Micro-telescope

V.T. stretch, extend. — v.i. move. — aus-gezogen, p.a. extracted, etc. (of a line) solid (not broken or dotted), continuous. Aosaeh rohr, n., >rohret /. telescopic tube. tisch, m. extension table. -tubus, m. (Micros.) drawtube. -tusch, m., -tusche, /. drawing ink. 

Micro-Opto-Electro-Mechanical Systems (MOEMS) will be widely integrated in new astronomical instruments for future Extremely Large Telescopes, as well as for existing lOm-class telescopes. The two major applications are programmable slit masks for Multi-Object Spectroscopy (see Ch. 12) and deformable mirrors for Adaptive Optics systems. Eirst prototypes have shown their capabilities. However, big efforts have stiU to be done in order to reach the requirements and to realize reliable devices. 

A strong collaboration between micro-optics and astronomy will certainly lead to reach the best scientific return for the lowest cost in next generation astronomical instrumentation for ground-based and space telescopes. 

Rotation Modulation Collimators (RMC s) were originally introduced in X-ray astronomy to provide accurate source localizations over extended fields. This role has since been taken over by the grazing incidence telescope systems. The potential of the RMC s as wide field monitors have recently been demonstrated by the WATCH instruments on GRAN AT and EURECA. It now appears likely, that for use on large, 3-axis stabilized spacecraft, a pinhole camera system may provide better sensitivity than an RMC-system of corresponding physical dimensions. But due to its simplicity, low data rate, and ability to work on spin stabilized (micro)satellites, the RMC wide field monitor may still have a role to play in the X-ray astronomy of the future. 

Optical micrographs of cross sections of the extruded HDPE/iPP (25/75) filaments show a fine morphological structure with micro-spherulites aligned along telescopic rings (Fig. 11). In the decentralized centre of the filament there is a zone of almost circular shape with different morphology this region contains mainly HDPE. 

The concept behind optical devices which incorporate liquids as a fundamental part of the optical structure can be traced at least as far back as the eighteenth century where rotating pools of mercury were proposed as a simple technique to create smooth spherical mirrors for use in reflecting telescopes. Modem microfluidics has enabled the development of a present-day equivalent of such devices, the development of which we now refer to as optofluidics. As will be described below, the capabilities in terms of fluidic control, mixing, miniaturization, and optical property tuning afforded by micro-, nano-, and electro-fluidics combined with soft lithography-based fabrication provide an ideal platform upon which to build such devices. 

The diameter for the uncollimated laser beam was approximately 0.5 cm at the sample or 0.2 cm interrogation volume in the glass vial used. A laser power at sample of 500 mW (max) was used to excite the Remote Raman spectra in the sample. This resulted in a power density value of approximately 2.5 W/cm. In contrast, typical Micro Raman SERS experiments used power densities in the order of 20,000 W/cm to excite the Raman Shift spectra of samples contained in capillary tubes with an interrogation volume of 5x10 cm. This represents 8,000-fold increase in energy density for the microscope experiments than the telescope based Raman experiments. 

The mechanics of the pull-out of a strand was studied by special techniques to evaluate individual filaments within the strand. Zhu and Bartos [37] used for that purpose a micro-push off technique, which was used to load individual filaments in the strand and determine their resistance. Banholzer and Brameshuber [32-34] developed a novel test in which pull-out loading and imaging of the individual filaments could be carried out simultaneously, to observe the filaments which were fractured during the test. Both studies confirmed earlier reports (for more details see Sections 8.4 and 8.5) of a sleeve-core failure mechanism, where the external filaments (sleeve), which are better bonded to the matrix, tend to fracture, while the internal ones (core), undergo pull-out (Figure 13.8), in a mode which was described by Bartos [38] as a telescopic mode of pull-out. Banholzer and Brameshuber [32-34] demonstrated the parallel trend between the pull-out resistance and the number of filaments which remain active (i.e. the non-fractured filaments) as a... 

---