• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2003.04a
• /
• pp.255-259
• /
• 2003

Moire topography method isa well-known non-contacting 3-D measurement method as afast non-contact test for three-dimension shape measuring method. Recently, it's important to study the automatic three-dimension measurement by moire topography because it is frequently applied to the reverse engineering , the medical , the entertainment fields. Three-dimension measurement using projection of moire topography is very attractive because of its high measuring speed and high sensitivity. In this paper, the classical moire method is computerized-so called digital moire when a virtual grating pattern is projected on a surface, the captured image by the CCD camera has three-dimension information of the objects. The moire image can be obtained through a simple image processing and a reference grating pattern. and it provides similar results without physical grating pattern. digital projection moire topography turn out to be very effective for the three-dimension measurement of objects. Using different N-bucket algorithm method of digital projection moire topography is tested to measuring object with the 2-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding measurement errors that decreased more by using the four-three step algorithm method instead of the same step in the phase shifting of different pitch.

• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.6 no.4
• /
• pp.39-45
• /
• 1997

Shadow moire topography has been used as a noncontact method for measuring the 3-D shapes of objects. The moire fringes are results from the superposition of a master grating and its shadow projected on the surface of an object. But in case of the classical shadow moire method, in general, the resolution is a few tenths of millimeter. It is difficult to use a phase -shifting method in shadow moire because it is impossible to obtain uniform phase shifts on the whole field. But in this study , We introduce a phase-shifting method to improve the resolution of the classical shadow moire method. This method is based on the fact that if the depth of object is much less than the distance between the observer and the master grating, the phase shifts are almost uniform on the whole field area. Finally, we applied this new phase-shifting method to the measurement of the 3-D shape of a coin.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.199-202
• /
• 2002

Moire topography method is a well-known non-contacting 3-D measurement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using digital projection moire topography is very attractive because of its high measuring speed and high sensitivity. In this paper, using different N-bucket algorithm method of digital projection moire topography is tested to measuring object with the 2$\pi$-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding measurement errors that decreased more by using the flour-three step algorithm method than the same step in the phase shifting of different pitchs.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.292-295
• /
• 2003

Moire topography method is a well-known non-contacting 3-D measurement method. the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using digital projection moire topography is very attractive because of its high measuring speed and high sensitivity. In this study, digital two-wavelength phase shilling moire is applied to the entertainment fields. recently. as promoting the growth of the VR-Game, display devices which attract public attention such as HMD or Projector are being appeared in order to deliver effectively the absorption sense. this study realized the Auto-calibrating system for arbitrary display surface using digital moire method which satisfied the shape measurement of display surface and the request of FOV(Field of View) output. also when large screen wasn't prepared, this auto-calibrating system was applied to enjoy games or movies at home with a projector and walls

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2001.04a
• /
• pp.49-52
• /
• 2001

Moire topography method is a well-known non-contacting 3-D measurement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using projection moire topogrphy is very attractive because of it s high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection moire topography tested to measuring object with the $2\pi$-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the $2\pi$-ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured objects.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.31 no.6 s.261
• /
• pp.659-664
• /
• 2007

$Moire\'{e}$ interferometry is a useful technique to assess the reliability of electronic package because $Moire\'{e}$ interferometry can measure the whole-field and real-time deformations. The shear strain of a small crack site is important to the reliability assessment of electronic package. The optical limitation of $Moire\'{e}$ interferometry makes ambiguous the shear strain of a small area. An atomic force microscope (AFM) is used to measure the profile of a micro site. High resolution of AFM can apply to the $Moire\'{e}$ technique. AFM $Moire\'{e}$ technique is useful to measure the shear strain of a small area. In this research, the method to accurately measure the deformation of a small area by using AFM $Moire\'{e}$ is proposed. A phase-shifting method is applied to improve the resolution of AFM $Moire\'{e}$.

• Journal of Korea Multimedia Society
• /
• v.5 no.3
• /
• pp.263-271
• /
• 2002

In this paper, we propose a new smoothing method for removing moire patterns using analysis of halftone patterns interference. The proposed method can determine a strength of moire patterns by using gray values of pixels and the size of smoothing mask for moire region is adjusted adaptively according to the strength of moire patterns. Therefore it can remove moire patterns effectively and preserve meaningful high frequencies well, such as edges and textures. The proposed method only refer to predefined lookup table to determine the strength of moire patterns, so it is more efficient than a previous work based on FFT of subblock. It could be applied to field of various multimedia applications that deal with color prints.

• Journal of Society of Preventive Korean Medicine
• /
• v.20 no.1
• /
• pp.75-87
• /
• 2016

Objectives : This study aims to classify and analyze literature related to moire topography, as a diagnostic device of Korean medicine, discuss research trends and major results, and demonstrate the value of moire topography. Methods : To investigate moire topography research trends, Korean keywords that signify 'moire' were searched in a Korean journal search engine. Initially, 2,988 papers were found in the research, and, after classifying them and removing those that are duplicate in other databases, only 37 papers were applicable for the literature review in this study. To analyze research trends, the 37 papers were analyzed based on the publication year, research field, journal, and research type, and, clinical articles were classified based on the diagnosis purpose, subject characteristics, diagnosis method, test method, and test result, for analysis. Results : Moire topography research in South Korea was first conducted in 1995 and most active in 2003, mostly in the field of Korean medicine. In the journal analysis, The Journal of Korea CHUNA Manual Medicine for Spine & Nerves published the highest number of papers, most of which were clinical articles and the rest were literature review. And, in the analysis of clinical papers, based on the diagnosis purpose, muscle somatotype measurement was most common, followed by diagnosis of scoliosis. In terms of subjects, most studies focused on elementary, middle, and high school students, and, in terms of the diagnosis method, other tests were used in most studies. The analysis of moire topography methods showed that most studies measured the shoulder, back, and hip, and the most common measurement method in the studies measured the difference in contour lines on the left and right by designating a central line of the body. In terms of the result, most moire topography brought about significant diagnosis results, and many studies demonstrated its use for musculoskeletal diseases in particular. Conclusions : Moire topography is believed to be highly significant for diagnosis and treatment of musculoskeletal diseases and further research will be needed to support it.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.04a
• /
• pp.96-100
• /
• 1997

The shadow moire is one of the optical techniques which is able to give contour lines of an object with respect to a master grating plane. The moire patterns are issued from the superposition of a master grating and its shadow projected on the surface of an object. In case of the classical shadow moire method, the sensitivity was a few tenths millimeters. generally, it is difficult to use a phase shift method in shadow moire because it is impossible to obtain uniform phase shifts on the whole field. But in this study we use the fact that if the depth of object is much less than the distance between the observer and the master grating, and the object is displaced perpendicularly to the grating plane, phase shifts are almost uniform. Finally we obtained a better resolution by using a phase shift procedure and applied the phase shifting shadow moire to three dimensional shape measurement.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.10a
• /
• pp.220-223
• /
• 1997

Moire topography method is a well-known non-contacting 3-D measuement method. Recently, the automatic 3-D measurement by moire topography has been required since the method was frequently applied to the engineering and medical fields. 3-D measurement using projection moire topography is very attractive because of it's high measuring speed and high sensitivity. In this paper, using two-wavelength method of projection moire topography tested to measuring object with the 2x-ambiguity problem. Experimental results prove that the proposed scheme is capable of finding absolute fringe orders, so that the 2x-ambiguity problem can be effectively overcome so as to treat large step discontinuities in measured objects.