A method and apparatus to couple a personal communications device to an integrated vehicle interface is provided. The method involves taking a reflectance reading from one surface of an inert porous matrix impregnated with a reagent that will interact with the analyte to produce a light-absorbing reaction product when the fluid being analyzed is applied to another surface and migrates through the matrix to the surface being read. The patterning structure is configured to impart the beam of radiation with a pattern in its cross-section. The font height generator receives a predetermined font height reference value and the horizontal line number information, obtains automatic font height, and generates the automatic font height. A shaft supporting a press fitted gearwheel that exhibits a hub and a cog path connected to the hub, the hub exhibiting at least one flank extending axially outside the cog path whereby the hub exhibits a through-hole with a first area situated axially outside the cog path and a second area situated radially inside the cog path. Another aspect of the present invention involves a method of preparing a PEM-coated implantable medical device, comprising the step of applying a film to a surface of an implantable medical device, wherein said film comprises a polyelectrolyte multilayer and said surface is glass, metal, plastic, polymer, or fiberglass.