How small can you make a diode laser spot?

LightBurn Hardware Compatibility
1

I recently got an Ortur Master 20w with the goal of cutting small thin pieces of wood.

When I try to focus down to a dot in order to cut, it turns out that I can narrow the X dimension but not the Y dimension. Here is a test cut where I tweaked the focus every time.

img20200414_22455259
img20200414_224552591499×435 1000 KB

I went back and forth with Ortur and this is what they told me: “This kind of higher power Laser diode is bar-shape, so, when focused well, the laser spot is a 0.5x1mm rectangle.”

This seems way too large for a laser spot. Is this normal for a diode laser?

Just as a comparison, here are two things I made using the Ortur and a local Maker Space CO2 laser.

img20200417_09455598
img20200417_094555982665×1735 1.26 MB

2

They aren’t wrong - high power diodes use a linear array of emitters, so they do produce a rectangular output though the highest power density is usually a small spot in the middle. It’s possible to use some special optics to shape the rectangular beam into more of a square, but that’s expensive.

3

That’s good to know, I guess the diode isn’t defective then. I’m going to try see if I can tweak the settings to get some good part fits.

4

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.