Barcode Glossary P


Barcode-Glossary P

  • Picket Fence Orientation

  • Specifies a barcode symbol with the axis of the bars oriented vertically so that a horizontal scanner beam can pass the entire symbol.
    Compare: "Ladder Orientation".

  • Print Contrast Signal (PCS)

  • PCS is the abbreviation for “Print Contrast Signal". A measurement for the relative difference of the reflectance between light and dark elements (in the following formula RL (for the light) and RD (for the dark elements)):
    PCS = [ (RL - RD) / RL].

  • Print Density

  • The print density defines how the barcode is displayed in relation to the module width x. The following terms are used:
    Ultra High Density - x smaller than 0.19 mm
    High Density - x between 0.19 mm and 0.24 mm
    Medium Density - x between 0.24 mm and 0.30 mm
    Low Density - x between 0.30 mm and 0.50 mm
    In case of large distances - x larger than 0.50 mm

  • Print Character Set

  • A firmly defined character scope firmly defined under this name that can be loaded on printers and that can be addressed via control characters and code. A printer character set can, among other barcode characters of a certain barcode symbology, contain human readable text (visually readable characters) and/or blanks. Printer character sets can be determined according to various different aspects.

  • Print Direction

  • The direction in which the printed matter (e.g. paper) runs though the output device (e.g. printer).

  • Print Quality

  • The congruity of a printed optical symbol with the relevant specified requirements, such as measurements, reflectance, edge sharpness, spots, flaws etc., that together influence carrying out the reading process. The better the print quality of the barcode symbol, the easier and safer the readability of the barcode. To be able to check the print quality, the manufacturers of barcode reading devices are offering various different test devices.

  • Printability Test

  • A test for checking the print quality.

  • Printer Resolution

  • See "Resolution".

  • Printer Commands

  • See also "Printer Control Sequences".

  • Printer Control Sequences

  • Apart from the actual print data, the printer receives from the system also special characters and sequences. All control characters and sequences of a printer form the command set. The commands can be separated into the following function groups: ·Commands for the page control, determining the paper format, the paper feed as well as paper edges and the row pitch.
    · Commands for the cursor positioning, carried out by CR, LF, FF and tabs.
    · Commands for the font definition, such as font selection, orientation (portrait, landscape), attributes (bold, italic, wide, etc.), font quality.
    · Graphic commands, such as resolution, graphic data format and color commands for color printing.
    Out of all the information the program receives from the user via the barcode, the Visual Bar Code Designer creates a command sequence (in the PCL and PostScript format), with which the printer, equipped with a barcode SIMM/DIMM, prints the corresponding barcode.

  • Printing Tolerance

  • See "Tolerance".

  • Parity

  • A system for the encoding of character as “uneven“ (with an uneven number of binary Ones within the structure) or as “even“ (with an even number of binary Ones within the structure). This is used as a self-check mechanism for barcodes. A parity-bit (parity bar or module) can be contained in an encoded character in order to set the sum over all bits always on “even“ or always on “uneven“, which serves as a basic checking process.

  • PCL

  • Hewlett Packard has developed a printer language called PCL (Printer Control Language) that provides a mutual command set for the printing output on different printers. PCL defines a standard for the printer functions and the call-up of these functions in application programs. The PCL-printer language was continually developed further over a longer period. The result are five large function packets building up upon each other and taking into consideration all novelties in printing technology and application software as well as the ever-changing user requirements.

  • PCL Steuersequenz

  • See "PCL".

  • PDF417

  • See "PDF 417".

  • Pixel

  • The smallest image element forming, in combination with other elements, a complete graphic. With the aid of certain programs, a single pixel can be made visible on the screen, deleted or added (from "picture element" = image element). Barcodes, which can be displayed on the screen by the Visual Bar Code Designer consist of pixels that, however, cannot be altered again.

  • Plessey Code

  • The character set of the Plessey-Code compasses 16 characters (10 digits, 6 special characters). Each character consists of four bits.


  • The POSTNET Barcode (POSTal Numeric Encoding Technique) was developed for the United State Postal Service (USPS). It enables the ZIP Code and further information (e.g. ZIP+4) to be encoded in form of a 2-state barcode (bars with full height and bars with half the height).
    See Chapter: "POSTNET".

  • PostScript

  • PostScript is a device and program independent Seitenbeschreibungssprache with cleartext commands. With the aid of PostScript, more complex graphics and numerous font types of all sizes and characteristics can be printed out via laser printer with e.g. 300 dpi as well as via the exposure units of phototypesetters with e.g. 3.500 dpi. PostScript was developed by John Warnock and Chuck Geschke, the founders of Adobe Systems Inc. The Visual Bar Code Designer generates PostScript commands for Lexmark printers that are equipped with a Lexmark Bar Code SIMM.

  • PWM

  • Pulse width modulated (PWM) codes represent each bit of information by a bar/space pair. A zero bit consists of a narrow bar followed by a wide space, while a One bit consists of a wide bar followed by a narrow space.
    Each decimal digit is represented by a binary code decimal (BCD) number consisting of four bits. For example, the digit 1 has the bit string 1000 and the digit 7 has the bit string 1110.
    See Chapter: "MSI Code".