No description available.

This research developed the Optical Light Pipe (OLP) as a feasible solution to solve the problem of insufficient daylighting in deep plan office spaces for predominantly sunny climates. It further combined the OLP with a Specular Light Shelf (SLS) to achieve uniform daylighting. This research was performed with an experimental setup of two 1:4 scale models of deep plan office spaces, modified from an earlier research on optical light pipe at College Station, TX. Blinds and shading devices were installed on the south façade to provide daylight to the front zone of a 20 feet by 30 feet office module. The back zone was daylit by the OLP hidden in the plenum. The existing OLP design was optimized through computer aided ray-tracing. The SLS design was based on an earlier prototype designed at Lawrence Berkeley National Labs (LBNL). Results were based on observations made on clear and cloudy sky days between February 3rd and March 17th. The OLP achieved more than 300 lux of average workplane illuminance for 7.4 hours, when global horizontal illuminance was greater than 40,000 lux. It also achieved 200 lux of illuminance higher than an earlier prototype (Martins-Mogo, 2005) on workplane between 1000hrs and 1630hrs. It exhibited a glare free daylight distribution with luminance ratios well within prescribed limits on most of the vertical surfaces, with a relatively uniform illuminance distribution on back taskplane. OLP was better than windows with blinds and shading at providing diffuse daylight in backzone on a cloudy day, when global horizontal illuminance was greater than 20,000 lux. The OLP used in combination with SLS achieved more than 500 lux of average workplane illuminance for 6 hours, when global horizontal illuminance was greater than 40,000 lux. SLS also produced more uniform illuminance levels on the workplane at all times and on the leftwall at most times. However, it produced non-uniform luminance distribution on walls and ceiling and luminance ratios higher than allowable limits on the sidewall for some morning hours, and hence needed further refinement in design.

We report that the tandem OLEDs made of two electroluminescent (EL) units connected by the interconnecting layer. If It is compared wih the traditional OLEDs. The tandem OLEDs have higher efficiency and well lifetime. We not only used the single emitting layer WOLEDs as EL unit but also studied the effect of the interconnecting layer for whole device. First, we designed the interconnecting layer with Alq3¡GLi (1%) (n-doping layer)/MoO3 (p-doping layer), and we optimized the thickness of the interconnecting layer by using green unit cell (Alq3 for EML), ITO/NPB(65 nm)/Alq3(30 nm)/Alq3(30 nm)/Alq3(x nm)¡GLi (1%)/MoO3(y nm)/NPB(65 nm)/Alq3(30 nm)/Alq3(30 nm)/LiF(0.8 nm)/Al(200 nm) x=10¡A20¡A30¡A40¡Fy=1¡A3¡A5¡A7¡A10 We found that the best thickness of Alq3¡GLi (1%) and MoO3 are 20 nm and 5 nm. In our study, we concluded that there are the best thickness to each interconnecting layer, and it keeps the charge balance between two units. Finally, we used our single emitting layer WOLEDs as unit cell, which used 1,3,5-Tri(1-pyrenyl)benzene (TPB3) as the host, and 4-(dicyanomethylene)-2-tert-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran (DCJTB) as the guest, unit cell was ITO(130 nm)/NPB(65 nm)/ TPB3(30 nm)¡GDCJTB(0.05%)/ Alq3(30 nm)/LiF(8 nm)/Al(200 nm) Whole device was ITO(130 nm)/NPB(65 nm)/ TPB3(30 nm)¡GDCJTB(0.05%)/ Alq3(30 nm)/Alq3(20 nm)¡GLi(1%)/MoO3(5 nm)/NPB(65 nm)/TPB3(30 nm)¡GDCJTB(0.05%)/Alq3(30 nm)/ LiF(0.8 nm)/Al(200 nm) We got almost three times luminance from the tandem one at the same current density (670 cd/m2 for 2360 cd/m2 at 20 mA/cm2) and efficiency as high as 9.7 cd/A ( at 24 mA/cm2). It¡¦s a excellent contribution for device lifetime. But the operation voltage and the power efficiency didn¡¦t reach to our expectancy. In order to improve the disadvantage, we changed the concentration of n-doping layer Alq3¡GLi (z %)¡Az=1%¡A2%¡A3%. It was actually improved the turn-on voltage from 10 V to 7 V. But the luminescent characteristics also degenerated. Although we enhanced the charge mobility of the n-doping layer, it also caused the degeneration of luminescent characteristics because of the unbalance of the charge transference.We got the efficiency 8.1 cd/A ( at 14 V) and almost two times luminance from the tandem one at the same current density (670 cd/m2 for 1760 cd/m2 at 20 mA/cm2), most close to the white area of CIE coordinates was (0.30 , 0.37) at 15 V. Its range of CIE coordinates was (0.35 , 0.46)~(0.28 , 0.33) at 8 V~20 V. We have already developed the tandem WOLEDs using single white emitting layer as EL units that have never be reported. It not only maintained the advantages of the tandem structure, but also had excellent stability of luminescent characteristics at wide range operation voltage. We reached our goal to improve the WOLEDs and make it more suitable for commercial applications, especially for the development of light sources.

Thesis (M.S.)--Rochester Institute of Technology, 2007. / Typescript. Includes bibliographical references (leaves 130-139).

A miniaturized spatial light modulator (SLM)-based structured-light illumination module with optical fiber input is designed to generate a coded 256 x 256 spots pattern for 3-D areal mapping applications. The projector uses the light from a He-Ne laser coupled to a polarization-maintaining (PM) fiber to illuminate a specially made hologram so that four virtual point sources are regenerated. The interference pattern of the four sources are filtered and modulated by an SLM. The output intensity can thus be encoded to form any arbitrary pattern through the electronic input applied to the SLM with a high speed. In this thesis, a complete optical diffraction analysis of the system is presented to provide guidelines for the optimal design of the system parameters. Through the theoretical analysis for square beam array generation, the important parameters for fabricating a hologram are given. The final system optical design and arrangement based on optical analysis are described. The detailed opto-mechanical construction of the LIM and the associated alignment, the computer simulation and the preliminary test results of the developed LIM are also provided. / Master of Science

Digitized by Kansas State University Libraries

No description available.

No description available.

This thesis gives an account of experiments which investigate the detection of light by, and the emission of light from, planar metal-oxide-metal (M-O-M) tunnel junctions. The particular focus of attention is the mediation of these processes by surface plasmons, or surface electromagnetic waves bound to metal-dielectric interfaces, in the two processes. It describes how the coupling of incident bulk radiation to a surface plasmon supported by the junction structure may enhance the response of the device when used as a photodetector. This idea is then extended to cover other electromagnetic resonances supported by the junction system in different operating configurations. There is a brief departure from M-O-M devices to consider how a metal-semiconductor Schottky barrier diode may also have its photoresponse enhanced in a similar manner by coupling to a surface plasma wave localised at the metal-vacuum interface before returning to M-O-M devices to show that, in addition to their use as discrete detectors, they may also be used as integrated detectors of guided radiation. Attention is then turned onto the reverse process of light emission from M-O-M tunnel junctions. When these devices are 'rough' or are corrugated in some manner and pass a current they emit broadband light with an upper frequency cut-off determined by the applied bias, hv= e<SUP>V<SUB>bias</SUB></SUP>. This light emission process is mediated by the surface plasmons of the structure, of which there are three in the energy range considered. Experimental results on the light emission from residually rough and deliberately roughened junctions are reported. In particular, the results of an experiment are presented which show that the majority of the radiation outcoupled from statistically rough devices is derived from the 'fast' surface plasmon localised at the outer metal surface.

The entire sixteen element scattering matrix for two parallel dielectric fibers over an angular range of θ = 5°-170° as measured from the forward θ = 0 direction has been experimentally measured using the polarization modulation technique. Experimental results were in good agreement with theory for light scattering from two parallel fibers. Measurements were made for both endside and broadside illuminations at normal incidence for fibers at various separations from 2 μm to 70 μm. Laser wavelengths used were 632.8 nm and 441.2 nm, and fiber radii were 0.400±0.002 μm, 0.370±0.002 μm, 0.428±0.002 μm, and 0.406±0.002 μm. Special care was taken to measure the fiber radii, fiber separation, and to establish the parallelism between the two fibers. Electrostatic attraction between the fibers prevented the investigation for separation below 2 μm. A vibration detection device based on two-fiber light scattering has also been suggested.