Session Index

S7. Display and Solid State Lighting

Display and Solid State Lighting IV
Saturday, Dec. 2, 2023  13:00-15:00
Presider: Prof. Kun-Yu Lai (National Central University, Taiwan) Prof. Chia-Yen Huang (National Yang Ming Chiao Tung University, Taiwan)
Room: 92277 (2F)
13:00 - 13:30
Manuscript ID.  0652
Paper No.  2023-SAT-S0704-I001
Invited Speaker:
Dong-Sing Wuu
Recent progress on advanced brightness enhancement films for display applications
Dong-Sing Wuu, National Chi Nan University (Taiwan)

The brightness enhancement film (BEF) has been widely used for displays, which deflects light rays toward
the normal direction and produces ray concentration and brightness enhancement effects. The typical BEF
structure is a prism with a 90-degree apex angle. To improve the visualization of displays, BEF is usually
combined with a diffusion layer or embedded with diffusion particles to achieve diffusion and better
visualization, which require post-processing or additional diffusion materials. In this study, we will present a
novel multifunctional optical film with nanoscale porosity features (pBEF). Micron-scale patterns are
distributed on the surface of pBEF, providing diffusion and visual modification functions. Nanoscale pores are
distributed in the inner layer of pBEF, which increase the transmittance of pBEF, reduce light recycling and
suppress color shift. Finally, the pBEF is applied to a direct type mini LED backlight unit, the brightness is
enhanced by a factor of up to 7% compared to the BEF incorporating dispersed particles and the color shift
∆xy is reduced by 15 - 40‰ compared to the regular BEF.

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13:30 - 13:45
Manuscript ID.  0890
Paper No.  2023-SAT-S0704-O001
Zong-Han Yang Secondary Optical Design of High Efficiency LED Direct-lit Lighting Board
Zong-Han Yang, Bo-Xiang Peng, Chi-Shou Wu, Tsung-Hsun Yang, Yeh-Wei Yu, Ching-Cherng Sun, National Central University (Taiwan)

This paper utilizes dual-die-encapsulated white LED as the light sources and employs a secondary optical design lens for application in a direct-type backlight panel. The designed lens in this study can decrease the number of light sources used in the direct-type backlight module, achieving a sparse arrangement effect. Furthermore, this study addresses the issue of the yellow halo phenomenon observed in practical samples. We propose a simplified blue-yellow light model, which helps explain the occurrence of the yellow halo phenomenon in real samples.

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13:45 - 14:00
Manuscript ID.  0080
Paper No.  2023-SAT-S0704-O002
Fu-He Hsiao Investigations on the high performance of InGaN red micro-LEDs with single quantum well structure
Fu-He Hsiao, Hon Hai Research Institute (Taiwan), National Yang Ming Chiao Tung University (Taiwan); Tzu-Yi Lee, National Yang Ming Chiao Tung University (Taiwan); Wen-Chien Miao, Hon Hai Research Institute (Taiwan), National Yang Ming Chiao Tung University (Taiwan); Yi-Hua Pai, Chun-Liang Lin, Chi-Wai Chow, National Yang Ming Chiao Tung University (Taiwan); Kazuhiro Ohkawa, King Abdullah University of Science and Technology (Saudi Arabia); Yu-Heng Hong, Hon Hai Research Institute (Taiwan); Chiao-Yun Chang, National Ocean University (Taiwan); Hao-Chung Kuo, Hon Hai Research Institute (Taiwan), National Yang Ming Chiao Tung University (Taiwan)

We have demonstrated the potential of InGaN-based red micro-LEDs for visible light communication. Our findings indicate that the sample with a single quantum well (SQW) structure performs better than InGaN red micro-LED with a double quantum wells structure. Furthermore, the SQW device has a superior modulation bandwidth with a higher data transmission rate. These results demonstrate that InGaN-based red micro-LEDs hold great promise for realizing full-color micro-display and visible light communication applications.

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14:00 - 14:15
Manuscript ID.  0769
Paper No.  2023-SAT-S0704-O003
Nitzan Dar Optical Properties and Applications of Cyanine J-aggregates
Nitzan Dar, Rinat Ankri, Ariel University (Israel)

Cyanines are unique molecules whose absorption and emission can be shifted over a broad spectral range from the ultraviolet to the near infrared. They can readily transform into J-aggregates with narrow absorption and emission peaks accompanied by a red shift in their spectra. Due to their high absorption coefficient, they can be used as a layer in photovoltaics; moreover, their high absorption and emission properties and their advantage of increased tissue penetration depth can be used for bioimaging.

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14:15 - 14:30
Manuscript ID.  0853
Paper No.  2023-SAT-S0704-O004
Pravinraj Selvaraj Versatile Energy-Efficient Smart Windows based on Self-Assembled Multistable Dynamic Scattering Mode
Pravinraj Selvaraj, Wen-Fa Cheng, Hsiu-Ming Kuo, Cheng-Kai Liu, Chao-Hsuan Wu, Chung Kung Lai, Jyun-Cong Lai, Sharon-Tan Fang-Jie, Ko-Ting Cheng, National Central University (Taiwan)

Here, we present novel self-assembled ionic liquid crystals (ILCs) doped with a negative cholesteric liquid crystal (CLCs) to offer electrically switchable and sustaining stable scattering mode light modulators based on dynamic fingerprint chiral textures (DFCT). The DFCT device can rapidly switch between stable transparent and stable scattering states by external stimuli, maintaining multistable states for extended periods, even after removing external stimuli. Furthermore, the DFCT device has polarization-independent scattering, transparent mode LC light modulators, low operating voltage, high contrast, wide viewing angles, and multistable full-color see-through windows.

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14:30 - 14:45
Manuscript ID.  0874
Paper No.  2023-SAT-S0704-O005
Shao-An Chen Green Thermally Activated Delayed Fluorescence OLED Based on Acridine Derivative with Different Dopant Concentrations
Shao-An Chen, Fu-En Shi, Chia-Hsun Chen, Man-Kit Leung, National Taiwan University (Taiwan); Tien-Lung Chiu, Yuan Ze University (Taiwan); Jiun-Haw Lee, National Taiwan University (Taiwan)

In this research, a green thermally activated delayed fluorescence (TADF) emitter based on an acridine derivative was used in the emitting layer (EML) of an organic light-emitting diode (OLED) with a maximum external quantum efficiency (EQEmax) of 16.21% with CIE coordinates of (0.339, 0.584). From time-resolved electroluminescence (TrEL) measurements, a significant decrease in the delayed emission time was observed with increasing doping concentration.

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14:45 - 15:00
Manuscript ID.  0302
Paper No.  2023-SAT-S0704-O006
Mu-Ju Wu Investigated aging test of blue/red micro-LEDs with various sizes
Mu-Ju Wu, Yi-Chun Lai, Shao-Yu Chu, Hsin-Ying Lee, National Cheng Kung University (Taiwan); Ching-Ting Lee, National Cheng Kung University (Taiwan), Yuan Ze University (Taiwan); Kai-Ling Liang, Wei-Hung Kuo, Industrial Technology Research Institute (Taiwan)

In this work, the gallium nitride (GaN)-based blue micro-light-emitting diodes (micro-LEDs) with various luminous areas of 15×15 and 9×9 μm^2 were fabricated. The red quantum dots (QDs) with and without titanium dioxide (TiO2) passivation layers were used as the color conversion layers to produce the red micro-LEDs. The TiO2 passivation layer was used to avoid the red QDs degraded by external environmental influences. After the aging test, the properties of the resulting blue and red micro-LEDs with various luminous areas driven by a constant current density of 667 A/cm^2 for 500 hr were measured and investigated.

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