• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2009.04a
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• pp.41-48
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• 2009

Laser diode is used as a crucial part for minimization of terrestrial 3D Laser Scanner. But it has certain limitations such as oval beam shape and inevitable astigmatism. In order to realize a parallel light with beam divergence below 1 mrad, These problems of laser diode can be solved through beam shaping by Pinhole and Aperture. Finally, this study could materialize a collimated beam with 0.3 mrad beam divergence angle and 3mm diameter, that performance and checked by using real manufacture.

• Tunnel and Underground Space
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• v.17 no.3 s.68
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• pp.165-174
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• 2007

The technique, which reproduces the figures of objects from measured data of the objects using 3-D laser scanner, is called reverse engineering. Recently, research studies into applications of reverse engineering to rock engineering are increasing in number, in the discontinuity surveys for rock slopes out of man's reach, or rapid discontinuity surveys for wide range areas. For analysis of discontinuity using reverse engineering, a program for processing point clouds data from the 3-D laser scanner, for sampling from these point clouds data, and finally analyzing the discontinuity is needed. However, existing programs rarely have sufficient functions to properly analyze the discontinuities. In this study, a program was developed, which can automatically sample discontinuities from the point clouds data which measured in a rock slope using a 3-D laser scanner, and which can also undertake statistical analysis of the discontinuities. This developed program was verified by the application of discontinuity surveys in a rock slope and a tunnel. By undertaking the discontinuity survey using a 3-D laser scanner and the developed program, the feasibility and rapidity of such surveys is expected to improve in areas out of man's reach in geotechnical surveys. Taking into consideration the fact that the international level of related techniques is at a rudimentary stage, the possibility of prior occupation of a broad market is also expected.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.861-862
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• 2012

• Laser Solutions
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• v.16 no.4
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• pp.17-23
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• 2013

The research for the development of roll-to-roll printing process is actively underway on behalf of the existing semiconductor process. The roll-to-roll printing system can make the electronic devices to low-cost mass production. This study is performed for developing the manufacturing technology of the printing roll used in the printing process of electronic devices. The indirect laser engraving technology is used to create printable roll and the printable roll is made out of the chrome coated roll after coating copper and polymer on the surface of steel roll, ablating the polymer on the surface of roll and etching the roll. The 3 dimensional laser scanner and roll rotating systems are constructed and the system control program is developed. We have used the fiber laser of 100 W grade, the 3 dimensional laser scanner and the 3 axes moving stage system with a rotating axis. We have found the optimal conditions by performing the laser patterning experiments and can make the minimum line width of $24{\mu}m$ by using the developed 3 dimensional laser scanner system.

• Laser Solutions
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• v.14 no.2
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• pp.1-7
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• 2011

The latest trends of vehicle technology development are fuel efficiency improvement, body designs declining air resistance and lightweight of materials. Especially, as lightened weight of materials makes engine efficient so that vehicles keep the best performance, it is the best way to protect the environment and reduce fuel consumption. In this study, we conducted laser welding by using 3-dimension remote scanner that is 5J32 aluminium alloy. Furthermore, conduction experiment that was 3 times repeated for changing factors such as observing angle, laser power and welding speed. we observed exterior and cross section of weled part and tensile strength. When increasing laser power and decreasing laser speed, tensile strength increased. In order to evaluate factors that affect tensile strength qualitatively we conducted ANOVA. We assumed that the factors are observing angle, laser power and welding speed. Then we found that laser power and laser speed affect tensile strength. We conducted evaluation of weldability of aluminium alloy by above ways.

• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.1
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• pp.54-63
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• 2009

Various methods have been employed for acquiring beach surface data, which are used to monitor shoreline changes due to beach erosion. This study explores the possibility of constructing and implementing a surface model of beach using data acquired with a terrestrial laser scanner and RTK-GPS. Digital images and three-dimensional data of beach areas acquired at 20 cm intervals using a laser scanner were used to create a digital surface model covered with digital image. Seven months later, the beach area was surveyed using an RTK-GPS, and another beach model was constructed using the data collected with an accuracy of 1.9 cm. The use of a terrestrial laser scanner is expected to ensure acquisition of good quality results and help deal with seasonal changes in beach areas. Because readings obtained with the RTK-GPS are dependent on the number of sampling points in beach model, difficulties are encountered when fixing the survey points. However, RTK-GPS could be used to implement a three-dimensional model by correcting the hidden parts in images obtained using a terrestrial laser scanner. Therefore, an RTK-GPS and a terrestrial laser scanner can be used in combination to obtain more precise data for the construction of beach model data.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1998.11a
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• pp.99-104
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• 1998

3차원 형상정보 추출기술은 3D스캐너에 활용되어 실물의부터 3차원 모델을 생성하는데 사용되고 있다. 현재까지 주로 사용되는 기술은 레이저광을 이용하여 3차원 모델을 만드는 기술과 스테레오기법에 의한 방법들이 사용되고 있었다. 본 논문에서는 모아레기법을 사용하여 영상정보를 프레임단위로 해석함으로써 3차원 형상 정보를 빠른 시간내에 추출하고, 수평 360도 방향에 대해서는 3∼4프레임을 해석하여 형상정보를 통합하였고, 이로부터 3차원 모델을 생성하였다. 모아레기법의 장점은 3차원 정보를 레이저기법보다 정밀하게 추출할 수가 있었다. 본 논문에서는 모아레영상을 해석하여 3차원 형상정보를 추출하는 방법, 추출된 3차원 형상으로부터 메쉬최적화와 텍스춰매핑(Texture Mapping)을 사용하여 3차원 모델을 형성하는 방법들을 제안한다.

• Water for future
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• v.55 no.3
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• pp.70-77
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• 2022

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.242-247
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• 2017

Over- and under-excavation are factors that increase construction cost of tunnels, which makes management essential. Total stations have been used for tunnel surveying because GNSS is difficult to use in tunnels. However, it takes much time to acquire data using total stations. In this study, a total station was integrated with a 3D laser scanner and used for tunnel surveying in Namyangju-si, Gyeonggi-do. The scanning total station reduced the work time compared to the conventional method. Furthermore, reports were effectively generated for overbreak and underbreak for each section and compared with the design. In addition, we could analyze both the cross section and scanned area effectively by using the scanning data. This method can improve the efficiency of tunnel surveying work by combining the advantages of a conventional total station and a 3D laser scanner.

• Electronics and Telecommunications Trends
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• v.12 no.6 s.48
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• pp.15-23
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• 1997

본 논문에서는 실존하는 물체의 3차원 모델을 만드는 방법들 중에서 물체로부터 직접 정보를 얻어내어 매우 사실적인 3차원 모델을 제작하는 기법들에 대한 현재까지의 기술들에 대해 분석해보고 앞으로의 발전 방향에 대한 전망을 해보았다. 실제 물체의 데이터를 얻어내는 방법은 크게 세가지로 나뉘며 3차원 디지타이저, 3차원 레이저 스캐너 그리고 사진을 이용하는 방법이 있다. 이러한 방법들이 기초적인 요구 사항을 만족하고 있는지와 핵심기술은 어떠한 것들인지를 분석해본다.