Re: RETAIL SCANNERS - RADIATION BURNS

[king@reasoning.com]

>> 
>> The lasers in a POS outlet would be either Class 1 or Class 2.  In 
>> the case of Class 1, the amount of energy it delivers per square mm 
>> is too small to cause thermal damage.  Sit there staring till you die 
>> of boredom.  Class 2 may have suffienient energy, but you would have 
>> to deliberately stare into the beam.  On the positive side, 
>> supermarkets are usually well lit, so the pupil of the eye would be 
>> relatively small, giving a small target for the beam.

This is no protection.

The beam must be small [it has to be narrower than the smallest element of the
bar code to do any scanning] and the pupil doesn't get that small.

>>							  Also, the beam 
>> is usually scanning so that it can read barcodes, so the beam would 
>> sweep across the eye and little energy would be deposited.

This is substantially more important.

And of course the small pupil is illuminated for a shorter time.

-dk