Error analysis of aspheric surface with reference datum

Large aspheric mirrors with diameter over 300 millimeters with high surface accuracy are wildly used in many areas such as astronomical telescopes. Interferometers are widely used in profile measurement of optical flat and sphere. However, standard reference aspheric surface which is necessary for this method is difficult to make. Scanning defletometry based on ESAD (Extended Shear Angle Difference) is used to measure ultra-precise large near-flat and slight curved optical surface with the accuracy of sub-nanometer. However, it is not possible for it to measure aspheric surface because of the limitation of the measuring range of autocollimators. We proposed a new measuring method to scan the surface of a large aspheric optical surface using autocollimator with rotatable optical devices fixed on linear motion stage. To eliminate the influence of the pitching error of the scanning stage, we use two mirrors reflecting laser comes from autocollimator, which have the same effect with a pentaprism used in ESAD. To enlarge the measuring range of the autocollimator, we use a rotatable mirror to fit the changes of the slope of the mirror surface under measurement. The error analysis of the method is done. Measurement of an optical flat mirror and a sphere mirror with diameter of 50 mm and biggest slope of 6000 arc-second are done. The rotatable optical devices that we designed are proved effective on eliminating the pitching error of the moving stage.

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Error analysis for aspheric surface testing system

10.1117/12.2034884 ◽

2013 ◽

Author(s):

Jie Feng ◽

Chao Deng ◽

Tingwen Xing

Keyword(s):

Error Analysis ◽

Testing System ◽

Aspheric Surface ◽

Surface Testing

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Aspherical Surface Contact Detection Error Analysis

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.690-693.3213 ◽

2013 ◽

Vol 690-693 ◽

pp. 3213-3217

Author(s):

Hai Hua Xu ◽

Yu Zhang ◽

Xiao Guang Xia ◽

Zi Wei Wang

Keyword(s):

Error Analysis ◽

Detection Methods ◽

Precision Machining ◽

Aspheric Surface ◽

Precision Manufacturing ◽

Detection Technology ◽

Key Factor ◽

Ultra Precision ◽

Processing Accuracy ◽

The Uk

Aspheric detection technology has always been the key factor which affects the further enhance of aspheric precision manufacturing. Without high-precision detection methods and instruments to fit processing accuracy, aspherical precision machining and ultra-precision machining is difficult to achieve. A contact measurement of aspheric surface detection technology and its error analysis are mainly introduced in this paper, and testing equipment is the UK Taylor Hubson profilometer with instrument precision 0.2μm and measure the caliber 200mm.

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Machining mode and error analysis in non-axisymmetric aspheric surface grinding

10.1117/12.783174 ◽

2007 ◽

Cited By ~ 1

Author(s):

Zhen-zhong Wang ◽

Yin-biao Guo ◽

Hao Huang ◽

Jiang Gou

Keyword(s):

Error Analysis ◽

Surface Grinding ◽

Aspheric Surface

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Simulation and error analysis of non-null interferometry for measuring high-order aspheric surface parameter errors

10.1117/12.2600712 ◽

2021 ◽

Author(s):

Yiming Liu ◽

Xin Tao ◽

Yao Hu ◽

Qun Hao

Keyword(s):

Error Analysis ◽

High Order ◽

Aspheric Surface ◽

Surface Parameter

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The O–C diagrams of minor planets − a new approach to modelling the rotation

International Astronomical Union Colloquium ◽

10.1017/s0252921100031407 ◽

1999 ◽

Vol 173 ◽

pp. 185-188

Author(s):

Gy. Szabó ◽

K. Sárneczky ◽

L.L. Kiss

Keyword(s):

Error Analysis ◽

Time Dependence ◽

Theoretical Work ◽

Minor Planet ◽

Minor Planets ◽

New Approach ◽

Preliminary Results ◽

Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

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Error Analysis in Neuropsychological Assessment of Verbal Memory and Learning

European Journal of Psychological Assessment ◽

10.1027/1015-5759.11.1.21 ◽

1995 ◽

Vol 11 (1) ◽

pp. 21-28 ◽

Cited By ~ 5

Author(s):

Dietmar Heubrock

Keyword(s):

Error Analysis ◽

Verbal Memory ◽

Verbal Learning ◽

Learning Disorders ◽

Memory And Learning ◽

Auditory Verbal Learning Test ◽

Additional Information ◽

Auditory Verbal Learning ◽

Accurate Picture ◽

Learning Test

Performance on a German version of the Rey Auditory-Verbal Learning Test (AVLT) was investigated for 64 juvenile patients who were subdivided in 6 clinical groups. In addition to standard evaluation of AVLT protocols which is usually confined to items recalled correctly, an error analysis was performed. Differentiating between total errors (TE), repetition errors (RE), and misnamings (ME), substantial differences between clinical groups could be demonstrated. It is argued that error analysis of verbal memory and learning enriches the understanding of neuropsychological syndromes, and provides additional information for diagnostic and clinical use. Thus, it is possible to gain a more accurate picture so that patients can be appropriately retrained, and research into the functional causes of memory and learning disorders can be intensified.

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