14 research outputs found

    Application of smoothing techniques to relief-type resist surfaces generated by direct write electron-beam lithography

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    Complex relief-type resist surfaces are of increasing interest for applications in optical and photonic devices. They can be fabricated by using direct write electron beam lithography. The crucial point in the fabrication of such reliefs is the inexact approach to the desired resist profile and the increased roughness of the resist surface. This work focuses on three important steps towards a better realization of smooth profiles, i.e. an improvement in beam position accuracy, a reduction of exposure errors caused by the insufficiency of the conversion software and a smoothing technique applied after development. The introduced techniques are expected to considerably improve the functionality of relief type devices

    The neural circuitry involved in the reading of German words and pseudowords: A PET study

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    Contains fulltext : 14184-OA.pdf (publisher's version ) (Open Access)Silent reading and reading aloud of German words and pseudowords were used in a PET study using (15O) butanol to examine the neural correlates of reading and of the phonological conversion of legal letter strings, with or without meaning. The results of 11 healthy, right-handed volunteers in the age range of 25 to 30 years showed activation of the lingual gyri during silent reading in comparison with viewing a fixation cross. Comparisons between the reading of words and pseudo-words suggest the involvement of the middle temporal gyri in retrieving both the phonological and semantic code for words. The reading of pseudowords activates the left inferior frontal gyrus, including the ventral part of Broca's area, to a larger extent than the reading of words. This suggests that this area might be involved in the sublexical conversion of orthographic input strings into phonological output codes. (Pre)motor areas were found to be activated during both silent reading and reading aloud. On the basis of the obtained activation patterns, it is hypothesized that the articulation of high-frequency syllables requires the retrieval of their concomitant articulatory gestures from the SMA and that the articulation of low-frequency syllables recruits the left medial premotor cortex

    Multi-wavelength optical pickup with diffractive optical elements

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    A novel, to our knowledge, multi-wavelength diffractive optical pickup is presented. The pickup enables multi-focus imaging and increases the data transfer rate considerably. Parallel reading of two or more memory layers is possible. The different spots can be controlled independently. The optical pickup consists of different diffractive optical elements (DOEs). The measured full-width at half-maximum (FWHM) spot intensity for the DOE-pickup is 0.76 mu m-close to the diffraction limited predicted value of 0.71 mu m-indicating good optical performance. The measured highest diffraction efficiencies of the realized DOEs are about 92%

    Effect of drawing hand and age on figural fluency : a graphomotor study with the five-point test in children

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    The aim of the study was to assess conceptual thinking in children in relation to age and motor dominance. We investigated the effect of the right and the left hand in a fluency task in four groups of 127 healthy right-handed children (age 5-12 years) and an adult control group. They performed the Five-Point Test twice, once with their dominant right and once with their nondominant left hand. The number of items and errors were analyzed with respect to age, drawing hand, and motor transfer. The performance of boys and girls did not differ. There was a significant effect for age and a prominent interaction between age, hand, and order (right hand or left hand first). Performance improved linearly with age. The dominant right hand performed generally better and there was a learning effect for both hands, but there was a learning advantage for the dominant hand, which increased with age. The influence of motor dominance in this fluency task seems to establish before conceptual maturity (around age 7, respectively 9 to 10)
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