Barcode scanners can be quite simple devices consisting of a light source, a picture diode plus a simple decoder or complex CCD or camera based scanners. Understand how barcode scanners work and the ways to scan bluetooth barcode right into a computer.
You can find currently four different types of barcode scanners available. Each works with a slightly different technology for reading and decoding a barcode. There are actually pen type readers (i.e. barcode wands), laser scanners, CCD readers and camera based readers.
Pen type readers include a mild source along with a photo diode that are placed next to each other from the tip of your pen or wand. To read through a barcode, you drag the tip of the pen across all the bars within a steady even motion. The photo diode measures the power of the lighting reflected back from the light source and generates a waveform that is used to appraise the widths of the bars and spaces from the barcode. Dark bars within the barcode absorb light and white spaces reflect light so that the voltage waveform generated with the photo diode is an exact duplicate of your bar and space pattern inside the barcode. This waveform is decoded with the scanner inside a manner similar to the way Morse code dots and dashes are decoded.
Laser scanners work exactly the same as pen type readers except that they use a laser beam because the light source and typically employ either a reciprocating mirror or perhaps a rotating prism to scan the laser beam forward and backward throughout the barcode. Just exactly like using the pen type reader, an image diode can be used to appraise the power of light reflected back in the barcode. Within both pen readers and laser scanners, the light emitted by the reader is tuned to some specific frequency as well as the photo diode is designed to detect only this same frequency light.
Pen type readers and laser scanners can be acquired with various resolutions to allow them to read barcodes of several sizes. The scanner resolution is measured by the dimensions of the dot of light emitted from the reader. The dot of light needs to be similar to or slightly small compared to the narrowest element width (“X” dimension). In the event the dot is wider in comparison to the width in the narrowest bar or space, then the dot will overlap two or more bars at a time thereby creating the scanner to be unable to distinguish clear transitions between bars and spaces. When the dot is too small, then any spots or voids inside the bars can be misinterpreted as light areas also making wearable scanner unreadable. One of the most commonly used X dimension is 13 mils (roughly 4 printer dots on a 300 DPI printer). Simply because this X dimension is indeed small, it is extremely important that the barcode is produced having a program that creates high resolution graphics (like B-Coder).
CCD (Charge Coupled Device) readers use a wide range of a huge selection of tiny light sensors arranged in a row within the head in the reader. Each sensor can be considered to be a single photo diode that measures the concentration of the sunshine immediately before it. Every person light sensor inside the CCD reader is extremely small, and because there are hundreds of sensors lined up in a row, a voltage pattern identical to the pattern inside a barcode is generated within the reader by sequentially measuring the voltages across each sensor from the row. The key difference between a CCD reader plus a pen or laser scanner is the fact that CCD reader is measuring emitted ambient light in the barcode whereas pen or laser scanners are measuring reflected light of your specific frequency caused by the scanner itself.
Your fourth and newest sort of barcode reader now available are camera based readers that use a small video camera to capture an image of a barcode. Your reader then uses sophisticated digital image processing techniques to decode the barcode. Video cameras take advantage of the same CCD technology like in a CCD barcode reader except that as opposed to developing a single row of sensors, a youtube video camera has numerous rows of sensors arranged in a two dimensional array so they can generate an image.
The factors which make a barcode readable are: a sufficient print contrast between your light and dark bars and getting all bar and space dimensions throughout the tolerances to the symbology. It is also beneficial to have sharp bar edges, few or no spots or voids, an effortless surface and clear margins or “quiet zones” at either end of the printed symbol.
All application programs support barcode reading so long as you possess the right equipment. Barcode readers can be purchased with 2 kinds of output – either “keyboard wedge” output or RS232 output. The barcode readers with keyboard wedge output plug into the keyboard port on your hard drive additionally they supply a pigtail connector to be able to connect your keyboard as well. Whenever you scan a barcode together with the keyboard wedge barcode reader, the information goes into your computer just as when it were typed in around the keyboard. This makes it extremely simple to interface the barcode reader to the application which is written to simply accept keyboard data.
The keyboard wedge interface is extremely simple however it has a few drawbacks. If you swipe a barcode, the cursor needs to be from the correct input field from the correct application otherwise you wind up reading barcode data into whatever application has got the focus. This can cause all sorts of potential problems obviously. The keyboard output also is limited for the reason that you can not modify the info in any respect before sending it to the program that may be to get your data. For example, when you found it necessary to parse a barcode message into multiple pieces or remove a few of a barcode message or add in a date or time stamp you would struggle to by using a normal keyboard wedge reader.
Another possible output option is to get a barcode reader by having an RS232 or “Serial” interface. With these sorts of barcode readers, you connect the reader for an available serial 65dexqpky on the rear of your PC. You might then need a program called a “Software Wedge” to accept the data from the barcode reader and feed it to the application where you want your data to look. The problem with this strategy is it is a touch more technical nevertheless you gain considerably more power over how and where your data ends up whenever you read barcode sled.
Our WinWedge product line is designed just for this reason. WinWedge is undoubtedly an executable program that will pass serial data forward and backward to many other programs using either DDE (Dynamic Data Exchange) or by converting incoming serial data to keystrokes (i.e. it stuffs the keyboard buffer with all the incoming serial data). With WinWedge, you can control precisely where the info goes into the prospective application and you will also perform all kinds of modifications in the data before it can be shipped to the applying including parsing or translating your data in addition to adding additional keystrokes or date and time stamps on the data.
WinWedge is incredibly easy to use and was designed to do you have working sending and receiving serial data right from in your application in just a short while. Because WinWedge can pass data using DDE, it is possible to set your application approximately insure that this barcode data always goes where it should really go and you can likewise have your application running within the background still accept barcode input when you run some other program in the foreground. WinWedge is without question one of the most robust approach to interface a barcode reader to some PC with all the least amount of effort.