Barcode scanners can be quite simple devices comprised of a light source, a photo diode and a simple decoder or complex CCD or camera based scanners. Learn how barcode scanners work and how to scan bluetooth barcode into a computer.
There are actually currently four several 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 contain a light source along with a photo diode which can be placed next to each other inside the tip of the pen or wand. To read through a barcode, you drag the tip in the pen across every one of the bars inside a steady even motion. The photo diode measures the intensity of the light reflected back through the source of light and generates a waveform that is utilized to measure the widths in the bars and spaces from the barcode. Dark bars inside the barcode absorb light and white spaces reflect light so that the voltage waveform generated by the photo diode is undoubtedly an exact duplicate of the bar and space pattern in the barcode. This waveform is decoded with the scanner inside a manner the same as the way Morse code dots and dashes are decoded.
Laser scanners work much the same way as pen type readers although they utilize a laser beam as the light source and typically employ either a reciprocating mirror or a rotating prism to scan the laser beam forward and backward over the barcode. Just just like with the pen type reader, an image diode is utilized to study the intensity of the lighting reflected back from the barcode. In pen readers and laser scanners, the light emitted with the reader is tuned into a specific frequency and also the photo diode was created to detect only this same frequency light.
Pen type readers and laser scanners can be bought with assorted resolutions to allow them to read barcodes of various sizes. The scanner resolution is measured by the actual size of the dot of light emitted through the reader. The dot of light should be equal to or slightly small compared to the narrowest element width (“X” dimension). In the event the dot is wider than the width of the narrowest bar or space, then a dot will overlap 2 or more bars at any given time thereby resulting in the scanner to struggle to distinguish clear transitions between bars and spaces. If the dot is just too small, then any spots or voids from the bars could be misinterpreted as light areas also making ring barcode scanner unreadable. The most popular X dimension is 13 mils (roughly 4 printer dots over a 300 DPI printer). Because this X dimension is indeed small, it is quite critical that the barcode is made having a program that produces high resolution graphics (like B-Coder).
CCD (Charge Coupled Device) readers use an array of hundreds of tiny light sensors lined up consecutively from the head in the reader. Each sensor can be looked at as just one photo diode that measures the power of the sunshine immediately in front of it. Every individual light sensor in the CCD reader is incredibly small and because there are a huge selection of sensors lined up in a row, a voltage pattern identical to the pattern in a barcode is generated in the reader by sequentially measuring the voltages across each sensor within the row. The main distinction between a CCD reader along with a pen or laser scanner is the fact that CCD reader is measuring emitted ambient light from your barcode whereas pen or laser scanners are measuring reflected light of your specific frequency caused by the scanner itself.
The 4th and newest type of barcode reader currently available are camera based readers which use a small camera to capture a graphic of any barcode. The reader then uses sophisticated digital image processing solutions to decode the barcode. Video cameras use the same CCD technology as in a CCD barcode reader other than rather than possessing a single row of sensors, a video camera has countless rows of sensors arranged inside a two dimensional array to enable them to generate a graphic.
The standards which make a barcode readable are: a satisfactory print contrast between your light and dark bars and getting all bar and space dimensions in the tolerances for the symbology. Also, it is important to have sharp bar edges, few or no spots or voids, an easy surface and clear margins or “quiet zones” at either end in the printed symbol.
All application programs support barcode reading so long as you get the right equipment. Barcode readers are offered 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 computer plus they offer a pigtail connector to enable you to plug in your keyboard concurrently. Once you scan a barcode together with the keyboard wedge barcode reader, your data goes into the pc equally as if this were typed in on the keyboard. It is then extremely easy to interface the barcode reader to the application that is certainly written to accept keyboard data.
The keyboard wedge interface is extremely simple however it has a few drawbacks. If you swipe a barcode, the cursor has to be in the correct input field in the correct application otherwise you find yourself reading barcode data into whatever application has got the focus. This can cause all kinds of potential problems as you can imagine. The keyboard output is also limited in this you are unable to modify the information in any respect before sending it into the program that is to obtain the data. For instance, should you necessary to parse a barcode message into multiple pieces or remove some of a barcode message or add in the date or time stamp you would probably not be able to using a normal keyboard wedge reader.
The other possible output option is to obtain a barcode reader with the RS232 or “Serial” interface. With these kinds of barcode readers, you connect the reader with an available serial 65dexqpky on the back of your personal computer. You will then want a program known as a “Software Wedge” to accept the data in the barcode reader and feed it towards the application the place you want the information to go. The problem with this approach is that it is a bit more technical nevertheless you gain considerably more control of how and where your information ends up once you read moto z barcode.
Our WinWedge product line is designed just for this reason. WinWedge is surely an executable program that will pass serial data backwards and forwards to other programs using either DDE (Dynamic Data Exchange) or by converting incoming serial data to keystrokes (i.e. it stuffs the keyboard buffer together with the incoming serial data). With WinWedge, you can control specifically where the information goes into the objective application and you will also perform all kinds of modifications around the data before it really is delivered to the application form including parsing or translating the information and also adding additional keystrokes or date and time stamps to the data.
WinWedge is very simple to use and was designed to do you have up and running sending and receiving serial data straight from within your application with a short while. Because WinWedge can pass data using DDE, it is possible to set your application as much as insure the barcode data always goes where it should really go and you could likewise have your application running from the background and still accept barcode input when you run various other program inside the foreground. WinWedge is without question one of the most robust way to interface a barcode reader to your PC using the least amount of effort.