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Quantitative deflectometry is a new tool to measure specular surfaces. The spectrum of measurable surfaces ranges from flat to freeform surfaces with steep slopes, with a size ranging from millimeters to several meters. We illustrate this by several applications: eye glass measurements, measurements of big mirrors, and in-line measurements in ultra-precision manufacturing without unclamping of the sample. We describe important properties of deflectometry and compare its potentials and limitations with interferometry. We discuss which method is superior for which application and how the potential of deflectometry may be developing in the future.

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We introduce a novel concept for motion robust optical 3D sensing. The concept is based on multiline triangulation. The aim is to evaluate a large number of projected lines (high data density), in a large measurement volume, with high precision. Implementing all those attributes at the same time principally allows for the "perfect" single-shot 3D movie camera (our long-term goal). The key problem toward this goal is ambiguous line indexing: we will demonstrate that the necessary information for unique line indexing can be acquired by two synchronized cameras and a back projection scheme. The introduced concept preserves high lateral resolution, since the lines are as narrow as the sampling theorem allows. No spatial bandwidth is consumed by encoding of the lines. In principle, the distance uncertainty is only limited by shot noise and coherent noise. The concept can be also advantageously implemented as a hand-guided sensor with real-time registration, for a complete and dense 3D acquisition of complicated scenes.

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In spoken language, local acoustic information is frequently consistent with more than one phoneme. This study investigates the influence of acoustic and semantic information on phoneme categorization as a sentence unfolds in time. Ten target stimuli forming a Goat-to-Coat continuum were created from natural speech by manipulating the voice onset time of the initial consonant. These stimuli were embedded in biased sentences such as: Goat-biased: The busy dairyman forgot to milk the (Goat/Coat) in the drafty barn. Coat-biased: The careful tailor hurried to press the (Goat/Coat) in the cluttered attic. A cross-modal interference task showed immediate effects of acoustic information; effects of semantic information appeared 450 ms later. A cross-modal identification task showed immediate sentence context effects for ambiguous mid-range stimuli while identifications 450 ms later showed context effects for endpoint stimuli. A word monitoring study showed immediate context effects throughout the acoustic parameter range. These data support an account of auditory sentence comprehension in which semantic information does not immediately and automatically influence phonological analysis of an acoustic signal; contextual influences occur over time or when a task or situation requires explicit judgment about the identity of a stimulus. [Work supported by NIMH, Grant No. MH42900, and NIH, Grant No. DC00494.]

We will discuss deflectometry from the physicist's and from the information theoretical point of view. The intrinsic features of deflectometry-incoherence, source encoding, high dynamical range, simplicity, and scalability-enable new sensors and unexpected applications. We will demonstrate that deflectometry is a novel imaging principle with a wide spectrum of new applications. The local slope of specularly reflecting surfaces can be measured for objects from µm-size to meter-size. With simple means, it is possible to find shallow (nm-) grooves or defects and to generate SEM-like images with high dynamical range. Microdeflectometry in transmission supplies extremely sensitive quantitative "phase contrast". Macroscopic deflectometry in transmission allows us to measure local refractive power with an accuracy better than 1 mD.