Laser weird focus need help.

[deltawars]

Can anyone please help me the beam only focuses at objects around 5cm away.
How can i get it to have a narrower beam over longer distances?
I'm using the lense that came with this host:808nm Laser Module Host/For TO5 9mm Laser Diode w/h 3 elements glass Lens | eBay
do i need to get a new lense because i mean the host was only $5.60?

This is a picture of how far the laser has to be to focus.

and this is a picture of what happens to the beam.

 

[Eudaimonium]

Simply turn the focusing lens clockwise a bit and the focal point will move farther away.

BTW that dot looks faint, is that an IR laser?

 

[deltawars]

I turned the focusing lens until i got the furthest focus which was like 5cm away.
And yes the laser is ir it would be brighter but i'm only using a 0.9a driver

 

[Eudaimonium]

I can still see some room between the focus knob and the Aixiz head, I'm usually able to screw it in all the way on my Aixiz modules. You sure you can't move it bit more?

Unless you have some modifications going on?

Anyway, since it's an IR laser, it's not of too much use to have it's focus farther away. You can't use it as a pointer (unless you have some IR nightvision in mind?), and because of divergence you'll just soon lose burning abilities.

 

[deltawars]

I don't know if its normal but when i screw the focus knob further into the aixiz the distance the laser can focus on gets smaller.

The IR laser is 808nm i don't know if its normal but it gives off a very bright red dot its just that the IR overpowers the color on the camera.

 

[Eudaimonium]

I don't know if its normal but when i screw the focus knob further into the aixiz the distance the laser can focus on gets smaller.

The IR laser is 808nm i don't know if its normal but it gives off a very bright red dot its just that the IR overpowers the color on the camera.

Err... no that is not normal, not by any account - because it defies the laws of physics.

I have no idea... maybe check you don't have your lens in backwards, and if it's a 3-element glass lens make sure it's not missing any elements inside (that is, try a few others).

Other than that, no idea what could cause focal distance to shrink when lens moves closer to diode.

 

[deltawars]

Well the diode was from hong kong so there diodes are probably not perfect.

Ok thanks i will try that tomorrow.Its like 9:30 here and i have to get up really early tomorrow.