Small holes

[Starlord]

I have searched and while educational I still do not have the answers I need.

What I am looking to do is to burn holes around 15um in a variety of thin materials, perhaps 100um thick.

Can a m140 be focused to a spot that small?


Can it do a pulse in the ms or perhaps even us range?

I have a m140 from DTR and have built a driver. Still waiting on the goggles.

 

[Cyparagon]

What I am looking to do is to burn holes

Why? Tell us more about your project, please.

 

[Trevor]

That's certainly vague... "a variety of thin materials?"

See Cyparagon's signature for guidelines on getting this figured out.

Trevor

 

[Leodahsan]

Isn't the minimum focus size related to the laser die size? 15um is a little small, iirc bigger than the front facet on m140 emitters...

 

[Starlord]

Well it started out looking at the possibility of using ultrasonics for vaping, electronic cigarettes. Myth has it that the first e-cig was U/S. But after a lot of searching a believe that the U/S was used a a pump and not a vaporizer. And it is unclear if that version was ever built. But in my searching I ran across a new technology, vibrating mesh. This uses a flexible membrane attached to a piezo transducer. It forces out microscopic particles of liquid. Long story short, I became obsessed with making those peckish little holes. As I was already thinking about a CNC burner I decided to jump in.

I have searched and while educational I still do not have the answers I need.

What I am looking to do is to burn holes around 15um in a variety of thin materials, perhaps 100um thick.

Can a m140 be focused to a spot that small?


Can it do a pulse in the ms or perhaps even us range?

I have a m140 from DTR and have built a driver. Still waiting on the goggles.

Why? Tell us more about your project, please.

 

[Lazerbeak]

Hmm... Interesting Starlord Hope you are successful.

--~ LB

 

[Starlord]

Yes I saw it many times in my searching. It had an influence on my post.

As to what I plan to put the holes in, that is very much a open question. I will probably start with piezo film. Ceramic transducers are also a possibility. As is plastic, metal, and who knows what.

That's certainly vague... "a variety of thin materials?"

See Cyparagon's signature for guidelines on getting this figured out.

Trevor

 

[Starlord]

You are asking me? I come before you as a seeker of knowledge. Not the purveyor of such.

In other words I have no clue.

Isn't the minimum focus size related to the laser die size? 15um is a little small, iirc bigger than the front facet on m140 emitters...

 

[Trevor]

Well dang, I think that's the first time I've seen someone asking a massively vague question follow up with a detailed, well-written answer.

Do these holes need to be fairly round, or just... holes?

Trevor

 

[Starlord]

I the closer to round the better. Might not matter too much if they are slightly oblong.
Who knows square might even work. But I do not to even want to think about going there.

Well dang, I think that's the first time I've seen someone asking a massively vague question follow up with a detailed, well-written answer.

Do these holes need to be fairly round, or just... holes?

Trevor

 

[DrSid]

You can focus laser to smaller dot then chip front size, that is not a problem. The formula to get minimum possible dot size at given distance is surprisingly simply divergence * distance, and divergence is wavelength / aperture size.
You can increase aperture size at will, and you can also decrease distance at will to some degree. The only limiting factor will wavelength of the laser. Even theoretically you can't get dot smaller than that. But here we are talking about roughly 30 times of wavelength, I guess it's doable.
Anyway .. 405nm would be a lot better choice. It is designed to burn little holes.

EDIT: btw. why not use DVD burner head, it has diode, optics, even driver.

 

[Sigurthr]

On the subject of minimum spot size theoretically possible; there was recently an article about overlaid coaxial laser beams which cause optical interference with each other at all but the center of the spot allowing for an even small effective spot size than wavelength would allow.

re: the topic at hand; if you've only got access to cheap hobbyist friendly lasers try a 12X S0J6 diode as it is single mode and easier to focus to a tight spot. If you've got a decent budget behind you then look into q-switched Nd:YAG lasers; these can be pulsed for high instantaneous power levels which will "punch" tiny holes in a variety of materials. With CW diode lasers you're going to run in to problems such as thermal stresses, heat affected zones, and restriction of work materials.

 

[sarbanes]

Dr's drilled tiny holes in my dad's eye to re-leave over-pressure from is glaucoma condition. I think a special small telescope, in which the laser is pointed in (into the reverse end) may be what you are looking for. Optics are not easy at this level.