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In this contribution, we put forward an analytical model for the design of lossless and lossy nanoparticle-based metasurfaces working at a desired frequency in the optical spectrum. To show the versatility of our approach, we exploit it for the design of different innovative devices, such as cloaking-inspired anti-reflection coatings, circuit-analog screens and narrowband optical absorbers that are...
Polymethyl Methacrylate (PMMA) is an important macromolecule material with high plasticity, which is also widely used in the manufacturing of LED diffusion plates, because it has several advantages, such as excellent optical transparency, chemical stability, good weather resistance, radiation resistance and surface hardness (no scratch). It also can be completely recycled and easy processing. However,...
Portable solar chargers have been gaining popularity as a new technology to help increase electrification in rural areas in developing countries. It is a fast developing industry aiming to produce a low-cost solution for the application of off-grid solar lighting and charging of small devices to be used by the poorest and most vulnerable of society. Solar concentrators are proposed as an add-on to...
A simple design of an ultrabroadband and high-efficiency reflective linear polarization convertor is presented in the optical frequency region. This ultrabroadband convertor is formed from the planar anisotropic metasurface using a meander wire structure. The numerical simulation demonstrates that the polarization conversion ratio over 90% is achieved from 181 to 506 THz, which is equivalent to 94...
In this paper, we present the simulation results using simulated annealing method in the preliminary optical design for the hollow cavity of a thin rectangular small-size edge-type hollow-cavity LED luminaire. The simulation results demonstrated its feasibility of commercial use with both illuminance uniformity and light extraction efficiency of above 80% on the emission surface of its hollow cavity.
This paper proposes a new design method for a novel secondary optical element to generate uniform illumination on a target plane. This design is based on a Dielectric Totally Internally Reflecting Concentrator and uses Total Internal Reflection at the side profile of the lens.
A direct LED backlight unit (DLBLU) with extended sources based on an analytical design method of uniform illumination is investigated. We developed an analytical calculation method of the light spread function (LSF) for achieving highly uniform illumination into the diffuser plate (target plane) of a DLBLU. The effect of the rays reflected by the sides of the backlight box was also considered and...
The paper presents the results of analysis of losses in a typical optical systems used for forming luminous intensity distribution of LED sources in the context of the application for road lighting. There was discussed the characteristics of LEDs and issues related to energy efficiency of lighting. There was shown typical optical systems, containing reflecting and refracting elements, discussed their...
Developing a system to monitor the biological status of a driver is method to increase smart function of car. When the biological condition of driver is unstable, it can sound warning or provide the control strategy not only to reduce the possible damage to the road traffic safety caused by the driver's disablement but also the quantity of the traffic accident. In order to monitor the biological status...
The tutorial will focus on physics governing short and high frequency pulse generation in semiconductor lasers and on generating sub-picosecond pulses at frequencies from GHz to THz. Techniques for engineering the laser cavity include reduced optical overlap, harmonic mode-locking and sampled DBR reflectors and filters.
A novel fully integrated tunable single mode hybrid silicon laser is demonstrated. We report a linewidth of 260kHz, which is the lowest reported for a monolithically integrated laser. The side-mode suppression ratio is >40dB.
Concentrating optics generally produce spatially and spectrally non-uniform optical profiles across the multijunction solar cells typically used in a concentrator photovoltaic (CPV) systems, degrading fill factors and thereby reducing module efficiencies. These effects maybe more pronounced if the primary-to-secondary distance is sub-optimal and if the system does not track the sun accurately. We...
A surface relief diffractive optical element (DOE) for photovoltaic (PV) spectrum splitting is fabricated and tested. The optic is designed using a modified Gerchberg-Saxton algorithm. The module consists of a DOE followed by a 3.3 cm focal length lens. Alternating side-by-side PV cells - Indium Gallium Phosphide and Silicon - are placed at the collection plane. The DOE is fabricated in photopolymer...
Immersion graded refractive index optics enable passive optical concentrators, but also present challenges in design, fabrication, and integration. In this paper, we describe two simple and scalable fabrication techniques and report on the performance of prototypes. We present two tileable designs and demonstrate a passive concentration of 3 Suns.
There will be 50 diagnostic systems installed on ITER. All have been implemented with great success on experimental fusion reactors around the world. Despite this deep experience, implementation of diagnostic systems on ITER remains very challenging. Structural, nuclear and optical engineering challenges arise from loads that are at least an order of magnitude higher and last for much longer than...
The enhanced visible light communications (VLC) system with transmission distance of 7m is demonstrated using transmission path design and forward error correction code in this paper. Moreover, RS (160, 128) and LDPC (960, 480) code are implemented and experimented via VLC test-bed. The results suggest that based on the given power, 5Mbps transmission bit rate and 10−3 bit error rate (BER), in comparison...
A novel secondary optical design for LED lamps with high color rendering indices (CRI) and adjustable correlated color temperature (CCT) is proposed. RGB LED cells are assembled in a three dimensional manner together with a set of beam mixers. Perfect light mixing is resulted by optimizing the structural parameters of the reflectors and beam mixers. A supplement amber LED is used for light compensation...
In order to address the existing star tracker's problem of large size and on-orbit gluing, a new telemetric optical system is designed in this paper. And the optical system has a large field of view, a high precision and a small size. Firstly, the optical system's engineering requirements are described and its design specifications are calculated. Based on the calculated results, the initial structure...
Based on the principle of optical designing and adjusting, by simulated the lighting and imaging of two-dimensional optical system, analyzed the influence of the location of the reflect optical element to the optical system at the situation that the aperture has restriction, finally deduced the formula between the spacing of the reflect element, the tilt reflect angle, the F number and the reflect...
A novel secondary optical design for LED lamps with high color rendering indices (CRI) and adjustable correlated color temperature (CCT) is proposed. RGB LED cells are assembled in a three dimensional manner together with a set of beam mixers. Perfect light mixing is resulted by optimizing the structural parameters of the reflectors and beam mixers. A supplement amber LED is used for light compensation...
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