Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

i got out my box of lenses and built a "optical bench".
Ok, ok, it is only a board, a white shoebox as screen, and a flashlight,
but... better than guesswork.


The results seem very promising. i could reach the required magnification
in a semi-dark room easily with the flashlight brightness through a piece
of paper.

Best seem to be lenses with very short focal lengths (~~~5cm).
I also tried using a mirror to deflect the projection, and it too worked
surprisingly well.

I'm still unsure whether i should make the projection screen above or
below the drilling table. above the table requires big cutouts, but below
would need a semi-transparent projection screen. I guess paper would
work...


One BAD, BAD thing is because of the lens, if you move the board right the
image moves left, and vice versa. same for up/down. But i don't want to
make a more complicated setup with multiple lenses and mirrors and
whatnot. I think one will get used to the reversed movement.

The whole thing will be made from MDF or plywood, not sure if i should try
to seal the dust out or just keep everything open so i can easily remove
the dust.. also, the lens should be mounted in a way that allows to adjust
it, not sure what i will do there..


Well, i'll let you know what i come up with.

ST