@dan has mentioned this is a feature planned for the future on occasion. And a few applications have been mentioned here and there. I am curious what other ideas people have, and want it all in one location for future reference when the feature exists.
First off, what does defocusing mean?
–There is a lens which puts all the power of the laser in one tiny spot. That is why a 45W laser, which is delivering the same power into the world as a 45W light bulb, can cut materials. Because instead of general power to everywhere around it, this is power highly focused in one tiny area. When you de-focus, that means you are moving away from that focal point, to somewhere that the power is more spread out. So you no longer can get as high of a power at one specific point, instead it is spread across an area.
- Cooking Food (I think specifically Bacon was mentioned)
- Heating Acrylic (you would do this so you can fold it, but this requires a larger void inside the laser cutter so you can flip over what you are working on)
Random ideas I have had which spurred making this thread in the first place:
- Finishing 3D prints. With ABS you can use boiling Acetone to vapor smooth a print, this makes it glossy and awesome, nobody can tell it is 3D printed (or at least it is much harder to see it was). There are some people who have listed chemicals that should do the same with PLA, but I haven’t thus far tried it. But… with a defocused laser, you could heat the plastic up and achieve the same results.
- Charring - After making a cut, or in lieu of one, you can char the material to get different colors. In fact, with the laser being able to adjust power settings and focal plane on the fly… you should be able to char with calligraphy level of brushstroke variation.
- Larger Kerf - Defocusing means less power per spot of material. But if your material only needed 10% power to cut anyway, then being defocused to a fair extend still cuts the material. So with easier to cut materials, you can have different line thickness cuts (again… calligraphy applications, and other I am sure)
- Hemispherical divots - Essentially a copy of the third idea here. But without moving around. Keep the laser in one spot, and draw the focal plane back, while delivering enough power to burn away a layer of material. This will engrave the center deepest, and less total material loss as you move out from that point. This may be an extreme fire risk though.
- Plastic Welding - You could apply iron on stickers, or you could seal the edges around a custom shaped balloon.