Ultraviolet optical materials used

The optical transmittance properties of materials used in the ultraviolet through to the infrared are shown in Figure 1. A similar transmittance plot for optical materials used in the infrared is shown in Figure 2. However, optical properties are only one of the factors to be considered, particularly in the... 

The compounds K5Nb3OFi8 and Rb5Nb3OFi8 display promising properties for their application in electronics and optics. The compounds can be used as piezoelectric and pyroelectric elements due to sufficient piezo- and pyroelectric coefficients coupled with very low dielectric permittivity. In addition, the materials can successfully be applied in optic and optoelectronic systems due to their wide transparency range. High transparency in the ultraviolet region enables use of the materials as multipliers of laser radiation frequencies up to the second, and even fourth optical harmonic generation. 

The main region of interest for analytical purposes is from 2.5 to 25 fim (micrometres), i.e. 4000 to 400 wavenumbers (waves per centimetre, cm-1). Normal optical materials such as glass or quartz absorb strongly in the infrared, so instruments for carrying our measurements in this region differ from those used for the electronic (visible/ultraviolet) region. 

In the ultraviolet region of the spectrum quartz optical materials are required. There are some plastic materials that may also be used in the... 

OPTICAL CRYSTAL. A comparatively large crystal, either natural or synthetic, used for infrared and ultraviolet optics, piezoelectric effects, and shortwave radiation detection. Examples are sodium chloride, potassium iodide, silver chloride, calcium tluonde, and (for scintillation counters) such organic materials as anthracene, naphthalene, shlbene, and lerphenyl. 

When working in the ultraviolet spectral region, use is made of quartz optics, and in the infrared region, salt prisms are employed (prisms made of Na Cl, LiF and KBr, depending on the wavelength) the common radiation sources are lamps or (in the infrared region) glowing rods made of specific materials. 

Some ceramics are transparent to light of specific frequencies. These optical ceramics are used as windows for infrared and ultraviolet sensors and in radar installations. However, optical ceramics are not as widely used as glass materials in applications in which visible light must be transmitted. An electro-optic ceramic such as lead lanthanum zirconate titanate is a material whose ability to transmit light is altered by an applied voltage. These electro-optic materials are used in color filters and protective goggles, as well as in memory-storage devices. 

The designer of optical systems must base the selection of optical materials on a knowledge of optical, physical, thermal and mechanical properties. Frequently, the selection of the materials must result from a trade-off analysis as no one material has an ideal set of properties. This compilation of Optical Materials Properties Data Sheets summarizes the vital properties, needed to select an optical material for use in the ultraviolet, visible and infrared regions of the electromagnetic spectrum. Forty-nine materials are described in this conpilation and each sheet of two pages presents the properties of a particular material. The listed properties... 

Once a sample has been transferred to a TLC plate, all the components of that sample will be located somewhere on the layer. If the analyte is colored, localization is simple. Most organic compounds are not colored, however, so special techniques are required to change the materials in such a way that some optical contrast is established in the visible or the ultraviolet region. Reagents useful in color formation have been listed in [1]. 

Besides nanodays, zinc oxide (ZnO) is also a notable inorganic material that can offer optical transparency and shielding to ultraviolet light when used in polymer matrix to prepare nanocomposites 2). 

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