View by Category

Microsphere-assisted quantitative phase microscopy: a review
Vahid Abbasian, Tobias Pahl, Lucie Hüser, Sylvain Lecler, Paul Montgomery, et al.
Published Published online: 15 March 2024 , doi: 10.37188/lam.2024.006

Light microscopes are the most widely used devices in life and material sciences that allow the study of the interaction of light with matter at a resolution better than that of the naked eye. Conventional microscopes translate the spatial differences in the intensity of the reflected or transmitted light from an object to pixel brightness differences in the digital image. However, a phase microscope converts the spatial differences in the phase of the light from or through an object to differences in pixel brightness. Interference microscopy, a phase-based approach, has found application in various disciplines. While interferometry has brought nanometric axial resolution, the lateral resolution in quantitative phase microscopy (QPM) has still remained limited by diffraction, similar to other traditional microscopy systems. Enhancing the resolution has been the subject of intense investigation since the invention of the microscope in the 17th century. During the past decade, microsphere-assisted microscopy (MAM) has emerged as a simple and effective approach to enhance the resolution in light microscopy. MAM can be integrated with QPM for 3D label-free imaging with enhanced resolution. Here, we review the integration of microspheres with coherence scanning interference and digital holographic microscopies, discussing the associated open questions, challenges, and opportunities.

Direct laser writing on halide perovskites: from mechanisms to applications
Yuhang Sheng, Xiaoming Wen, Baohua Jia, Zhixing Gan
Published Published online: 13 March 2024 , doi: 10.37188/lam.2024.004

Metal halide perovskites have emerged as game-changing semiconductor materials in optoelectronics. As an efficient micro-/nano-manufacturing technology, direct laser writing (DLW) has been extensively used to fabricate patterns, micro/nanostructures, and pixel arrays on perovskites to promote their optoelectronic applications. Owing to the unique ionic properties and soft lattices of perovskites, DLW can introduce rich light–matter interactions, including laser ablation, crystallisation, ion migration, phase segregation, photoreaction, and other transitions, which enable diverse functionalities in addition to the intrinsic properties of perovskites. Based on their patterned structures, perovskites have numerous applications in displays, optical information encryption, solar cells, light-emitting diodes, lasers, photodetectors, and planar lenses, which are comprehensively discussed in this review. Finally, we discuss the challenges that must be addressed for the future development of this fascinating field.

Meta-device: advanced manufacturing
Borui Leng, Yao Zhang, Din Ping Tsai, Shumin Xiao
Published Published online: 07 March 2024 , doi: 10.37188/lam.2024.005

Metasurfaces are one of the most promising devices to break through the limitations of bulky optical components. By offering a new method of light manipulation based on the light-matter interaction in subwavelength nanostructures, metasurfaces enable the efficient manipulation of the amplitude, phase, polarization, and frequency of light and derive a series of possibilities for important applications. However, one key challenge for the realization of applications for meta-devices is how to fabricate large-scale, uniform nanostructures with high resolution. In this review, we review the state-of-the-art nanofabrication techniques compatible with the manufacture of meta-devices. Maskless lithography, masked lithography, and other nanofabrication techniques are highlighted in detail. We also delve into the constraints and limitations of the current fabrication methods while providing some insights on solutions to overcome these challenges for advanced nanophotonic applications.

Imaging/nonimaging microoptical elements and stereoscopic systems based on femtosecond laser direct writing
Long Huang, Zhihan Hong, Qi-Dai Chen, Yong-Lai Zhang, Shaoqing Zhao, et al.
Published Published online: 31 October 2023 , doi: 10.37188/lam.2023.037

The development of modern information technology has led to significant demand for microoptical elements with complex surface profiles and nanoscale surface roughness. Therefore, various micro- and nanoprocessing techniques are used to fabricate microoptical elements and systems. Femtosecond laser direct writing (FsLDW) uses ultrafast pulses and the ultraintense instantaneous energy of a femtosecond laser for micro-nano fabrication. FsLDW exhibits various excellent properties, including nonlinear multiphoton absorption, high-precision processing beyond the diffraction limit, and the universality of processable materials, demonstrating its unique advantages and potential applications in three-dimensional (3D) micro-nano manufacturing. FsLDW has demonstrated its value in the fabrication of various microoptical systems. This study details three typical principles of FsLDW, several design considerations to improve processing performance, processable materials, imaging/nonimaging microoptical elements, and their stereoscopic systems. Finally, a summary and perspective on the future research directions for FsLDW-enabled microoptical elements and stereoscopic systems are provided.

Recent progress on micro-LEDs
Ayush Pandey, Maddaka Reddeppa, Zetian Mi
Published Published online: 06 December 2023 , doi: 10.37188/lam.2023.031

With the advent of technologies such as augmented/virtual reality (AR/VR) that are moving towards displays with high efficiency, small size, and ultrahigh resolution, the development of optoelectronic devices with scales on the order of a few microns or even smaller has attracted considerable interest. In this review article we provide an overview of some of the recent developments of visible micron-scale light emitting diodes (LEDs). The major challenges of higher surface recombination for smaller size devices, the difficulty in attaining longer emission wavelengths, and the complexity of integrating individual, full color devices into a display are discussed, along with techniques developed to address them. We then present recent work on bottom-up nanostructure-based sub-micron LEDs, highlighting their unique advantages, recent developments, and promising potential. Finally, we present perspectives for future development of micro-LEDs for higher efficiencies, better color output and more efficient integration.

Two-photon lithography for integrated photonic packaging
Shaoliang Yu, Qingyang Du, Cleber Renato Mendonca, Luigi Ranno, Tian Gu, et al.
Published Published online: 01 November 2023 , doi: 10.37188/lam.2023.032

Photonic integrated circuits (PICs) have long been considered as disruptive platforms that revolutionize optics. Building on the mature industrial foundry infrastructure for electronic integrated circuit fabrication, the manufacturing of PICs has made remarkable progress. However, the packaging of PICs has often become a major barrier impeding their scalable deployment owing to their tight optical alignment tolerance, and hence, the requirement for specialty packaging instruments. Two-photon lithography (TPL), a laser direct-write three-dimensional (3-D) patterning technique with deep subwavelength resolution, has emerged as a promising solution for integrated photonics packaging. This study provides an overview of the technology, emphasizing the latest advances in TPL-enabled packaging schemes and their prospects for adoption in the mainstream photonic industry.

Hybrid-integrated chalcogenide photonics
Bin Zhang, Di Xia, Xin Zhao, Lei Wan, Zhaohui Li
Published Published online: 22 September 2023 , doi: 10.37188/lam.2023.024

High-quality photonic materials are critical for promoting integrated photonic devices with broad bandwidths, high efficiencies, and flexibilities for high-volume chip-scale fabrication. Recently, we designed a home-developed chalcogenide glass (ChG)-Ge25Sb10S65 (GeSbS) for optical information processing chips and systems, which featured an ultrabroad transmission window, a high Kerr nonlinearity and photoelastic coefficient, and compatibility with the photonic hybrid integration technology of silicon photonics. Chip-integrated GeSbS microresonators and microresonator arrays with high quality factors and lithographically controlled fine structures were fabricated using a modified nanofabrication process. Moreover, considering the high Kerr nonlinearity and photoelastic effect of ChGs, we realised a novel ChG hybrid integrated chip, inspired by recent advances in integrated soliton microcombs and acousto-optic (AO) modulators.

Hybrid integration of 2D materials for on-chip nonlinear photonics
Vincent Pelgrin, Hoon Hahn Yoon, Eric Cassan, Zhipei Sun
Published Published online: 01 August 2023 , doi: 10.37188/lam.2023.014

Interests surrounding the development of on-chip nonlinear optical devices have been consistently growing in the past decades due to the tremendous applications, such as quantum photonics, all-optical communications, optical computing, on-chip metrology, and sensing. Developing efficient on-chip nonlinear optical devices to meet the requirements of those applications brings the need for new directions to improve the existing photonic approaches. Recent research has directed the field of on-chip nonlinear optics toward the hybrid integration of two-dimensional layered materials (such as graphene, transition metal dichalcogenides, and black phosphorous) with various integrated platforms. The combination of well-known photonic chip design platforms (e.g., silicon, silicon nitride) and different two-dimensional layered materials has opened the road for more versatile and efficient structures and devices, which has the great potential to unlock numerous new possibilities. This review discusses the modeling and characterization of different hybrid photonic integration structures with two-dimensional materials, highlights the current state of the art examples, and presents an outlook for future prospects.

Measurement techniques for aspheric surface parameters
Qun Hao, Yiming Liu, Yao Hu, Xin Tao
Published Published online: 28 July 2023 , doi: 10.37188/lam.2023.019

Aspheric surfaces are widely used in advanced optical instruments. Measuring the aspheric surface parameters (ASPs) with high accuracy is vital for manufacturing and aligning optical aspheric surfaces. This paper provides a review of various techniques for measuring ASPs and discusses the advantages/disadvantages of these approaches. The aim of this review is to contribute to advancements in the fabrication and testing of aspheric optical elements and their practical applications in diverse fields.

Perovskite light-emitting diodes toward commercial full-colour displays: progress and key technical obstacles
Changjiu Sun, Yuanzhi Jiang, Keyu Wei, Mingjian Yuan
Published Published online: 13 July 2023 , doi: 10.37188/lam.2023.015

Metal-halide perovskite light-emitting diodes (PeLEDs) possess wide colour gamut, high luminescence efficiency, and low-cost synthesis, making them a promising photonic source for next-generation display applications. Since the first room-temperature emission PeLED was demonstrated in 2014, their performance has improved rapidly within a few years, leading to considerable attention from academia and industry. In this review, we discuss the primary technical bottlenecks of PeLEDs for commercial display applications, including large-area PeLED preparation, patterning strategies, and flexible PeLED devices. We review the technical approaches for achieving these targets and highlight the current challenges while providing an outlook for these perovskite materials and PeLED devices to meet the requirements of the next-generation high-colour-purity full-colour display market.

  • First
  • Prev
  • 1
  • 2
  • 3
  • 4
  • 5
  • Last
  • Total:5
  • To
  • Go