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Lenses are used to mount on the light-emitting diode (LED) chip to obtain the desired light distribution patterns. In this study, a lens for large viewing angle and high uniformity LED has ...

Injection molding technology is known as the most widely used method in mass production of plastic products. To meet the quality requirements, a lot of methods were applied in optimization of injection molding process parameter. In this study the optimization based on Taguchi orthogonal array and Grey relational analysis (GRA) is used to optimize the injection molding process parameters on a LED lens. The four process parameters are: packing pressure, injection speed, melt temperature and mold temperature. The multi-response quality characteristics are total displacement, volumetric shrinkage, and thermal residual stress. The optimal molding parameters are packing pressure (90 MPa), injection speed (300 mm/sec), melt temperature (270 °C) and mold temperature (90 °C). The luminous uniformity of the LED is 92.61 % and the viewing angle of the LED is 124.76°. Among the four factors, packing pressure plays the key role in reducing total displacement, volumetric shrinkage, and thermal residual stress.

ZnO/Mo/ZnO transparent conductive thin films are deposited on Corning glass substrates using an RF magnetron sputtering system. The optical and electrical properties of the thin films are then examined following annealing for 40 min at temperatures ranging from 200 to 450 °C. It is shown that the resistivity of the ZnO/Mo/ZnO films has a low and reducing value at annealing temperatures up to 300 °C. However, the resistivity increases dramatically as the annealing temperature is further increased to 450 °C. The average transmittance of the annealed films generally increases with an increasing annealing temperature as the result of a larger grain size. For an annealing temperature of 450 °C, the maximum transmittance is equal to approximately 85%. Overall, the results suggest that the optimal annealing temperature for the present ZnO/Mo/ZnO films is 300 °C, which results in an electrical resistivity of 6.44 × 10−3 Ω-cm and an optical transmittance of 80%.

Micro molding is a rapid and cost-effective micro manufacturing technology. However, during the manufacturing process, different kinds of products usually face problems with uneven thicknesses or particular structure designs, resulting in uneven products shrinkage. This research focuses on exploring the problems of molding a micro part with biconcave structure and sharp edges. Using the Taguchi Experimental Method, it aims to find the critical molding parameters which influence the moldability of the micro part, as well as to minimize the shrinking of part. This study used polypropylene (PP) for the injection molding and successfully resolved the void defect which appeared in the center of this biconcave structure. Melt temperature contributed the highest percentage (41.235%) to the shrinkage, followed by injection speed (31.947%) and mold temperature (12.887%). The optimal process parameters for injection molding obtained from the experiment which are melt temperature 240oC mold temperature 90oC, and injection speed of 30 mm/s and the shrinkage rate is 1.641%.

In this paper, it utilizes co-sputtering method to deposit MGZO transparent conductive thin film on a corning glass substrate. Furthermore, it also investigated the effect of annealing temperature on the optoelectrical properties and surface structural of MGZO transparent conductive film. The results show MGZO transparent conductive film can obtain the lowest resistivity of 7.57 × 10−3 Ω-cm on the sputtering power 90 W, 4 mtorr bias and at the annealing temperature of 300 °C. Furthermore, the best transmittance is 81% at the annealing temperature of 300 °C. Finally, the grain size also increases with increasing annealing temperature.

The Blu-ray objective lens is one of the electronic parts that has an important role in data storage in such a way that its production requires a high level of accuracy. One way to produce the Blu-ray objective lens is by means of a micro-injection molding technique. We investigated the effect of insert part in a multi-shot injection molding on the shrinkage after the process of injection. An aspherical shape is made for the insert part of the Blu-ray objective lens, then compared with single-shot injection molding. Zemax software was used to design the Blu-ray objective lens, while Moldex3D software was applied to analyze the flow of material into the mold during the injection process. The Taguchi method was used to determine the best parameters to obtain the minimum shrinkage values of the injection processes of both multi-shot injection and single-shot injection molding techniques. Based on the observations, it is clearly evident that the multi-shot injection molding process has a lower displacement value compared to the single-shot injection molding, namely, 0.0161 mm compared to 0.0550 mm and also the multi-shot injection can save the cooling time 5 seconds faster than single-shot injection molding. So, this can favorably improve the production of the injection process for the material in the form of the micro part.

Magnesium alloys have recently been attracting attention as a degradable biomaterial. They have advantages including non-toxicity, biocompatibility, and biodegradability. To develop magnesium alloys into biodegradable medical materials, previous research has quantitatively analyzed magnesium alloy corrosion by focusing on the overall changes in the alloy. Therefore, the objective of this study is to develop a bioactive material by applying a ceramic oxide coating (magnesia) on AZ31 magnesium alloy through micro-arc oxidation (MAO) process. This MAO process is conducted under pulsed bipolar constant current conditions in a Si- and P-containing electrolyte and the optimal processing parameters in corrosion protection are obtained by the Taguchi method to design a coating with good anti-corrosion performance. The negative duty cycle and treatment time are two deciding factors of the coating&rsquo, s capability in corrosion protection. Microstructure characterizations are investigated by means of SEM and XRD. The simulation body-fluid solution is utilized for testing the corrosion resistance with the potentiodynamic polarization and the electrochemical impedance test data. Finally, an in vivo testing shows that the MAO-coated AZ31 has good cytocompatibility and anticorrosive properties.

Micro arc oxidation (MAO) is a prominent surface treatment to form bioceramic coating layers with beneficial physical, chemical, and biological properties on the metal substrates for biomaterial applications. In this study, MAO treatment has been performed to modify the surface characteristics of AZ31 Mg alloy to enhance the biocompatibility and corrosion resistance for implant applications by using an electrolytic mixture of Ca3(PO4)2 and C10H16N2O8 (EDTA) in the solutions. For this purpose, the calcium phosphate (Ca-P) containing thin film was successfully fabricated on the surface of the implant material. After in-vivo implantation into the rabbit bone for four weeks, the apparent growth of soft tissues and bone healing effects have been documented. The morphology, microstructure, chemical composition, and phase structures of the coating were identified by SEM, XPS, and XRD. The corrosion resistance of the coating was analyzed by polarization and salt spray test. The coatings consist of Ca-P compounds continuously have proliferation activity and show better corrosion resistance and lower roughness in comparison to mere MAO coated AZ31. The corrosion current density decreased to approximately 2.81 × 10−7 A/cm2 and roughness was reduced to 0.622 μm. Thus, based on the results, it was anticipated that the development of degradable materials and implants would be feasible using this method. This study aims to fabricate MAO coatings for orthopedic magnesium implants that can enhance bioactivity, biocompatibility, and prevent additional surgery and implant-related infections to be used in clinical applications.

The influence of In 3+ doping on the binding energy of ions and the energy transfer mechanism of white SrZn 2 (PO 4 ) 2 :Eu 2+ ,Mn 2+ phosphor was investigated. The ligand fields around Sr 2+ and Mn 2+ varied with different kinds of doped ions, while those around Zn 2+ and Eu 2+ remained stable. Doping with In 3+ created traps of charged species and clustered pairs in the phosphor. These traps captured excited carriers, leading to a decrease in energy transfer from Eu 2+ to Mn 2+ and a decline in Mn 2+ emission. However, carriers stored temporarily in traps then migrated to Eu 2+ to yield an enhanced Eu 2+ emission. The phosphor emission was blue-shifted by the increase in In 3+ concentration. Maximum Eu 2+ energy absorption and emission were obtained when doped with 12 mol% of In 3+ . The decay time of the phosphor was 11.74 ms.

This study integrated plasticizing screw analysis software with neural-network in the design of a screw for injection molding application. The qualities of the plasticizing screw selected in this study are output rate, melt temperature variation at the end of metering zone, the specific mechanical energy (SME), and the melting distance. The Taguchi orthogonal array is implemented to carry out the experiment and to obtain the test data for training the neural network. The Back-propagation Neural Network (BPNN) was then used for screw quality predictor, and optimal design was solved with Genetic Algorithm (GA). The optimal screw design for a diameter of 25 mm screw for molding PC resin in this study is 5.37D in solid conveying zone, 9D in compression zone, metering zone depth of 2.44 mm, and flight width of 3 mm. The performance of this screw with the preset processing condition can have the temperature difference at the end of metering (ΔT) of 5.67°C, the output rate Q of 20.12 kg/h, the SME of 520.80 (kJ/kg), and the plastics completely melted at 17.39D.

In this work, pH-sensitive chitosan (CTS)-g-polyvinyl acetate (PVAc) copolymer was used to self-reduce Pd nanoparticles (PdNPs). By heating the aqueous solution in the presence of metal ions and CTS-g-PVAc, the metal nuclei reduced within the core. Since the amino group in chitosan has a pKa value of ~ 6.5, thus, chitosan is positively charged (NH 3 + ) in acidic or neutral solution, whereas it turns to neutral in an alkaline solution. The pH-sensitive CTS chains not only function as stabilizing agent for noble metal nanoparticles in ink solution but also enhance the adhesion between PdNPs and substrate during the electroless deposition of Cu lines. Therefore, the Cu line with dramatically enhanced adhesion is formed on the surface of indium tin oxide (ITO) glass substrate without special pretreatment step before electroless deposition of Cu lines. The obtained pattern could be effectively controlled by adjusting the parameters including printing droplet spacing, operating voltages, substrate temperature, electroless plating time and temperature. Optical microscope observation showed that a continuous pattern was formed with a printing voltage of 37 V, space of drop was about 30 μm and the substrate temperature was 50 °C. When eletroless plating with plating solution at 60 °C and at pH of 12.5, the smallest metallic line formed in this study is about 40 μm.

When molding thin light guide plates, high injection speed and high molding pressure are required to fill the mold completely, but it is easy to have parts with defects like high residual stress and high warpage. Inkjet printing is a drop-on-demand (DOD) and direct writing process, there is no need to fabricate stampers for the DOD processes thus it saves lots of time on the development of light guide plates. With those benefits, back light unit suppliers around the world have envisioned the DOD process as a great potential for fabricating thin light guide plates. The aim of this study is to develop a complete light guide plate fabrication process using inkjet printing technology. That includes ink selection, substrate surface treatment, microlens array design, printing process parameters determination, and printing qualities investigation. A Dimatix DMP-2800 inkjet printing machine is used for printing the microlens and a polyacrylamide-based ink is selected. To make the PMMA substrate more hydrophobic, it is coated with a thin Teflon layer before the printing process. For this specific combination of machine, ink and substrate, when the distance between inkjet nozzle and substrate is 0.7 mm and the driving voltage is 12 V the printed microlens has the best quality. Referring to the microlens size of light guide plates made by industry, the microlens with 38 μm in diameter and 26 μm in height are selected for this study. A 3″ light guide plate, designed with TracePro software, is successfully fabricated using the proposed ink-jet printing scheme. The optical measurement result indicated that the light guide plate has an averaged luminance of 1012.58 nits and a luminance uniformity of 83.85%. Thus work demonstrates the feasibility and effectiveness of utilizing inkjet printing technique to prepare light guide plates with low cost.

In this study, a porous Ti-alloy based implant with an interconnected channel structure (MAO-CaP-BMP2) is fabricated using a method combining 3D printing, microarc oxidation (MAO) treatment, and co-precipitation of Ca,P layer with BMP-2 technique. The macroporous structure with pore size of 600 μm made by 3D printing not only enhances the ingrowth of cells but also allows the formation of blood vessels inside the implant. As a result, the new bond formation is promoted. In addition, the microporous dioxide layer formed on the implant surface by MAO provides the sites for co-precipitation of Ca,P layer with BMP-2. The microstructure allows the prolonged release of BMP-2. Our results show that a sustained release of BMP-2 over 35 days is achieved for MAO-CaP-BMP2 group longer than Ti without MAO modification group and without Ca,P electrochemical deposition group. The slow release of BMP-2 at the bone/implant interface for a long period of time leads to enhancement of the osseointegration between the implant and surrounding bones. This result indicates that MAO-CaP-BMP2 is a good candidate of growth factor carrier. Successful regeneration of bone requires the concomitant processes of osteogenesis and neovascularization. MAO-CaP-BMP2 modified Ti-alloy implant is both osteoinductive and osteoconductive which can create better osteogenesis and angiogenesis. As a result, it can enhance bone formation.

Nowadays, micro injection molding became one of the technologies for micro manufacture. It is widely used as a cost-effective replication method for mass production of plastic parts. However, one of the challenges for micro molding is the shrinkage which will deteriorate the quality of the micro parts molded. The way to control and minimize the shrinkage is by mean of optimizing the molding parameters. Optimizing process parameter problems are routinely performed in the manufacturing industry, particularly in setting the final optimal process parameters. Final optimal process parameter setting is recognized as one of the most important steps in injection molding for improving the quality of molded products. In this study, Taguchi method was implemented in finding the optimal micro injection molding condition for minimum shrinkage of a micro gear in micro molding experiment. Analysis of Variance (ANOVA) was carried out to determine the most influential factor that contributes towards the shrinkage quality of micro gear. The influential factors that affecting shrinkage are packing time with a contribution of 32.47% and injection speed with a contribution of 22.34%.

This study integrated neural network optimal optical design and Roll to Roll microfabrication in the development of a flexible light guide film for liquid crystal display application. To achieve high luminance uniformity requirement, a neural network optimal process together with optical analysis was implemented in this study. Back-propagation neural network and genetic algorithm were applied to establish a light guide film optical quality predictor and to find the optimal micro pattern design respectively. The micro pattern was successfully duplicated on a 188 μm PET substrate with UV resin through Roll to Roll fabrication process. The measurement results showed that the replication rate is around 98 % while the luminance uniformity of light guide film reaches 74.9 %.

In this work, a method to fabricate copper pattern on an indium-doped tin oxide (ITO) glass substrate is described. This method involves ink-jet printing of a pH-sensitive chitosan-g-polyvinyl acetate/Pd nanoparticle (CTS-g-PVAc-Pd) based ink on an untreated ITO plate to create the catalytic sites, onto which copper is subsequently deposited by an electroless plating method. To prepare the CTS-g-PVAc-Pd nanoparticles, a pH-sensitive chitosan-g-polyvinyl acetate (CTS-g-PVAc) copolymer is utilized to self-reduce Pd nanoparticles. The pH-sensitive CTS chains function as stabilizing agent for noble metal nanoparticles in acidic ink solution. On the other hand, CTS-g-PVAc copolymers convert to hydrophilic CTS-g-poly(vinyl alcohol) via alkali hydrolysis during the electroless copper plating. Therefore, the copper film with dramatically enhanced adhesion is formed on the surface of ITO glass without special pretreatment step before electroless deposition of copper film. Our results show that this process yields copper line with width down to 60 μm and ITO plated with the copper coating has good electrical conductivity, with an electrical resistivity of about 5.4 μΩ cm.

Microlens arrays are a vital part of today’s optical systems, and advances in fabrication technology have broadened microlens array applications. The roll-to-roll fabrication process has an advantage in its fast and mass replication of microstructures, and it is a good fit for fabricating devices based on flexible substrates. To investigate the roll-to-roll process in the making of microlens arrays of different radii in the same process, this study designs microlens arrays with radii ranging from 55 to 240 µm and with a height of 15 µm. The material for the lens is an ultraviolet curable resin with a refractive index of 1.5. The lens pattern is first transferred to an 80-µm-thick stainless steel sheet through an etching process. The patterned sheet is then wrapped around a stainless steel roller for roll-to-roll fabrication of the microlens array film. The substrate for the microlens array is a polyethylene terephthalate film 188 µm in thickness. When operating with a substrate forward speed of 0.251 m/min (1 r/min) and imprinting pressure of 0.6 MPa, the replication rates achieved for both the radius and the height of the microlens arrays are about 97%. Single-peak filling patterns are found with the small radii lenses, while dual-peak patterns are found in lenses with bigger radii. Overall, this study demonstrates the potential of roll-to-roll in three-dimensional pattern fabrications and its application in microlens array optical film fabrication.

This study proposes a two-stage system to optimize the etching process parameter for making a light guide plate (LGP) stamper. The multi-quality characteristics of the parameter settings include depth and uniformity of the microstructures formed in the LGP stamper. The control factors to conduct the process are etching temperature, specific gravity, spray pressure, transfer speed, and oscillating rate. The first stage is to conduct signal-to-noise (S/N) ratio optimization using Taguchi orthogonal array experiments. After conducting the etching process in microstructure, the experimental data can be translated and tested by back-propagation neural networks in order to create S/N ratio and the other quality characteristics predictors. In addition, the S/N ratio predictor and genetic algorithms are used together to obtain combinations of settings and to find the maximized process parameters on S/N ratios. As a result, the quality variance could be minimized. The second stage demonstrates quality characteristics optimization by pushing the process qualities to the targeted specifications. The analysis of variance (ANOVA) is employed to determine the significant control factors. Then, a statistical analysis using the aforementioned quality predictor, S/N ratios predictor, and particle swarm optimization is implemented to simulate the targeted specifications and then find a suitable specifications combination and the most stable and qualified process.

This study proposed a two-stage LED lens design optimization system, and used the viewing angle and the luminance uniformity as the optical quality objective. Optical design software (TracePro) and the orthogonal table of Taguchi method were used for simulation experiment. In the first stage, the viewing angle was used as the optical quality objective to find out the preliminary optimization of lens shape. The optimal LED lens size parameter combination of the first stage was used in the second stage to create L25(56) orthogonal table, and then the Back-Propagation Neural Network (BPNN) was used to establish the LED lens quality predictor to predict the FWHM angle and luminance uniformity in different overall sizes. The Genetic Algorithm (GA) with the quality predictor was used to find out the optimum design parameter combination of overall size according to the required quality objective. A LED with wide viewing angle and high luminance uniformity was taken as an example in this study to design a LED optical lens with 135^o FWHM angle and 93.35% uniformity.

Microceramic injection molding (µCIM) has shown great potential in making small-scale intricate near-net-shape parts with the competitive price for mass production. In this study, multi-exposure multi-development UV-Lithographie, Galvanoformung, Abformung (LIGA), µCIM, variothermal temperature control, and Taguchi experimental method are integrated and applied to develop a multilayer micropart with zirconia (ZrO2) feedstock. With the variothermal temperature control, a 335 μm thickness multilayer micropart having 100 microholes of 21.6 μm in diameter has been successfully molded. Optimization of the molding parameters to achieve high microhole replication quality molding was carried out with Taguchi experimental method. Results from Taguchi experiments reveal that mold temperature (40.9%), back pressure (31.8%), and injection speed (26.8%) contribute most to the replication quality, while ejection temperature has little effect on it. After further sintering processing, the thickness of the part is 200 μm, the final microhole diameter is 17.3 μm and its depth is 35.3 μm while the width of the channel is 38.5 μm and its height is 35.3 μm, and the accumulated aspect ratio of the dual layer structure is 2.95.

A micro lancet needle of 623 µm in length, 203 µm in width, and 106 µm in thickness was analyzed and fabricated with ANSYSY software and LIGA-like process. Biodegradable polylactic acid (PLA) was used as molding material. Taguchi method was utilized in the experiment to study the effects of molding parameters on the stiffness of the microneedle. Results showed that melt temperature has the most significant effects on the strength of the PLA microneedles. This study also demonstrates LIGA-like and micromolding techniques can be applied for mass replication of microneedles.

This paper presents an integrated microtechnology for the fabrication of a 3-D structure nozzle plate for a 1200-dots-per-inch (dpi) inkjet printhead. The 3-D structure nozzle plate contains a fluidic channel, nozzle chamber, and 432 conical nozzles whose taper angle is about 9deg-11deg to vertical. When the integrated 3-D structure nozzle plate is packaged onto the printhead, there is no need for alignment between the nozzle and the ink chamber, as there is when conventional production methods are employed. Therefore, misalignment of the nozzle and ink chamber is avoided, thereby reducing the cost by up to 50%, as well as greatly improving the print quality. This paper demonstrated the integration of excimer laser technology and microinjection molding to fabricate a 3-D structure nozzle plate. Excimer laser technology was used to create the high aspect ratio pattern with a tapered angle structure, and then, high-hardness Ni-Co alloy microelectroforming technology was used to achieve micromold insertion of the nozzle plate. In the microinjection molding, a variotherm control system was utilized for rapid heating to the mold temperature, which must be close to the glass temperature to ensure a good replication of the nozzle plate. The experiment resulted in the fabrication of a 3-D structure nozzle plate 2.7 mm in width and 10.8 mm in length. The total thickness was not more than 80 plusmn2 mum (ink channels, nozzle chamber, and nozzle plate), and the diameter and pitch of the nozzle holes were 25 plusmn2 mum for the outlet, 43 plusmn2 mum for the inlet, 84 plusmn2 mum in pitch, and 30 plusmn2 mum for the ink channel. Using this 3-D structure nozzle plate improved the competitiveness of the inkjet printhead. We have demonstrated the manufacture of the main parts of the 3-D structure nozzle plate for a 1200-dpi printhead; the aforementioned fabrication process yields satisfactory results and can be applied to commercial production.

This paper presents the development of a parameter optimization system that integrates mold flow analysis, the Taguchi method, analysis of variance (ANOVA), back-propagation neural networks (BPNNs), genetic algorithms (GAs), and the Davidon–Fletcher–Powell (DFP) method to generate optimal process parameter settings for multiple-input single-output plastic injection molding. In the computer-aided engineering simulations, Moldex3D software was employed to determine the preliminary process parameter settings. For process parameter optimization, an L25 orthogonal array experiment was conducted to arrange the number of experimental runs. The injection time, velocity pressure switch position, packing pressure, and injection velocity were employed as process control parameters, with product weight as the target quality. The significant process parameters influencing the product weight and the signal to noise (S/N) ratio were determined using experimental data based on the ANOVA method. Experimental data from the Taguchi method were used to train and test the BPNNs. Then, the BPNN was combined with the DFP method and the GAs to determine the final optimal parameter settings. Three confirmation experiments were performed to verify the effectiveness of the proposed system. Experimental results show that the proposed system not only avoids shortcomings inherent in the commonly used Taguchi method but also produced significant quality and cost advantages.

This paper presents a novel LIGA-like process to fabricate the nozzle plate for matching the requirements of the 600 dpi inkjet printhead. This novel fabrication technique reduces the production cost from 100% current process to 50%. This mass production technique comprises two main technologies: Ni-Co electroforming and plastic injection molding. The nozzle plate consists ink channels, ink cavities, and nozzles for enhancing the integrity and excusing the assembly process. The dimensions of nozzle plate are 4.16mm in width and 7.3mm in length, respectively. Total thickness of micro-nozzle plates are thickness≦100um(ink channels and ink cavities), and the diameter and pitch of the nozzle holes are 40±3um and 168±3 um, respectively. Straightly speaking, for being the main compositions of the 600 dpi inkjet printhead design, the above fabrication process is qualified enough and capable of yielding satisfactory results.

To reduce the photoresist usage and understand the film spreading process, this study performs flow visualization experiments and numerical simulations. This paper is the first work to show that in the early stage of the spin coating process, the spreading of photoresist is mainly governed by the photoresist injection. Then, instability fingers are formed due to the centrifugal forece. Accompanied by the growing of fingers in length, the Coriolis force broadens the width of the fingers. The numerical results agree with the measured liquid front history at very short times. The difference between the numerical results and experiment data gradually arises due to the formation of instability fingers. The critical injection rate for fully coating a wafer increases with decreasing injection volume. Under a fixed wafer rotating speed, increasing the injection rate can significantly reduce the photoresist usage. To assist in the design and operation of the spin coating process, a regime map for injection rate and injection volume is provided.

Concepts of spatially-variable fertilizer and pesticide application are discussed. Commercial applicators are described which use Global Positioning Systems (GPS) or other location technologies to apply fertilizer and pesticide according to predetermined stepoint maps. The dynamics of the applicator are shown to have important performance effects. Command feedforward control can significantly improve the performance. Further research is needed on understanding the effects of the various error sources.

In this study, we developed a knowledge-based engineering (KBE) system to assist engineers in promptly predicting a near-optimal assembly sequence. A three-stage assembly optimization approach with some heuristic working rules was employed to establish the proposed system. In the first stage, Above Graph and a transforming rule were used to create a correct explosion graph of the assembly models. In the second stage, a three-level relational model graph, with geometric constraints and assembly precedence diagrams, was generated to create a completely relational model graph, an incidence matrix, and a feasible assembly sequence. In the third stage, a robust back-propagation neural network engine was developed and embedded in the Siemens NX system. System users can easily access the volume, weight, and feature number through the Siemens NX system interface, input the related parameters such as contact relationship number and total penalty value, and predict a feasible assembly sequence via a robust engine. Three real-world examples were used to evaluate the feasibility of the KBE system. The results show that the proposed system can facilitate feasible assembly sequences and allow designers to recognize contact relationships, assembly difficulties, and assembly constraints of three-dimensional components in a virtual environment type.

The role of a backlight module's light guide plate (LGP) is to guide the light source to reach both high luminance and high luminance uniformity purposes. Most of the previous studies focused on analyzing a single light source LGP; however, there are many LGPs with more than one light source in the market. In this study, an L-type light source 7" LGP with 91.25% luminance uniformity was designed and analyzed using commercial optical analysis software. LIGA-like technology has been applied to fabricate the molding stamper and molding of the LGP in this study. A LGP molded with a 350 ton injection molding machine has a luminance uniformity of 85.26% which is higher than the current industry specification.

A prism-based brightness enhancement film (BEF), has been investigated through computer-aided optical analysis and experiments in this study. The prism film was fabricated on a 100 microm thick PET film substrate using roll-to-roll (R2R) process with UV curable resins of different refractive indices. The results from both optical analysis and experiments showed that resins with higher refractive indices have better on-axis luminous gain. The prism structures fabricated on the substrate achieved a replication rate of 97.54% in this study. Compared with the 3M BEF, the prism films developed in this study are improved in on-axis luminous gains when the refractive index of the resin is higher than 1.53.

Microneedles can be used for biomedical applications such as skin prick, blood collection, and drug delivery, etc. Many of the microneedles were fabricated by traditional machining. In this study, a micro lancet needle for blood test application was fabricated using micro injection molding technique, biodegradable polylactic acid (PLA) was used as molding material. The dimension of the microneedle is 623 mum in length, 203 mum in width, and 106 mum in thickness. The mold insert for molding this microneedle was fabricated using LIGA-like techniques. ANSYS CAE software was employed to determine the microneedle's dimensions, and the strength of microneedle was designed to withstand a pressure higher than 3.5 MPa which is necessary for breaking through human skin. Micromolding of the design microneedle was carried out using battenfeld microsystem 50 microinjection molding machine. In order to achieve optimal microneedle quality, Taguchi method was utilized in the experiment. The injection molding parameters including melt temperature, mold temperature, injection speed, and holding speed have been selected as control parameters in the experiment. Experimental results showed that melt temperature and mold temperature have the most significant effects on the strength of the PLA microneedles, and this study also demonstrates that LIGA-like and micromolding techniques can been applied for mass replication of microneedles.

This research integrates Taguchipsilas parameter design method, back-propagation neural networks (BPNN), and Davidon-Fletcher-Powell (DFP) method to optimize the process parameter settings of plastic injection molding. Taguchipsilas parameter design method is used to arrange an orthogonal array experiment and to reduce the number of set-test cycles. Injection time, velocity pressure switch position, packing pressure, and injection velocity are selected as process control parameters and product weight is selected as the single product quality. The experimental data of Taguchipsilas parameter design method are used for effectively training and testing BPNN. Then, BPNN is combined with DFP to search out the final optimal process parameter settings. Finally, a confirmation experiment is performed to confirm the effectiveness of the final optimal process parameter settings. The experimental results show that the proposed effective process parameter optimization approach can avoid shortcomings inherent in the application of trial-and-error processes or the conventional Taguchi parameter design method. Furthermore, the proposed approach can effectively assist engineers in determining optimal initial process parameter settings and achieving competitive advantages on product quality and costs.