The 62A11-02-020S is a 1/2" package optical rotary encoder manufactured by Grayhill, featuring a 22.5° detent angle with 16 positions and an integrated pushbutton switch. It operates at 5.0 Vdc with a 2-bit quadrature coded output, compatible with CMOS, TTL, and HCMOS logic. The encoder utilizes optical coupling with a gallium aluminum arsenide infrared emitter and planar silicon NPN phototransistor, rated for over 1,000,000 rotational cycles and 3,000,000 pushbutton actuations. Key specifications include a supply current of 30 mA maximum, operating torque of 2.0 ±1.4 in-oz initially, and contact resistance less than 10 ohms. This encoder is ideal for applications in global positioning systems, driver information systems, and medical equipment where reliable rotational position sensing and user input are required.