PIN-bridge distance measurement sensor

The presented integrated optical distance measurement sensor works on the time-of-flight principle. The distance information is obtained from the correlation of received light and the transmitted signal. The PIN-bridge circuit concept ensures suppression of background light by equally charging and discharging a capacitor within one period, while integrating the wanted signal. A single distance measurement is performed in 8 ms. With averaging, an accuracy of better than 1% is achieved for a distance of 3.7 m. Effective pixel size is 150×200 μm² having a fill-factor of ∼10%. The sensor was manufactured in a modified standard 0.6 μm BiCMOS process.