Biologically active films play a pivotal role in the realm of medical devices and sensors, where precision, reliability, and compatibility are paramount. These films, often composed of biomaterials or functional coatings, are integrated into a diverse array of applications, ranging from implantable medical devices to diagnostic sensors. The accurate measurement of film thickness is not merely a technical necessity; it is a fundamental requirement that directly influences the performance and safety of these critical biomedical tools.

For instance, in the development of implantable medical devices such as drug-eluting stents or bioresorbable scaffolds, the controlled deposition of biologically active coatings dictates their drug release kinetics and biocompatibility. In diagnostic sensors, the precise thickness of functional layers is essential for ensuring optimal sensing performance, sensitivity, and selectivity. Consequently, the characterization of these films extends far beyond