--- In
Homebrew_PCBs@yahoogroups.com, James <bitsyboffin@...> wrote:
>
> On 06/07/13 15:05, arvidj01 wrote:
> >
> >
> > Any thoughts based on your experiences would be appreciated, including
> > "Your are over thinking this! Just build the d..n box.".
> >
>
> For hobby purposes, this.
>
> If you use LEDs, just do a quick check that your led spacing and
> distance to your artwork from the leds does not introduce dead spots,
> that is, make sure the viewing angles of adjacent LEDs overlap at or
> just before the artwork.
>
> Dead spots will make the box useless for everything, while poor/no
> collimation won't have an effect unless you're really pushing the
> boundaries of hobby exposure in my opinion.
The UV LED's on eBay seem to come in two flavors:
narrow angle, about 20 to 25 degrees
wide angle, about 150 to 160 degrees
It would seem like the wide angle version would mitigate the dead spot issue at the expense of needing more LED's to make up for the lack of focus ... no pun intended ... of the energy by the wide angle.
My thought is that a large number of wide angle LED's would provide a very even ... but also extremely non-collimated ... UV source.