Lenses of the next generation for display manufacturing
Currently LEONI is working on the development of synthetic Fused Silica for rod or cylinder lenses of the next generation. These rod lenses are included in the so-called Line Beam Systems and are used in the manufacturing of flat screens, for example mobile phones or tablets.
Using high energy UV Lasers the semi-conductor layers included in the screens are modified into crystalline structures to make them usable for the application as thin film transistors. To do so a laser stream is converted into a long ‘line‘ (which scans the screen during production) using the large scale lens systems (rod lenses). Currently lenses with a length of 850 mm are utilized. Future generations of Line Beam Systems will require lenses with the length of 1.500 mm and more, hence considerably longer.
The figure shows the image of a polished rod. The length of the lens in the picture is 430 mm. The production of high purity Fused Silica for lenses of this size requires new and specially adjusted process steps in order to, among other things, being able to produce and process these large geometries and weights. To produce a suitable blank, a so called ingot, quartz production has to run 24 hours a day for 10 days without any interruption. LEONI’s wholly-owned affiliate j-plasma GmbH is one of the very few internationally qualified and licensed suppliers of this new technology.