• Korea-Australia Rheology Journal
• /
• v.19 no.3
• /
• pp.165-169
• /
• 2007

The light guide plate (LGP) of LCD-BLU (Liquid Crystal Display-Back Light Unit) is usually manufactured by forming numerous dots by etching process. However, the surface of those etched dots of LGP is very rough due to the characteristics of etching process, so that its light loss is relatively high due to the dispersion of light. Accordingly, there is a limit in raising the luminance of LCD-BLU. In order to overcome the limit of current etched-dot patterned LGP, micro-lens pattern was tested to investigate the possibility of replacing etched pattern in the present study. The micro-lens pattern fabricated by the modified LiGA with thermal reflow process was applied to the optical design of LGP. The attention was paid to the effects of different optical pattern type (i.e. etched dot, micro-lens). Finally, the micro-lens patterned LGP showed better optical qualities than the one made by the etched-dot patterned LGP in luminance.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2008.11a
• /
• pp.291-292
• /
• 2008

• Journal of the Institute of Convergence Signal Processing
• /
• v.7 no.4
• /
• pp.161-168
• /
• 2006

In this paper, we propose a method for the pattern inspection of LCD module using the color compensation and pattern matching. The pattern matching is generally used for the inspection method of LCD module at the industry. LCD module has many defections such as the brightness difference of the back light, the optic feature of liquid crystal, the difference of the light penetrated by driving LCD and the color difference by the lighting. The conventional method without the color compensation can not solve these defections and decreases the efficiency of inspecting LCD module. The method proposed to inspect defective badness through the pattern matching after it compensated color difference of the LCD occurred by the various causes. At first, it revises with setting by standard tone of color with the LCD pattern of the reference image. And It perform the preprocessing and pattern matching algorithm on the compensated image. In experiment, we confirmed that this algorithm is useful to detect some defections of LCD module. The proposed methods was easy to detect the faulty product.

• Proceedings of the Korean Society for Technology of Plasticity Conference
• /
• 2006.05a
• /
• pp.95-98
• /
• 2006

LCD-BLU (Back Light Unit) is one of kernel parts of LCD unit. The fabrication method of a 3-D micro mold patterned with micro-lenses for the LGP (Light Guiding Plate), one of the most important parts of LCD-BLU, was presented. Instead of dot pattern made by etching, 3-D optical pattern design with $50{\mu}m$ micro-lens was applied in the present study. The micro-lens pattern fabricated by modified LiGA with thermal reflow process was applied to the optical design of LGP. The positive micro-lens patterned injection mold with different aspect ratios (i.e. 0.3 and 0.4) was fabricated with modified LiGA with thermal reflow process. The brightness of LCD-BLU increased as aspect ratio of micro-lens increased.

• Proceedings of the Optical Society of Korea Conference
• /
• 2004.07a
• /
• pp.70-71
• /
• 2004

Back light unit(BLU) using a microlens fabricated by the modified LIGA process for the liquid crystal display(LCD) is proposed, and some experimental results are presented. To realize the back light unit using microlens pattern, LIGA and reflow process are used.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.4
• /
• pp.30-35
• /
• 2020

The light guide plate (LGP) provides a surface light source on the back of the liquid crystal display (LCD), which is not self-emitting; thus, it is an essential component of display units requiring sufficient brightness. To maximize the light-emitting effect of an LGP, enough incident light, from the light source, should enter into its side. However, the current trend in LCD panels is represented by larger and thinner screens and this smaller thickness prevents the accordingly thin LGPs from providing sufficient brightness. This paper proposes a process for manufacturing wedge-type LGPs, which might increase the amount of incident light and, consequently the surface light emission, for applications in large LCDs. The proposed method was validated by building a dedicated manufacturing machine and performing illuminance experiments on the fabricated LGP.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.33 no.8
• /
• pp.720-725
• /
• 2009

Among many kinds of parts for Liquid Crystal Display (LCD), a Back Light Unit (BLU) that changes the path of the light from light source to screen is the most important part to improve optical performances such as uniformity and average value of brightness. Up to recently, design process of BLU has been carried out by depending on the experience of design engineer. Using this approach, however, is proven that it is hard to effectively deal with difficulties in a process of the LCD development such as frequent design modifications, various design requirements, and short-term development. To cope with this situation, we applied a Process Integration and Design Optimization (PIDO) based design environment. PIDO is a software package to integrate multiple simulation processes and find a better solution using various design techniques. In this research, we found a design solution satisfying all design requirements by using the PIDO.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.06a
• /
• pp.540-543
• /
• 2007

In this paper, we propose a new approach to reduce the audible noise generated by TFT-LCD module in mobile applications. We also analyzed impact factors which effect on the audible noise. It is expected that this noise source comes from various impact factors such as vibration of flexible printed-circuit board (FPCB) and LCD panel, and static electricity charged in window and back-light unit. Windowless type and window type models are evaluated to analyze noise level due to the static electricity charged in window. To obtain reliable and reproducible data, we constructed controllable test jig and measurement set-up.

• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.193-195
• /
• 2004

This paper presents a novel data transmit method using display units of mobile devices. Mobile devices such as personal-digital-assistants (PDAs) and cellular phones have a display unit. The typical display unit is a liquid-crystal-display (LCD) with an back-light. Since the proposed data transmit method uses the LCD or back-light as a data transmitter, it is a kind of sightable light communication. Tn order to transmit the data, the display unit drived by an application program on the platform of mobile devices. In this paper, detailed data transmit scheme, specific data protocol are presented and discussed. Finally, with the experimental results, usefulness of the proposed data transmit method is verified.

• Proceedings of the Optical Society of Korea Conference
• /
• 2006.07a
• /
• pp.547-548
• /
• 2006