Low Distortion C-Mount lens for up to 2/3" sensors such as IMX487

The CIL531 is an 8mm C-mount lens for 2/3" sensors up to 12MP with 2.2um pixel pitch. The IMX487, IMX546, and XGS5000 are all sensible matches. The iris adjusts from F/2.8 to F/16, and the 11mm image circle covers the full 2/3" format. This is a good middle-ground focal length when you need more width than a 12mm lens but less perspective exaggeration than very short focal lengths create.

The CIL531 measures -1.9% from rectilinear. That is fine for most machine vision work, including barcode reading, robotics guidance, and conveyor inspection. If you need sub-0.5% distortion for precision metrology, you should move to a longer focal length in the CIL53x series. The 69° field gives you useful coverage without turning the scene into a wide-angle compromise. You can verify coverage at field of view calculator

The lens uses an all-glass optical design in a compact C-mount barrel, and the full assembly weighs 62g. That weight is low enough for small camera housings and pan-tilt systems that cannot carry heavy glass. The front uses a 1"-32UNF-2A thread for standard C-mount filters. The focus range starts below 100mm, which helps when inspection space is tight.

The standard C-mount interface fits cameras from FLIR, Basler, Lucid Vision, Allied Vision, and similar industrial camera vendors. The 17.526mm flange focal distance is standardized, so the mechanical side stays simple. If you need a refresher on C-mount versus CS-mount, see lens mount guide

The CIL531 is available as CIL531-F2.8-CMANIR without an IR filter. All in-stock units ship the same day from San Diego when you order before 12 PM PST. Volume pricing, Trioptics MTF data, and STP files are available through our US-based engineering team.