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It is a huge technical and engineering challenge to realize the precise assembly of thousands of large optics in high power solid-state laser system. Using the 400-mm aperture-sized transport mirror as a case, this paper aims to present an intelligent numerical computation methodology for mounting performance analysis and modeling of large optics in a high-power laser system for inertial confinement fusion (ICF).

Fundamental principles of modeling and analysis of the transport mirror surface distortion are proposed, and a genetic algorithm-based computation framework is proposed to evaluate and optimize the assembly and mounting performance of large laser optics.

The stringent specifications of large ICF optics place very tight constraints upon the transport mirror’s assembly and mounts. The operational requirements on surface distortion [peak-to-valley and root mean square (RMS)] can be met as it is appropriately assembled by the close loop of assembly-inspection-optimization-fastening. In the end, the experimental study validates the reliability and effectiveness of the transport mirror mounting method.

In the assembly design and mounting performance evaluation of large laser optics, the whole study has the advantages of accurate evaluation and intelligent optimization on nano-level optical surface distortion, which provides a fundamental methodology for precise assembly and mounting of large ICF optics.

Traditional ion optics manufacturing processes are complex and costly. The purpose of this paper is to study the feasibility of using selective laser melting (SLM) to produce additively manufactured ion optics.

An SLM machine was used to generate Ti6Al4V screen grids. The output was separated through wire cutting from the build platform and studied through a scanning electron microscope. To increase the geometrical accuracy of the original grid, samples consisting of nine-aperture arrays were fabricated with different parameter combinations, increasing the energy density. An empirical method to correlate the energy density applied in the fabrication process with the dimensional accuracy of the hole array positioning was developed through the analysis of multiple samples.

The SLM machine generated grids with optimal microstructure, the apertures fell within the specified tolerances and tolerances of slightly less than 10 µm can be guaranteed for the hole array positioning. The grids’ upper surfaces presented good-quality surface finish, and the lower surface quality was acceptable when the wire cutting process that separated the grid from the build platform performed slowly. Regardless of the build strategy, the stresses generated in the separation process caused the warping of the ion optic, so a flattening operation was necessary in all cases.

This research proved that SLM is a viable solution for ion optics fabrication, faster (less than 24 h) and less expensive (order of US$300) than traditional fabrication methods (with fabrication times from 24 to more than 400 h and costs from US$500 to US$5,000, depending on the material, size and shape).

Fiber optics has the capability to dramatically increase telecommunications capability and lower costs. This article examines fiber optic technology, explains some of the key terminology, and speculates about the way fiber optics will change our world.

The purpose of this paper is to compare exact and Physical‐Optics‐approximated results of the electromagnetic field scattered by a perfectly conducting semi‐infinite elliptic cone illuminated by a plane wave. The results are important for judging the reliability of Physical‐Optics based field estimations of electrically large environments which include tip‐like structures (e.g. airport scenarios).

The spherical‐multipole analysis is applied to determine the exact total field outside a perfectly conducting semi‐infinite elliptic cone. The underlying boundary‐value problem is solved by a separation of variables of the Helmholtz equation in sphero‐conal coordinates leading to a two‐parametric eigenvalue problem with two coupled Lamé differential equations. The exact scattered far field is determined from the exact surface current on the cone using a bilinear expansion of the dyadic Green's function. The Physical‐Optics (PO) field is evaluated similarly starting from a surface current which is directly found from the incident magnetic field.

The diffraction coefficients of the exact scattered field and the PO scattered field are compared for different parameters (polarization and angle of incidence) of the plane wave. Reasonably well corresponding results are obtained for those angles of incidence of the plane wave where the entire cone is illuminated, otherwise the error of the PO approximation is increasing not just in the shadow region.

If carefully applied, the Physical‐Optics method can be useful and sufficient to obtain fields scattered by cone‐like structures.

ONE of the reasons why the aircraft industry has made prodigious achievements during the last years is because it has always been quick to realise the potential of a new design concept or production technique.

The effects which are produced by pearlescent pigments are intimately connected to optics and the interaction of light with matter. Pearlescent pigments are optical filters which reflect and transmit light which falls upon them. In order to understand pearlescent pigments, therefore it is first necessary to understand some of the basic laws of optics. I would like to review some of these laws to talk about light and its interaction with matter, how it can be separated into its components, the laws of reflection and refraction and how all of these laws apply to pearlescent pigments.

Electronics manufacturing throughout the world now uses an increasing percentage of Surface Mount Technology (SMT). The compact and light‐weight surface‐mounted components offer a number of advantages to manufacturers. Unfortunately, however, these same beneficial characteristics make the quality of the product difficult to guarantee. As miniaturisation continues, the inspection problem becomes worse, and so advanced methods of inspection are required. Automatic inspection systems already exist, although an effective, inexpensive and reliable system has yet to be found. Recent work carried out within the Coherent and Electro‐Optics Research Group at Liverpool Polytechnic has looked at the feasibility of applying some of its established inspection methods to the problem of solder joint inspection. Extensive development must still take place; however, the methods employed have shown promise. The system uses structured light techniques to add height information to an image of the solder joint under inspection. In this way a 3‐D image of the joint may be built up, digitised and processed in a computer at high speed in order to determine its quality.

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.

FIBRE OPTICS — the science of ‘bending’ light — may well have a revolutionary effect on many aspects of airports in the next few years.