Abstract: In response to the demand for low-power, small-size, lightweight, low-cost, high-performance, and fast-cooling cryogenic coolers for use with high-performance infrared detectors on light-load platforms such as hand-held thermal imagers and UAVs, Kunming Institute of Physics (K.I.P) has developed micro linear coolers for higher operating temperature (HOT) IR detectors. The linear resonant compressor was studied to operate at 100 Hz to increase power density. Simultaneously, a pneumatic expansion design incorporating a back pressure chamber was achieved. After multiple rounds of optimization and iterative design, the development of the C351 cooler was completed. Performance system tests verified the advancement of the indicators, and the cooler has reached small-batch production capacity. The performance of the matching 640×512 HOT medium-wave infrared detector includes power consumption of less than 2 W (thermal load 180 mW@77 K@23℃), cooling time of less than 90 s, and a cooler weight of 217 g (drive control circuit: 12 g).