Optical pathway

Listemick R, Louis DN, Packer RJ, Gutmann DH (1997) Optic pathway ghomas in children with neurofibromatosis 1 consensus statement from the NEl Optic Pathway Ghoma Task Force. Ann Neurol 41 143-149... 

There are also several proposals to use anodic aluminum oxides in producing optoelectronic devices. Porous oxides may find use as antireflecting coatings for optical pathways. Anodic alumina films doped by Eu and Tb are promising for application in electroluminescent cells for TEELs.28... 

Table 5.1 summarises the different research activities to improve the lateral resolution of LAPS. It is clearly demonstrated that the resolution can be extended down to the sub-micron range in the near future. This will broaden the possible application fields of the LAPS principle. For example, biological and chemical sensor arrays will benefit from further investigations and improvements of the lateral resolution of the LAPS. However, the LAPS works with an external light source, i.e., the experimentally applied light source, and its optical pathway will also limit the achievable resolution. 

The FAMOS initiative, introduced above, presented a flow cell (Figure 4.75) for optical inspections connected to one of the micro structured reactors in their new micro reaction system [124], The flow cell measures only a few cubic centimeters and the actual optical interface to a spectrometer consists of a macro-scale table-top device with a clamping mechanism which positions the flow cell in the optical pathway. 

Fig. 1. Optical pathway of (a) a compound microscope and (b) a phase-contrast microscope.

The function of the eye is to produce a clear image of the external world and to transmit this to the visual cortex of the brain. In order to do this the eye must have constant dimensions, an unclouded optical pathway and the ability to focus light on the retina. These requirements and the need for protection of the globe determine the special structure of the eye and its associated apparatus. 

The AR coating can provide transmission enhancements by reducing secondary surface reflections at glass interfaces. This improvement can be realized by up to a 7% increase in filter throughput (3). AR coatings on emission filters and dichroic mirrors also reduce the ghost image sometimes seen in optical pathways with multiple reflective surfaces. 

Electrochemical devices have proven very useful for sequence-specific biosensing of DNA. Electrochemical detection of DNA hybridization usually involves monitoring a current response under controlled potential conditions. The hybridization event is commonly detected via the increased current signal of a redox indicator (that recognizes the DNA duplex) or from other hybridization-induced changes in electrochemical parameters (e.g., conductivity or capacitance). Modern electrical DNA hybridization biosensors and bioassays offer remarkable sensitivity, compatibility with modern microfabrication technologies, inherent miniaturization, low cost (disposability), minimal power requirements, and independence of sample turbidity or optical pathway. Such devices are thus extremely attractive for obtaining the sequence-specific information in a simpler, faster, and cheaper manner, compared to traditional hybridization assays. 

Hero of Alexandria 125 BC Linearity of a light beam and the principle of fastest optical pathway Von Laue (1958)... 

Fig. 3. Exploded view of the thin film spectroscopy apparatus, showing the relative positions of the optical cooling surface, the interferometer, the optical pathway for measurement and the material source for the film. W, window (polished quartz or sapphire), O, ground surface onto which windows are glued, LED, light emitting diode, PD, photodiode...

Liquid Xenon is a low-temperature solvent for the temperature range between -112 °C mp, p bar) and 17 °C scp,p 60 bar). The greatest advantage of this unusual solvent is its complete transparency over the IR spectral range. The limited solubility of substances in liquid xenon is often compensated by a longer optical pathway of the cell [1]. Because of the inertness of LXe and the weak interactions between LXe and the dissolved species the method allows a kind of "low temperature gas phase spectroscopy". 

A particular property of mammalian IgG is that their absorbance at 278 nm is about 2.5-3.0 higher than at 251 nm, in contrast to other serum proteins where this ratio is about 1-1.5 (in neutral buffers). Measurements at these two wavelengths may, therefore, indicate the fractions which contain IgG and their approximate degree of purity. The actual A2nl 42n ratio may vary for individual antibody clones. At the same time, the absorbance at 278 nm is an indication of the IgG concentration if the optical pathway is 1 cm, a 1% solution (10 mg/ml) has an absorbance of 13.5+ 10% (Little and Donahue, 1967). 

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