Barcode fonts
Barcode fonts enable you to print barcodes on graphics printers that can accept fonts (i.e. a Windows supported graphics printer or a PostScript printer which can accept downloaded fonts). Multi-user versions of dLSoft fonts are also licenced for embedding – so that the barcodes may be embedded in web pages or Portable Document Format (pdf) files. (See the application notes on our support website for information about font embedding www.dlsoft.com/support
However, the user needs to be aware of a number of factors that determine whether printed barcodes can actually be scanned correctly.
1. The thickness of bars and spaces in barcodes is important. Some types of barcode use only two thicknesses of bar, others use three thicknesses, and others more. Even when you print a barcode using a dLSoft barcode font, you need to ensure that the barcode has not been printed too small - so that within the resolution of the printer a single thickness bar has been printed at the same size as a double thickness bar. Consequently it is essential that you check that a printed barcode is readable using an appropriate scanner or reader.
Barcodes printed by laser printer will, in general, be printed correctly, but codes printed by matrix printers must be reproduced at a large enough scale that the barcodes unit size is at least as large as the printer's pins.
2. Bar thickness reduction: Most dLSoft barcode fonts are supplied in three bar thicknesses. The Wide font (and its variants - names ending in W) should be suitable for most 600 and 1200 dpi laser printers - it has the bar/space ratio defined at its correct value. The Regular font (names ending in R) has all bars reduced by 8% and will probably be a better choice for 300 dpi laser printers and good quality ink-jets. The Narrow font (names ending in N) has all bars reduced by 16% and is supplied for users who will be creating master copy which will subsequently be printed using a wet ink technique (in which the ink spreads, so making each bar thicker than in the master). The narrow fonts should only be used if you know that a bar thickness reduction is required. Picking the wrong font usually produces unreadable images! If greater control of bar thickness is needed then an image creating system, such as dBarcode, will be required.
3. Many barcode types may use codes only of a specific length. (e.g. EAN13 requires 13 digits in the code – including the mandatory check digit). Some barcode types use specific digits of the code as a checksum - so not every combination of digits can form a legal barcode. dLSoft barcode fonts display as barcode characters the characters you specify. If your barcode type requires start and stop characters and a check digit character you must provide these character within the string of characters you wish to print as a barcode symbol. Furthermore most coding schemes are limited to 32 characters or less. The barcode types support by dLSoft barcode fonts are described in the remainder of this document, along with details of the Start/Stop character and check digit calculations.
4. Users should be aware that it is possible to print barcodes of a specific type and find that normal retail scanners are unable to decode the images. This does not necessarily mean that there is anything wrong with the barcode symbol. Most scanners aimed at the retail market are not programmed to interpret barcode codes reserved for other (e.g. military) use.
5. Space characters are treated as a special case in a number of Windows applications - the font character being ignored and a gap being placed where the space character was expected. In some applications the same behaviour is seen with the non-break space character (ASCII 160). dLSoft barcode fonts that contain a space character reproduce this character at ASCII 159, and this should be used whenever space characters give rise to a gap in barcodes. Even where the space character is not deliberately encoded it may appear as part of a check digit sequence.
6. The ASCII DEL character (ASCII 127) does not appear in the Windows character set. Those barcode fonts that need to use this character may use the repeated character at ASCII 223.
More:
