A 90° bend curved light-guide for TOF scintillating detectors

Although powdered phosphor screens are usually used for scintillators of STEM, it has been found that the phosphor screen of appropriate thickness should be used depending on the accelerating voltage, in order to keep high detective quantum efficiency. 1 It has been also found that the variation in sensitivity, due to granularity of phosphor screens, makes the measurement of fine electron probe difficult and that the sensitivity reduces with electron irradiation specially at high voltages.In order to find out a preferable scintillator for STEM, single crystals of YAG (yttrium aluminum garnet), which are used for detecting secondary and backscattered electrons in SEM were investigated and compared with powdered phosphor screens, at the accelerating voltages of 100kV and 1 MV. A conventional electron detection system, consisting of scintillator, light guide and PMT (Hamamatsu Photonics R268) was used for measurements. Scintillators used are YAG single crystals of 1.0 to 3.2mm thicknesses (with surfaces matted for good interface to the light guide) and of 0.8mm thickness (with polished surface), and powdered P-46 phosphor screens of 0.07mm and 1.0mm thicknesses for 100kV and 1MV, respectively. Surfaces on electron-incidence side of all scintillators are coated with reflecting layers.

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Daylight in Underground Spaces

Light & Engineering ◽

10.33383/2017-028 ◽

2018 ◽

pp. 156-161

Author(s):

Alexei K. Solovyov

Keyword(s):

Light Guide ◽

Heat Losses ◽

Internal Environment ◽

Method Of Calculation ◽

Natural Lighting ◽

Different Depths ◽

The Common ◽

Different Diameters

Underground spaces in town centres present a big attraction for investors. However, they put special requirements to the internal environment. Those requirements can be fulfilled by means of daylighting. Examples of lighting of underground spaces are discussed. It is shown that the common systems of natural lighting are not always possible to use and cause big heat losses. Hollow light guide pipes allow avoid the shortcomings of common daylight systems. Method of calculation of daylight factors from hollow light guide pipes is shown. The results of calculation of daylight factors under the light guide pipes of different diameters in the different depths are presented.

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Development of On-line Fiber Orientation Meter Based on the Light Guide Effect

JAPAN TAPPI JOURNAL ◽

10.2524/jtappij.58.220 ◽

2004 ◽

Vol 58 (2) ◽

pp. 220-225

Author(s):

Yuji Abe ◽

Hidenobu Todoroki

Keyword(s):

Fiber Orientation ◽

Light Guide ◽

On Line

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Moldability improvement in microinjection molding via film lamination

Polymers and Polymer Composites ◽

10.1177/0967391120986503 ◽

2021 ◽

pp. 096739112098650

Author(s):

Dah Hee Kim ◽

Young Seok Song

Keyword(s):

Heat Transfer ◽

Light Guide ◽

Wall Slip ◽

Skin Layer ◽

Pattern Transfer ◽

Plastic Plate ◽

Resin Infusion ◽

Microinjection Molding ◽

Insulation Effect ◽

Thin Plastic

The purpose of this study is to integrate a polymeric film onto a mold to impede thermal heat transfer during resin infusion. A thin plastic plate was fabricated by using microinjection molding. A polyimide (PI) film was laminated onto a mold in an effort to produce a thin light guide plate (LGP). The film could decelerate the solidification of molten polymer in the cavity of mold and enhance the wall slip of resin on the mold. The insulation effect was modeled numerically. The surface roughness and pattern transfer characteristics of the LGP were evaluated. It was found that the fluidity of the resin increased due to the decreased skin layer during mold filling. The results showed that the strategy proposed in this study could help decrease the thickness of LGP effectively when manufacturing the part via injection molding.

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P-70: Light Shifted Light-guide Plate for Simple Multi-view Spatial/Temporal Hybrid Autostereoscopic Display

SID Symposium Digest of Technical Papers ◽

10.1002/sdtp.10940 ◽

2016 ◽

Vol 47 (1) ◽

pp. 1399-1401 ◽

Cited By ~ 1

Author(s):

Gun-Wook Yoon ◽

Seok-Won Bae ◽

Hyun-Seung Cho ◽

Jun-Bo Yoon

Keyword(s):

Light Guide ◽

Autostereoscopic Display ◽

Light Guide Plate ◽

Guide Plate

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A Side-Absorption Concentrated Module with a Diffractive Optical Element as a Spectral-Beam-Splitter for a Hybrid-Collecting Solar System

Energies ◽

10.3390/en13010192 ◽

2020 ◽

Vol 13 (1) ◽

pp. 192

Author(s):

An-Chi Wei ◽

Wei-Jie Chang ◽

Jyh-Rou Sze

Keyword(s):

Fill Factor ◽

Beam Splitter ◽

Light Guide ◽

Solar Spectrum ◽

Optical Element ◽

Grating Period ◽

Infrared Light ◽

Solar Systems ◽

Module Efficiency ◽

Energy Conversion Devices

In this paper, we propose a side-absorption concentrated module with diffractive grating as a spectral-beam-splitter to divide sunlight into visible and infrared parts. The separate solar energy can be applied to different energy conversion devices or diverse applications, such as hybrid PV/T solar systems and other hybrid-collecting solar systems. Via the optimization of the geometric parameters of the diffractive grating, such as the grating period and height, the visible and the infrared bands can dominate the first and the zeroth diffraction orders, respectively. The designed grating integrated with the lens and the light-guide forms the proposed module, which is able to export visible and infrared light individually. This module is demonstrated in the form of an array consisting of seven units, successfully out-coupling the spectral-split beams by separate planar ports. Considering the whole solar spectrum, the simulated and measured module efficiencies of this module were 45.2% and 34.8%, respectively. Analyses of the efficiency loss indicated that the improvement of the module efficiency lies in the high fill-factor lens array, the high-reflectance coating, and less scattering.

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In vivo Percutaneous Absorptiometry by a Laser Photoacoustic Method Using a Novel Open-Ended Cell Combined with Light Guide

Analytical Chemistry ◽

10.1021/ac00086a011 ◽

1994 ◽

Vol 66 (14) ◽

pp. 2267-2271 ◽

Cited By ~ 6

Author(s):

Ryuichi. Takamoto ◽

Shinya. Yamamoto ◽

Ryujiro. Namba ◽

Tasuku. Takamatsu ◽

Masahiro. Matsuoka ◽

...

Keyword(s):

Light Guide ◽

Photoacoustic Method

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Optimising the AR Engraved Structure on Light-Guide Facets for a Wide Range of Wavelengths

Optics ◽

10.3390/opt2010002 ◽

2020 ◽

Vol 2 (1) ◽

pp. 25-42

Author(s):

Ioseph Gurwich ◽

Yakov Greenberg ◽

Kobi Harush ◽

Yarden Tzabari

Keyword(s):

Theoretical Analysis ◽

Light Guide ◽

Spectral Band ◽

Angular Range ◽

The Past ◽

Input And Output ◽

Wide Range ◽

The Given ◽

Theoretical Results ◽

Shape And Size

The present study is aimed at designing anti-reflective (AR) engraving on the input–output surfaces of a rectangular light-guide. We estimate AR efficiency, by the transmittance level in the angular range, determined by the light-guide. Using nano-engraving, we achieve a uniform high transmission over a wide range of wavelengths. In the past, we used smoothed conical pins or indentations on the faces of light-guide crystal as the engraved structure. Here, we widen the class of pins under consideration, following the physical model developed in the previous paper. We analyze the smoothed pyramidal pins with different base shapes. The possible effect of randomization of the pins parameters is also examined. The results obtained demonstrate optimized engraved structure with parameters depending on the required spectral range and facet format. The predicted level of transmittance is close to 99%, and its flatness (estimated by the standard deviation) in the required wavelengths range is 0.2%. The theoretical analysis and numerical calculations indicate that the obtained results demonstrate the best transmission (reflection) we can expect for a facet with the given shape and size for the required spectral band. The approach is equally useful for any other form and of the facet. We also discuss a simple way of comparing experimental and theoretical results for a light-guide with the designed input and output features. In this study, as well as in our previous work, we restrict ourselves to rectangular facets. We also consider the limitations on maximal transmission produced by the size and shape of the light-guide facets. The theoretical analysis is performed for an infinite structure and serves as an upper bound on the transmittance for smaller-size apertures.

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