Teledyne Brown Engineering has developed a low-cost infrared seeker (LCIRS) for manportable terminal homing rounds. In order to minimize production costs, the development emphasized design simplicity and inexpensive manufacturing processes. LCIRS engagement parameters represent a short-range round launched over a land combat vehicle. The seeker optical system has an aerodynamically spun dome that holds a roof mirror on the inside cylindrical axis. This provides a rotary field scan for a strapdown primary aspheric mirror and detector array. The two-color thermoelectrically cooled array uses lead sulfide and lead selenide detector elements. A coated germanium anti-solar spectral filter with a passband that cuts on at 2.3 μm is employed. Replicated optics were used to minimize costs. Considerable attention was devoted to the design of signal processing electronics for the LCIRS. Multichannel preamplifiers were employed. Complete signal processing electronics were developed, fabricated, and tested. Design requirements, design parameters, optical system characteristics, and system performance are presented.