unit

Milinch systems are commonly used to represent the density of barcode codes. First, it's comfortable because the value is represented by an integer. Second, the density of barcode codes is usually related to the resolution of the printing device's capabilities, which is usually expressed in dots per inch (dpi). The size of the barcode is very important for it to be read successfully by the scanner. Each type of barcode is defined using the following size parameters:

module

Module parameters (sometimes called "modules" or "X dimensions") indicate the narrowest bar in the barcode. This parameter is related to the barcode print resolution and barcode density. For example, if the narrowest bar is 10 mils, the barcode is printed at a resolution of 10 mils, or the barcode density is said to be 10 mils.

density

Density has two components: barcode graphic density and information density. The mill is used to specify the barcode density.

1 mil = 1/1000 inch

Information density

Information density is the number of characters that can be encoded per inch given a particular X value. The smaller the value of X, the more characters that can be encoded in 1 inch, and the higher the density. The information density of barcodes depends on the character encoding. The fewer bars and spaces required to encode a symbol, the more dense the barcode is.

Graphic density

The graphic density of the barcode is related to the barcode size. For example, for linear barcodes, the finer the stroke, the higher the density (and therefore less space on the barcode). The following table shows the classification of graphic linear barcodes.

Graphic density	Print resolution
Very high density	<4 mill
High density	4 mils .. 6 mils
Medium density	7 mils .. 13 mils
Low density	14 mils .. 20 mils
Very low density	> 20 mils

The above classification is approximate and depends on the type of barcode. For example, a PDF417 10 mil barcode can be considered a high density barcode. However, a 10 mil line code can be recognized as a medium density barcode.

Information density

Information density is the number of characters that can be encoded per inch given a particular X value. The smaller the value of X, the more characters that can be encoded in 1 inch, and the higher the density. The information density of barcodes depends on the character encoding. The fewer bars and spaces required to encode a symbol, the more dense the barcode is.

width

The width of the barcode depends on the graphics and the density of the information. The density is limited by the resolution of the printer and scanner, but the width of the barcode depends on the information density of the selected symbolic. For the same image density, the width of the barcodes for different symbols can be 2-3 times different. The higher the print density of the barcode, the closer it is to the scanner when scanning. Therefore, when scanning from long distances (eg, more than half a meter), the barcode must have a very low density and the barcode width will increase accordingly.

height

For linear barcodes, there is no information in the vertical direction and the height of the code is determined solely by the ease of scanning. Barcodes that are too low are difficult for the scanner to read (it is difficult to aim the scanner so that the scanline intersects all barcode lines). At the same time, if the barcode is too high, the cost of the label will increase (because the label is high). For most linear symbols, the ratio of ratios is usually considered optimal, and the height of the barcode is 15..20% of the width. Barcode height is also important for applications that use multi-beam scanners. For example, symbols such as UPC and EAN are commonly used in transactions and are often read by multi-beam scanners. Therefore, for such symbols, the barcode height will be higher than recommended.

For 2D barcodes, the character height depends on the print resolution you select, the amount of data to encode, and other barcode parameters.

space

This is a very important attribute, especially for linear barcodes. Spacing is the bright area at the beginning and end of the barcode. These are needed for the scanner to identify the barcode border. It's much better if these areas are the same color as the barcode background. For most 2D matrix symbols, the requirements for the existence of free zones are less stringent or nonexistent. Most modern scanners include a more powerful controller and an "intelligent" decoding algorithm to read printed barcodes without blank areas.