The Application segment delineates the end‑use environments that drive demand for NaI(Tl) Scintillation Crystal. Medical imaging—including gamma cameras, SPECT systems, and PET scanners—remains the largest contributor, accounting for roughly 45 % of total market revenue due to its extensive use in diagnostic radiology and oncology. Homeland security applications, such as portal monitors, radiation detection portals, and cargo scanning equipment, represent about 30 % of the market, reflecting heightened regulatory focus on illicit radioactive material detection. Nuclear research—encompassing particle accelerators, neutron detection, and radiation monitoring laboratories—contributes approximately 15 %, supported by ongoing scientific investigations and decommissioning projects. Finally, oil & gas exploration uses NaI(Tl) crystals for downhole logging and well‑site radiation surveys, comprising the remaining 10 % of sales. Collectively, these sub‑categories form the core of NaI(Tl) Scintillation Crystal segmentation, each adding distinct revenue streams that shape overall market size.