FL75mm F1.2 Long Wave Athermalized Infrared Lens for 384x288-17um Detector

The 75mm F/1.2 LWIR Athermal Lens is a long-focal-length infrared optic purpose-built for 384×288–17μm detectors, delivering a narrow 5°×3.8° field of view that excels at extreme long-range target identification, reconnaissance, and border surveillance applications. With an F/1.2 aperture and reliable transmission across the 8–12μm band, this lens captures sufficient thermal energy to resolve fine details at considerable distances, while its athermalized design ensures stable focus and consistent optical performance across the entire –40°C to +80°C operating range—eliminating the need for manual refocusing in harsh and thermally dynamic environments.

Weighing 262g with an M34×0.75-6g thread mount and a compact φ8.46mm barrel profile, this fixed-focus lens offers straightforward integration into long-range thermal observation systems, vehicle-mounted cameras, and fixed surveillance posts. The back working distance of 14.25mm and back focus length of 8.5mm facilitate precise optical alignment, while the lens withstands extreme storage conditions from –60°C to +80°C. Engineered for mission-critical deployments where every detail matters at distance, this lens delivers the reach, clarity, and thermal stability required for professional-grade long-wave infrared imaging.

75mm f#1.2 Infrared Athermal Lens Parameter