A few years ago now the resurgence of a technology popularised in the 1950's/60's has become incredibly popular and that technology is 3D movies. Whilst during the first instance 3D images were achieved with red and cyan coloured glasses and weren't to everyone's liking, the new technology has become much more advanced and now allows full colour 3D images that are just as sharp and detailed as a high definition 2D image.
This technology is now being introduced in the home with 3D television sets able to bring images to life in the living room with the help of these new glasses, but many people will be wondering how they work. The first thing to know is that there are two different types of glasses available: Passive and active lenses.
Passive Polarized Glasses
The latest iteration of the old red and green 3D glasses now uses a light technique called Polarisation, two projectors are used to deliver two images on the screen but each one will only be seen by one of the eyes thanks to this polarisation trick, creating a 3D image and the user can even tilt their head and not have to worry about the effect being diminished.
This technology is still being worked on as the process works best on front projection screens such as a cinema screen but the glasses are much cheaper than active shutter glasses making it much more affordable to buy replacements or additional sets when hosting a party to watch 3D sports or movies.
Active Shutter Lenses
Active shutter lenses work in a similar way to the polarisation in passive glasses but this is controlled by the glasses having liquid crystal displays that alternately shutter over one eye at any point, when synced with the refresh rate of the television (the speed at which the image is updated when watching TV) the 3D effect is achieved.
The downside with active shutter glasses is that they are battery operated; meaning if your glasses are not fully charged then you may find you have to plug them in or replace batteries midway through the programme or movie you are watching. Whilst you can generally pause TV these days it can be a source of frustration, as well as having to replace or buy extra sets of the glasses. With the glasses being more complex they obviously carry a heavier price tag and people are more reluctant to buy additional sets.
3D glasses have come a long way from the days of green and red filters; the technology has matured to provide full colour images and fewer headaches too.