• 한국공작기계학회논문집
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• 제17권4호
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• pp.112-118
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• 2008

In order to meet the optical performance in the process of the micro lens manufacturing with plastics, it is important to embody accuracy in shape and surface roughness to the intended design. Since it is difficult to machine exactly the mold core of lens fit to the designed shape, in this paper, a simple program using MATLAB is developed for shape correction of the mold core after first machining it. This program evaluates correction parameters(aspheric coefficients and curvature) and generates aspheric NC data for compensating the core surface in prior machining process. The program provides the way to manufacture plastic injection molding lens with aspheric shape of high precision, and is expected to be effective for correction and to shorten the processing time.

• 오토저널
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• 제15권3호
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• pp.89-95
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• 1993

This paper presents the development of CAD system for the design of lens of the Turn Signal Lamp that can model and simulate its optical performance. The system consists of three main modules: skin surface modeling module, inner lens modeling module and optical performance simulation module. Skin surface geometry can be modeled by the input of data file and inner lens can be modeled by the input of only four parameter using its geometric characteristics. Also light distribution pattern, the barometer of optical performance is generated by means of finite ray tracing method. The system display modeled geometry, ray tracing and generated light distribution pattern.

• 한국안광학회지
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• 제17권1호
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• pp.83-89
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• 2012

목적: 본 연구는 아이메이크업에 침지된 소프트콘택트렌즈의 가시광선투과도와 표면 변화를 알아보고자 하였다. 방법: 눈 화장에 사용되는 4가지 종류의 아이메이크업에 침지된 시간에 따라 etafilcon A(이하 HEMA를 기초로 한 하이드로겔 제품)렌즈와 lotrafilcon B(이하 실리콘을 기초로 한 하이드로겔 제품)렌즈의 가시광선투과도 변화를 알아보았다. 1주일간 지속적으로 아이메이크업에 침지된 렌즈를 다목적용액(MPS)을 이용한 세척 후 가시광선 투과도 및 표면 변화를 알아보았다. 결과: 각각의 렌즈를 아이메이크업에 침지시켰을 때 30분 후의 가시광선 투과도는 평균 93.4%(HEMA를 기초로 한 하이드로겔 제품), 90.0%(실리콘을 기초로 한 하이드로겔 제품)로 각각의 대조군의 가시광선투과도(97.8%, 96.4%)와 비교하여 감소하였다. 1주일간 지속적으로 가루 아이섀도우와 마스카라에 침지된 렌즈는 모두 세척 후에도 부착된 아이메이크업 잔여물이 완전하게 제거 되지 않았다. 특히, silicone 계열의 렌즈에서 잔여물이 많은 것으로 나타났는데, 이는 감소된 가시광선 투과도 및 주사전자현미경을 통한 표면 결과로 확인할 수 있었다. 결론: 아이메이크업에 침지된 콘택트렌즈의 경우 렌즈의 소재와 아이메이크업의 소재에 따라 일반적인 세척방법으로는 아이메이크업이 제거되지 않았고 이는 렌즈 표면의 변화와 렌즈의 가시광선 투과도 저하로 나타났다.

• 한국안광학회지
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• 제16권3호
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• pp.247-253
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• 2011

목적: 가열에 의한 플라스틱 렌즈의 변화를 연구하고자 하였다. 방법: -2.00D의 플라스틱 렌즈를 60-100$^{\circ}C$의 온도로 가열한 후 렌즈 굴절력의 변화, 표면 상태의 변화, 투과율의 변화를 조사하였다. 결과: 70$^{\circ}C$에서 1시간, 75$^{\circ}C$에서 10분, 100$^{\circ}C$에서 10초가 렌즈 표면의 변화를 일으키는 시작점으로, 가열온도가 높을수록, 중굴절률렌즈보다 고굴절률렌즈에서 균열이 더 심하게 발생되었다. 투과율은 균열의 정도가 심해짐에 따라 감소되었다. 결론: 70$^{\circ}C$이상의 가열은 렌즈에 변형을 발생시킬 수 있으므로 안경사는 착용자의 작업환경을 고려하여 적절한 렌즈를 추천하여야 하며, 착용자가 안경 사용에 주의를 기울일 수 있도록 안내를 해야 할 것이다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.879-880
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• 2010

• 대한방사선기술학회지:방사선기술과학
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• 제45권4호
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• pp.313-320
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• 2022

Both angiography and interventional procedures accompanied by angiography provide many diagnostic and therapeutic benefits to patients and are rapidly increasing. However, unlike general radiography or computed tomography using the same X-ray, the amount of radiation is quite high, but the dose range can vary considerably for each patient and operator. The high sensitivity of the lens to radiation during cerebral angiography and neurointervention is already well known, and although there are many related studies, it is insufficient to easily reduce radiation in diagnosis and treatment. In this situation, in particular, by adding three-dimensional rotational angiography (3D-RA) to the existing two-dimensional (2D) angiography, it is now possible to make an accurate diagnosis. However, since this 3D-RA acquires images through projection of more radiation than before, the exposure dose of the lens may be higher. Therefore, we tried to analyze whether the radiation dose of the lens can be reduced by moving the lens out of the field range by adjusting the table height and magnification ratio during the examination using 3D-RA. The surface dose was measured using a rando phantom and a radiophotoluminescent glass dosimeter (PLD) and the radiation dose was compared by adjusting the table height and magnification ratio based on the central point. As a result, it was found that the radiation dose of the lens decreased as the table height increased from the central point, that is, as the lens was out of the field of view. In conclusion, in 3D-RA, moving the table position of about 2 cm in height will make a significant contribution to the dose reduction of the lens, and it was confirmed that adjusting the magnification ratio can also reduce the surface dose of the lens.

• 한국기계가공학회지
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• 제19권2호
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• pp.69-74
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• 2020

In this study, we proposed a method for surface profiling aspheric lens molds using a precision displacement sensor with a spatial scanning mechanism. The precision displacement sensor is based on the confocal principle using a broadband light source, providing a 10 nm resolution over a 0.3 mm measurable range. The precision of the sensor, depending on surface slope, was evaluated via Allan deviation analysis. We then developed an automatic surface profiling system by measuring the cross-sectional profile of a lens mold. The precision of the sensor at the flat surface was 10 nm at 10 ms averaging time, while 200 ms averaging time was needed for identical precision at the steepest slope at 25 deg. When we compared the measurement result of the lens mold to a commercial surface profiler, we found that the accuracy of the developed system was less than 90 nm (in terms of 3 sigmas of error) between the two results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1497_1498
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• 2009

This paper presents the simulation of micro-lens arrays based on dry and wet etching technique. Code V (Optical Research Associates Ltd) simulation was performed to extract optimal design parameters of a Micro-Lens Array(MLA). Thickness of UV adhesive, wavelength of laser source, curvature, and shape of lens surface were chosen for the design parameters. The simulation results showed that focal length of a MLA decreased with the increase of UV adhesive thickness. And the focal length depended on shape of lens surface and length of laser source.

• 한국기계가공학회지
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• 제2권1호
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• pp.63-68
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• 2003

The aspherical lenses are used as objective lens of optical pickup. To examine the design factor the sample product is made before manufacturing of injection mould of lens. The optimum cutting condition of PMMA lens sample with ultra precision SPDT, the roam spindle speed, the depth of cut, the feedrate are found. The demanded surface roughness 100m Ra, aspherical form error $0.5{\mu}m$ P-V for aspherical lens of optical data storage device are satisfied.

• 한국안광학회지
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• 제5권1호
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• pp.199-203
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• 2000

콘택트렌즈 표면의 미세한 흠집이나 뜯김 등의 흠과 콘택트렌즈 edge부분의 연마상태나 파손여부를 식별하기 위해서는 배율이 커야하며, 또한 왜곡수차와 색수차가 제거되어야만 한다. 본 연구에 사용된 콘택트렌즈 분석기 "CONTACT LENS ANALYZER CA-20"은 표면검사에 적합한 16배의 큰 배율과 왜곡수차가 우선 제거된 우수한 분석기라고 말할 수 있다.