scholarly journals The FEM Simulation of Ultra-precision Grinding of Optical Glass with Micro-structured Coarse-Grained Diamond Wheels

2017 ◽  
Author(s):  
Bing Guo ◽  
Mingtao Wu ◽  
Qingliang Zhao
Keyword(s):  
Optical Glass ◽  
Fem Simulation ◽  
Coarse Grained ◽  
Precision Grinding ◽  
Ultra Precision

scholarly journals Influence of servo characteristics on crack generation in ultra-precision grinding of optical glass lenses

Procedia CIRP ◽  
2018 ◽  
Vol 77 ◽  
pp. 130-133
Author(s):  
Takumi Suetomi ◽  
Yasuhiro Kakinuma ◽  
Masahiko Fukuta ◽  
Katsutoshi Tanaka
Keyword(s):  
Optical Glass ◽  
Precision Grinding ◽  
Crack Generation ◽  
Ultra Precision ◽  
Glass Lenses

New Tool Concepts for Ultra-Precision Grinding

2012 ◽  
Vol 516 ◽  
pp. 287-292 ◽  
Author(s):  
Ekkard Brinksmeier ◽  
Yildirim Mutlugünes ◽  
Grigory Antsupov ◽  
Kai Rickens
Keyword(s):  
Surface Roughness ◽  
Wear Resistance ◽  
Surface Finish ◽  
Cvd Diamond ◽  
Coarse Grained ◽  
Grinding Wheels ◽  
Precision Grinding ◽  
Diamond Grinding ◽  
Ultra Precision ◽  
Sharp Edges

This paper presents advanced tools for ultra precision grinding which offer a high wear resistance and can be used to generate high-quality parts with an ultraprecise surface finish. The first approach features defined dressed, coarse-grained, single layered, metal bonded diamond grinding wheels. These grinding wheels are called Engineered Grinding Wheels and have been dressed by an adapted conditioning process which leads to uniform abrasive grain protrusion heights and flattened grains. This paper shows the results from grinding optical glasses with such Engineered Grinding Wheels regarding the specific forces and the surface roughness. The results show that the cutting mechanism turns into ductile removal and optical surfaces are achievable. On the other hand, the specific normal force F´n increases due to increased contact area of the flattened diamond grains. It is shown that the topography of the Engineered Grinding Wheels has a strong beneficial influence on surface roughness. The second new tool for ultra precision grinding is made of a CVD (Chemical Vapour Deposition) poly-crystalline diamond layer with sharp edges of micrometre-sized diamond crystallites as a special type of abrasive. The sharp edges of the crystallites act as cutting edges which can be used for grinding. It is shown that by using CVD-diamond-coated grinding wheels a high material removal rate and a high surface finish with surface roughness in the nanometre range can be achieved. The CVD-diamond layers exhibit higher wear resistance compared to conventional metal and resin bonded diamond wheels. In conclusion, this paper shows that not only conventional fine grained, multi-layered resinoid diamond grinding wheels but also coarse-grained and binderless CVD-coated diamond grinding wheels can be applied to machine brittle and hard materials by ultra precision grinding.

Ultra-precision grinding of optical glass lenses with La-doped CeO2 slurry

CIRP Annals ◽  
2019 ◽  
Vol 68 (1) ◽  
pp. 345-348 ◽  
Author(s):  
Yasuhiro Kakinuma ◽  
Yoshiki Konuma ◽  
Masahiko Fukuta ◽  
Katsutoshi Tanaka
Keyword(s):  
Optical Glass ◽  
Precision Grinding ◽  
Ultra Precision ◽  
Doped Ceo2 ◽  
Glass Lenses ◽  
La Doped

Basic Study on High Efficiency Ultra-Precision Grinding of the Optical Glass Lens

2014 ◽  
Vol 1017 ◽  
pp. 21-26 ◽  
Author(s):  
Rei Sekiguchi ◽  
Shun Yoshikawa ◽  
Yasuhiro Kakinuma ◽  
Katsutoshi Tanaka ◽  
Masahiko Fukuta
Keyword(s):  
Surface Quality ◽  
High Efficiency ◽  
Optical Glass ◽  
High Surface ◽  
Precision Grinding ◽  
Form Accuracy ◽  
Large Aperture ◽  
Highly Efficient ◽  
Ultra Precision ◽  
Glass Lenses

The demand for large aperture lenses with high surface quality and form accuracy used for single-lens reflex cameras has been increasing. Generally, large aperture glass lenses are produced by ultra-precision grinding. Considering the increasing global competition, the grinding process has to be improved. However, highly efficient grinding causes worse surface quality, which leads to much polishing and ultimately results in lower form accuracy. Thus in this study, aiming at the realization of highly efficient and precise grinding of glass lenses, cross grinding of optical glass BK7 is carried out. As a first step of the study, the influence of grinding conditions on the surface quality is investigated experimentally.

Basic Study on Ductile-Mode Grinding of Optical Glass Lenses with Rubber Bonded Diamond Wheels

2016 ◽  
Vol 874 ◽  
pp. 241-246
Author(s):  
Yuya Kawana ◽  
Rei Sekiguchi ◽  
Yuta Mizumoto ◽  
Yasuhiro Kakinuma ◽  
Katsutoshi Tanaka ◽  
...  
Keyword(s):  
Optical Glass ◽  
High Surface ◽  
Chip Thickness ◽  
Precision Grinding ◽  
Basic Study ◽  
High Surface Quality ◽  
Large Aperture ◽  
Single Lens ◽  
Ductile Mode ◽  
Ultra Precision

Large aperture lenses with high surface quality are demanded for professional imaging products such as single-lens reflex cameras and astronomical telescopes. Large aperture optical lenses are shaped by ultra-precision grinding and finished by prolonged polishing. However, the prolonged polishing process leads to deterioration of the form accuracy. In order to reduce the amount of polishing, ductile-mode ultra-precision grinding is demanded. In this study, a rubber bonded wheel, which has a low elastic modulus, is used for grinding of spherical glass BK7, and influence of the hardness of the rubber bonded wheel and abrasive chip thickness on brittle fracture and surface roughness are experimentally investigated.

Sign in / Sign up

Export Citation Format

Share Document