Hi bailey111
Evidentally, "yes", with a CCD scanner and you'll need to adjust the
font size to get a size that is large enough. The following two links
give good explanations, please click on the links for full details.
BarCode 1 FAQ
Can I Read A Barcode Image Off An LCD Or CRT Screen?
"Believe it or not, yes! I did not believe it until I tried it. You
need to use a CCD barcode scanner, not a laser scanner. You also have
to play with the font size and get a size that is big enough.
The reason a CCD scanner will work and a laser scanner will not is as
follows. A CCD scanner has a video camera that takes a picture of the
entire barcode. A laser scanner scans a beam of laser light across the
barcode and picks up light reflected by the white areas of the
barcode. The ?white? areas of a barcode on a computer display are not
reflecting light but rather are emitting light. Therefore, a laser
beam cannot be scanned across the barcode and the laser scanner cannot
pick up reflected light from the ?white? areas. In fact, the laser
light will be equally reflected by the surface of the computer screen
and the laser scanner will not detect any barcode on the screen."
http://www.adams1.com/pub/russadam/faq.html
Reading a Bar Code from a Computer Screen
"It is entirely possible to read bar codes directly off a computer
screen however there are a few technical issues and requirements that
must be considered."
" First of all, the resolution of most computer screens is too low to
render a readable bar code if the standard bar code dimensions are
used. The width of the smallest bar or space in a normal sized bar
code is on the order of 13 mils wide yet the screen resolution of most
computer monitors is typically 72 dots per inch or 13.88 mils per
pixel..."
" Secondly, there are several different types of bar code readers on
the market including wands, laser scanners, CCD readers and camera
based readers. The only types that can successfully read a bar code
off a computer screen are CCD readers and camera based readers..."
http://www.taltech.com/resources/intro_to_bc/bcompscr.htm
Additional Links of Interest
DealTime
http://www.dealtime.com/xPP-Barcode_Scanners
BizRate
http://www.bizrate.com/ratings_guide/listing__cat_id--11000100.html
Epinions
http://www.epinions.com/Barcode_Scanners
I was happy to find this for you, it was an interesting question. If
you have any questions, please post a clarification request and wait
for me to respond before closing/rating my answer.
Thank you,
hummer
Google Search Terms Used:
barcode scanner computer screen
barcode scanner computer screen ccd |
Clarification of Answer by
hummer-ga
on
29 Jul 2005 15:43 PDT
Hi bailey111,
Yes they are prevalent and you can probably easily find one being used
locally at a "point of sale" check-out counter. So to answer your
question about what company uses them, I would say any company with a
retail outlet.
CCD Barcode Reader
"A CCD barcode scanner can to read bar codes quickly and easily. But
it has two primary limitations. First, it has a short "read" range,
and must be held no more than 1 to 3 inches from the bar code.
Further, the CCD has a limited width, and will not read bar codes that
are wider than the face of the scanner. It is largely popular for use
in point of sale applications."
Laser Barcode Scanner
"This is the most popular bar code scanner. A laser bar code scanner
need not be close to or touch the bar code to do its job. A standard
range laser bar code scanner can read a bar code from about 6 to 24
inches away, and a long range scanner can read bar code from about 2
to 8 feet away. An extra long-range scanner can read a bar code 30
feet away..."
http://www.semicron.com/scannertips.html
Cheers,
hummer
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