjustable by screwing the lens in or out....

and you want one that will fit a 12mmX30mm module. that's the standard size.
 

woop

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sk8er4514 said:
the focal length is adjustable by screwing the lens in or out....

and you want one that will fit a 12mmX30mm module. that's the standard size.

the focal length of a solid lens is always fixed.
you are just moving the lens (and its focal point) when you screw the lens in and out.

the focal length of the aixiz acrylic is something around 5mm, or 2.5mm from the base of the black plastic.
its pretty long, that's why the beam is so wide
the coated glass optics i bought from the aixiz site have a similar FP.

i suppose you would want a lens with the shortest FP possible, so you can have the lens closer to the diode and have a thinner beam
 
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and why exactly dont they incorporate glass or even plastic lenses with much smaller focal points? I really dont understand this. A tight beam is exactly what most laser enthusiasts seek, yet they arent available.

Anyone know of a cheap replacement lens that would fit in a aixiz or meredith module that would significantly reduce the beam diameter?

and if not, would anyone be interested in these as much as i would?
 

woop

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I tried using the objective lens out of a cd drive, it has a very short FP and throws a really tight beam.
 
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woop said:
I tried using the objective lens out of a cd drive, it has a very short FP and throws a really tight beam.

and it fit into your Aixiz module? Where did you pull this lens out of (what drive specificily)?
 

tomcat

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well i have a meradith glass lens system for my current laser and a cd objective lens fits in there nicely but the lenses get damaged by the laser and so i have to replace em every now and then or i just use my glass meradith for a good beam also wide beams can be good sometimes because its eisier to get good collimation to infinity with a wide beam lens than with a fine one thats why people use beam expanders for distance the tightest beam i know is from a bluray objective lens becuase that has a very short focal leanth

the objective lens is the one that sits above the cd and focuses the beam onto the cd its usually in a floating cradle with coils on it for the electromagnetic focusing system (some great little magnets here) a dvd RW lens would last pretty much forever but i only have cheap cd readers here to rip apart so the lenses get artifacted and produce scatter after a while
 
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Is it acurate to say that if you use a shorter focal length you will gain more power?

This drawing shows what i think would happen.

fl3.jpg
 
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So an Aixiz lens has a FL of ~5mm?

what is the FL of a typical DVD drive lens?
 

JLSE

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k-shell said:
So an Aixiz lens has a FL of ~5mm?

what is the FL of a typical DVD drive lens?


Not sure of the numbers, but those lenses have to be almost 3x the distance away from the diode to get a decent beam. To get a smaller beam in what I have tried is to find a smaller lens that sits just as close to the diode as the acrylic axiz. The smaller the diameter of the lens translates into a smaller diameter beam. A good start is the cheap red laser pointers on DX. They use a chip instead of a 5.6mm diode, and a lens that is approx 1/3rd the size of an axiz in diameter ;)
 

Tonka

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I've always wanted to try pull out the lens from one of my many spare microscope objectives...

but they seem to be factory moulded in there so i'm having a bit of trouble...

anyone tried to take out the nice lenses from a microscope objective?
 
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Tonka said:
I've always wanted to try pull out the lens from one of my many spare microscope objectives...

but they seem to be factory moulded in there so i'm having a bit of trouble...

anyone tried to take out the nice lenses from a microscope objective?
the results would be interesting, I'd like to know what would happen...
 
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wannaburn said:
To get a smaller beam in what I have tried is to find a smaller lens that sits just as close to the diode as the acrylic axiz. The smaller the diameter of the lens translates into a smaller diameter beam.

Erm, getting a smaller lens would mean that you're focusing less of the light coming out from the diode.

Getting a smaller beam is not the same as getting a tighter beam. I'm pretty sure that in order to get a tight beam, you'd need two lenses. because light travels in a straight line, you'd need one lens to bend the light inwards, and another to straighten them again. Without the second lens, the beams would cross and start to diverge again.
 

crocie

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uhh, i kinda get what your saying, but i do agree that 2 lens's is definitely a good idea. although it would be a much bigger hassle.
 




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