New Blu-Rays on KD!

[jamilm9]

well if you checked new wish website it has blue lasers that look like that.I sent them a email.Dealextreme are trying to get them.Go to the 200mw red laser and one question is newish has blue lasers.

 

[ads813]

interesting...... :-?

 

[IgorT]

i thought blu rays could be focused to a tiny dot?

Yes, Blue Rays and all other diode lasers can easily be focused into a tiny dot.

But that doesn't mean the beam is then this thin over it's entire distance. It starts out thick, and goes down to the tiny dot, and expands after that and becomes huge at a distance, depending on how close you focused it.

Look at the attached pics. When you focus the laser, you concentrate the entire energy in that tiny spot. But if you are trying to burn something, you have ti hit the "exact" distance, where the beam is the thinnest. A little off, and the power density is lower. And the closer the focus, the faster the beam spreads after that.

It would be amazing to be able to make the entire beam as thin. It would have the same burning power at any distance. But that is not how it works.