In this study, a 5.9-inch foldable Book-Type AMOLED display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm.

-In this study, a 5.9-inch foldable active-matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10 À6 g/m 2 Áday or less, which improves OLED reliability.With these techniques, we have developed a book-type display, which is repeatedly foldable like a book, and a tri-fold display including a display area, which is foldable in three.