ELAS
ELAS Ltd, Lithuanian based company, develops and manufactures custom laser micro machining systems. The team of engineers and researchers implement scientifically proven processes for industrial production.
Few recent examples are ablation of tungsten carbide and cutting of silicon.
Process for ablation of tungsten carbide with picosecond DPSS laser has been developed for the customer working in hydro turbine industry. Ablation of precise 5 µm depth patterns over large areas with roughness below 600 nm well illustrates potential of this technology.
For a customer electronics industry ELAS has refined silicon cutting technology and implemented in VENTU workstation. Using 20W fiber laser, silicon wafer cut-through capability was increased from 600 µm to 1200 µm. The result has increased total process speed and precision, as operator does not need to flip and reposition wafers.
Typical transparent materials that watch or medical industries are concerned are mineral glass (for example, K1) and Sapphire. There are several challenges, among them – anti counterfeit marking. Required size and visibility of the marking defines type of laser and adequate positioning system. Nanosecond lasers allow economically viable writing in-glass marks visible with naked eye. Such inscriptions can be several centimeters in size for company logo in glass of the bottle, name of the owner of the item or matrix code. Anti counterfeit marking (whether company logo or matrix code) would be done with pico-second laser. Such images can be made easily visible or noticeable only with the aid of optical devices. Even more advanced images – result of refractive index modification- are done with femto-second lasers.
In industrial environment deep marking on steel is commonly done by photo lithography, mainly because of fine quality. It is efficient, but not flexible process, not convenient when content shall be changed. Photo lithography is replaceable by ultra-short pulse laser ablation. Some manufactures refrain from using laser process arguing that result is marred by burrs, however femto-second lasers completely eliminate the issue. Due to no heat affected zone, the scribed feature has sharp edges. Depth and flatness of the bottom can be regulated by changing beam focusing parameters. Even more, femto-second ablation can create micro grating which facilitates light interference and can be additional design feature.
For fast industrial processing ELAS has developed automatic laser focusing and automatic image recognition functionalities as well as CAD file import. Image recognitions function locates object based special marks or after scanning and matching scan result with image in memory. Precision of positioning is 5µm or better and depends on optics and positioning system. Each object is processed (marked, cut, etc) in the unique way according to related CAD file.
In recent years technological and economical benefits of flexible laser micromachining become more apparent. Industries adopt laser processing to replace mechanical and chemical techniques. Besides that, ultra-short pulse lasers offer new possibilities for designers and technologists. For them ELAS offers unique possibility to test ideas on newly built micro machining system with six positioning axes, helical drilling, pico-second and femto-second lasers, advanced software and vision systems.