Blu-Ray dot size question

[GooeyGus]

Hi all, this is my first post! I've been lurking for a while and learning a LOT! I have a pretty simple (i think... heh) question.

I recently acquired a ps3 blu-ray laser from "Rubberband" on this forum. I'm really happy with it, he shipped it really fast and it looks to be built very well, I was just wondering about the actual dot size.

Close up, as in 2-3 inches away from an object, the spot is about .2", or about the size of a BB. The diode is in the aixis housing, so i've played with the focusing a bit to where the dot stays about the same size regardless of distance (unless its really really far etc). My question is, is this the size it is supposed to be? is there any way to get it down to a finer point without the dot getting huge a couple feet away or is this just the nature of the beast?

Again, i'm really happy with the laser and will hopefully be using it as a model to begin to build my own!

 

[styropyro]

The dot will always get huge if you use that lens to make it small at one point. But one advantage of the bigger dot up close will mean that your dot will stay a lot smaller at a distance compared to a laser with a naturally thin beam up close.

 

[MarioMaster]

unfortunately DIY reds and blurays have large beam diameters, it's just sort of a fact of life :-/