English 
We know that there are many aspects of the machine for engraving that will affect the engraving effect, such as power, speed, blowing, focal length, interval, etc. It can be said that different factors have different effects on engraving. In fact, the power is put in the first place, of course, beca
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The laser is another major invention of the twentieth century after nuclear energy, semiconductors and computers, and is widely used in industrial manufacturing, biomedical and military fields by virtue of its good monochromaticity, directionality and brightness. It is known as the "fastest knife",
