Laser scan micrometers

The laser scan micrometer is a high-precision laser measuring system that performs non-contact... 

Addition of modern measuring techniques using laser scan micrometer, co-ordinate and visual measuring systems. 

Figure 4. Confocal laser scanning microimages of compression film from formulation II. The organization of the biopolymers were resolved by confocal fluorescence (excitation 484 nm, emission 520-580 nm), the PEO was defined by confocal reflection (633 nm). The micrograph was collected in stereo projection in extended focus images of 20-30 micrometer-thick slabs of the film. Field width,...

The topic of ocular bioavailability of indomethacin administered in a sub-micrometer emulsion was al.so examined by the research group led by M, J. Alon.so at the University of Santiago de Compo-stela, Spain (32). These workers tested several carriers in vivo in rabbits nanopaiticles, nanocapsules, microparticles, and a submicrometer emulsion. The latter, prepared by the method of Yu et al. (33) with poloxamer 188 and soybean lecithin and containing 0.1% w/v indomethacin, had particles of diameter 0.21 0.02 im. The submicrometer systems (nanoparticles, nanocapsules, and emulsion) increased by more than three-fold the indomethacin concentration in the cornea, aqueous humor, and iris-ciliary body at 0.S and 1.0 h post instillation. Furthermore, an increased indomethacin bioavailability of 300% was observed in comparison with the value obtained for an aqueous commercial solution. Confocal laser scanning microscopy studies indicated (hat the submtcion particles penetrated into the comeal epithelium cells by endocyiosis (he audiors further suggested that the vehicle components (lecithin in the case of emulsions) may act as penetration enhancers or as endocytotic stimulators. 

Several kinds of microscopic methods which can construct a 3-D image of the solid sample have been developed. Depending on the spatial resolution obtained in the 2-D observation, the reliable size of pores and pore volumes vary to a large extent. Typically, the finest resolution is a few micrometers for X-ray tomography, a few hundred nanometers for laser scanning confocal microscope (LSCM), and below 10 nm for high resolution... 

STXM permits to investigate the rearrangement of nanometer sized colloids. These measurements turned out to be quiet time-consuming and we did not achieve quantitative information on the reorganisation dynamics of single colloids. This is possible by laser scanning confocal microscopy. However, therefore micrometer-sized... 

Figure 1 shows the spatial resolution of various types of microscopy and scattering methods, including 3D microscopy techniques such as laser scanning confocal microscopy (LSCM), X-ray computerized tomography (X-ray CT), and TEMT. LSCM has been extensively used to investigate the phase-separated bicontinuous structures of polymer blends. It should be noted that X-ray CT is particularly useful for opaque specimens with micrometer-sized stmctures, while transparent specimens are necessary for LSCM. X-ray CT has been also extensively used in medical sdence. In the early 1990s, the spatial resolution of X-ray CT was limited to ca. 100 im. Recently, the resolution has substantially improved and is now comparable with ( 1 pm) or even superior to that of optical microscopy. 

Micrometer and atomic (nm) resolution can be obtained in the study of semiconductors in their function as electrodes. The two most prominent techniques used at the end of the century were scanning laser spot (SCS) and scanning tunneling microscopy. 

Direct visualization of nano- and micrometer-sized objects is the most straightforward way for their analysis in surface and polymer science, biomaterial research, and biology. Rapid progress in engineering and microtechnology has led to numerous techniques that allow observation and mechanical manipulation of microscopic objects of various natures. AFM [52] is the most commonly used of these techniques. In AFM, a sample surface is mechanically scanned with a tiny probe—a sharpened stylus fixed at the end of a flexible cantilever. When the stylus interacts with the samples, the resulting force acts on the stylus and causes deflection of the cantilever. This deflection is detected via an optical lever system, that is, a laser beam reflected from the end of the... 

Traditional measurements reported by various investigators have been made on extrudates either with a micrometer or by weight per unit length. The Monsanto Industrial Chemicals Co. (Akron, OH) has introduced an automated capillary rheometer (the Monsanto Processability Tester) which employs an extrudate swell detector based on interaction with a scanning laser beam positioned immediately below the capillary die exit. This enables measurement of the running die swell. 

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