• 한국생산제조학회지
• /
• 제18권3호
• /
• pp.285-293
• /
• 2009

Thermal infrared cameras have been conducted actively in various application areas, such as military, medical service, industries and cars. Because of their characteristic of sensing the radiant heat emitted from subjects in the range of long-wavelength($3{\sim}5{\mu}m$ or $8{\sim}12{\mu}m$), and of materializing a vision system, when general optics materials are used, they don't react to the light in the range of long-wavelength, and can't display their optic functions. Therefore, the materials with the feature of higher refractive index, reacting to the range of long-wavelength, are to be used. The kinds of materials with the characteristic of higher refractive index are limited, and their features are close to those of metals. Because of these metallic features, the existing producing method of optical systems were direct manufacturing method using grinding method or CAD/CAM, which put limit on productivity and made it difficult to properly cope with the increasing demand of markets. GASIR, a material, which can be molded easily, was selected among infrared ray optics materials in this study, and the optical system was designed with two Aspheric lenses. Because the lenses are molded in the environment of high temperature and high pressure, they require a special metallic pattern. The metallic pattern was produced with materials with ultra hardness that can stand high temperature and high pressure. As for the lens mold, GMP(Glass Molding Press) of the linear transfer method was used in order to improve the productivity of optical systems for thermal infrared cameras, which was the goal of this paper.

• 한국광학회지
• /
• 제28권5호
• /
• pp.241-249
• /
• 2017

본 논문에서는 $7.7{\mu}m$에서 $12.8{\mu}m$ 파장 대역에 적용 가능한 비냉각 열상장비 광학계를 설계 및 분석 하였다. 최적화 과정을 통하여 설계된 원적외선 광학계의 유효초점거리는 5.44 mm를 가지며, 4면의 비구면과 2면의 회절면을 포함하였다. 광학계의 F/수는 F/1.2로 설정하였고, 시야각은 $90^{\circ}{\times}67.5^{\circ}$가 되도록 하였다. 회절면이 적용된 hybrid 렌즈를 이용하여 보다 효율적으로 고차 수차가 보정되도록 하였고, 이때 발생되는 회절 특성은 scalar 회절 효율을 이용하여 평가하였다. 또한 hybrid 렌즈에서 발생되는 회절 현상에 의한 통합 회절효율을 예측하고 배경잡음에 의한 MTF 저하를 고려하였다. 원적외선 광학계의 온도 변화에 따른 보상은 광학식 비열화를 이용하여 광학계의 MTF 성능이 초점 심도 내에서 유지되도록 하였다. 결론적으로 비냉각 열상장비에 효율적으로 적용 가능한 광학설계 결과를 얻었다.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2002년도 춘계학술대회 논문집
• /
• pp.191-194
• /
• 2002

In optical pick-up, optical components such as objective lens, collimator, mirror, laser diode and photo diode are mounted on the pick-up base. These components must keep their original position during operation for proper transmittance of information from laser diode to optical disk and back to photo diode. However, micro thermal deformation of pick-up base which is induced by thermal environment during operation can deteriorate the performance of optical pick-up. Therefore, it is important to measure and analyze the thermal deformation behavior of pick-up base under thermal environment. In the present study, a measurement system using holographic interferometry was designed to measure micro thermal deformation of pick up base. The measurement system was verified by using the deformation of cantilever with prescribed motion actuated by PZT with 1 nm resolution. Interferometric measurement was compared quantitatively with that induced by PZT actuator. Finally, micro thermal deformation of pick-up base under actual thermal environment was measured using the present holographic interferometry and the results were analysed.

• 한국산업정보학회논문지
• /
• 제20권1호
• /
• pp.57-62
• /
• 2015

최근 인체에서 방출되는 적외선을 감지하여 질병부위를 진단하는 의료기기로써 체열촬영이 가능한 열화상카메라가 활용되고 있다. 본 연구에서는 칼코지나이드 소재 적외선 성형렌즈를 채용한 열화상카메라 시제품을 제작하고, 열영상 분석을 통해 체열진단 장비로써의 시제품 성능을 검증하였다. 열화상카메라 시제품은 $20{\sim}50^{\circ}C$에서 체열이 촬영됨을 확인 하였고, 온도분해능(NEDT) 측정결과 87.7mK의 우수한 결과를 나타냈다. 이를 통해 칼코지나이드 성형렌즈를 채용한 열화상카메라 시스템이 체열진단을 위한 의료기로 사용가능함을 확인 하였다.

• 한국전기전자재료학회논문지
• /
• 제26권9호
• /
• pp.641-645
• /
• 2013

Chalcogenide glass has superior property of optical transmittance in the infrared region. Glass made using Ge-Se how many important optical applications. We have determined the composite formular of $Ge_{0.25}Se_{0.75}$ to be the GeSe chalcogenide glass composition appropriate for IR lenses. Also, the optical, thermal and physical characteristics of chalcogenide glass depended on the composition ratio. GeSe bulk sample is produced using the traditional melt-quenching method. The optical, structural, thermal and physical properties of the compound were measured by using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Differential scanning calorimeter (DSC), and Scanning electron microscope (SEM) respectively.

• Tribology and Lubricants
• /
• 제25권4호
• /
• pp.207-216
• /
• 2009

Friction tests were carried out in order to investigate the effects of temperature on the friction and wear behaviors between a PMMA film and a fused silica lens using a microtribometer. The friction forces on the PMMA film were measured under atmospheric condition as the temperature of the film was increased from 300 K to 443 K. The contact area between the film and the lens was observed. The tribological characteristics of the film were significantly changed as the temperature increased. The changes were discussed with the change of the film state from glassy to viscous flow. In addition, the results showed that the friction behavior can be varied with the thermal history of the PMMA film. Residual solvent in the PMMA film could emerge to the PMMA surface due to an additional heating and the solvent on the film surface decreased the friction force.

• 대한화학회지
• /
• 제40권6호
• /
• pp.385-393
• /
• 1996

Poly(2-hydroxyethylmethacrylate, HEMA)는 contact lens 재료물질로 사용되고, 물을 약 45퍼센트 포함하여 수화겔(hydrogel)을 만들 수 있는 고분자이다. Poly(HEMA)와 아미노산(alanine, arginine, methionine, proline, glycine, serine, lysine)과의 상호작용력을 DSC와 TGA 열분석법으로 측정한 결과 lysine, arginine, alanine의 결합성이 큼을 알 수 있었다.

• 한국융합학회논문지
• /
• 제9권6호
• /
• pp.203-207
• /
• 2018

본 연구는 초점거리가 24mm 인, 대기투과 특성이 좋은 $3{\sim}5{\mu}m$ 파장대역의 적외선의 상을 결상할 수 있는 렌즈계의 설계 개발에 관한 것이다. 설계는 상용 설계 프로그램인 CodeV를 사용하였고, 색수차, 구면수차 및 왜곡 제거에 가중치를 가지는 최적화를 진행하였다. 설계되어진 렌즈계는 Si와 Ge로 구성된 2매의 렌즈로 이루어져 있는데, 각각의 렌즈는 한 면이 비구면으로 이루어져 있다. 그리고 이 광학계는 선폭 20lp/mm에서는 MTF값이 0.40, 선폭 29lp/mm에서는 MTF값이 0.25인 특성의 분해능을 갖게 되었다. 이 광학계는 $25{\mu}m$ pixel의 $206{\times}156$ 어레이 및 $17{\mu}m$ pixel의 $320{\times}240$ 어레이 적외선 검출소자를 사용하는 MWIR용 열화상 카메라에 적용할 수 있는 성능을 가진 것으로 판단된다.

• 천문학회보
• /
• 제39권1호
• /
• pp.53.2-53.2
• /
• 2014

IGRINS, the Immersion GRating INfrared Spectrometer, is a near-infrared wide-band high-resolution spectrograph jointly developed by the Korea Astronomy and Space Science Institute and the University of Texas at Austin. IGRINS employs three HAWAII-2RG focal plane array (FPA) detectors. The mechanical mounts for these detectors serves a critical function in the overall instrument design: Optically, they permit the only positional compensation in the otherwise "build to print" design. Thermally, they permit setting and control of the detector operating temperature independently of the cryostat bench. We present the design and fabrication of the mechanical mount as a single module. The detector mount includes the array housing, a housing for the SIDECAR ASIC, a field flattener lens holder, and a support base. The detector and ASIC housing will be kept at 65 K and the support base at 130 K. G10 supports thermally isolate the detector and ASIC housing from the support base. The field flattening lens holder attaches directly to the FPA array housing and holds the lens with a six-point kinematic mount. Fine adjustment features permit changes in axial position and in yaw and pitch angles. We optimized the structural stability and thermal characteristics of the mount design using computer-aided 3D modeling and finite element analysis. Based on the computer simulation, the designed detector mount meets the optical and thermal requirements very well.

• 한국재료학회지
• /
• 제33권10호
• /
• pp.414-421
• /
• 2023

Infrared radiation (IR) refers to the region of the electromagnetic radiation spectrum where wavelengths range from about 700 nm to 1 mm. Any object with a temperature above absolute zero (0 K) radiates in the infrared region, and a material that transmits radiant energy in the range of 0.74 to 1.4 um is referred to as a near-infrared optical material. Germanate-based glass is attracting attention as a glass material for infrared optical lenses because of its simple manufacturing process. With the recent development of the glass molding press (GMP) process, thermal imaging cameras using oxide-based infrared lenses can be easily mass-produced, expanding their uses. To improve the mechanical and optical properties of commercial materials consisting of ternary systems, germanate-based heavy metal oxide glasses were prepared using a melt-cooling method. The fabricated samples were evaluated for thermal, structural, and optical properties using DSC, XRD, and XRF, respectively. To derive a composition with high glass stability for lens applications, ZnO and Sb₂O₃ were substituted at 0, 1, 2, 3, and 4 mol%. The glass with 1 mol% added Sb₂O₃ was confirmed to have the optimal conditions, with an optical transmittance of 80 % or more, a glass transition temperature of 660 ℃, a refractive index of 1.810, and a Vickers hardness of 558. The possibility of its application as an alternative infrared lens material to existing commercial materials capable of GMP processing was confirmed.