In this paper, a new single-shot line sensor based on Fourier-domain spectral interferometry is presented. Each point of the sampled line is encoded by a different wavelength obtained by a chromatic dispersion at a grating. The requested height profile of the line is determined by combining a phase detection algorithm with an appropriate model-based approach. The robustness of this algorithm with respect to errors in the initial condition is analyzed before the final presentation of a measurement result.

Measurement of surface shape of diffusely reflecting objects by phase shifting digital holography is described. After basic principles and an experimental result are briefly explained, a digital simulation algorithm is presented that delivers 2-dimensional distributions of the reconstructed images and contours for general object and hologram recording conditions.

We have developed a non-contact surface sensing probe for a nano-coordiante measuring system. This micro-probe is controlled by optical radiation pressure. The probe sphere is oscillated and then damped near the surface by a viscouse drag force. The damping nature of the probe was studied to improve the precision of the surface detection. An attempt was made to characterize the probe damping nature by the viscous drag coefficient.

A new sensor will be presented, being capable to realize optical and tactile 3D measurements on workpieces by combining several measuring principles in one sensor head.
An image processing sensor enables lateral measurements of edges and margins of objects. To determine the objects surface shape, a laser distance sensor and alternatively a focus variation sensor, both operating thru the same telecentric optic, are used for vertical measurements. A third measuring method is realized by detachably mounting a flexible fiber including a tiny probing sphere in front of the optic to enable tactile probing (Figure 2a). As the deflection of the probing sphere has to be transmitted to a detection circuit via the stylus, all conventional tactile touch probes suffer from the limitations to the stylus diameter. Bending of the stylus does not have to be considered by using image processing for the direct determination of the probing spheres deflection. Existing commercially available fiber probe sensors are using this advantage for the lateral deflection with image processing (Figure 2b).
The vertical position of the probing element is defined by the vertical position of the coordinate measuring machine that is used for the probing process as the stylus element is vertically stiffen. Probing spheres are available down to 20 µm in diameter.
A new approach for the vertical deflection determination uses a laser distance sensor operating on the upper fiber end (Figure 4c). Lateral and vertical measurement are now combined to determine the three dimensional deflection of the fiber resulting from object contact. Image processing and distance sensing are provided by the same optical system applied above the fiber (Figure 4a). The vertical deflection of the fiber is enabled by a flexible stylus fixation that additionally ensures isotropic probing forces.
The new assembly will be presented as well as the current state of development. The target parameter for 1D probing error is below 0.15 µm using unidirectional probing. The specification for the 3D probing error is below 0.25 µm. It will be shown, how these values have been reached using special correction and calibration methods.

Nowadays the honing process of cylinder liners for combustion engines is monitored by 2D tactile measurements of the honing structure. The problem of tactile measuring is the required offline measurement of the cylinderblocks, which results in increased handling efforts and costs. In this paper a method is introduced which overcomes this disadvantage by applying an inline optical measuring system for 100% in line measurement of the honed cylinder liner surfaces. Focus is the comparison of two optical sensors, working after the principle of chromatic aberration and a fiber based white-light interferometer.