A Study of Two-Stage Micro Injection Compression Molding Process for Diffractive Optical Lens

2007 ◽  
Vol 364-366 ◽  
pp. 1211-1214 ◽  
Author(s):  
Chao Chang Arthur Chen ◽  
Shi Chi Kao
Keyword(s):  
Mold Insert ◽  
Fresnel Lens ◽  
Compression Molding ◽  
Piezo Actuator ◽  
Molding Process ◽  
Spherical Lens ◽  
Two Stage ◽  
Optical Elements ◽  
Micro Features ◽  
Injection Compression Molding

This research aimed to develop a novel two-stage micro injection compression molding (μ-ICM) process for fabrication of plastic diffractive optic elements (DOE). The DOE was designed with the spherical coefficients and the Fresnel lens. A piezo actuator was installed inside the mold plate for activating the mold insert for the second compression motion for micro ICM of the DOE lens. The first experiment proceeded to find the operation window of Fresnel lens and then compare the product weight of flat spherical lens by injection molding (IM), injection compression molding (ICM) and μ-ICM. The second experiment was to investigate the effectiveness of micro compression activated by the piezo actuator by the transfer ratio of grooves (TRG) of the DOE lens with spherical lens and Fresnel lens. Results showed that the μ-ICM of the DOE can obtain the highest TRG than that of IM and conventional ICM processes. Therefore, results of this research can be explored to related aspheric optical elements with micro features, such as fine lens used in the zoom lens of camera.

scholarly journals Manufacturing Signatures of Injection Molding and Injection Compression Molding for Micro-Structured Polymer Fresnel Lens Production

Micromachines ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 653 ◽  
Author(s):  
Dario Loaldi ◽  
Danilo Quagliotti ◽  
Matteo Calaon ◽  
Paolo Parenti ◽  
Massimiliano Annoni ◽  
...  
Keyword(s):  
Injection Molding ◽  
Laser Scanning ◽  
Injection Pressure ◽  
Fresnel Lens ◽  
Uncertainty Budget ◽  
Compression Molding ◽  
Process Conditions ◽  
Dimensional Measurements ◽  
Micro Features ◽  
Injection Compression Molding

Injection compression molding (ICM) provides enhanced optical performances of molded polymer optics in terms of birefringence and transmission of light compared to Injection molding (IM). Nevertheless, ICM requires case-dedicated process optimization to ensure that the required high accuracy geometrical replication is achieved, particularly especially in the case of surface micro-features. In this study, two factorial designs of experiments (DOE) were carried out to investigate the replication capability of IM and ICM on a micro structured Fresnel lens. A laser scanning confocal microscope was employed for the quality control of the optical components. Thus, a detailed uncertainty budget was established for the dimensional measurements of the replicated Fresnel lenses, considering specifically peak-to-valley (PV) step height and the pitch of the grooves. Additional monitoring of injection pressure allowed for the definition of a manufacturing signature, namely, the process fingerprint for the evaluation of the replication fidelity under different process conditions. Moreover, considerations on the warpage of parts were related to a manufacturing signature of the molding processes. At last, the global part mass average and standard deviation were measured to correlate local geometrical replication performances with global part quality trends.

Challenges in the Fabrication of Microstructured Polymer Optics

2019 ◽  
Vol 7 (2) ◽  
Author(s):  
M. Roeder ◽  
P. Schilling ◽  
K.-P. Fritz ◽  
T. Guenther ◽  
A. Zimmermann
Keyword(s):  
Mold Insert ◽  
Compression Molding ◽  
Direct Writing ◽  
Laser Direct Writing ◽  
Optical Elements ◽  
Polymer Optics ◽  
Process Chains ◽  
Ultra Precision ◽  
Injection Compression Molding ◽  
Complete Process

The fabrication of microstructured polymer optics enables a multitude of new options in the design of technical optics. However, challenges arise along the varying process chains of mold insert fabrication, integration into molding tools, replication by means of injection compression molding and metrology. In order to study the effects, diffractive optical elements (DOE) and microlens arrays (MLA) are fabricated using two different process chains. DOEs are fabricated using a laser direct writing (LDW) based mold insert fabrication. The MLA mold insert is produced using ultra-precision milling (UP-milling). Both optical parts are replicated using injection compression molding. The occurring effects are discussed and the results show, that with complete process control high quality microstructured polymer optical parts can be produced and characterized.

Injection Compression Molding Process and Mould Design of Plastic Optical Lens

2012 ◽  
Vol 501 ◽  
pp. 321-324 ◽  
Author(s):  
Qiu Xiang Bu ◽  
Jian Yi Zhu ◽  
Qing Zhen Yin
Keyword(s):  
Dimensional Accuracy ◽  
Compression Molding ◽  
Molding Process ◽  
Optical Lens ◽  
Stress Problem ◽  
Injection Process ◽  
Deformation Problem ◽  
Mould Design ◽  
Injection Compression Molding

The characteristic of injection compression molding technology and the application of the technology in mould for the plastic optical lens were introduced. The structure and the work principle of the mould for optical lens were designed and described, The stress problem in the injection process was resolved, the deformation problem and dimensional accuracy of product were improved.

Three-dimensional numerical analysis of injection-compression molding process

2011 ◽  
Vol 52 (4) ◽  
pp. 901-911 ◽  
Author(s):  
Jae-Yun Ho ◽  
Jang Min Park ◽  
Tae Gon Kang ◽  
Seong Jin Park
Keyword(s):  
Numerical Analysis ◽  
Three Dimensional ◽  
Compression Molding ◽  
Molding Process ◽  
Injection Compression Molding

Micro-injection Molded Polymeric Surfaces for the Maintenance of Human Mesenchymal Stem Cells (hMSCs)

2013 ◽  
Vol 1499 ◽  
Author(s):  
Meghan E. Casey ◽  
John W. Rodgers ◽  
Courtney E. LeBlon ◽  
John P. Coulter ◽  
Sabrina S. Jedlicka
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Injection Molding ◽  
Silicon Wafer ◽  
Human Mesenchymal Stem Cells ◽  
Mold Insert ◽  
High Volume ◽  
Injection Molding Process ◽  
Molding Process ◽  
Micro Features

ABSTRACTIn this work, we take advantage of injection molding as a high volume and repeatable method to create surface areas for the growth of human mesenchymal stem cells (hMSCs). Ultraviolet lithography, combined with deep reactive ion etching, was used to generate micro-features over a relatively large surface area of a silicon wafer. The micro-featured silicon wafer was used as a mold insert for the micro-injection molding process to create polystyrene and low density polyethylene surfaces. Micro-geometry was used to alter the effective surface stiffness of the polymer substrate. Created samples were characterized via scanning electron microscopy and tensile testing. hMSCs were seeded onto samples for initial studies. Actin and vinculin were visualized through ICC to compare cytoskeletal elements. Changes in cell morphology were examined using ICC. Results indicate that injection molding of microfeatured substrates is a viable technique to produce surfaces amenable to stem cell growth.

A Numerical Study of an Injection-Compression Molding Process by Using a Moving Grid

2012 ◽  
Vol 249-250 ◽  
pp. 472-476 ◽  
Author(s):  
Bambang Arip Dwiyantoro
Keyword(s):  
Stokes Equations ◽  
Numerical Study ◽  
Three Dimensional ◽  
Compression Molding ◽  
Navier Stokes ◽  
Molding Pressure ◽  
Moving Grid ◽  
Molding Process ◽  
Melt Temperature ◽  
Injection Compression Molding

A numerical study for the simulation of melt in an injection-compression molding process by using moving grid is proposed in this paper. The fully three-dimensional Navier-Stokes equations are solved together with the front transport equation using a front capturing approach. Different from previous studies, the proposed model can take the movement of cavity through a moving grid approach. The melt filling of a disk is conducted to illustrate the applications of the proposed numerical model with several computations under different processing conditions. The numerically predicted results show the influence of compression time or compression speed in determining the molding pressure and the melt temperature.

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