> >    I worked with some of these barcode sensors and I think that they
have
> >too litle depth of view to be usefull in you application. It has the
emitter
> >and a phototransistor or photodiode and lenses in a TO5 can. They are
made
> >to stay in very close focus all the time..
>
> The HP HEDS units are made for non-contact.  You can turn them into
contact units with a spherical lens.

    Yep.. But the depth of view is very short and well defined. The depth of
focus is something like 1 mm or close to that and the variations of absolute
valeus is huge even inside this depth.. It is ok for barcodes but not for
much else....

Best regards,
Alexandre Guimaraes

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