The FUJINON 2/3" HF-XA-5M series is designed specifically for cameras with 3.45µm pixels or larger. The "4DHR" means that it holds its resolution regardless of working distance and H and V. The lens gets its 5MP from being designed for the IMX250 high performance CMOS image sensor (2/3", 5 megapixels, 3.45µm pixel pitch) and of course is compatible with 2/3" Sony Pregius IMX sensors with pixels as small as 3.45µm.