A modern violet line laser module is typically based on the adoption of an import 405nm semiconductor laser diode with different output power and a qualified glass coated lens or separate crystal lens within different fan angles. It gains ultra high density and highly powerful violet laser light source generation at long extending distance. Owing to its a bit longer wavelength than invisible UV lasers, not as bright as other red, blue or green laser devices, it just provides users quite special line alignment source for precision application and machining use etc.