Laser engraving codes are also known as metal engraving codes, laser etching codes, laser jet codes, dot matrix codes, etc. It is a way of marking the bar code on the product by laser engraving. Generally, the DPM (Direct Part Mark) code is used, and the Datamatrix code (DM code) is the most commonly used one. 

(Picture is DPM QR code)

The DM code is a It has the characteristics of high density, small size and large amount of information. It is widely used in the anti-counterfeiting of commodities, small parts identification, circuit board parts, IC anti-counterfeiting, various metal products identification, overall identification and so on.

There are two commonly used laser engraving codes, one is DPM code, the other is Datamatrix code, and in terms of technology, there are etching codes, laser engraving codes, dot matrix codes, inkjet codes, etc. 

The above code system is often used in the manufacturing process for product traceability and process control.