Lightobject.com Support Forum

Hi,
I try to get a very thin focus point and even at 55mm. I can't get better than 0.5mm wide line.
I mean when I move the machine with the laser on...

I did test from 50mm to 60mm making line every 0.1mm so I did 100 lines
I also test with different power and speed and the line still stay
from 0.5 to 1mm wide...

Do you know how to get better than this?
J-P

Let me get some help from "MASTER Rick". If possible, please send me some pictures and I'll forward to the Master

CNCMANIAC wrote:Hi,
I try to get a very thin focus point and even at 55mm. I can't get better than 0.5mm wide line.
I mean when I move the machine with the laser on...
J-P

Hi, the usual lens is plano-convex it can give a 0,3 to 0,5mm spot, it may vary depending on several factors: tube, mirrors alignment ( a smal portion of the beam may be reaching the inner wall of the lens head and being reflected at an angle, this can cause a double spot ) so, check it carefuly.

If you want thinner than that you must get a :
Meniscus Lenses
Meniscus lenses are designed to minimize spherical aberration producing a minimum focal spot size for incoming collimated light.
or a
Aspheric lenses
Aspheric lenses are designed to be diffraction limited. They usually achieve a smaller spot size than both the plano-convex and positive meniscus lens. This provides the highest power density at the lens workpiece with equivalent focal length.

Rick

Thank you for the reply,
As you suggest other lens to get a thinner focus can you point me somes places to get it?

Thanks again,
J-P