| Title |
A Study on the Application of an ECD Device to Optical Shutter for DVD Player |
| Authors |
이윤관(Yoon Kwan Lee) ; 박경찬(Kyung Chan Park) ; 유은호(Eun Ho Yoo) ; 박만효(Man Hyo Park) ; 강춘식(Choon Sik Kang) |
| Abstract |
The organic type ECD device for optical shutter on DVD player was successfully fabricated & evaluated. This device employ : an evaporated a-WO₃ film as electrochromic layer ; a PVDF-EC-NMP-THF-LiClO₄ as electrolyte layer ; a NiO film as counter electrode ; and ITO layer as transparent electrode between soda-lime glass substrate. This ECD shutter exhibited an useful operating characteristic such as contrast ratio as high as 30 to 1 in the transmission mode with an He-Ne laser(632.8㎚), operating voltage of lower than 2.5V, and response time less than 0.5 sec at room temperature. Cycling test with coloring and bleaching on this device was carried out for more than several hundred times, along with analysis and evaluation of optical properties & microstructure of fabricated layers by means of spectro-photometer, TEM and XRD method, and the accumulation of Li in both a-WO₃nd ITO film after cycling test was investigated by AES & SIMS analysis. From this research, it is found that a number of factors including maintenance of uniformity in both film & electrolyte, prevention of Li ion accumulation in film, optimization of structure design and good sealing condition can contribute to attaining the improvement of properties & life extension in ECD shutter for DVD player. |