Wednesday, 5 October 2011

In Focus

I've finally run out of the plano-convex lenses I bought last year from Surplus Shed. These were great as they had a 50mm or so focal length which resulted in a short IR focus tube. I've ordered some more lenses but these have a FL of 100mm, therefore I needed to re-design the focus tube of my tag guns.

I changed the tube design to be in two parts. One holding the LED mount, endcaps and focus screw. A second tube is designed to slide over the first, but also it can be lengthened/shortened or given a larger diameter to suit the lens being used.







I forced the two parts together in my carpenters vice.

 
The ridges produced by the RepRap process interlock providing a fantastic strong joint. No glue is needed, I'm not going to get these two apart in a hurry.

Here is a complete IR tube kit. These are now available at Tagbits:












3 comments:

Javier Perez Rabasa said...

Hi Tony,

I am also making one of these, but I am still experimenting with the lens. The problem I got is that after choosing the best lens and setting focal length, the accuracy that I get for my "shots" at 22m distance is too bad, about a circle of diameter 65cm.

I would like to know if this is normal accuracy or if for a laser tag accuracy should be better (smaller circle).

How much accuracy does your system have?

Thank you!

Tony said...

Hi Javier,
My posts on optical efficiency
here:
http://lasertagparts.com/forum/index.php?topic=589.msg3345#msg3345
and
here:
http://lasertagparts.com/forum/index.php?topic=337.msg1862#msg1862

may help....

Javier Perez Rabasa said...

Thanks Tony for your help. I will continue experimenting :-)