Beam Pre-Shaping Methods Using Lenslet Arrays for Area-Based High-Resolution Vehicle Headlamp Systems

High-resolution light distributions are lately in demand for vehicle headlamp systems as an innovative lighting approach. This lighting approach can realize functionalities, such as precise glare avoidance and on-road projection, which are useful for improving traffic comfort and safety. For achieving the required high-resolution light distribution, area-based projection technologies, such as DMD, LCD, and LCoS, are considered to be integrated into such headlamps. These projection devices demand rectangular illumination areas with specific light distributions to fulfill the requirements for illumination efficiency and performance in headlamp systems. Lenslet arrays, based on the principle of Köhler illumination, can effectively homogenize the light and shape it into rectangular shapes simultaneously. Such components are widely used in projection applications. However, they also show functional potentialities to be applied in high-resolution headlamps. This paper explains the design principles and methods of lenslet arrays for beam pre-shaping in headlamp systems. It validates the homogenization using a self-designed and manufactured lenslet array in a demonstrator in the first place. Afterward, this paper introduces two new methods for the centralized beam shaping required by some headlamps. These methods are validated by optical simulations.

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Fabrication and Compressive Behavior of a Micro-Lattice Composite by High Resolution DLP Stereolithography

Polymers ◽

10.3390/polym13050785 ◽

2021 ◽

Vol 13 (5) ◽

pp. 785

Author(s):

Chow Shing Shin ◽

Yu Chia Chang

Keyword(s):

High Resolution ◽

Lattice Structure ◽

Low Cost ◽

Hierarchical Structures ◽

Dip Coating ◽

Unit Cell ◽

Digital Light Processing ◽

Unit Cell Size ◽

Wide Range ◽

And Performance

Lattice structures are superior to stochastic foams in mechanical properties and are finding increasing applications. Their properties can be tailored in a wide range through adjusting the design and dimensions of the unit cell, changing the constituent materials as well as forming into hierarchical structures. In order to achieve more levels of hierarchy, the dimensions of the fundamental lattice have to be small enough. Although lattice size of several microns can be fabricated using the two-photon polymerization technique, sophisticated and costly equipment is required. To balance cost and performance, a low-cost high resolution micro-stereolithographic system has been developed in this work based on a commercial digital light processing (DLP) projector. Unit cell lengths as small as 100 μm have been successfully fabricated. Decreasing the unit cell size from 150 to 100 μm increased the compressive stiffness by 26%. Different pretreatments to facilitate the electroless plating of nickel on the lattice structure have been attempted. A pretreatment of dip coating in a graphene suspension is the most successful and increased the strength and stiffness by 5.3 and 3.6 times, respectively. Even a very light and incomplete nickel plating in the interior has increase the structural stiffness and strength by more than twofold.

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High-Resolution Pixel LED Headlamps: Functional Requirement Analysis and Research Progress

Applied Sciences ◽

10.3390/app11083368 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3368

Author(s):

Liping Wang ◽

Jianshe Ma ◽

Ping Su ◽

Jianwei Huang

Keyword(s):

High Resolution ◽

Functional Diversity ◽

Traffic Safety ◽

New Technologies ◽

Light Distribution ◽

Research Progress ◽

Requirement Analysis ◽

Functional Requirement ◽

Traffic Conditions ◽

The Subject

High-resolution pixel LED headlamps are lighting devices that can produce high-resolution light distribution to adapt to road and traffic conditions, intelligently illuminate traffic areas, and assist drivers. Due to the complexity of roads and traffic conditions, the functional diversity of high-resolution pixel LEDs headlamps and traffic safety has come into question and is the subject of in-depth research conducted by car manufacturers and regulators. We summarize the current possible functions of high-resolution pixel LED headlamps and analyze ways in which they could be improved. This paper also discusses the prospect of new technologies in the future.

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Design principles for composition and performance of cultured skin substitutes

Burns ◽

10.1016/s0305-4179(01)00019-5 ◽

2001 ◽

Vol 27 (5) ◽

pp. 523-533 ◽

Cited By ~ 137

Author(s):

Steven T Boyce

Keyword(s):

Design Principles ◽

Skin Substitutes ◽

Cultured Skin ◽

And Performance ◽

Cultured Skin Substitutes

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Handover within 3GPP LTE: Design Principles and Performance

2009 IEEE 70th Vehicular Technology Conference Fall ◽

10.1109/vetecf.2009.5378909 ◽

2009 ◽

Cited By ~ 88

Author(s):

Konstantinos Dimou ◽

Min Wang ◽

Yu Yang ◽

Muhammmad Kazmi ◽

Anna Larmo ◽

...

Keyword(s):

Design Principles ◽

3Gpp Lte ◽

And Performance

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A High Resolution Spectrograph at Weihai Observatory

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313013252 ◽

2012 ◽

Vol 8 (S293) ◽

pp. 400-402

Author(s):

Dongyang Gao ◽

Dayong Ren

Keyword(s):

High Resolution ◽

Echelle Spectrograph ◽

Metal Abundance ◽

And Performance

AbstractWeihai Echelle Spectrograph (WES) is the first the fiber-fed echelle spectrograph in China. WES can provide data for the studies of metal abundance of stars, exoplanets researches and asteroseismology, etc. A brief description of its design and performance is given.

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High resolution Michelson interferometer for airborne infrared astronomical observations 1: Concept and performance

Applied Optics ◽

10.1364/ao.16.001834 ◽

1977 ◽

Vol 16 (7) ◽

pp. 1834 ◽

Cited By ~ 11

Author(s):

J. P. Baluteau ◽

M. Anderegg ◽

A. F. M. Moorwood ◽

N. Coron ◽

J. E. Beckman ◽

...

Keyword(s):

High Resolution ◽

Michelson Interferometer ◽

Astronomical Observations ◽

And Performance

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Design and performance of an ultra-high-resolution 300 kV microscope

Ultramicroscopy ◽

10.1016/0304-3991(96)00026-5 ◽

1996 ◽

Vol 64 (1-4) ◽

pp. 17-34 ◽

Cited By ~ 17

Author(s):

Hans Bakker ◽

Arno Bleeker ◽

Peter Mul

Keyword(s):

High Resolution ◽

And Performance

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MRA-SNet: Siamese Networks of Multiscale Residual and Attention for Change Detection in High-Resolution Remote Sensing Images

Remote Sensing ◽

10.3390/rs13224528 ◽

2021 ◽

Vol 13 (22) ◽

pp. 4528

Author(s):

Xin Yang ◽

Lei Hu ◽

Yongmei Zhang ◽

Yunqing Li

Keyword(s):

Remote Sensing ◽

High Resolution ◽

Change Detection ◽

Remote Sensing Image ◽

Image Features ◽

Remote Sensing Images ◽

The Rich ◽

The Difference ◽

Basic Network ◽

And Performance

Remote sensing image change detection (CD) is an important task in remote sensing image analysis and is essential for an accurate understanding of changes in the Earth’s surface. The technology of deep learning (DL) is becoming increasingly popular in solving CD tasks for remote sensing images. Most existing CD methods based on DL tend to use ordinary convolutional blocks to extract and compare remote sensing image features, which cannot fully extract the rich features of high-resolution (HR) remote sensing images. In addition, most of the existing methods lack robustness to pseudochange information processing. To overcome the above problems, in this article, we propose a new method, namely MRA-SNet, for CD in remote sensing images. Utilizing the UNet network as the basic network, the method uses the Siamese network to extract the features of bitemporal images in the encoder separately and perform the difference connection to better generate difference maps. Meanwhile, we replace the ordinary convolution blocks with Multi-Res blocks to extract spatial and spectral features of different scales in remote sensing images. Residual connections are used to extract additional detailed features. To better highlight the change region features and suppress the irrelevant region features, we introduced the Attention Gates module before the skip connection between the encoder and the decoder. Experimental results on a public dataset of remote sensing image CD show that our proposed method outperforms other state-of-the-art (SOTA) CD methods in terms of evaluation metrics and performance.

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