Engineering Perspectives on Medical Lasers: Gain-Medium Classification, Laser–Tissue Interaction, Dosimetry, Clinical Applications, and Future Intelligent Systems

Medical lasers are a heterogeneous class of interventional and therapeutic devices. They are differentiated based on their active gain medium, which includes solid-state, gaseous, dye, and semiconductor (diode) formulations. The present article undertakes a systematic evaluation and synthesis of the findings from a reproducible dataset. The present study yields novel scientific results, including a four-level classification of medical lasers that considers the chemical formula for each type of gain medium. In addition, a multisided systemic analysis of the engineering application of medical lasers in clinical practice is conducted, including an analysis of the main engineering challenges as a structured framework. Furthermore, a clustering of engineering applications for medical lasers in 2025 is performed, and a quantitative landscape of medical lasers by variables is presented. The following variables are analyzed: wavelength (nm), power (W)/irradiance (W/cm2), fluence (J/cm2), and exposure time/pulse duration. The objective is to create a year-by-year “trend analysis” for future engineering opportunities (2026–2030). The structure of the article is logical and roughly follows the IMRAD structure, and a thread of argumentation is demonstrated.