Novel and simply producible large-area focal plane infrared imaging device based on quantum wells

We propose a new concept for long wavelength infrared imaging using a pixelless up-conversion device together with a CCD camera. The concept is applicable to wavelengths longer than the CCD response range (longer than about 1.1 micrometer). We present experimental results which support the scheme for infrared imaging. Our first device consists of a long wavelength p-type GaAs/AlGaAs quantum well infrared photodetector (QWIP) on top of which is grown a shorter wavelength InGaAs/GaAs light emitting diode (LED). Upon long wavelength infrared excitation of the QWIP, near infrared light is generated by the LED whose output is directed towards a commercial CCD camera where the up-converted image of the long wavelength infrared source object is formed.