This standard specifies the structure, size and technical requirements of the 39 barcode. This standard is applicable to automatic identification in the fields of transportation, warehousing, industrial production lines, library information, medical and health care, etc. GB/T 12908-1991 39 barcode GB/T12908-1991 Standard download decompression password: www.bzxz.net
This standard specifies the structure, size and technical requirements of the 39 barcode. This standard is applicable to automatic identification in the fields of transportation, warehousing, industrial production lines, library information, medical and health care, etc.

National Standard of the People's Republic of China
39 bar code
Subject content and scope of application
This standard specifies the structure, size and technical requirements of the blue nine bar code. GB/12908-91
This standard is applicable to automatic recognition in the fields of transportation, warehousing, industrial production lines, books and documents, medical and health care, etc. 2 Reference standards
GB12053 Alphanumeric character set for optical recognition Part 1: OCR-A character set Shape and size of printed images GB12508 Alphanumeric character set for optical recognition Part 2, OCR-B character set Shape and size of printed images GB12905 Bar code system general terminology Bar code symbol terminology 3 Structure
39 bar code is a non-continuous, non-fixed-length, bidirectional bar code with self-checking function, which consists of bar code characters and corresponding characters for human recognition.
3.1 Composition
The 39 barcode consists of a left blank area, a start symbol, a data symbol, a terminator, and a side blank area. Each barcode character consists of nine units, five barcodes and four blank units, two of which are wide units (expressed by hexadecimal 1\), and the rest are narrow units (expressed by binary system *0\), see Figure 1.www.bzxz.net
Figure 1 shows the barcode of B2C3
3.2 Character set
The character set of the 39 barcode is as follows,
a. Numbers 0~-9,
b. Alphabets A~z;
special characters
一(minus sign);
·[dot);
(space;
*(asterisk):
$(dollar sign);
State Administration of Technical Supervision, approved on May 17, 1991, January 1, 1992
slash):
+(plus sign),
%(percent sign).
3.3 Characters, barcode characters and binary representation GB/T 12908-91
3. 3. T The symbols, barcode characters and binary representation of the 39 barcode are shown in Table 1. Table 1 Comparison table of characters, barcode characters and binary representation Characters
Barcode characters
Binary representation
* (asterisk) is only used as the start character and the end character. Characters
Barcode characters
Binary representation
4 Technical requirements
4.1 Density, size and tolerance of barcode symbols 4.1.1 Density
GB/T 12908—91
Depending on the resolution of the scanner and the requirements of printing error, the density of the barcode symbol can vary within a certain range. See Table 2. Table 2 Density, size, and allowable error of the 39 barcode Narrow unit width
4.1.2 Size
Wide unit width
Bar width ratio
Allowable error of bar (space) width
±0,175
4.1.2.1 The bar (space) width of the 39 barcode symbol is shown in Table 2. The minimum width of the pattern unit is 0.191 mm. 4.1.2.2 The width-to-pattern ratio is generally 2~3. If the narrow unit width is less than 0.508mm, the width-to-narrow ratio should be greater than 2.2. 4.1.2.3 The size of the barcode character spacing is selected between 1 and 3 times the narrow unit width. Barcode symbol density
1/(25.4 mum)
4.1.2.4 The bar height of the barcode symbol is variable. The minimum bar height shall be 15% of the length of the bar code symbol, but shall not be less than 6.4mm. 4.1.2.5 The minimum width of the blank area shall be 10 times the width of the narrow unit of the bar code symbol, but shall not be less than 2.5mm. For bar code symbols read by optical scanners, the width of the blank area shall not be less than 6.1mm. 4.1.3 Allowable error of bar (space) width
The allowable error of the bar (space) width of the 39 bar code symbol is shown in Table 2. 4.2 Reflectivity
4.2.1 Base measurement method
The reflectivity is measured with a peak wavelength of 633nm and a bandwidth equal to or less than 120nm (relative to 50% of the peak value) as the light source. The incident light should be 45° to the normal of the base surface. The collection of reflected light should be within a range of 15° centered on the normal. The spot diameter of the measuring instrument shall not be greater than 0.8 times the narrow unit width.
4.2.2 Reflectivity requirements
4.2.2.1 Minimum reflectivity of space
a. For bar code symbols with narrow cell width greater than 0.508mm, the reflectivity Rc. of space should be greater than 25%; b. For bar code symbols with narrow cell width equal to or less than 0.508mm, the reflectivity RL of space should be greater than 50%. 4.2.2.2 Maximum reflectivity of bar
The maximum reflectivity of the bar is a function of the reflectivity Rr. of space, see Table 3. The minimum ratio of R to is 4.0. 4.2.2.3 PCS value
Reflectivity of space
GB/T 12908-91
Allowable reflectivity value of Table 3
The definition of PCS value is: PCS blue
The minimum PCS value is 75%.
4.3 Spots and de-inking
Spots and de-inking shall meet one of the following requirements: Spots and de-inking shall not exceed the maximum reflectivity of the bar
h, spots and de-inking shall not exceed 25% of the area within a circle with a diameter of 0.8 times the width of the narrow unit. 4.4
Characters for human recognition
Characters for human recognition shall preferably use the OCR-A character set or the OCR-B character set. Any character with a height of not less than 2.3B mm can be used. 5 Technical indicators of original film
The allowable error of the bar (space) width in the original film of the barcode symbol is 5% of the printing allowable error (generally controlled within the range of 0.005~0.013 mm).
6 Quality Assurance
6.1 Inspection of Original Film
Inspection of barcode symbols on original film shall include: checking whether information decoding and bar (space) width meet the allowable error of film size. 6.2 Inspection of Barcode Symbol Printing
Inspection of barcode symbol printing shall include: checking whether information decoding, PCS value and reflectivity, and size error meet the requirements of this standard. A1 Check Character Calculation Method
GE/T12908—91
Appendix A
Check Character Calculation Method
(Supplement)
Sanjiu barcode has self-checking function, so check characters are not used in general. In order to meet the requirements of data accuracy in specific applications, additional check characters can be used.
The 39 barcode uses modulo 43 checksum. The calculation method is as follows: Code: 12345/ABCDE
Calculate the sum of each character value (see Table AI for code character values): 1+2+3+4+5+40+10+11+12+13+14=115 Divide the sum of the character values ​​by modulo 43 and take the remainder. b.
11543-2-29
From Table A1, find the character corresponding to the remainder 29, which is T. The code including the checksum character is: 12345/ABCDET. Table AI 39 barcode character value allocation table
Character value
Character position
Additional instructions:
This standard is proposed by China Article Coding Center. 91
GB/I12908-
This standard is drafted by China Article Coding Center. The main drafters of this standard are Zhao Nan, Hao Hailian, Zhou Gang, Zhang Chenghai,
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