How 3D glasses work

3D can be an exciting immersive experience.  We thought we’d break down the two 3D glasses technologies available and give you a run-down on what each technology is called and what they do to produce a 3D image.

3D glasses work by displaying a different image to each eye. Our brain then merges each image into one, but with 3D characteristics. This, in turn, “dupes” our brains into thinking that it is seeing an image in 3D, so it creates an image with depth for you.

 

Types of 3D Glasses

There are two types of 3D glasses – Passive Polarized & Active Shutter. Both achieve their 3D visuals in a different way.

Passive Polarized glasses look a lot like sunglasses, not unlike what you get when you visit the movies. The TV or projector has a special filter that polarizes each line of pixels. This filter makes the odd lines on the screen only visible to the left eye, and the even lines only visible to the right. Your brain then interprets the image as a 3D image. Without the glasses, the image looks normal. A downside to this system is that the image is not Full HD 1080p as it halves the amount of pixels visible.

Active Shutter glasses use batteries and a transmitter that syncs with the rapidly moving shutters for each eye with the on-screen display.

The 3D image resolution is the same as the 2D image displayed on the same screen. This is because the left and right eye images are shown in sequence rather than at the same time. The 3D glasses sync with the projector's refresh rate to sequence the images that produce a 3D image to the viewer.

 

Optoma 3D Glasses

All of the projectors we produce at Optoma are active 3D. They can however be converted to passive 3D if required with the use of a silver screen and a passive 3D filter.

At Optoma, we recommend two different types of Active 3D glasses:

ZD302 – These glassed incorporate DLP Link™ technology which use line of sight to the screen to produce a 3D image. If you look away and then back to the screen, the glasses will display a very slight stutter as they re-sync with the projector.

ZF2300 – These 3D glasses use RF (Radio Frequency) technology to sync with the projector. RF synchronisation eliminates any potential sync issues and many glasses can be paired to the same projector. As these glasses need an RF emitter to function you will need a “ZF2300 starter kit” that includes an emitter and a pair of glasses.

 

 

Full 3D vs 3D ready

If your projector is Full 3D it can play 3D content from a DVD player or games console - you just need the glasses.  If the projector is '3D ready' - it is still possible to watch content on 3D but you would need additional equipment including a PC with quad buffered graphics card and professional 3D software through which you would play the content.  This is not recommended for general home use.