Lenovo ThinkVision E55 LFD. Display diagonal: 138.7 cm (54.6\""), Display resolution: 3840 x 2160 pixels, HD type: 4K Ultra HD, Display technology: IPS, Response time: 8 ms, Native aspect ratio: 16:9, Viewing angle, horizontal: 178\u00B0, Viewing angle, vertical: 178\u00B0. Built-in speaker(s). Built-in USB hub. VESA mounting. Product colour: Black\n\nDisplayDisplay diagonal54.6Display resolution3840 x 2160 pixelsNative aspect ratio16:9Display technologyIPSHD type4K Ultra HDPanel typeIPSLED backlightYesDisplay brightness (typical)400 cd/m\u00B2Display brightness400 cd/m\u00B2Response time8 msAnti-glare screenYesScreen shapeFlatAspect ratio16:9Contrast ratio (typical)5000:1Maximum refresh rate60 HzViewing angle, horizontal178\u00B0Viewing angle, vertical178\u00B0Display number of colours1.07 billion coloursPixel pitch0.315 x 0.315 mmPixel density80 ppiHigh Dynamic Range (HDR) supportedYesColour depth10 bitColour gamut72%sRGB coverage (typical)95%NTSC coverage (typical)72%DCI-P3 coverag)