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Yang, Sun-Choel;Won, Jong-Ho
- Journal of the Korean Society for Precision Engineering
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- v.27 no.12
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- pp.9-14
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- 2010
Using an IR (infrared) optical system of observation and research were performed long before. Nowadays satellites equipped with IR optical system observe the earth and universe. In this paper, we developed the IR optical system for main payload of the STSAT-3 (Science and Technology Satellite -3). We studied the ultra precision machining technique to fabricate FPL-53 lenses which is the IR optical material for space observation camera of the STSAT-3. DOE (Design of Experiment) was used to find best machining characteristic for FPL-53. Finally we fabricated FPL-53 aspheric lens with the form accuracy of P-V $0.36\;{\mu}m$.
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권우순;김동현;난바의치
- Proceedings of the Korean Society of Precision Engineering Conference
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- 2003.06a
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- pp.538-541
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- 2003
Ultra-precision machining was carried out on a electroless nickel materials using single crystal diamond tools. The effects of the cutting velocity, the tool length, the tool nose radius, the feed rate and depth of cut on the surface roughness were studied. In this paper, the cutting condition for getting nano order smooth surface of electroless nickel have been examined experimentally by the ultra-precision machine and single crystal diamond tools. And also. the surface roughness was measured by the three dimension
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Hwang, Yeon;Cha, Du-Hwan;Kim, Jeong-Ho;Kim, Hye-Jeong
- Journal of the Korean Society for Precision Engineering
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- v.29 no.3
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- pp.261-265
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- 2012
In this study, glassy carbon was ground for lens core of glass mold press. Ultraprecision grinding process was applied for machining of core surfaces. During the process, brittle crack occurred because of hard-brittleness of glassy carbon. Author investigated optimized grinding conditions from the viewpoint of ductile mode grinding. Geometrical undeformed chip thickness was adopted for critical chip thickness that enables crack free surface. Machined cores are utilized for biaspheric glass lens fabrication and surfaces of lens were compared for verification of ground surface.
https://doi.org/10.7736/KSPE.2012.29.3.261 인용 PDF KSCI

이대희;이종호;김호상;민흥기;김민기;김태형
- Proceedings of the Korean Society of Precision Engineering Conference
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- 2002.10a
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- pp.283-286
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- 2002
This paper presents the straightness compensation system which is a device for improving the machining accuracy of ultra-precision machines by synchronizing the position of diamond tool tip with machine error motion. Sine it is actuated by piezoelectric actuator with highly nonlinear hysteresis characteristics, the feedback control schemes such as Proportional Integral(PI), are required and realized by measuring the displacements of diamond tool tip. for the better tracking performance, the controller was implemented using TMS320C32 32bit floating-point DSP which is fast so that the real-time control is possible. In addition, stand alone type DSP board was chosen fur the easy assembly into the ultra-precision machines. The experimental results show good command tracking performance and the motion error of the machine is satisfactorily compensated during the machining process.
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Jeong S.H.;Kim H.U.;Choi S.B.;Kim G.H.;Park J.H.
- Proceedings of the Korean Society of Precision Engineering Conference
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- 2005.10a
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- pp.314-317
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- 2005
As demands of VBNS and VDSL increase, the development of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, and WDM elements increases. The alignment and the attachment technology are very important in the fabrication of optical elements. The ultra precision stage wasn't yet applied in the optical alignment and the optical element alignment was taken too many times. In this paper, the optical element alignment of ultra precision positioning stage was studied. The alignment algorithm is comprised of field search and peak search algorithms. The procedure of the alignment algorithms applied to the ultra precision positioning stage are developed by LabView programming.
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