MEMS-based optoelectronic system for distance measurement applicable for panorama cameras

Abstract

Photogrammetric imaging and measurement techniques are widely used for capturing three-dimensional scenes in sciences and arts. Traditional approaches performing extensive calculations on multiple images are more and more replaced by higher integrated and faster operating measurement devices. This paper presents a MEMS-based system for distance measurement that can be integrated into a commercially available panorama camera and will add three-dimensional measuring capabilities. This combination is very suitable to displace the current procedural manner using different instruments to acquire three-dimensional data on the one hand and texture on the other hand. The data acquisition is simplified and extensive calibration and data transformations is no longer needed. Thereby the accurate allocation between texture and distance data is firmed by design. This work outlines the optical concept to couple both measuring systems into one optical path. While texture is captured line wise, the distance is acquired sequentially. Integration of both functionalities into one housing and one optical system design requires miniaturized components for deflection of the measurement beam. One solution is to use a resonant MEMS scanning mirror. The paper describes the resulting optical setup in detail. The integrated construction principle induces special requirements for the LIDAR distance measuring method used here. In order to ensure eye safety, the measuring light beam is limited to low power signals. The contribution also will present an approach for processing low level signals and performing high measuring rates.