• Title/Summary/Keyword: precision of measurement

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비구면 렌즈의 형상 측정을 위한 접촉식 프로브 기술 개발 (Contact Probing Technique for Profile Measurement of Aspheric Lenses)

  • 유승봉;장인철;김승우
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2000년도 춘계학술대회 논문집
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    • pp.603-606
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    • 2000
  • This dissertation is concerned with ultra-precision profile measurement of aspheric surfaces using contact probing technique. A contact probe has been designed as a sensing device to obtain measuring resolutions in nanometer regime utilizing a leaf spring mechanism and a capacitive-type sensor. The contact probe is attached on the z-axis during measurement while aspheric objects are supported on an precision xy-stage whose lateral motions are monitored by a set of two orthogonal plane mirror type laser interferometers. Experimental results show that the contact probing technique developed in this investigation is capable of providing a repeatability of 50 nanometers with a $\pm$3$\sigma$ uncertainty of 300 nanometers. Thermal disturbance is found the most significant factor that should be precisely controlled for accurate measurement.

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He-Ne 레이저의 간섭을 이용한 고정밀 리니어 스케일의 제작에 관한 연구 (A Study on the Manufacturing of High Precision Linear Scale Using He-Ne Laser Interference)

  • 한응교;전병욱;이명호;박두원;노병옥
    • 한국정밀공학회지
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    • 제8권3호
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    • pp.82-92
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    • 1991
  • A study on the manufacturing of High Precision Linear Scalr using He-Ne Laser interference Of late, along with the advancement of precision machining technology, the requirement of super precision measurement increases as time goes on, and the accuracy of standard scale which is a basis of precision measurement has been cognized as a criterion of industrial development in a nationl. In this paper, we described on technology by which we could carve scale lines thru optical method under the condition of laboratory by using the coherence of He-Ne two-mode stabilized laser and in turn, put it to practical use as linear scale for the measurement of length. Hence in this research in the case of setting scale interval to 20 ${\mu}m$, we employed super precision scale-carving device associated with Ar laser and acousto optic modulator in lieu of flashing lamp scale-carving device, and we obtained as experimental result superior linear scales carved within the accuracy of ${\pm}$0.3${\mu}m$.

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측정 ANOVA의 분산성분에 의한 게이지 R&R 추정 (Estimation of Gauge R&R by Variance Components of Measurement ANOVA)

  • 최성운
    • 대한안전경영과학회지
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    • 제12권1호
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    • pp.199-205
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    • 2010
  • The research proposes the three-factor random measurement models for estimating the precision about operator, part, tool, and various measurement environments. The combined model with crossed and nested factors is developed to analyze the approximate F test by degrees of freedom given by Satterthwaite and point estimation of precisions from expected mean square. The model developed in this paper can be extended to the three useful models according to the type of nested designs. The study also provides the three-step procedures to evaluate the measurement precisions using three indexes such as SNR(Signal-To-Noise Ratio), R&R TR(Reproducibility&Repeatability-To-Total Precision Ratio), and PTR(Precision-To-Tolerance Ratio), The procedures include the identification of resolution, the improvement of R&R reduction, and the evaluation of precision effect.

고정밀 이송기구의 위치결정정밀도에 대한 측정불확도 요소 분석 (Measurement Uncertainty Analysis of Positioning Accuracy for High Precision Feed Mechanism)

  • 이정훈;윤상환;박민원
    • 한국정밀공학회지
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    • 제29권5호
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    • pp.494-499
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    • 2012
  • Reliable results can't be derived without the notion of measurement uncertainty. The reason is that the measured value includes a lot of uncertain factors. Finding the factor that affect the measurement of parameter is important for estimation of measurement uncertainty. In this paper, the evaluation of uncertainty analysis about positioning accuracy measurements of high precision feed mechanism is presented to evaluate the important factors of uncertainty.

AFM 측정법에 의한 알루미늄 합금의 초정밀 가공면 평가 연구 (A Study on Machined Surfaces Characteristics of Aluminum Alloy by AFM Measurement)

  • 이갑조;김종관
    • 한국공작기계학회논문집
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    • 제15권2호
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    • pp.81-86
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    • 2006
  • The machining parts must be produced within the specification of drawing and those will be able to meet function and efficiency. At that time, it is very important not only precision machine and machining technique but also the measurement technique. So, the improvement of measurement technique is to be joined together at once with improvement of machining technique. Finally, the quality and value of the parts are decided by precision measurement. This paper aims to study on the machined surfaces characteristics of aluminum alloy by AFM(Atomic force microscope) measurement. The objective is contribution to ultra-precision machining by exhibit foundation data of surface roughness and tool wear when parts are cutting with diamond tool at the factory.

Single-configuration FPP method에 의한 실리콘 웨이퍼의 비저항 정밀측정 (Precision Measurement of Silicon Wafer Resistivity Using Single-Configuration Four-Point Probe Method)

  • 강전홍;유광민;구경완;한상옥
    • 전기학회논문지
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    • 제60권7호
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    • pp.1434-1437
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    • 2011
  • Precision measurement of silicon wafer resistivity has been using single-configuration Four-Point Probe(FPP) method. This FPP method have to applying sample size, shape and thickness correction factor for a probe pin spacing to precision measurement of silicon wafer. The deference for resistivity measurement values applied correction factor and not applied correction factor was about 1.0 % deviation. The sample size, shape and thickness correction factor for a probe pin spacing have an effects on precision measurement for resistivity of silicon wafer.

미소 힘 측정을 위한 이중 전자기힘 보상방법 (Double Electro-Magnetic Force Compensation Method for the Micro Force Measurement)

  • 최임묵;우삼용;김부식;김수현
    • 한국정밀공학회지
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    • 제20권2호
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    • pp.104-111
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    • 2003
  • Micro force measurement is required more frequently for a precision manufacturing and investment in fields of precision industries such as semiconductor, chemistry and biology, and so forth. Null balance method has been introduced as an alternative of a loadcell. Loadcells have advantages in aspects of low cost and easy manufacturing, but have also the limitation in resolution and sensitivity to environment variations. In this paper, null balance method is explained and the dominant parameters related to system performances are mentioned. Null position sensor, electromagnetic system and controller are investigated. Also, the characteristic experiment is carried out in order to estimate the resolution and the measurement range. In order to overcome the limitation by the drift of position sensor and the performance of controller, double electromagnetic force compensation method is proposed and experimented. After controlling and filtering, the resolution under $\pm$ 1mg and measurement range over 300g could be obtained.

Ne-Ne 레이저의 간섭을 이용한 고정밀 리니어 스케일의 제작에 관한 연구

  • 전병욱;박두원;이명호;한응교
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1991년도 춘계학술대회 논문집
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    • pp.176-194
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    • 1991
  • A study on the Manufactiring of High-Precision Linear Scale by the Use of He-Ne Laser Interference Of late, along with the advancement of procision machining technology, the reauirement of super-precision measurement increases as time goes on, and the precision and accuracy of standard scale which is a basis of procision measurement has been cognized as a oriterion of industrial development in a nation. Up to now, mechanical and chemical methods have been widely employed to carve scale lines on linear scale, and it is impossible for the linear scale manufactured by means of those methods to guarantee the measurement with sub-micron level owing to errors attended with various problems. And the measuring length also bears errors subjected to the influence of surroundings condition, and shows inefficient circumstances in measurement on the ground of the complexity of measuring procedure as well as massive measuring apparatus. Hence in this paper, we described on technology by which we can carve scale lines thru optical method under the condition of laboratory by using rhcoherence of He-Ne two-mode stabilized laser and in turn, put it to practical use as linear scale for the measurment of lengrh. In this researchin the case of setting scale interval to 20 .mu. m, we employed super-precision scale-carving device associated by Ar larser and acoustic optical modulator in lieu of flsahing lamp scale-carving device, and we consequently obtained superior linear scales carved with precision and accuracy of .+-. 0.3 .mu. m.