3D Basics

• Your television shows images on a two-dimensional plane. To create 3D images, you need to wear glasses that allow your eyes to see different images at different times. When wearing the glasses, your brain perceives the succession of images as depth, making the images on the screen appear to pop out. Smaller screens, such as those on a 3D-enabled cellphone, allow you to see 3D images without the glasses. However, you must wear glasses to view images on a larger screen, such as a TV. Without the glasses, the images on the TV appear slightly distorted or in only two dimensions.
  
  

Active 3D

• Active-shutter 3D glasses have small LED screens in each lens. When you watch a 3D movie or television show, the TV sends an infrared signal to the active-shutter glasses, telling each lens when to dim the image in that eye. The lenses dim in rapid succession, meaning you only see images in one lens at a time, which tricks your brain into perceiving depth on the screen. The glasses require a battery to work, similar to a small watch battery, and weigh more than passive 3D glasses. As a result, some active 3D glasses weigh more -- up to an ounce or two -- whereas passive glasses weigh about half an ounce.
  
  

Passive 3D

• Passive 3D TV uses 3D glasses similar to the ones used at movie theaters. These lightweight classes have a filter over each lens that blocks out different levels of light from each eye. As a result, each eye perceives the same image differently. With both eyes seeing different colors when viewing the same image, the glasses trick your brain into perceiving what you see as depth on the screen. However, the lack of technology in the glasses leads to some loss of image quality. Images appear blurry when you first start viewing 3D, and do not reach the same depth as active-shutter glasses.
  
  

Considerations

• Cost plays a factor in the different types of 3D TVs. While both types of TV sets have similar manufacturing costs, the 3D glasses do not. Active-shutter glasses use more advanced technology than passive glasses, and produce a better 3D image with more depth. Active-shutter glasses also cost more than passive glasses. While you can purchase passive glasses fairly cheaply, active glasses can cost over a hundred dollars each at the time of this publication. Both types of glasses are fragile and will break if dropped or stepped on. However, active-shutter glasses generally have a higher build quality and last longer if used correctly.