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Anybody going to the college library for the first time would find it hard to miss the ease in the issuing process at VIT . Not even one swipe and the librarian is spared the tedious account keeping that is so often associated with college and other libraries across Mumbai. Even the seemingly techno savvy colleges in the city use a manually-fed database at best . For all those who still haven’t managed to understand what it is that I am so impressed by ,let me say it is a contraption that we so conveniently fail to realize the importance of even when it does the huge job of cutting down those long queues at the librarian’s desk. I am of course talking about the Barcode Reader.
Ever wondered what it is that makes the barcode reader perform its work so impeccably. The techno-freaks in the campus would, without a doubt ,be pointing towards this little thing we call Lasers. The principle of operation behind the barcode reader is seemingly simple to understand at first (like everything we have learned so far in our years at VIT) but to think there is nothing more to it would be a mistake. Claiming to understand everything about this apparently simple device would certainly leave fuming , all the bright minds around the world working for years to perfect their knowledge of the still developing concept of lasers.
Getting back to the Barcode Reader (BR), so what is the principle behind its working?
Every BR mainly consists of a light source(in some cases- laser) ,a lens and a photo conductor translating optical impulses into electric ones. Along with this there is also the decoding circuitry which analyzes the barcode's image data provided by the photo conductor and sends the barcode's content to the scanner's output port.
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There are mainly four types of barcode readers and the principle of working is different in each case. They are:
Pen Type Readers and Laser Scanners
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Pen type readers consist of a light source and a photo diode that...