Hi,

> Weeks ago  I left  my UV erasable chips under the sun for hours and I did
>not notice any change (even using the magnifier glass someone
>suggested)until they flew away from  my home balcony in 7th floor,just
>because of the wind.

I have always heard that many types of glass do not pass UV well. You may
need to use a UV lens for this instead. Also, the UV focus would be
somewhat closer in toward the lens than the visible light foci.

Sean

+-------------------------------+
| Sean Breheny                  |
| Amateur Radio Callsign: KA3YXM|
| Electrical Engineering Student|
+-------------------------------+
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