To watch 4K movies on your 4K TV, you will need a 4K player. A regular Blu-ray player will not display 4K resolution, as it is only capable of playing 1080p content. While you can still play Ultra HD Blu-ray discs on a regular HDTV using a regular Blu-ray player, the player will downconvert the 3840 x 2160 resolution video on the disc to a 1080p format that your TV can display. This means that you won't be able to take full advantage of your 4K TV's capabilities.
4K Blu-ray players offer superior video and audio quality compared to regular Blu-ray players. The 4K Ultra HD video format has four times the resolution of regular 1080p Blu-ray, resulting in a sharper, more textured picture. Ultra HD Blu-ray discs can hold much more data than standard Blu-ray discs, allowing them to deliver full 4K resolution along with enhanced color and contrast. This means that if you have a 4K TV and you want to see its best picture, a 4K Blu-ray player is a worthwhile investment. Additionally, Blu-ray discs stream through your HDMI cable to your TV at a much faster rate than streaming services like Netflix, resulting in better picture quality.