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An Autodesk Ember three-dimensional (3D) printer was used to print optical components from Clear PR48 photocurable resin. The cured PR48 was characterized by the per cent of light transmitted and the index of refraction, which was measured with a prism spectrometer. Lenses and diffraction gratings were also printed and characterized. The focal length of the printed lenses agreed with predictions based on the thin lens equation. The periodicity and effective slit width of the printed gratings were determined from both optical micrographs and fits to the Fraunhofer diffraction equation. This study aims to demonstrate the advantages offered by a layer-by-layer DLP printing process for the manufacture of optical components for use in the visible region of the electromagnetic spectrum.

A 3D printer was used to print both lenses and diffraction gratings from Standard Clear PR48 photocurable resin. The manufacturing process of the lenses and the diffraction gratings differ mainly in the printing angle with respect to the printer x-y-axes. The transmission diffraction gratings studied here were manufactured with nominal periodicities of 10, 25 and 50 µm. The aim of this study was to optically determine the effective values for the distance between slits, d, and the effective width of the slits, w, and to compare these values with the printed layer thickness.

The normalized diffraction patterns measured in this experiment for the printed gratings with layer thickness of 10, 25 and 50 µm are shown by the solid dots in Figures 8(a)-(c). Also shown as a red solid line are the fits to the experimental diffraction data. The effective values of d and w obtained from fitting the data are compared to the nominal layer thickness of the printed gratings. The effective distance between slits required to fit the diffraction patterns are well approximated by the printed layer thickness to within 14, 4 and 16 per cent for gratings with a nominal 10, 25 and 50 µm layer thickness, respectively.

Chromatic aberration is present in all polymer lenses, and the authors have not attempted to characterize it in this study. These materials could be used for achromatic lenses if paired with a crown-type material in an achromatic doublet configuration, because this would correct the chromatic aberration issues. It is worthwhile to compare the per cent transmission in cured PR48 resin (approximately 80 per cent) to the percent transmission found in common optical materials like BK7 (approximately 92 per cent) over the visible region. The authors attribute the lower transmission in PR48 to a combination of surface scattering and increased absorption. At the present time, the authors do not know what fraction of the lower transmission is related to the surface quality resulting from sample polishing.

There are inherent limitations to the 3D manufacturing process that affect the performance of lenses. Approximations to a curved surface in the design software, the printing resolution of the Autodesk Ember printer and the anisotropy due to printing in layers are believed to be the main issues. The performance of the lenses is also affected by internal imperfections in the printed material, in particular the presence of bubbles and the inclusion of debris like dust or fibers suspended in air. In addition, the absorption of wavelengths in the blue/ultraviolet produces an undesirable yellowing in any printed part.

One of the most interesting results from this study was the manufacture of diffraction gratings using 3D printing. An analysis of the diffraction pattern produced by these printed gratings yielded estimates for the slit periodicity and effective slit width. These gratings are unique because the effective slit width fills the entire volume of the printed part. This aspect makes it possible to integrate two or more optical devices in a single printed part. For example, a lens combined with a diffraction grating now becomes possible.

The paper describes a new electro‐optical board technology, based on the discrete wiring principle. Isolated copper wires are embedded in the circuit board to realise the electrical interconnections. Glass optical fibres are embedded to obtain optical interconnections. The technology allows for crossovers and for electrical and optical interconnections on one layer of interconnection. As the technology can be applied on the level of package or multichip module, circuit board and backpanel, it has the ability to offer a complete solution for chip to chip electrical and optical interconnections. The paper will describe the basic manufacturing technology of the boards. The benefits of the technology from a system designer's viewpoint will be addressed. The problem of coupling light in and out of the embedded optical fibres will be discussed and the realisation of a first on‐board optical link via embedded optical fibres will be described.

For the realization of optical waveguide components, needed for photonic integrated circuits, multimode-interference based (MMI-based) devices are an excellent component class for the realization of low loss optical splitters. A promising approach to the manufacturing of these components is their embedding in thin glass sheets by ion-exchange diffusion processes, which has not yet been extensively studied. This study aims to significantly enhance the modeling of the diffusion process to support manufacturing of graded-index, MMI-based optical splitters.

The methods of design and analysis of MMI-based components are based on a step-index refractive index profile. In this work, fundamental correlations between the properties of the manufacturing ion-exchange process and the characteristics of the graded-index, MMI-based components are established. The refractive index profile is calculated with a proprietary solver based on the finite element method. Any further investigation with respect to parameter influence is based on the beam propagation method, specifically a finite difference based, semi-vectorial, wide-angle beam propagation algorithm. The influence of the parameters of the self-imaging effect is investigated. On this basis, different approaches for efficient power splitting with graded-index, MMI-based waveguide components are evaluated.

Easy approximations – mostly linear – can be found to model the dependencies of the investigated parameters. The resulting graded-index splitters are characterized by their low excess and insertion loss.

These findings are the first step in the direction of the semi-analytical modeling of the respective waveguide components to reduce the numerical effort.

The application of laser and optical technologies in the industry is wide and extensive; the development and application of laser and optical technologies have become a promising research domain. However, most existing studies have focused on the technical aspects or the application aspects; these studies have not highlighted the technology distribution and application development of laser and optical technologies from the big picture. Additionally, the manner in which the research and development (R&D) results of universities correspond to the needs of enterprises and industry has become a topic of concern for the public. Therefore, this study aims to adopt the academic patents as the basis for analysis and to construct a laser and optical technology network.

Therefore, in the current study, the researchers have analyzed relevant academic patent technology networks, using academic patents of laser and optical technologies as a basis of analysis.

The study results indicated that the key technologies mainly lie in nanostructures, metal-working, material analysis and semiconductor devices. Additionally, these technologies are mainly applied in industries, such as optics, medical technology, pharmaceuticals, biotechnology and organic fine chemistry; this indicated that a large proportion of academia’s R&D outcomes are applied in these industries.

In this study, the researchers have constructed a technology network model to explore the technical development direction of laser and optical technologies; the results of the current study could serve as a reference for universities and industry for allocation of R&D resources.

To present work and characterisation results from a project to develop a pluggable optical connector for board to board interconnect.

An optical backplane connection system is described, which allows for repeatable docking and undocking of an active optical interface housed on a daughtercard to waveguides fabricated on an optical backplane.

The optical backplane connection system described has demonstrated its successful implementation with respect to optical data transfer across multimode polymer waveguides. Measurement results presented show that such a system is a viable approach toward the application of pluggable optical backplane interconnects.

The direct connection to the exposed waveguide interface results in considerable optical loss and scattering. Future designs will have to address this. Additional work should also be undertaken to develop a means of connector engagement that is autonomous and requires no user intervention.

Prior research into the problem of coupling to an optical backplane has been concerned with interfaces that deflect optical signals by 90° into and out of the waveguides. Here, an alternative approach is proposed that launches light directly into the waveguide ends.

This paper aims to deal with the measurement of positioning accuracies of microscale components assembled to fabricate micro-optical benches (MOB).

The concept of MOB is presented to explain how to fabricate optical MEMS based on out-of-plane micro-assembly of microcomponents. This micro-assembly platform includes a laser sensor that enables to measure the position of the microcomponent after its assembly. The measurement set-up and procedure is displayed and applied on several micro-assembly sets.

The measurement system provides results with maximum deviation smaller than ±0.005°. Based on this measurement system and micro-assembly procedure displayed in the article, it is shown that it is possible to obtain a positioning accuracy up to 0.009°.

These results clearly show that micro-assembly is a possible way to fabricate complex, heterogeneous and 3D optical MEMS with very good optical performances.

The purpose of this paper is to present the latest results from research and development into future optical printed circuit board (OPCB) interconnects and low‐cost assembly methods.

A novel method of high‐precision passive alignment and assembly to OPCBs was invented and a full evaluation platform developed to demonstrate the viability of this technique.

The technique was successfully deployed to passively align and assemble a lens receptacle onto an embedded polymer waveguide array in an electro‐OPCB. The lens receptacle formed a critical part of a dual lens pluggable in‐plane connection interface between peripheral optical devices and an OPCB. A lateral in‐plane mechanical accuracy of ±2 μm has been measured using this technique.

As this is a free space optical coupling process, surface scattering at the exposed waveguide end facet was significant.

This paper details a novel method of passively assembling arbitrary optical devices onto multi‐mode optical waveguides and outlines the procedure and equipment required. A lens coupling solution is also presented which reduces susceptibility of a connecting optical interface to contamination.

To review and explore optical fiber and carbon nanotube (CNT) as prospective alternatives to copper in VLSI interconnections.

As the technology moves to deep submicron level, the interconnect width also scales down. Increasing resistivity of copper with scaling and rising demands on current density drives the need for identifying new wiring solutions. This paper explores various alternatives to copper. Metallic CNTs, optical interconnects are promising candidates that can potentially address the challenges faced by copper.

Although, the theoretical aspects proves CNTs and optical interconnect to be better alternative against copper on the ground of performance parameters such as power dissipation, switching delay, crosstalk. But copper would last for coming decades on integration basis.

This paper reviews the state‐of‐the‐art in CNT interconnect and optical interconnect research; and discusses both the advantages and challenges of these emerging technologies.

A review of integrated optical circuit technologies [OIC] and their relevance to potential OIC sensor application. Describes the manufacture of OICs and the varied range of material technologies used. Active Silicon Integrated Optical Circuits have been developed which may have applications for many optical sensor and fibre optic sensor systems. Concludes however that silicon integrated optics will not enjoy large‐scale success until their manufacturing costs have been dramatically reduced.

The aim of the research was to evaluate the concept that utilizes structured planar substrates based on low temperature co‐fired ceramics (LTCC) as a precision platform for the passive alignment of a multimode fiber and wide‐stripe diode laser.

Presents the manufacturing process for realisation of 3D precision structures, heat dissipation structures and a cooling channel into the LTCC substrate. The developed methodology for 3D modelling and simulation of the system was used to optimize structures, materials and components in order to achieve optimal performance for the final product and still maintain reasonably low fabrication costs. The simulated optical coupling efficiency and alignment tolerances were verified by prototype realization and characterization.

The achieved passive alignment accuracy allows high coupling efficiency realisations of multimode fiber pigtailed laser modules and is suitable for mass production.

Provides guidance in the design of LTCC precision platforms for passive alignment and presents a hybrid simulation method for photonics module concept analysis.

The three‐dimensional shape of the laminated and fired ceramic substrate provides the necessary alignment structures including holes, grooves and cavities for the laser to fiber coupling. Thick‐film printing and via punching can be incorporated in order to integrate electronic assemblies directly into the opto‐mechanical platform.

Introduces the LTCC 3D precision structures for photonics modules enabling passive alignment of multimode fiber pigtailed laser with high efficiency optical coupling. Demonstrates the hybrid simulation methodology for concept analysis.