scholarly journals Noncontact Microembossing Technology for Fabricating Thermoplastic Optical Polymer Microlens Array Sheets

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Xuefeng Chang ◽  
Dan Xie ◽  
Xiaohong Ge ◽  
Hui Li
Keyword(s):  
Mechanical Characteristics ◽  
Optical Glass ◽  
Low Cost ◽  
Microlens Array ◽  
Production Costs ◽  
Efficient Production ◽  
Promising Technique ◽  
Element Analysis ◽  
Microlens Arrays ◽  
Optical Polymer

Thermoplastic optical polymers have replaced traditional optical glass for many applications, due to their superior optical performance, mechanical characteristics, low cost, and efficient production process. This paper investigates noncontact microembossing technology used for producing microlens arrays made out of PMMA (polymethyl methacrylate), PS (polyStyrene), and PC (polycarbonate) from a quartz mold, with microhole arrays. An array of planoconvex microlenses are formed because of surface tension caused by applying pressure to the edge of a hole at a certain glass transition temperature. We studied the principle of noncontact microembossing techniques using finite element analysis, in addition to the thermal and mechanical properties of the three polymers. Then, the independently developed hot-embossing equipment was used to fabricate microlens arrays on PMMA, PS, and PC sheets. This is a promising technique for fabricating diverse thermoplastic optical polymer microlens array sheets, with a simple technological process and low production costs.

scholarly journals Fabrication of Multiscale-Structure Wafer-Level Microlens Array Mold

2019 ◽  
Vol 9 (3) ◽  
pp. 487 ◽  
Author(s):  
Shuping Xie ◽  
Xinjun Wan ◽  
Xiaoxiao Wei
Keyword(s):  
Low Cost ◽  
Form Factors ◽  
Cost Effective ◽  
Microlens Array ◽  
Practical Method ◽  
Reduced Form ◽  
Wafer Level ◽  
Polycrystalline Aluminum ◽  
Microlens Arrays ◽  
Multiscale Structure

The design and manufacture of cost-effective miniaturized optics at wafer level, usingadvanced semiconductor-like techniques, enables the production of reduced form-factor cameramodules for optical devices. However, suppressing the Fresnel reflection of wafer-level microlensesis a major challenge. Moth-eye nanostructures not only satisfy the antireflection requirementof microlens arrays, but also overcome the problem of coating fracture. This novel fabricationprocess, based on a precision wafer-level microlens array mold, is designed to meet the demandfor small form factors, high resolution, and cost effectiveness. In this study, three different kinds ofaluminum material, namely 6061-T6 aluminum alloy, high-purity polycrystalline aluminum, and purenanocrystalline aluminum were used to fabricate microlens array molds with uniform nanostructures.Of these three materials, the pure nanocrystalline aluminum microlens array mold exhibited auniform nanostructure and met the optical requirements. This study lays a solid foundation for theindustrial acceptation of novel and functional multiscale-structure wafer-level microlens arrays andprovides a practical method for the low-cost manufacture of large, high-quality wafer-level molds.

A Microlens Array with Different Focal Lengths Fabricated by Roll-To-Roll UV Lithography

2018 ◽  
Vol 26 (2) ◽  
pp. 155-159
Author(s):  
Huichun Ye ◽  
Lianguan Shen ◽  
Mujun Li ◽  
Likai Li
Keyword(s):  
Optical Properties ◽  
Low Cost ◽  
Microlens Array ◽  
Master Mold ◽  
Pdms Mold ◽  
Microlens Arrays ◽  
Array Pattern ◽  
Roll To Roll ◽  
Ultra Precision ◽  
Micro Structures

A simple, highly efficient and low cost roll-to-roll (R2R) UV imprinting lithography facility was achieved for fabricating micro-structures. Firstly, a novel microlens array with focuses distributed on a curved surface was designed and analyzed by an optical software ZEMAX. Then an ultra-precision diamond machine was applied to generate the freeform microlens array features on the master mold, and a belt-type polydimethylsiloxane (PDMS) mold with a microlens array pattern was prepared from the machined master mold. The R2R process was employed to replicate the microlens arrays, followed by an evaluation of their profiles and optical properties. Our experiments demonstrate that the applied method is reliable and efficient for producing the polymeric microlens arrays.

scholarly journals Mechanical Behaviour of E -Glass and Aluminium Hybrid Composite

2021 ◽  
Vol 23 (05) ◽  
pp. 164-171
Author(s):  
Saroj Kumar ◽  
◽  
Keshav Kumar Jha ◽  
Keyword(s):  
Hybrid Composite ◽  
Hybrid Composites ◽  
Low Cost ◽  
Production Costs ◽  
Service Needs ◽  
Matrix Composites ◽  
Mass Ratio ◽  
Element Analysis ◽  
The Subject ◽  
Ansys Workbench

The mechanical behavior of the E-Glass and Aluminum Hybrid composite is the subject of this research. A large number of writings has been referred in this regard, and it takes been discovered that dispensation circumstances dismiss remain adjusted to obtain Al-composites construction. E GLASS and Aluminum mixture composites remain a modern group of the metal matrix composites with an ability to meet the needs of specialized manufacturing submissions. Aluminum mixture strengthening technology is a solution to the diverse and the ever-increasing service needs of an industries such by way of aviation, aerospace, automobiles, and a maritime, among others. These requirements are fulfilled thanks to better mechanical properties, the ability to manufacture aluminum hybrid composites using traditional methods, and the prospect of lowering production costs. Meanwhile of the manufacturing constraints are linked to the strengthening particulates, the efficiency of these products is largely reliant on choosing the correct mix of reinforcing materials. The results of this study show that E-Glass and Al-based hybrid composites have a lot of potential as a replacement for earthenware reinforced compounds and unreinforced Al-alloys in a variety of locomotive submissions that require low cost, in height strength-to-mass ratio, and greater dress confrontation. Finite element analysis was used to perform mechanical possessions such as tensile and impact tests (Ansys workbench 19.2).

scholarly journals Fabrication and Optical Characterization of Polymeric Aspherical Microlens Array Using Hot Embossing Technology

2021 ◽  
Vol 11 (2) ◽  
pp. 882
Author(s):  
Yanlong Li ◽  
Kangsen Li ◽  
Feng Gong
Keyword(s):  
Process Parameters ◽  
High Efficiency ◽  
Low Cost ◽  
Microlens Array ◽  
Hot Embossing ◽  
Molding Pressure ◽  
Microlens Arrays ◽  
Aspheric Lens ◽  
Molding Temperature ◽  
Holding Temperature

Hot embossing has been widely used in fabricating microlens arrays because of its low cost, high efficiency, and high quality. The process parameters such as molding temperature, molding pressure, and holding temperature affect the microlens array’s replication quality. This work selected the stainless steel S136H tool steel as the mold material to process an aspheric microlens array structure through ultra-precision milling. Polymethyl methacrylate (PMMA) microlens arrays with different surface replication were prepared by controlling the molding temperature, molding pressure, and holding temperature. By analyzing the surface quality, contour replication, and optical imaging of hot-embossed samples, the optimal molding temperature of PMMA for optimal replication of aspheric lens arrays was determined as 130 °C. Besides, the internal elastic recovery of PMMA affected the dimensional accuracy and optical performance of the lens. The results showed that, at the molding pressure of 400 N and the holding temperature of 60 °C, the surface defects were eliminated, and the aspheric lens array had perfect replication with a profile deviation of only 4 μm. The aspheric microlens array with good quality was eventually achieved by these optimal process parameters, which provides a foundation for producing aspheric microlens arrays in a low-cost and high-efficiency way.

scholarly journals Hydrogen production from water electrolysis: role of catalysts

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Shan Wang ◽  
Aolin Lu ◽  
Chuan-Jian Zhong
Keyword(s):  
Hydrogen Production ◽  
Water Splitting ◽  
Noble Metal ◽  
Active Sites ◽  
Current Knowledge ◽  
Low Cost ◽  
Critical Role ◽  
Water Electrolysis ◽  
Efficient Production ◽  
Production Of Hydrogen

AbstractAs a promising substitute for fossil fuels, hydrogen has emerged as a clean and renewable energy. A key challenge is the efficient production of hydrogen to meet the commercial-scale demand of hydrogen. Water splitting electrolysis is a promising pathway to achieve the efficient hydrogen production in terms of energy conversion and storage in which catalysis or electrocatalysis plays a critical role. The development of active, stable, and low-cost catalysts or electrocatalysts is an essential prerequisite for achieving the desired electrocatalytic hydrogen production from water splitting for practical use, which constitutes the central focus of this review. It will start with an introduction of the water splitting performance evaluation of various electrocatalysts in terms of activity, stability, and efficiency. This will be followed by outlining current knowledge on the two half-cell reactions, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), in terms of reaction mechanisms in alkaline and acidic media. Recent advances in the design and preparation of nanostructured noble-metal and non-noble metal-based electrocatalysts will be discussed. New strategies and insights in exploring the synergistic structure, morphology, composition, and active sites of the nanostructured electrocatalysts for increasing the electrocatalytic activity and stability in HER and OER will be highlighted. Finally, future challenges and perspectives in the design of active and robust electrocatalysts for HER and OER towards efficient production of hydrogen from water splitting electrolysis will also be outlined.

scholarly journals Extraction of short chain chitooligosaccharides from fungal biomass and their use as promoters of arbuscular mycorrhizal symbiosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Andrea Crosino ◽  
Elisa Moscato ◽  
Marco Blangetti ◽  
Gennaro Carotenuto ◽  
Federica Spina ◽  
...  
Keyword(s):  
Fungal Biomass ◽  
Large Scale ◽  
Low Cost ◽  
Trichoderma Viride ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Production Costs ◽  
Short Chain ◽  
Mycorrhizal Symbiosis ◽  
Major Interest

AbstractShort chain chitooligosaccharides (COs) are chitin derivative molecules involved in plant-fungus signaling during arbuscular mycorrhizal (AM) interactions. In host plants, COs activate a symbiotic signalling pathway that regulates AM-related gene expression. Furthermore, exogenous CO application was shown to promote AM establishment, with a major interest for agricultural applications of AM fungi as biofertilizers. Currently, the main source of commercial COs is from the shrimp processing industry, but purification costs and environmental concerns limit the convenience of this approach. In an attempt to find a low cost and low impact alternative, this work aimed to isolate, characterize and test the bioactivity of COs from selected strains of phylogenetically distant filamentous fungi: Pleurotus ostreatus, Cunninghamella bertholletiae and Trichoderma viride. Our optimized protocol successfully isolated short chain COs from lyophilized fungal biomass. Fungal COs were more acetylated and displayed a higher biological activity compared to shrimp-derived COs, a feature that—alongside low production costs—opens promising perspectives for the large scale use of COs in agriculture.

scholarly journals Properties of Low-Cost WPCs Made from Alien Invasive Trees and rLDPE for Interior Use in Social Housing

Polymers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2436
Author(s):  
Abubakar Sadiq Mohammed ◽  
Martina Meincken
Keyword(s):  
Tensile Strength ◽  
Water Absorption ◽  
Social Housing ◽  
Low Cost ◽  
Production Costs ◽  
Low Density Polyethylene ◽  
Low Grade ◽  
Low Density ◽  
Invasive Trees ◽  
Recycled Low Density Polyethylene

Low-cost wood–plastic composites (WPCs) were developed from invasive trees and recycled low-density polyethylene. The aim was to produce affordable building materials for low-cost social housing in South Africa. Both raw materials are regarded as waste materials, and the subsequent product development adds value to the resources, while simultaneously reducing the waste stream. The production costs were minimised by utilising the entire biomass of Acacia saligna salvaged from clearing operations without any prior processing, and low-grade recycled low-density polyethylene to make WPCs without any additives. Different biomass/plastic ratios, particle sizes, and press settings were evaluated to determine the optimum processing parameters to obtain WPCs with adequate properties. The water absorption, dimensional stability, modulus of rupture, modulus of elasticity, tensile strength, and tensile moduli were improved at longer press times and higher temperatures for all blending ratios. This has been attributed to the crystallisation of the lignocellulose and thermally induced cross-linking in the polyethylene. An increased biomass ratio and particle size were positively correlated with water absorption and thickness swelling and inversely related with MOR, tensile strength, and density due to an incomplete encapsulation of the biomass by the plastic matrix. This study demonstrates the feasibility of utilising low-grade recycled polyethylene and the whole-tree biomass of A. saligna, without the need for pre-processing and the addition of expensive modifiers, to produce WPCs with properties that satisfy the minimum requirements for interior cladding or ceiling material.

scholarly journals Effect on the enzymatic hydrolysis of lipids from dairy wastewater by replacing Gum Arabic emulsifier for sodium chloride

2005 ◽  
Vol 48 (spe) ◽  
pp. 135-142 ◽  
Author(s):  
Adriano Aguiar Mendes ◽  
Heizir Ferreira de Castro
Keyword(s):  
Sodium Chloride ◽  
Enzymatic Hydrolysis ◽  
Suspended Solids ◽  
Lower Cost ◽  
Low Cost ◽  
Gum Arabic ◽  
Dairy Wastewater ◽  
Promising Technique ◽  
Animal Source ◽  
Hydrolysis Of

The objective of this work was to evaluate the replacement of Gum Arabic for sodium chloride to reduce fat and organic contents in dairy wastewater using two low cost commercially available lipase preparations from animal source (Kin Master - LKM and Nuclear- LNU). The best performance was achieved when lipase Nuclear (LNU) was used as catalyst. In addition, this lipase preparation has also lower cost, which makes its use a quite promising technique for reduction of suspended solids as proteins and lipids contents found in wastewater generated by dairy industries.

Weight-Reduction Optimization Design for Milling Planer Bed Based on Finite Element Analysis

2012 ◽  
Vol 490-495 ◽  
pp. 2785-2789
Author(s):  
Dong Sun ◽  
Xu Dong Yang
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Weight Reduction ◽  
Optimization Design ◽  
Weak Link ◽  
Three Dimensional ◽  
Production Costs ◽  
Element Analysis ◽  
Before And After ◽  
Improvement Scheme

The milling planer bed is one of the most important foundational parts for the entire machine, sufficient stiffness is required. The posterior segment of a certain milling planer bed is regarded as the optimization object in this paper. Three-dimensional modeling method is used to calculate the exact weight of the bed and then finite element analysis is used to research the static and dynamic characteristics before and after weight-reduction. The weak link of the bed is found out and a improvement scheme is put forward ensuring lower production costs under the premise of sufficient rigidity.

Performance of Low-Cost 3D Printer in Medical Application

2021 ◽  
Author(s):  
Nor Aiman Sukindar ◽  
Azib Azhari Awang Dahan ◽  
Sharifah Imihezri Syed Shaharuddin ◽  
Nor Farah Huda Abd Halim
Keyword(s):  
Low Cost ◽  
Medical Application ◽  
Fused Deposition Modelling ◽  
3D Printer ◽  
Layer By Layer ◽  
Total Deformation ◽  
Element Analysis ◽  
Porosity Level ◽  
Fused Deposition ◽  
Printing Parameters

Abstract Fused Deposition Modelling (FDM) is an additive manufacturing (AM) process that produces a physical object directly from a CAD design using layer-by-layer deposition of the filament material that is extruded via a nozzle. In industry, FDM has become one of the most used AM processes for the production of low batch quantity and functional prototypes, due to its safety, efficiency, reliability, low cost, and ability to process manufacturing-grade engineering thermoplastic. Recently, the market is flooded with the availability of low-cost printers produced by numerous companies. This research aims to investigate the effect of different porosity levels on a scaffold structure produced using a low-cost 3D printer. Comparisons of these porous structures were made in terms of Von-Mises strain, total deformation, as well as compressive stress. Various porosity levels were created by varying printing parameters, including layer height, infill density, and shell thickness by slicing the initial solid CAD file using Repetier Host 3D printing software. Finite Element Analysis (FEA) simulation was then performed on the created scaffold structures by using Ansys Workbench 19.2. The simulation result indicates that the greater porosity level will result in higher total deformation of the structure. Meanwhile, the compression test shows that the minimum strength value obtained was favourable at 22 MPa and had exceeded that of the trabecular femur (15 MPa). However, its porosity level (maximum at 52%) was still below that of the minimum threshold of porosity level of 70 percent. However, the printing parameters currently used can be adjusted in the future. Therefore, it was deduced that the low-cost 3D printer offers promising potential to fabricate different porosity structures with multiple outcomes.

Sign in / Sign up

Export Citation Format

Share Document