Need help understanding barcode reader operation

  • Thread starter pairofstrings
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In summary, a barcode reader projects a horizontal beam of light on the code and the light is reflected back and captured by the scanner.
  • #1
pairofstrings
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Barcode reader's operation

I see that a horizontal beam of light is projected on the code and then, what happens. Does the light is reflected back and caught somewhere else if so where and what is this collector? How is it reflected back when code is printed on some non-reflecting body?
 
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  • #2
Here's a HowStuffWorks video that turned up when I Googled for "How Stuff Works Barcode Scanners":
http://videos.howstuffworks.com/science-channel/37733-deconstructed-barcode-scanners-video.htm

While it looks like a continuous line (or other pattern), it's actually a single beam of light being rastered (scanned) across the barcode. The photodiode then picks up the reflected light, correlates it back to the scan position, and "reads" the barcode. More at:
http://www.explainthatstuff.com/barcodescanners.html
http://en.wikipedia.org/wiki/Barcode_reader

Some newer scanners take a picture (with a CCD sensor, the same as in a camera), and then analyze that. The natural extension of this is the 2-D barcodes that you see about: those are usually meant to be read by taking a picture with a camera phone, without needing to laser scan the barcode.
 
  • #4
There are bar code reading apps for all (?) smart phones and there are also bar code printing progs. The scanners on checkouts are very good these days and they scan in two directions to get the best signal from anything that looks like a bar code.
 
  • #5
bar code reading apps for all? No. There are different kinds of barcode readers according different platform, such as Java barcode reader, .NET barcode reader, etc. I know a good barcode solution site. It's called onbarcode. It provides various barcode readers and barcode generators. I have used two tools from there. They are as follows:
http://www.onbarcode.com/tutorial/csharp-barcode-create-net-windows.html
http://www.onbarcode.com/tutorial/csharp-barcode-create-asp-net.html
That site is very helpful for barcode creation.
 
  • #6
So my Pentax DSLR could be rung up as a packet of frozen peas? We live in hope.
 

1. What is a barcode reader?

A barcode reader, also known as a barcode scanner, is an electronic device that is used to capture and read information from barcodes. It uses a light source and a photosensitive component to scan the barcode and convert it into a digital signal.

2. How does a barcode reader work?

A barcode reader works by emitting a red light onto the barcode, which reflects back and is captured by the scanner. The scanner then decodes the reflected light and converts it into a digital signal that is sent to a computer or other device for processing.

3. What types of barcodes can a barcode reader scan?

There are several types of barcodes that a barcode reader can scan, including linear barcodes, 2D barcodes, and QR codes. The specific type of barcode that a reader can scan will depend on its capabilities and the type of software it uses.

4. How accurate is a barcode reader?

A barcode reader is highly accurate and can read barcodes with a very low error rate. The accuracy of a barcode reader will depend on the quality of the barcode and the type of scanner being used. Most modern barcode readers have an accuracy rate of 99% or higher.

5. Can a barcode reader be used with any type of barcode?

No, not all barcode readers can read every type of barcode. Some barcode readers are designed to scan specific types of barcodes, while others are more versatile and can read multiple barcode formats. It is important to check the specifications of a barcode reader to ensure it is compatible with the type of barcode you need to scan.

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