Additive manufacturing: a new approach to realize complex and unconventional optical components

Author(s):  
Andreas Heinrich ◽  
Manuel Rank ◽  
Sangeetha Suresh Nair ◽  
Y. Bauckhage ◽  
Phillipe Maillard
2010 ◽  
Vol 438 ◽  
pp. 65-72 ◽  
Author(s):  
Andreas Mehner ◽  
Ju An Dong ◽  
Timo Hoja ◽  
Torsten Prenzel ◽  
Yildirim Mutlugünes ◽  
...  

The demand for high precision optical elements as micro lens arrays for displays increases continually. Economic mass production of such optical elements is done by replication with high precision optical molds. A new approach for manufacturing such molds was realized by diamond machinable and wear resistant sol-gel coatings. Crack free silica based hybrid coatings from base catalyzed sols from tetraethylorthosilicate (TEOS: Si(OC2H5)4) and methyltriethoxysilane (MTES: Si(CH3)(OC2H5)3) precursors were deposited onto pre-machined steel molds by spin coating process followed by a heat treatment at temperatures up to 800°C. Crack-free multilayer coatings with a total thickness of up to 18 µm were achieved. Micro-machining of these coatings was accomplished by high precision fly cutting with diamond tools. Molds with micro-structured coatings were successfully tested for injection molding of PMMA optical components. The wear resistance of the coatings was successfully tested by injection molding of 1000 PMMA lenses. Hardness and elastic modulus of the coatings were measured by nano indentation. The chemical composition was measured by X-ray photo electron spectroscopy (XPS) as a function of the sol-gel processing parameters.


2012 ◽  
Vol 523-524 ◽  
pp. 1001-1005 ◽  
Author(s):  
Martin Hünten ◽  
Daniel Hollstegge ◽  
Fritz Klocke

Manufacturing of micro optical components is approached with many different technologies. In this paper it is presented how the precision glass molding process is enabled to manufacture micro optical components made out of glass. In comparison to the existing glass molding technology the new approach aims for molding entire glass wafers including multiple micro optical components. It is explained which developments in the filed of simulation, mold manufacturing and molding were accomplished in order to enable the precision glass molding on wafer scale.


2018 ◽  
Vol 5 (5) ◽  
pp. 939-945 ◽  
Author(s):  
Grace X. Gu ◽  
Chun-Teh Chen ◽  
Deon J. Richmond ◽  
Markus J. Buehler

A new approach to design hierarchical materials using convolutional neural networks is proposed and validated through additive manufacturing and testing.


2017 ◽  
Vol 23 (2) ◽  
pp. 434-447 ◽  
Author(s):  
Yuanbin Wang ◽  
Robert Blache ◽  
Xun Xu

Purpose This study aims to review the existing methods for additive manufacturing (AM) process selection and evaluate their suitability for design for additive manufacturing (DfAM). AM has experienced a rapid development in recent years. New technologies, machines and service bureaus are being brought into the market at an exciting rate. While user’s choices are in abundance, finding the right choice can be a non-trivial task. Design/methodology/approach AM process selection methods are reviewed based on decision theory. The authors also examine how the user’s preferences and AM process performances are considered and approximated into mathematical models. The pros and cons and the limitations of these methods are discussed, and a new approach has been proposed to support the iterating process of DfAM. Findings All current studies follow a sequential decision process and focus on an “a priori” articulation of preferences approach. This kind of method has limitations for the user in the early design stage to implement the DfAM process. An “a posteriori” articulation of preferences approach is proposed to support DfAM and an iterative design process. Originality/value This paper reviews AM process selection methods in a new perspective. The users need to be aware of the underlying assumptions in these methods. The limitations of these methods for DfAM are discussed, and a new approach for AM process selection is proposed.


Author(s):  
Nathan Decker ◽  
Qiang Huang

Abstract While additive manufacturing has seen tremendous growth in recent years, a number of challenges remain, including the presence of substantial geometric differences between a three dimensional (3D) printed part, and the shape that was intended. There are a number of approaches for addressing this issue, including statistical models that seek to account for errors caused by the geometry of the object being printed. Currently, these models are largely unable to account for errors generated in freeform 3D shapes. This paper proposes a new approach using machine learning with a set of predictors based on the geometric properties of the triangular mesh file used for printing. A direct advantage of this method is the simplicity with which it can describe important properties of a 3D shape and allow for predictive modeling of dimensional inaccuracies for complex parts. To evaluate the efficacy of this approach, a sample dataset of 3D printed objects and their corresponding deviations was generated. This dataset was used to train a random forest machine learning model and generate predictions of deviation for a new object. These predicted deviations were found to compare favorably to the actual deviations, demonstrating the potential of this approach for applications in error prediction and compensation.


2020 ◽  
Vol 32 ◽  
pp. 101006 ◽  
Author(s):  
Yulin Xiong ◽  
Song Yao ◽  
Zi-Long Zhao ◽  
Yi Min Xie

2015 ◽  
Vol 76 (7) ◽  
Author(s):  
Nor Azura Mohamed ◽  
Zainul Ahmad Rajion

The treatment of auricle defect can be by surgical or prosthetic ear rehabilitation depending on the condition.  Current practice by surgeon for prosthetic ear rehabilitation require patient to go for osseointegrated craniofacial implant surgery for retention of the prosthetic ear.  Impression technique play a vital role in accurate reproduction of affected and unaffected ears, orientation of the ear during wax try in and fabrication of ear prostheses. Traditionally, the wax pattern was created from the impression taken from patient and the final prosthesis is processed with silicone material.  This conventional method has always been time consuming, massive work and caused discomfort to patient.  Moreover the accuracy of the final prosthetic sometimes was not satisfied. Improvement in medical imaging technology whereby data from computerized tomography (CT) in 2D format can be converting to 3 dimensional images gave tremendous view for surgeon to visualize the result.  A new and impressive advance in the development of additive manufacturing technology is now being able to be applied in medical field.  The widespread use of computer-aided design (CAD) combine with computer aided manufacturing (CAM) produced the momentum and desire to translate the 3-D images into physical models. Studies and research have indicated the viability of using medical imaging technology, computer aided design (CAD) and additive manufacturing techniques in prosthetics.  This paper proposed a novel method of fabricating the prosthetic ear applying mirror image technique to reconstruct the missing ear, and then fabricate the 3D model of the prosthetic ear using Stereolitography (SLA) technology that will become the master mold to produce the final prosthetic ear.  This method eliminates the traditional wax pattern procedure. A clinical study is done onto a patient in HUSM and comparison is made between traditional method vs new approach using computer aided technology.  Result showed that there is significant different between traditional and new approach design.  The new method also shows time reduction during design and fabrication stage.  


Sign in / Sign up

Export Citation Format

Share Document