3D viewing options that are available and used at home or in the cinema require the use of 3D glasses. However, technologies in various stages of development make it possible to view a 3D image on a TV or other video display device without glasses.

The biggest problem with viewing 3D images on a television (or video projection screen) is that humans have two eyes, which are a few inches apart.

We see 3D in the real world because each eye sees a slightly different image of what is in front of it and transmits that image to the brain. The brain combines the two images, resulting in the correct viewing of a natural 3D image.

Because traditional video images displayed on a TV or projection screen are flat (2D), both eyes see the same single image. Still and moving image photography tricks can provide a sense of depth and perspective in the displayed image. However, there are not enough spatial cues for the brain to accurately process what is being viewed as a natural 3D image.