• 제목/요약/키워드: Opaque Substrate

검색결과 13건 처리시간 0.021초

나노 스테레오리소그래피 공정을 이용한 불투명 기판에서의 3차원 마이크로 형상 제작 방법에 관한 연구 (Direct Patterning of 3D Microstructures on an Opaque Substrate Using Nano-Stereolithography)

  • 손용;임태우;하철우;양동열;정병제;공홍진
    • 한국정밀공학회지
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    • 제27권10호
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    • pp.93-99
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    • 2010
  • A nano-stereolithography is the direct patterning process with a nanoscale resolution using twophoton absorption induced by a femtosecond laser. However, in the majority of the works, the fabrication of 3D microstructures have been done only onto transparent glass due to the use of an oil immersion objective lens for achieving a high resolution. In this work, the coaxial illumination and the auto-focusing system are proposed for the direct patterning of nano-precision patterns on an opaque substrate such as a silicon wafer and a metal substrate. Through this work, 3D polymer structures and metallic patterns are fabricated on a silicon wafer using the developed process.

금속하부구조물이 도재의 색조에 미치는 영향에 대한 분광측색분석 (SPECTROPHOTOMETRIC ANALYSIS OF THE INFLUENCE OF METAL SUBSTRATE ON THE COLOR OF CERAMIC)

  • 이수옥;우이형;최대균;권긍록
    • 대한치과보철학회지
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    • 제41권2호
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    • pp.148-159
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    • 2003
  • Statement of problem Metal-ceramic restorations have been used extensively by dental clinicians for nearly 40 years. Strength an functional ability of metal-ceramic restorations are proved to be satisfying, However esthetics and biocompatibility of metal alloy which is used in metal-ceramic restoration is not ideal. Using pure gold as an alternative, have advantage of esthetics, biocompatibility over conventional metal alloy. But there had been little article which studied on the color effect of pure gold on fual porcelain color. Purpose The purpose of this study was to spectrophotometrically evaluate the difference between color of metal alloy(Au-Pt, Ni-Cr) and pure gold, during color masking procedure with opaque porcelain and to analyze the differences, Material and Methods Three types of metal - base metal(Ni-Cr), high gold alloy(Au-Pt), pure gold(GES) - specimen were fabricated 1cm in diameter. Four steps were established - after finishing, after pre-coditioning, after application of first opaque porcelain(0.08mm in thickness), after application of second opaque porcelain(0.15mm in thickness)- and tested color with spectrophotometer every each steps and analyzed with $CIEL^*a^*b^*$ color order system. One-Way ANOVA test was used to and out if there were significant differences between groups tested and Shaffe multiple comparison was used to identify where the differences were. Results 1. After finishing and pre-conditioning, pure gold(GES) group showed most high values in $L^*,a^*,b^*$. 2. After application of first opaque porcelain(0.08mm in thickness), after application of second opaque porcelain(0.15mm in thickness), pure gold(GES) group showed the least difference in $L^*,a^*,b^*$ values and the lowest ${\Delta}E$ value(${\Delta}E$=0.63). 3. After application of first opaque porcelain and after application of second opaque porcelain differences that were significant (P<0.05) between groups were found only in $a^*$ values. 4. Base metal alloy group showed the lowest $a^*$ value in test after application of first opaque porcelain and the highest value in test after application of first opaque porcelain Conclusion Pure gold group and high gold group showed higher $a^*$ values than base metal group when tested after 0.08mm thickness of opaque porcelain was applied and pure gold group showed much similar $L^*,a^*,b^*$ values between 0.08mm thickness and 0.15mm thickness of opaque porcelain. This meant that pure gold was more easily masked by opaque porcelain than the other two groups.

OBSERV ATION OF MICRO-STRUCTURE AND OPTICAL PROPERTISE OF TITANIUM DIOXIDE THIN FILMS USING OPTICAL MMEHODS

  • Kim, S.Y.;Kim, H.J.
    • 한국표면공학회지
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    • 제29권6호
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    • pp.788-796
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    • 1996
  • $TiO_2$ films prepared by RF magnetron sputtering, electron beam evaporation, ion assisted deposition (IAD) and sol-gel method are prepared on c-Si substrate and vitreous silica substrate respectively. From the transmission spectra of $TiO_2$ films on vitreous silica substrate in the spectral region from 190 nm to 900 nm, k($\lambda$) of $TiO_2$ is obtained. Using k($\lambda$) in the interband transition region the coefficients of the quantum mechanical dispersion relation of an amorphous $TiO_2$ and hence n($\lambda$) including the optically opaque region of above fundamental transition energy are obtained. The spectroscopic ellipsometry spectra of $TiO_2$ films in the spectral region of 1.5-5.0eV are model analyzed to get the film packing density variation versus i) substrate material, ii) film thickness and iii) film growth technique. The complex refractive index change of these $TiO_2$ films versus water condensation is also studied. Film micro-structures by SE modelling results are compared with those by atomic force microscopy images and X-ray diffraction data.

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도기유의 표면장력이 Pinhole 현상에 미치는 영향 (Influence of Surface Tension on Pinhole Phenomenon of Earthen Ware Glazes)

  • 지응업;이경재
    • 한국세라믹학회지
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    • 제13권3호
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    • pp.3-12
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    • 1976
  • The corelation between surface tensions and surface appearances of SK O5a opaque glazes for earthen wares were investigated. The surface tension values were theoretically calculated by using Dietzel's factors of constituent oxides of glaze. The surface appearances of glazes, especially the pinhole phenomena were strongly effected by the surface tension values showing the following general tendencies: (1) In the range of 305±3 dynes/cm of surface tensions, glazes showed almost no pjnholes. (2) In the range of surface tensions less than 300 dynes/cm, the large numbers of small pinholes or eggshell textures were observed. (3) In the range of surface tensions higher than 310 dynes/cm, large and deep pinholes were observed. (4) The contact angles of glazes on the wall tile body substrate are in the good proportional agreement with the surface tension values calculated by Dietzel's factors.

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Poly-dimethylsiloxane (PDMS) 기판 위에 형성된 나노구조를 이용한 시각 인장센서의 개발 (Development of Optical Strain Sensor with Nanostructures on a Poly-dimethylsiloxane (PDMS) Substrate)

  • 김건휘;우현수;임근배;안태창
    • 센서학회지
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    • 제27권6호
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    • pp.392-396
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    • 2018
  • Structural color has many advantages over pigment based color. In recent years, researches are being conducted to apply these advantages to applications such as wearable devices. In this study, strain sensor, a kind of wearable device, was developed using structural color. The use of structural color has the advantage of not using energy and complex measuring equipment to measure strain rate. Wrinkle structure was fabricated on the surface of Poly-dimethylsiloxane (PDMS) and used it as a sensor which color changes according to the applied strain. In addition, a transmittance-changing sensor was developed and fabricated by synthesizing additional glass nanoparticles. Furthermore, a strain sensor was developed that is largely transparent at the target strain and opaque otherwise.

스마트윈도우 응용을 위한 FTO 기판 위에 증착된 VO2 박막의 광학적 특성 (Optical Properties of VO2 Thin Film Deposited on F:SnO2 Substrate for Smart Window Application)

  • 강소희;한승호;박승준;김형근;양우석
    • 한국재료학회지
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    • 제23권4호
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    • pp.215-218
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    • 2013
  • Vanadium dioxide ($VO_2$) is an attractive material for smart window applications where the transmittance of light can be automatically modulated from a transparent state to an opaque state at the critical temperature of ${\sim}68^{\circ}C$. Meanwhile, F : $SnO_2$ (F-doped $SnO_2$, FTO) glass is a transparent conductive oxide material that is widely used in solar-energy-related applications because of its excellent optical and electrical properties. Relatively high transmittance and low emissivity have been obtained for FTO-coated glasses. Tunable transmittance corresponding to ambient temperature and low emissivity can be expected from $VO_2$ films deposited onto FTO glasses. In this study, FTO glasses were applied for the deposition of $VO_2$ thin films by pulsed DC magnetron sputtering. $VO_2$ thin films were also deposited on a Pyrex substrate for comparison. To decrease the phase transition temperature of $VO_2$, tungsten-doped $VO_2$ films were also deposited onto FTO glasses. The visible transmittance of $VO_2$/FTO was higher than that of $VO_2$/pyrex due to the increased crystallinity of the $VO_2$ thin film deposited on FTO and decreased interface reflection. Although the solar transmittance modulation of $VO_2$/FTO was lower than that of $VO_2$/pyrex, room temperature solar transmittance of $VO_2$/FTO was lower than that of $VO_2$/pyrex, which is advantageous for reflecting solar heat energy in summer.

티타늄과 비귀금속 합금에 중간층으로 적용한 Au bonding agent의 금속-도재 결합에 대한 평가 (Evaluation of Bond Strength in cp-Ti and Non-precious Metal-Ceramic System Using a Gold Bonding Agent)

  • 이정환;안재석
    • 대한치과기공학회지
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    • 제31권4호
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    • pp.15-23
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    • 2009
  • The aim of this study was to evaluate the bond strength of using a Au bonding agent applied on cp-Ti and nonprecious metal-gold-ceramic system. Metallic frameworks(diameter: 5mm, height: 20mm)(N=56, n=7per group) cast in Ni-Cr alloy, Co-Cr alloy and cp-Ti were obtained using acrylic templates and airborne particle abraded with $110{\mu}m$ aluminum oxide. Au bonding agent was applied on wash opaque firing as intermediate layer. SEM and SEM/EDS line profile were performed on the cutting the cross-section of the metal substrate-porcelain with intermediate Au coating. Groups were tested using shear bond strength(SBS) testing at 0.5mm/min. The mean SBS values for the ceramic-Au layer-metal combination were significantly higher than those ceramic-metal combination. While ceramic-Au layer-cp-Ti combinations failed to increase bond strength instead of using a titanium bonding porcelain. The appication of using Au intermediate layer significantly improve the bond strength combination with metal-ceramic system.

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화염 열복사의 파장별 선택적 반사를 위한 도료 코팅에 대한 수치적 연구 (Numerical study of a coating with pigment to selectively reflect the thermal radiation from fire)

  • 변도영;백승욱
    • 대한기계학회논문집B
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    • 제22권3호
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    • pp.399-407
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    • 1998
  • The infrared reflection coatings with pigment can be used to protect the surfaces of combustible materials exposed to fire. To obtain high reflectivities in the infrared range (0.5-10.mu.m) important to fire, several dielectric pigments, such as titanium dioxide, iron oxide, and silicon, can be synthesized to polymer coatings. The theoretical analysis shows that the coating design with particles diameter in the 1.5 to 2.5.mu.m range and volume fraction in the 0.1 to 0.2 range is estimated to be optimal. In the analysis of the radiation, the dependent scattering, absorption by polymeric binder, and the internal interface reflection are considered. In addition, the temperature distribution in the semi-transparent coating layer and an opaque substrate (PMMA) is also presented.

에어로졸 데포지션 법을 이용하여 제조한 SiO2 후막의 구조 및 광학 특성 (Structural and Optical Properties of SiO2 Thick Films by Aerosol Deposition Process)

  • 장찬익;고중혁
    • 한국전기전자재료학회논문지
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    • 제26권1호
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    • pp.6-12
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    • 2013
  • Aerosol deposition(AD) coating that enable fabricate films at low temperature have begun to be widely researched for the integration of ceramics as well to realize high-speed deposition rates. For application of ceramic thick film by AD to display and electronic ceramic industry, fabrication of dense structure with a no cracking is required. In this study, to fabricate dense ceramic thick film, the effect of crystal phase of starting powder was investigated. For this study, amorphous and crystalline $SiO_2$ powders were used as starting powders. Two types of $SiO_2$ powders were deposited on glass substrate by AD. In the case of amorphous $SiO_2$ powder, the deposited films had extremely incompact and opaque layer, irrespective of particle size. In contrast to amorphous powder, in the case of crystalline powder, porous structure layer and dense microstructure with no cracking layer were fabricated depending on the particle size. The optimized starting powder size for dense coating layer was $1{\sim}2{\mu}m$. The transmittance of film reached a maximum of 76% at 800 nm.