• Korean Journal of Optics and Photonics
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• v.12 no.5
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• pp.425-428
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• 2001

In this work, we propose a new optical configuration for a 3-stack color LCD using subtract color mixing method. This configuration consists of 3 color polarizers, a neutral polarizer and 3 LC cells. With the proposed configuration, we can increase the contrast ratio practically by using a neutral polarizer and reduce the manufacturing cost. To reduce wavelength dispersion, the sequence of polarizers is optimized.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.6
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• pp.24-31
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• 2010

Laser carbonization of a polymer layer can be employed in various applications in the microelectronics industry, e.g repairing brightness pixels of an LCD panel. In this work, the process of thermal degradation of LCD color filter polymer by various laser sources with pulsewidths from CW to fs is studied. LCD pixels are irradiated by the lasers and the threshold irradiance of LCD color filter polymer carbonization is experimentally measured. In the numerical analysis, the transient temperature distribution is calculated and the number density of carbonization in the polymer layer is also estimated. It is shown that all the lasers can carbonize the polymer layers if the output power is adjusted to meet the thermal conditions for polymerization and that pulsed lasers can result in more uniform distribution of temperature and carbonization than the CW laser.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.24 no.2
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• pp.155-159
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• 2015

Light emitting devices (LEDs) are widely used in the liquid crystal display (LCD) industry, especially for LCD back light units. Therefore, much research has been performed to minimize manufacturing costs. However, the current process does not process LED chips from broken substrates even though the substrate is expensive sapphire wafer. This is because the broken substrates lose their alignment marks. After pre-processing, LED dies are glued onto blue tape to continue post-processing. If auxiliary alignment marks are stamped on the blue tape, post-processing can be performed using some of the LED dies from broken substrates. In this paper, a novel stamper module that can stamp the alignment mark on the blue tape is proposed, designed, and fabricated. In testing, the stamper was reliable even after a few hundred stamps. The module can position the stamp and apply the pattern effectively. By using this module, the LED industry can reduce manufacturing costs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.51-52
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• 2006

FFL의 내구성 및 신뢰성 확보를 위해 Lamp 상태에서 원하는 부위에 $-15^{\circ}C$를 유지하기 위한 Cold Spot을 부착하여 Lamp안의 Hg이 완전히 포집되도록 한다. 이후 이 Cold Spot을 제거하여 Hg peak과 Ne Peak의 Ratio의 변화를 관찰하며 Hg이 이동하는 것을 관잘 하여 Lamp 내에서 이동 속도와 Lamp 간에 이동 속도를 확인 할 수 있다. Lamp 내에서는 80분이 경과한 후에 Hg 이동이 Saturation되는 것을 확인 할 수 있고, Lamp 간에는 100시간이 경과후에 Saturation 되는 것을 확인 할 수 있었고, Ratio는 Channel내는 70 ~ 150, Channel간에는 6~10 정도임을 확인하여 Hg이 이동되는 속도와 회복되는 수준을 알 수 있었다.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1370-1375
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• 2004

This article investigates the heat transfer characteristics in a RTA system for LCD manufacturing and suggests a way to evaluate the quality of a poly-Si film from the thin film optics analysis. The transient and one-dimensional conductive/radiative heat transfer equation considering wave interference effect is solved to predict surface temperatures of thin films. In dealing with radiative heat transfer, a one-dimensional two-flux method is used and the ray tracing method is also utilized to account for the wave interference effects. It is assumed that each interface is assumed diffusive but the spectral radiative properties are included. It is found that the selective heating region exists for various wavelengths and consequently may contribute to heat the poly-Si film. Using the formalism of the characteristic transmission matrix, the lumped structure reflectance, transmittance, and absorptance are calculated and they are compared with experimental data of the poly-Si film during the SPC process via the FE-RTA (Field-Enhanced RTA) technology.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.7
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• pp.1725-1728
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• 2009

This research developed process control device and FGV pattern generating device essential for full gate visual inspection to improve process so that defect detection capability may be maximized in specified environment. The devices developed in this research, which can be swiftly replaced in case loss or error occurs, are anticipated to improve module yield as well as maintain tact loss near '0'. In addition, as a result of mounting H/W and S/W system to control detailed operation sequence in production line and executing performance check and verification, detection rates were 98.1% and 99.1% respectively for pixel defect by tact and line defect, and yield of the entire module process including gate and visual level test increased up to 98.3%.

• Journal of Technologic Dentistry
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• v.45 no.3
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• pp.74-80
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• 2023

Purpose: This study aimed to evaluate the fit of the anterior and posterior teeth printed using two light-curing three-dimensional (3D) printers. Methods: Anterior and posterior single crowns were designed using dental software and were printed using 2 types of 3D printers, liquid crystal display (LCD) and digital light processing (DLP) (n=40). After the printed crown was scanned again from inside and outside, the prepared teeth were evaluated using a 3D program. To compare the root mean square (RMS) results among groups (α=0.05), the one-way analysis of variance and Tukey's test were used. Results: No statistically significant difference was found between the mean RMS values of the anterior and posterior teeth (p>0.05). However, as a result of comparing the internal, external, and tooth shapes, the DLP group showed significantly low errors in the inner and outer surfaces than LCD group (p<0.05). Conclusion: In terms of clinical acceptance standard of 100 ㎛, the fit of the anterior and posterior teeth fabricated using LCD and DLP was clinically acceptable.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.159-160
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• 2000

A new manufacturing method using laser transfer technology was developed for a color filter of TFT-LCD. This method can make red, green and blue color layer at the same time without several baking processes. Simple process, no residue, good edge profile, and so on are merits of this process. The same performances (such as color characteristics, reliability, hardness and so on) of current color filter were achieved with this process.

• IE interfaces
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• v.17 no.spc
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• pp.131-140
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• 2004

The purpose of this paper is to develop and show the efficiency of the URL(Unload Request Logic) and LRL(Load Request Logic) of the dispatcher in the Fab(Fabrication) Manufacturing Execution System. These logics are the core procedures which control the material(wafer and glass substrate) flow efficiently in the semiconductor and LCD fab considering inter-bay as well as intra-bay material flow. We use the present and future status information of the system by look-ahead and the information about the future transportation schedule of Automated Guided Vehicles. The simulation results show that the URL and LRL presented in this paper reduce the average lead time, average and maximum WIP level, and the average available AGV waiting time.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1497-1500
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• 2006

Inkjet printing technology can reduce the LCD color filter manufacturing cost more than 50 %. Uniform color filter patterning can be achieved only with proper ink and barrier materials. We developed new ink and black matrix materials for inkjet color filter. The ink materials have low volatility while they have very high solid content. The black matrix materials have very precisely controlled surface energy so that the inks can fill the pixels evenly and completely. We controlled the ink drop volume and ink material to minimize the thickness difference between the black matrix and the color pixel. Micron-order jetting position accuracy was achieved. We successfully printed 14.1" color filters using our ink and black matrix materials.