An innovative technique for measuring both the shape, the displacement, the strain and the temperature fields at the surface of an object using a single stereovision sensor is proposed. The sensor is based on two off-the-shelf low-cost high-resolution uncooled CCD cameras. To allow both dimensional and thermal measurements, the sensor operates in the visible and near infrared (NIR) spectral band (0.7-1.1 µm), and a radiometric and geometric calibration of the sensor is required. This technique leads to a low-cost camera-based simplified instrumentation that gives simultaneously dimensional/kinematical and thermal field measurements.Key words: geometric camera calibration, radiometric camera calibration, shape measurements, strain measurements, temperature measurements, full-field measurements, stereovision, digital image correlation (DIC), stereo-correlation, 3-D metrology, experimental mechanics. Preprint submitted to Experimental MechanicsJune 2007 1 Introduction For temperature measurements, many sensors are also available, from the classical thermocouples up to more sophisticated non-contact sensors like infrared cameras or pyrometers [14,15]. Thus, getting the strains and temperature at the same time implies generally a multi-instrumentation of the set-up and it is not so easy to combine the measurements of various categories in order to get the strains and the temperature at a given point of the specimen surface. 2 classical thermocamera with the 3-D shape data provided by a stereovision sensor. Their technique requires three cameras (an IR camera and two CCD cameras for the stereovision sensor) and a specific calibration procedure is needed to perform the fusion of the thermal and kinematical data provided by two different types of cameras. Satzger et al. [17] propose to utilize an infrared camera with a fringe projection technique to obtain a cloud of 3-D points and

An ideal thermographic camera could be defined as an uncooled system with high spatial and thermal resolutions featuring a video frame rate, and a short calibration process. In this paper a measurement system based on Silicon FPA operating in the Near Infrared spectral band (0.7 − 1.1 µm) is proposed. This system offers an excellent spatial resolution, a low cost and compactness. With a specific radiometric model, this system can accurately measure temperatures, in a broad temperature range, from 400 up to 1000°C. A comparison with two commercial infrared cameras is performed between 400 and 700°C.

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