Samsung has unveiled new Ultra HD OLED TVs at IFA 2013, but for now they are just prototypes. Both flat and curved UHD OLED TVs are exhibited.
Updated with photos and more information
Samsung unveils 4K OLED TVs
Samsung unveiled its first 55-inch OLED TV in January 2012, and in 2013 Samsung launched its curved 55-inch OLED TV in USA, Europa, and Asia. At IFA in Berlin, Samsung has unveiled its first OLED TVs with 4K resolution.

Samsung unveils its first UHD OLED TV
The new OLED TVs are exhibited in both flat and curved 55-inch variants with 3840x2160 pixel resolution, four times higher than Full HD.

Samsung unveils its first UHD OLED TV
The Ultra HD OLED TVs are still prototypes, and Samsung says that it "demonstrates our technology leadership". Panasonic and Sony unveiled 4K OLED TVs in January 2013.