Selective glass surface modification with picosecond laser pulses for spatially resolved gloss reduction

Today, gloss and other properties describing the reflectance of a surface are important in a wide range of applications, e.g., for displays of mobile phones and laptops. Influencing the visual appearance and therewith the quality of an object, an inadequate gloss can lead to rejection of an item. Hence, these properties have to be precisely adapted to each application. Specifically, gloss reduction of spatially limited areas is quite challenging using common techniques such as chemical etching: Etch masks are required to prohibit the modification of the surrounding surface. This is sophisticated, expensive, and comparatively inflexible. Unlike with mask based processes, laser micromachining results in a very flexible tool for the modification of optical properties of selected surface areas. Furthermore, by using ultrashort laser pulses, the surface structuring is precise; it causes minimal thermal damage outside the micromachined area and shows a maximum degree of flexibility in terms of the geometry of t...