scholarly journals Reflective Optics Design for an LED High Beam Headlamp of Motorbikes

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Peng Ge ◽  
Xiang Wang ◽  
Yang Li ◽  
Hong Wang
Keyword(s):  
Monte Carlo ◽  
Design Method ◽  
Physical Object ◽  
United Nations Economic Commission ◽  
High Beam ◽  
Light Pattern ◽  
Economic Commission ◽  
Reflective Optics ◽  
Freeform Optics ◽  
Optics Design

We propose a reflective optics design for an LED motorbike high beam lamp. We set the measuring screen as an elliptical zone and divide it into many small lattices and divide the spatial angle of the LED source into many parts and make relationships between them. According to the conservation law of energy and the Snell’s law, the reflector is generated by freeform optics design method. Then the optical system is simulated by Monte Carlo method using ASAP software. Light pattern of simulation could meet the standard. The high beam headlamp is finally fabricated and assembled into a physical object. Experiment results can fully comply with United Nations Economic Commission for Europe (ECE) vehicle regulations R113 revision 2 (Class C).

scholarly journals Asymmetric Double Freeform Surface Lens for Integrated LED Automobile Headlamp

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 663
Author(s):  
Hui Zhang ◽  
Dengfei Liu ◽  
Yinwan Wei ◽  
Hong Wang
Keyword(s):  
Optical System ◽  
Design Method ◽  
Chromatic Dispersion ◽  
Electronic Devices ◽  
Color Temperature ◽  
Freeform Surface ◽  
United Nations Economic Commission ◽  
System A ◽  
Economic Commission ◽  
Key Points

We propose a design method of asymmetric double freeform surface lens for an integrated LED automobile headlamp and develop an integrated LED automobile optical system. A single asymmetric double freeform surface lens is designed to redistribute rays emitting from the light source for realizing both low and high beams. Moreover, a freeform surface reflector is used to improve the energy efficiency of high beams. The prism placed in the optical path can suppress chromatic dispersion on the edge of the target plane. Simulation and experimental results show that the illumination values and color temperature of the key points can fully meet the requirements of United Nations Economic Commission for Europe vehicle regulations (ECE) R112, 48, and 128. The volume of the whole optical system comprised of freeform surface elements is smaller than that of the low beam system of a traditional headlamp, resulting in saved space, in which other electronic devices can be installed for the safety of the driver, which indicates that the proposed method is practical in the field of automobile lighting.

scholarly journals Towards automatic freeform optics design: coarse and fine search of the three-mirror solution space

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Benqi Zhang ◽  
Guofan Jin ◽  
Jun Zhu
Keyword(s):  
Optical System ◽  
Design Method ◽  
Solution Space ◽  
Optical Power ◽  
Labor Costs ◽  
Diverse Range ◽  
The Past ◽  
Freeform Optics ◽  
Optics Design ◽  
Significant Effort

AbstractDesign of an optical system, whether classic or novel, in the past or the present, requires significant effort from the designer. In addition to design methods and theories, the designer’s skills and experience in optical system design are particularly important, which may require years of practice to learn. The diversity and variety of results are limited because of the difficulty, time, and labor costs required. In this article, we propose an automatic design method for freeform optics that can achieve a diverse range of three-mirror designs. The optical specifications and the design constraints are the only inputs required, and a variety of results can be obtained automatically. The output results have various structures and various optical power distributions with high imaging qualities. By implementing the design method, designers can not only realize an overview of the solution space of the three-mirror freeform system, but can also focus on specific designs.

A freeform optics design with limited data for extended LED light sources

2016 ◽  
Vol 63 (21) ◽  
pp. 2151-2158 ◽  
Author(s):  
Zhenfeng Zhuang ◽  
Phil Surman ◽  
Feihong Yu
Keyword(s):  
Light Sources ◽  
Limited Data ◽  
Led Light ◽  
Freeform Optics ◽  
Optics Design

Haile Selassie's Imperial Modernity: Expatriate Architects and the Shaping of Addis Ababa

2016 ◽  
Vol 75 (4) ◽  
pp. 447-468 ◽  
Author(s):  
Ayala Levin
Keyword(s):  
United Nations ◽  
Addis Ababa ◽  
African Unity ◽  
United Nations Economic Commission ◽  
The Past ◽  
Economic Commission ◽  
Organization Of African Unity ◽  
The 1960S ◽  
The Individual ◽  
The City

In the 1960s, Addis Ababa experienced a construction boom, spurred by its new international stature as the seat of both the United Nations Economic Commission for Africa and the Organization of African Unity. Working closely with Emperor Haile Selassie, expatriate architects played a major role in shaping the Ethiopian capital as a symbol of an African modernity in continuity with tradition. Haile Selassie's Imperial Modernity: Expatriate Architects and the Shaping of Addis Ababa examines how a distinct Ethiopian modernity was negotiated through various borrowings from the past, including Italian colonial planning, both at the scale of the individual building and at the scale of the city. Focusing on public buildings designed by Italian Eritrean Arturo Mezzedimi, French Henri Chomette, and the partnership of Israeli Zalman Enav and Ethiopian Michael Tedros, Ayala Levin critically explores how international architects confronted the challenges of mediating Haile Selassie's vision of an imperial modernity.

The Aarhus Convention and Polish Regulations Concerning Parties to Proceedings for Issuing the eia Decisions

2021 ◽  
Vol 18 (1-2) ◽  
pp. 56-76
Author(s):  
Magdalena Michalak ◽  
Przemysław Kledzik
Keyword(s):  
Environmental Law ◽  
Legal Order ◽  
Access To Justice ◽  
United Nations Economic Commission ◽  
The Public ◽  
Law And Policy ◽  
Economic Commission ◽  
Aarhus Convention ◽  
Key Issues ◽  
Environmental Law And Policy

Abstract The United Nations Economic Commission for Europe Convention on Access to Information, Public Participation in Decision-Making and Access to Justice in Environmental Matters was adopted on 25 June 1998 in the Danish city of Aarhus. According to its provisions each state Part shall, within the framework of the national legal order, ensure that members of the public concerned have access to a review procedure before a court of law or another independent and impartial body established by law. At the same time, it contains regulations specifying the criteria that constitute the basis for determining persons enjoying rights to access justice with respect to national legal orders. Poland, being one of the state Parties, introduced into national legal order special provisions enabling implementation of the Aarhus Convention, including regulations concerning parties to proceedings in environmental matters. The aim of the study is to analyse and assess these regulations in the light of the requirements adopted in the Aarhus Convention and to formulate general conclusions in the field of key issues of the international and European environmental law and policy.

The UN Economic Commission for Latin America (CEPAL) and the Development Project

2021 ◽  
Author(s):  
Margarita Fajardo
Keyword(s):  
Economic Development ◽  
Latin America ◽  
World War Ii ◽  
International Development ◽  
Global Economy ◽  
Raw Materials ◽  
New Left ◽  
Development Project ◽  
United Nations Economic Commission ◽  
Economic Commission

The United Nations Economic Commission for Latin America (ECLA in English and CEPAL in Spanish and Portuguese) was more than an economic development institution. Established in 1948, at the height of post-World War II internationalism, CEPAL was one of the first three regional commissions alongside those of Europe and Asia charged with addressing problems of postwar economic reconstruction. But, in the hands of a group of mostly Argentinean, Brazilian, and Chilean economists, CEPAL swiftly became the institutional fulcrum of a regional intellectual project that put Latin America at the center of discussions about international development and global capitalism. That Latin America’s place in the periphery of the global economy as a producer of primary products and raw materials in exchange for manufactured goods from the world’s industrial centers, combined with the long-term decline in the international terms of that trade, constituted an obstacle for economic development, was the foundational tenet of that project. Through regional economic surveys and in-depth country studies, international forums and training courses, international cooperation initiatives, and national structural reforms, cepalinos located themselves at the nexus of a transnational network of diplomats and policymakers, economists and sociologists, and made the notion of center–periphery and the intellectual repertoire it inspired the central economic paradigm of the region in the postwar era. Eclipsed in the 1970s by critiques from the New Left and dependency theorists, on the one hand, and by the authoritarian right and neoliberal proponents, on the other hand, the cepalino project remains Latin America’s most important contribution to debates about capitalism and globalization, while the institution, after it reinvented itself at the turn of the century, still constitutes a point of reference and a privileged repository of information about the region.

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