• Journal of Korean Ophthalmic Optics Society
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• v.19 no.2
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• pp.135-143
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• 2014

Purpose: To evaluate the blue-light blocking ratio and luminous transmittance of blue-light blocking lenses using the blue-light hazard function as specified in international standard. Methods: In order to calculate the blue-light blocking ratio and luminous transmittance for a total of 41 blue-light blocking lenses from 8 manufacturers, UV-Vis spectrophotometer was used for measuring the spectral transmittance of wavelengths from 380 to 780 nm. Blue-light blocking ratio was calculated using blue-light hazard function as specified in ANSI Z80.3:2010 and ISO 13666(or Korean Standard KS B ISO 13666:2004). Results: The range of the blue-light blocking ratio was from 9.3 to 96.8%, the range of the transmittance from 53.5 to 92.7%, and the range of the luminous transmittance from 58.0% to 98.1%. In general the blue-light blocking lens prepared by coating tended to have a higher luminous transmittance, while those prepared by tinting a higher blue-light blocking ratio. Conclusions: The behavior of the spectral distribution of lenses showed the possibility of the performance improvement in the blue-light blocking lenses. Manufactures need to acquire their own technology that can evaluate the performance of blue-light blocking lens based in international standard.

• Journal of the Korean Society for Nondestructive Testing
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• v.35 no.1
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• pp.1-11
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• 2015

In this study, an online seed potato sorting system using a visible and near infrared (40 1100 nm) transmittance spectral technique and statistical model was evaluated for the nondestructive determination of infected and sound seed potatoes. Seed potatoes that had been artificially infected with Pectobacterium atrosepticum, which is known to cause a soil borne disease infection, were prepared for the experiments. After acquiring transmittance spectra from sound and infected seed potatoes, a determination algorithm for detecting infected seed potatoes was developed using the partial least square discriminant analysis method. The coefficient of determination($R^2_p$) of the prediction model was 0.943, and the classification accuracy was above 99% (n = 80) for discriminating diseased seed potatoes from sound ones. This online sorting system has good potential for developing a technique to detect agricultural products that are infected and contaminated by pathogens.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.1
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• pp.35-40
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• 2001

A spectral measurement system for reflection and transmission properties by using an optical fiber and an ellipsoidal mirror was newly developed. The hemispherical reflectance and transmittance spectra of several heating resisting ceramics materials were measured from visible to middle infrared region. The directional characteristics of reflection and transmission were also investigated in consideration of the absorptance. The measured data were analyzed by using a four flux model of radiation transfer, The radiation properties could be estimated by the obtained scattering and absorption coefficient spectra.

• Korean Chemical Engineering Research
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• v.56 no.6
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• pp.792-797
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• 2018

We have explained the synthesis of novel phenanthrene and pyrene substituted phthalocyanines (PC-PHE and PC-PYR) and fully confirmed the structures by its spectral, photo physical and elemental analysis. For these phthalocyanines we checked the UV-Visible absorbance in PGMEA and chloroform and transmittance checked in PGMEA. The transmittance results suggested that these phthalocyanines are showing more than 90% transmittance at the 450-550 nm region. These synthesized molecules are nicely soluble in almost all industrial solvents. We checked the aggregation property of these phthalocyanines in PGMEA, and the results suggested no any aggregation for these molecules in PGMEA. The thermogravimetric analysis results concluded that PC-PHE and PC-PYR had high thermal stability. All studies explain that these new phthalocyanines are more suitable for LCD green color filter application.

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.723-728
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• 2011

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.232-237
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• 2009

This study was performed to investigate the effect of high performance greenhouse films on growth and fruit quality of tomato. For this purpose, polyolefin (PO), fluoric, antidrop, antifog and thermal films were compared to normal film, ethylene vinyl acetate (EVA). In spectral irradiance of the films, UV ($300{\sim}400nm$) transmittance was highest in fluoric film and lowest in PO film. PAR (photosynthetically active radiation, $400{\sim}700nm$) transmittance was higher in fluoric, thermal and PO film, and near infrared ray (NIR, $700{\sim}1,100nm$) transmittance was higher in high performance films, compared to the EVA film. Total light transmittance was higher in order of fluoric, antifog, anti drop, PO, thermal, and EVA film. Day air temperature in greenhouse was highest under fluoric film and lowest under EVA film due to the light transmittance, while night air temperature was highest under PO and anti drop film due to the thickness of film. Tomato fruits grown under the high performance films had 0.2 to $0.5^{\circ}Bx$ higher soluble solids and 15 to 30% higher lycopene content, compared to those grown under the EVA film. The results showed that tomato fruit quality such as soluble solids and lycopene content can be heightened in terms of much irradiation and better light quality of high performance films, compared to the nomal film, EVA film.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.1
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• pp.61-66
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• 2002

A method for designing antireflection (AR) and antistatic (AS) coating layer by the use of conducting polymer as an electrically conductive transparent layer is proposed. The conducting AR coating is composed of four-layer with alternating high and low refractive index layer: silicon dioxide (n=1.44) and titanium dioxide (n=2.02) prepared at low temperature by sol-gel method are used as the low and high refractive index layer, respectively. The poly(3,4-ethylenedioxythiophene) which has the surface resistivity of 10$^4$Ω/$\square$ is used as a conductive layer. Optical constant of each ARAS coating layers such as refractive index and optical thickness were measured by 7he spectroscopic ellipsometer and from the measured optical constants the spectral properties such as reflectance and transmittance were simulated in the risible region. The reflectance of ARAS films on glass substrate was below 1 %R and the transmittance was higher than 95 % in the visible wavelength (400-700 nm). The measured AR spectral properties was very similar to its simulated results.

• Journal of the Optical Society of Korea
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• v.4 no.2
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• pp.94-99
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• 2000

Optical monitoring using the chromatic aberration of focusing optics is applied to auto-focus control in laser welding. The spectral transmittance of thermal radiation from a weld pool through an aperture depends on the wavelength of the spectral band and on the distance of the weld pool from the focusing optics. Its dependence has been used to monitor the focus shift in laser welding by measuring the spectral band signals filtered by the aperture. The difference between pulsed and continuous laser welding is analyzed. Furthermore, the dependence of the focus shift monitoring on the weld pool size variation is optimized to monitor the focus shift independently from the laser power change at the weld pool. The performance of the auto-focus control with chromatic filtering is presented for pulsed laser welding.

• Current Photovoltaic Research
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• v.5 no.1
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• pp.1-8
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• 2017

Two different fluorine-doped tin oxide (FTO)-coated glass substrates were investigated to find better suitability for CdTe solar cells. Substrate A consisted of FTO (300 nm)/$SiO_2$ (24 nm)/intrinsic $SnO_2$ (30 nm)/borosilicate glass (2.2 mm), and substrate B consisted of FTO (700 nm)/intrinsic $SnO_2$ (30nm)/borosilicate glass (1.8 mm). The overall thickness of the FTO/glass substrates was about 2.5 mm. The total light transmittance of substrate B was much higher than that of substrate A throughout the whole spectral region, even though the thickness of the FTO in substrate B was twice larger than that of the FTO in the substrate A. The short-circuit current greatly increased in substrate B and the external quantum efficiency (EQE) increased over the whole wavelength range. This study shows that the diffuse optical transmittance played a key role in the large EQE value in the blue wavelength region, and the direct transmittance played a key role in the large EQE value in the red wavelength region. The higher transmittance is due to the rough surface generated by the thicker FTO on glass. The conversion efficiency of the CdTe solar cell increased from 12.4 to 15.1% in combination of rough FTO substrate and Cu solution back contact.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.2
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• pp.320-327
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• 2010

The IR signature data of a ship is mainly affected by location, meteorological conditions(atmosphere temperature, wind direction and velocity, humidity etc.), atmospheric transmittance, solar position and ship surface temperature etc. The IR signatures received by a remote sensor at a given temperature and wavelength region is consisted of the self-emitted component directly from the object surface, the reflected component of the solar irradiation at the object surface, and the scattered component by the atmosphere without ever reaching the object surface. Computer simulations for prediction of the IR signatures of ships are very useful to examine the effects of various sensor positions. In this paper, we have acquired the IR signature for different sensor positions by using computer program for prediction of the IR signatures. The numerical results show that the IR signature contrast as compared to the background sea considering the meteorological conditions, solar and sky irradiations.