The FCT3065‑XY Optical Mouse Sensor is a PixArt-branded optical motion sensor commonly found in budget and mid-range computer mice. It serves as the core tracking component that detects movement across X and Y axes by optically capturing surface motion and translating it into cursor movement. Specific performance details like maximum resolution, CPI/DPI range, and frame rate aren’t widely published, but community reports suggest typical implementations track movement into the lower-to-mid DPI range (e.g., around 800–2000 CPI). The sensor interfaces via low-speed digital protocols and is popular among OEM mouse designs where cost-efficiency is prioritized over high-end gaming performance.