Mirrors and Lenses

The IR intensity of IR flares is measured by using a radiometer which consists of both optical and electronics systems. The radiometer uses the optical system consisting of mirrors and lenses to collect the radiation emitted by the object and focuses this radiation upon an IR detector which converts it into an electrical signal. This signal after amplification is processed by the computer system where it is stored. This stored data can be displayed on the monitor and printed. 

If the flame background emission intensity is reduced considerably by use of an inert gas-sheathed (separated) flame, then an interference filter may be used rather than a monochromator, to give a non-dispersive atomic fluorescence spectrometer as illustrated in Figure 14.36-38 Noise levels are often further reduced by employing a solar blind photomultiplier as a detector of fluorescence emission at UV wavelengths. Such detectors do not respond to visible light. The excitation source is generally placed at 90° to the monochromator or detector. Surface-silvered or quartz mirrors and lenses are often used to increase the amount of fluorescence emission seen by the detector. 

The next contributor to the embryonic science of optics was the Arab mathematician and physicist Alhazen (965-1039), who is sometimes called the greatest scientist of the Middle Ages. Experimenting around the year 1000, he showed that light comes from a source (the Sun) and reflects from an object to the eyes, thus allowing the object to be seen. He also studied mirrors and lenses and further refined the laws of reflection and refraction. 

Virtually instantaneous and rugged, PDAs have yet to be fully utilized in process control. Larger models are difficult to use for production as they were designed for static samples. They also require collection of the light diffusely reflected from the solid samples via mirrors and lenses. Most commercial designs are excellent for lab use, but not rugged enough for the production line. 

Losses of radiation by reflection or refraction at the environment/ cuvette/sample interfaces are a consequence of the establishment of mirrors and lenses. A mirror is just an interface between two transparent media with different refractive indices, whereas different interface shapes can give rise to the formation of lenses. As the influence of these artefacts is strongly dependent on the collimation of the incident beam, the proportion of lost radiation is minimised by properly designing the shape of the cuvette and using a spectrophotometer with good optical characteristics [2],... 

Little attention has been given to the influence of these transient liquid mirrors and lenses on the amount of stray light reaching the detector. Investigation of this process is strongly recommended, as the Schlieren effect can lead to an increase in detected radiation, hence degrading the linearity of the analytical response curve [13]. 

The exposure optics system comprises the set of optics (mirrors and lenses) that delivers the aerial image of the mask to the resist-coated wafer on the exposure stage. There are two categories of such systems. Contact and proximity optics systems are the simplest and the least expensive of the systems, but are not well suited for high-volume IC manufacture because of their high level of defectivity. The other system, the projection optics system, is predominantly used in modern semiconductor manufacturing. Both systems rely on the entire mask, or at least a portion of it, to be imaged simultaneously. 

An increase of solar illumination by a factor of 5 while reducing the efficiency to 6% (see Fig. 10) yields an acceptable initial investment of 164/m2. If the mirrors and lenses needed to concentrate sunlight are cheaper than the semiconducting film, the cell may be most economical under high illumination. The values presented here can be compared to the cost estimate of 0.34 per peak watt presented by Weaver et al225 for a GaAs photoelectrochemical cell. Their estimate is based on materials cost (see also Refs. 226 and... 

The basic instrumentation requirements for analytical atomic fluorescence are quite modest. A simple instrumental arrangement is shown in Figure 11-2, and includes (1) an excitation source, (2) a sample cell, (3) a monochromator, (4) a detector, and (5) a read-out system. Mirrors and lenses can be used at appropriate positions along the optical path to collect the radiant energy and thereby increase its intensity. 

The shock wave travels through the PMMA discs and successively closes the optical barriers, thus changing the total intensity of the reflected laser beam. The reflected laser beam is then directed to the photomultiplier by a system of mirrors and lenses. The output signal from the photomultiplier is recorded by a fast oscilloscope that has a time resolution on the nanosecond scale. 

When the target velocity is to be determined, the laser beam is sent to the moving target. The target surface is prepared to produce a diffuse reflected beam. Mirrors and lenses are used to direct the reflected beam as a parallel one to the Fabry-Perot interferometer. 

See also Audio Engineering Computer Graphics Mirrors and Lenses Optics Photography Television Technologies Video Game Design and Programming. 

See also Electron Microscopy Histology Liquid Crystal Technology Mirrors and Lenses Nanotechnology Optics. 

Catadioptric Imaging Ims ing system that uses a combination of mirrors and lenses to create an optical system. 

Cameras also make use of both mirrors and lenses. In single-lens reflex (SLR) cameras, the film or... 

Lens and mirror systems are also indispensable as tools in a larger research apparatus. Microscopes, highspeed cameras, and other digital equipment are commonplace in biological, chemical, and physical science laboratories, and many experimental setups include custom-made imaging equipment all based on combinations of mirrors and lenses. 

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