United States.
Bar code technology was first produced in the turbulent 1920s, and was born in the laboratory of Westinghouse. An eccentric inventor named John Kermode "whimsically" wanted to automatically sort postal documents. At that time, every idea about the application of electronic technology was very novel.
His idea was to mark the envelopes with a barcode. The information in the barcode was the recipient's address, much like today's postal code. For this reason, Comand invented the earliest barcode identification. The design scheme is very simple (note: this method is called the module comparison method), that is, one "bar" represents the number "1", and two "bars" represent the number "2". ”, and so on.
He then invented a barcode reading device consisting of basic components: a scanner (capable of emitting light and receiving reflected light); a method of measuring reflected signal bars and spaces, known as edge positioning The coil; and the method of using the measurement results, i.e. the decoder.
Extended information:
Development history
It was not until 1949 that the patent documents of Norm Woodland and Bob There is no record of barcode technology in patent documents before Bernard Silver invented the omnidirectional barcode symbol, and there is no precedent for its practical application.
Norm Woodland and Bernard Silver's idea was to take Command and Young's vertical "bars" and "voids" and bend them into loops, very much like Archery target. In this way, the scanner can decode the barcode symbol by scanning the center of the pattern, regardless of the direction of the barcode symbol.
It wasn’t until 1970, when Iterface Mechanisms developed the “QR code”, that there were printing and reading equipment for two-dimensional matrix barcodes that were affordable for sale. At that time, two-dimensional matrix barcodes were used to automate the typesetting process in newspapers.
The two-dimensional matrix barcode is printed on paper tape and scanned and read by today's one-dimensional CCD scanner. The light from the CCD shines on the paper tape, and each photocell is aimed at a different area of ??the paper tape. Each photocell outputs a different pattern depending on whether the barcode is printed on the paper tape, and the combination produces a high-density information pattern.
Baidu Encyclopedia-Barcode