Spot scanning

These structures were recorded by a vectorial focal spot scanning in a spiral-by-spiral method rather in a raster layer-by-layer mode using a PZT stage. Such spiral structures fabricated in SU-8 have optical spot bands in near-lR [24], telecommunication [25], and 2-5 pm-IR region [26] or can be used as templates for Si infiltration [11]. It is obvious, that direct laser scanning is well suited for defect introduction into 3D PhC, as demonstrated in resin where a missing rod of a logpUe structure resulted in the appearance of a cavity mode in an optical transmission spectriun [27]. 

From XRD line widths, it was noted that the crystal size increased as the S concentration increased, although values were not given. A simple but useful characterization technique to quantify film thickness homogeneity was used here. The transmittance of a focused light spot scanned across the sample showed excellent homogeneity. 

Data enrichment currently only deals with host information and vulnerability assessment information, although additional sources are under investigation, such as the Cisco Threat Response (CTR) technology1 that provides on-the-spot scan ability for IDS alert assessment. Both functions are presented in greater detail in Section 5. 

Furmidge, G.G.L. The application of flying-spot scanning to particle size analysis in the formulation of pesticides. Analyst. 1963, 88, 686. 

Zhou, Z. H., Prasad, B. V. V., Jakana, J., Rixon, F. J., and Chiu, W. (1994). Protein subunit structures in the herpes simplex virus A-capsid determined from 400kV spot-scan electron cryomicroscopy./. Mol. Biol. 242, 456-469. 

P-15 ZnO Ztfi blue- green very short (2.8 us) flying spot scan... 

Another possibility is to use a fibre bundle. The input side of the bundle is made circular, the out side is flattened to match the polyehromator slit. The large area of the fibre bundle makes it relatively simple to collect the light from the nondescanned detection path of a scanning microscope. However, the aperture of the microscope objective lens must be correctly imaged onto the input of the bundle. Otherwise the illuminated spot scans over the bundle and causes the fibre structure to appear in the image. 

Soft X-ray transmission scanning microscope Scanning transmission X-ray microscopes (STXRM) for soft X-rays use Fresnel zone plates as high-resolution objectives to form a focused spot. Scanning microscopes require coherent illumination and are... 

Next, 2 il of the sample and standard solution (100 g/ml methanol) are spotted onto a silica gel 60 plate with preconcentration zone (Merck), developed with 1 -butanol/water/acetic acid (6 2 2) over 6 cm, air-dried, sprayed with xanthydrol reagent (15 mg xanthydrol + 9 ml hydrochloric acid + 0.75 ml acetic acid), heated for 5 min at 110°C, and the purple spots scanned at 525 nm. The / y values obtained by this method were... 

Most studies in TLC have been qualitative, and considerable experimentation may be necessary to obtain quantitative results, although excellent commercial layers and new equipment have aided the problem. Phenolic compounds have been analyzed by spectrophotometry off the plate at 725 nm (133) by means of Folin-Ciocalteu reagent, essentially sodium tungstate and molybdate with lithium sulfate (134). Chlorophenols have been quantified after reaction with dansyl chloride and separation (135). Channel TLC (linear relationships between spot lengths and concentration between 1 and 8 pg/spot) has been used (136). The phenols in cashew nut shell liquid have been quantified by off and on the plate methods with a flying-spot scanning procedure and densitometry (137) and the distribution of unsaturateds by TLC/MS (138). Catecholamines and their metabolites in urine have been quantified (12) and determined by on the plate fluorimetry (139). Hindered phenols have been analyzed by densitometry (140). Semiquantitative determinations of the coupling products of 4,4 -... 

TEM has two basic modes, one is conventional transmission electron microscopy (CTEM or TEM for short) mode using a broad beam, another one is scanning TEM (STEM for short) using a focused electron probe (by focusing the electron beam into a narrow spot) scanning across TEM specimen in a raster. 

Uniformity of Response For some applications, it will matter whether the detector responsivity is uniform over its surface or whether some parts are more sensitive than others. Actually, no detector is perfectly uniform, so the question really is how nonuniform it is, and how much nonuniformity the customer can tolerate. In theory, a response profile (sometimes called a spot-scan- a plot of responsivity vs. position) is a good way to report uniformity. This may be possible with some single-element detectors, but for most modern detectors the sensitive surface is so small that we cannot obtain an optical spot small enough to measure the response uniformity. Instead, we revert to the determination of MTF. 

We mention spot-scans for completeness and as an introduction to MTF, but they are not nearly as important now as they were in the 1960s. At that time many detectors were many millimeters in size - considerably larger than available spot sizes - so we could measure responsivity at many points across the detector, and plot responsivity versus position. Nonuniformities were often seen near the electrical contacts, for example. The size of most modern detectors is comparable, or smaller than, the smallest spots available. The theory described here still applies, but in practice it is not relevant. 

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