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1984
In the following sections, we shall discuss a variety of field and laboratory measurements on telecommunication fibers, largely excluding sources, detectors and electronics. Certain of these measurements, especially bandwidth and attenuation, will often yield different results for different launching conditions.
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In the following sections, we shall discuss a variety of field and laboratory measurements on telecommunication fibers, largely excluding sources, detectors and electronics. Certain of these measurements, especially bandwidth and attenuation, will often yield different results for different launching conditions.
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MEASURING NON-SPHERICAL OPTICAL SURFACES
Contact Lens and Anterior Eye, 2001More lens designs for the presbyopic market are emerging and the use of novel constructions to generate varifocal optics in contact lenses is increasing. A number of designs incorporate aspheric shapes, of known p-values on the front and back surface of contact lenses.
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Optical Measurement Techniques
2021The characterisation as well as improvement of various photonic devices, functional nanomaterials and quantum structures heavily relies on advanced optical tools. These tools typically incorporate suitable light sources and detection schemes to probe properties of the target system optically. Through special measurement techniques, one can for instance
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Optical Surface Temperature Measurement
1996A crucial problem of realizing the international thermonuclear experimental reactor — ITER - is to handle the energy flux into the scrape off layer (SOL) and to control the energy flux onto the divertor plates. A main topic in research programs of present day tokamaks is to find operation regimes realizing simultaneously a high energy flux into the SOL
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Optical measurement of aero-optics
OSA Annual Meeting, 1993Optical measurements of aerodynamically induced optical degradation have evolved over the last few decades from commerical optical testing instruments to specialized aero-optic diagnostic systems. New diagnostic systems feature vastly increased temporal and spatial resolution and accuracy.
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Optical Pachometry Measurements
Optometry and Vision Science, 1984Polymethyl methacrylate (PMMA) lenses of known thickness were measured by one investigator with a pachometer. This experienced pachometrist held variation in thickness measurements to within 1% over time. The measurements were repeatable with a SD less than 1%.
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2018
A monochromatic light is quantified by its brightness and color, i.e., its optical power and wavelength. And a light beam is normally composed of many monochromatic lights of different powers and wavelengths. In this chapter we discuss three optical dispersive devices, namely, prism, diffraction grating, and Fourier transform spectroscopy, to resolve ...
Wei Lu, Ying Fu
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A monochromatic light is quantified by its brightness and color, i.e., its optical power and wavelength. And a light beam is normally composed of many monochromatic lights of different powers and wavelengths. In this chapter we discuss three optical dispersive devices, namely, prism, diffraction grating, and Fourier transform spectroscopy, to resolve ...
Wei Lu, Ying Fu
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1978
Two disadvantages with the direct measurement of distance discussed in chapter 1 are, firstly, that the measuring process takes place on the ground (if the terrain is undulating this can be very difficult) and, secondly, when a lot of linear measurements are required, taping can be laborious and time consuming.
J. Uren, W. F. Price
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Two disadvantages with the direct measurement of distance discussed in chapter 1 are, firstly, that the measuring process takes place on the ground (if the terrain is undulating this can be very difficult) and, secondly, when a lot of linear measurements are required, taping can be laborious and time consuming.
J. Uren, W. F. Price
openaire +1 more source