Why Are Black Bars Still Visible on HD or 4K Ultra HD TV?

There is a good reason you may see black bars on your TV screen

When viewing theatrical films on your HDTV or 4K Ultra HD TV you may still see black bars on the top and bottom of some images, even though your TV has a 16x9 aspect ratio.

This information applies to televisions from a variety of manufacturers including, but not limited to, those made by LG, Samsung, Panasonic, Sony, and Vizio.

Black bars on top and bottom of LCD, Black bars on the sides of LCD
Lifewire / Adrian Mangel

16x9 Aspect Ratio Defined

What the term 16x9 means is that the TV screen is 16 units wide horizontally, and 9 units high vertically. This ratio is also expressed as 1.78:1.

No matter what the diagonal screen size is in inches or centimeters, the ratio of horizontal width to vertical height (aspect ratio) is constant for HDTVs and 4K Ultra HD TVs. For useful online tools that can help you determine the horizontal screen width in relation to screen height on any 16x9 TV, based on its diagonal screen size, is provided by GlobalRPH and Display Wars.

Aspect Ratio and What You See on Your TV Screen

The reason that you see black bars on some movie content is that many films were, and are, made in wider aspect ratios than 16x9.

For example, since the DTV transition, original HDTV programming is made using the 16x9 (1.78) aspect ratio, which fits the screen dimensions of today's LCD (LED/LCD), Plasma, and OLED HDTVs and 4K Ultra HD TVs.

However, many theatrically-produced films made since the mid-1950's, feature either the 1.85, 2.35 or other aspect ratios, which are even wider than the 16x9 (1.78) aspect ratio used for HD/4K Ultra HDTVs. This means you view these films on an HDTV or 4K Ultra HD TV (if presented in their original theatrical aspect ratio), you will see black bars on the top and bottom of a TV screen that has a 16x9 aspect ratio.
Aspect Ratios can vary from movie-to-movie or program-to-program. If you are watching a DVD, Blu-ray, or Ultra HD Blu-ray Disc, the aspect ratio listed on the package labeling will determine how it looks on your TV (many DVD packages may also state "Enhanced for 16x9 TVs").

  • If an HDTV program is being broadcast, or a film is listed as 1.78:1, then it will fill the entire screen correctly.
  • If the aspect ratio of a film is listed as 1.85:1, then you will notice small black bars on the top and bottom of the screen.
  • If the aspect ratio of a film is listed as 2.35:1 or 2.40:1, which is common for big blockbuster and epic movies, you will see large black bars on the top and bottom of the image.

Images displayed with black bars on the top and bottom are often referred to as "letterboxed".

Example of Black Bars on Letterbox Image
 Richard Wong / Getty Images

On the other hand, if you have a Blu-ray Disc or DVD of an older classic movie and the aspect ratio is listed as 1.33:1 or "Academy Ratio", or you are watching a rerun of a TV program made before HDTV was common, then you will see black bars on the left and right side of the image on a 16x9 aspect ratio screen, instead of the top and bottom, which is commonly referred to as a "pillar box" image.

Pillarbox image example

This is the result of movies that were made before the common use of widescreen aspect ratios or TV shows that were made before HDTV was in use (those old analog TVs had an aspect ratio of 4x3, which is more "squarish" looking).

On HD and Ultra HD TVs, as well as most video projectors, you can stretch a 4x3 image to fill the space. However, doing so you will distort the proportions of that image. This results in objects appearing wider horizontally, which is especially noticeable on the sides of the image.

Black Bars vs Filling the Screen

When viewing TV shows and movies, the main thing to be concerned about is not whether the displayed image fills the screen, but that you are seeing everything in the image that was originally filmed.

This means that native HDTV programs will fill the screen, many movies will have bars displayed with black bars on the top and bottom of the screen, and most movies made before the mid-1950's and pre-HDTV shows will be displayed with black bars on the left and right side of the image.

Being able to view the entire image as originally filmed is certainly the more important issue, rather than be concerned about how thick the black bars are, especially if you are viewing the image on a projection screen, which is a very large image, to begin with.

The Bottom Line

The way to look at the "black bar issue" is that the TV screen is providing a surface upon which you view images. Depending on how the images are formatted, the entire image may or may not fill the entire screen surface. However, the screen surface on a 16x9 television is able to accommodate more variations in image aspect ratio realistically than older 4x3 analog televisions.