2D and 3D Inspection for Smartphone Components
The visual impression, the haptics of the first touch and an intuitive functionality are the most decisive factors for consumers when choosing a smartphone. While functionality is determined by the pre-defined selection of components as well as the smartphone software, the visual impression and the haptics are not only depending on design but, above all, on the manufacturing quality of the device and its components. This means an exact match of form and geometry with respect to the design and an accurate and precise compliance with process tolerances. Even a few micrometres deviation from the specifications lead to a changed and less valuable visual impression as the human eye is able to recognize smallest misfits.
Also, user experience will be influenced by manufacturing quality as the form-fit of the individual parts are a prerequisite for tightness and splash water protection. Moreover, product safety and longevity are a competitive factor for smartphones of all price categories. To prevent dangerous pressure being exerted on the built-in batteries individual components must match exactly. Solarius has developed automated in-line metrology systems that use optical 3D measurement technology to provide manufacturing process control and to assure compliance with specifications and tolerances. The measurements are performed without user influence at highest cycle times to guarantee a 100% inspection for largest quantities.
Display and Body Fitting
The exact position of a smartphones front cover glass in relation to the backside cover, mainly manufactured of metal, plastics or glass, prevents disturbing edges, gaps and offsets. 3-dimensional glass surfaces side by side with metallic parts require high dynamic measuring technology mastered by chromatic-confocal sensors and intelligent object handling capabilities as provided by the OMT.
Smartphones regularly become built in two half shell assemblies, carrying the mechanical and electronical components, before they become combined to the fi nal product. During the combination of the half shells the battery becomes packed in between. Only if there is exact clearance between the top and bottom assembly of the proper fit of the battery can be ensured. Pressure, exerted on the battery is critical for product safety as current battery technologies are sensitive to pointed forces and bending. Air gaps are unwanted with respect to product value recognition. For this purpose, each pair of shell assemblies gets checked by a laser triangulation system immediately before the final assembly. Any mismatching parts are sorted out reliably.
Battery Pack
The battery is one of the most important components of every smartphone, making maximum use of the available installation space. Compliance with the size specifi cations is important in order to avoid pressure on the battery, which can lead to defects. The Solarius automated measurement tool for battery packs (AMT) measures width, length, thickness, flatness and the reaction to pressure fully automatically and without user infl uence with a cycle time of just four seconds, sorting out any defective parts.
Ink Measurement
A defined amount of black ink is applied to ensure a clean termination of the backlight and a firm fit of the cover glass. This is done in steps to ensure that the ink runs perfectly straight when pressing on the cover glass. The black ink in combination with glass requires remarkably high sensor dynamics, which is provided by the IMT (Ink Measurement Tool) from Solarius. The average and maximum height of each individual step is determined and defects are detected in a minimum of time.
