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A novel quantum effect photodetector array consisted of AlAs/GaAs/InGaAs/GaAs/InAs/ quantum-dots in quantum-well hybrid structure has been tested. It showed a wide response wavelength range from 400nm to 1000nm. The low threshold voltage (−0.8V) and the high responsibility (10A/W) at 77K made it a good choice for optical detection. A custom-made capacitor feedback transimpendance amplifier (CTIA) readout circuit has been designed and processed to readout photoelectric conversion signals. The readout linearity was better than 99.5% by experiment. The signal to noise ratio and the monochrome voltage responsibility reached about 67dB and 10 A/W respectively when the photodetector was biased −1.0V and irradiated under a 633nm laser. A data acquisition accompanied by a display system has also been designed and presented at last to verify the application prospect of this novel photodetector. In view of the different photo-response of each detector in the photo array, we analyzed the non- uniformity correction (NUC) method, and a method of two-point multi-section correction is presented. [ABSTRACT FROM PUBLISHER]

The novel acoustic analog front-end receiver chip basing all-CMOS technology was designed to amplify the weak signal depressed the harmonic distortion and interference of adjacent channels for multi-channel acoustic imaging system. The 48 channel variable gain amplifiers (VGA) with the exponential gain control, multi-channel output data strobe, output buffer and continuous-time and anti-aliasing fourth-order Butterworth low pass filter for high signal-noise-ration (SNR) of analog-to-digital convertor (ADC), and integrated a vertical shift register. By the simulation verification, processing and test, the system shown linearity gain dynamic range 52dB, the equivalent input noise 5.2nV /Hz1/2@ 1.5MHz, and - 3dB bandwidth on 15MHz~92MHz. When the gain was less than 55dB, the second-order harmonic distortion was less than - 40dB, the receiving sensitivity 50µV while signal to noise ration (SNR) 30dB, the power consumption of each channel 6mW at 5V power supply. [ABSTRACT FROM PUBLISHER]