3D technology: what, why and how
3D cinematography has been around for quite a while, but there was never much buzz about it. This was mostly because wearing the cheap-looking red-and-blue cardboard glasses not only seemed geeky, but also gave you headaches. Moreover, the 3D wasn’t as spectacular when compared to the ticket price, and adding seat-vibrations and other real-life effects was mostly regarded as a weak gimmick not adding much to the experience.
These days however, 3D technology is packing a serious punch. What with James Cameron, the one director responsible for both Aliens and Terminator original films deciding to produce Avatar in full 3D, the craze about 3D has started and it’s making it’s way into our theatres, TV sets and laptops.
3D technology today revolves around the special glasses. Out with the funny-looking do-it-yourself style glasses, and in with the cool shades. In essense, the glasses all do the same thing: allowing selective images to pass through, so your eyes only see part of what’s happening on-screen. This way, your brain is tricked into percieving depth on a 2-D screen. There are several 3D technologies that can be employed for a 3D image:
Types of 3D technologies
• Anaglyph imagery in which two images, one with red and one with blue hues, of the same object, are superimposed on the same screen. To view the image correctly, one has to use different filters for each eye, hence the blue and red glasses;
• Polarization systems use glasses with special polarized filters to sort out what kind of light passes to through. The image is projected using two different projectors aiming at the same screen, each with a different polarized filter. The screen has to be silver in order for the system to work;
• LCD shutter glasses simply dim one lens at a time, depending on what happens on the screen. They do it really fast so your eyes don’t percieve the phenomenon, and they are synchronized with the TV, which is why they have to be plugged in ore connected somehow in order to work;
• Inference filter technology uses different wavelenghts for red, blue and green and a pair of glasses then allows one type of wavelength for one eye, and another for the other.
With time, of the four basic 3D technologies, a couple have gained momentum, making them 3D standards we see in coolest gadgets today: the polarization system, and the LCD shutter glasses.
The polarization system is cheap to mass-produce, so it’s mostly used in cinemas: the glasses are fairly cheap and the expensive equipment – the silver screen and the projectors – are under direct supervision of the cinema employees. The LCD glasses, however, are better suited for TV sets at home – since the HDTV is less expensive than having two projectors around the house.