Samsung Display Co Ltd developed an LCD panel with a resolution of 2,250ppi for VR/AR applications.
Samsung Display exhibited the panel and announced its details at the Society for Information Display 2017 (SID 2017), an academic conference that took place from May 21 to 26, 2017, in Los Angeles, the US (thesis number: 5.5). It was developed because a resolution higher than 2,000ppi is required for VR/AR, which displays images magnified by lenses, the company said.
The screen size and pixel count of the LCD panel are 1.96 inches and 4K (3,840 x 2,160 pixels), respectively. Samsung Display used a glass substrate instead of a silicon (Si) wafer so that panels with a larger screen size can be developed in the future. Its back plane is low-temperature polycrystalline Si (LTPS) TFT. The pitches of the sub-pixel and pixel are 3.76μm and 11.28μm, respectively.
The challenges in realizing the ultra-high resolution were the reduction of pixel size and the interference among pixels. To solve such problems, Samsung Display developed and introduced three technologies. They are (1) a new pixel alignment called "stagger type," which places three (red, green and blue) sub-pixels in a triangle shape, (2) short-channel TFT, whose channel length was reduced by 25%, and (3) production process that forms contact holes and wiring with a scale of about 1μm and color filters with a scale of about 4μm.
Samsung Display is considering applying the ultra-high resolution LCD technology to light field displays and hologram displays that can show natural 3D images. For example, to realize such 3D viewing with a smartphone, its screen size needs to be 5 inches or larger. Because the new technology was developed on the premise that a glass substrate is used, it is more suited for increasing screen size than ultra-high resolution panels using Si wafers, the company said.