Abstract: An infrared detector element includes a metallic patch which is positioned on the surface of an upper contact layer. A multiple quantum well ("MQW") infrared sensitive structure is positioned between the first contact layer and a second contact layer. The conductive contact layers are transparent to infrared radiation. A groundplane which is reflective to infrared radiation is positioned adjacent the second contact layer. A resonant cavity is formed between the metallic patch and the groundplane. The thickness of this cavity is not greater than approximately one eighth of the wavelength of the incident infrared radiation within the cavity. The metallic patch functions to couple the incident infrared radiation into the resonant cavity wherein the E-field is oriented substantially normal to the plane of the MQW structure. A plurality of the detector elements can be used to form a single pixel and an array of the pixels can be used to form a complete infrared radiation imager.