News and Reviews....
Three D - The Formats April 2010
3-D TV is all the BUZZ. Due to this new wave of viewing, I thought it might be a good time to go over the formats. I will be discussing three, but have heard of at least 7 different ways or techniques to accomplish the effect.
Low Tech: 3D via Anaglyph 3D: This is probably the 3D you have viewed in the past. The glasses have a Cyan filter lenses in the left eye and a Red filter lenses in the right. Viewed without the glasses the look is like double vision. I have heard that some folks are sensitive to that method which brings on headaches to the user. This method also distorts the color accuracy of the content. Glasses with Blue and Red lenses also come under this method of 3D delivery. The Anaglyph Method is considered the least accurate and technically advanced of all methods.
Mid Tech: 3D DLP for TV first introduced in 2007 as a rear screen single chip TV. Taking advantage of the inherent speed of the DLP device, the display transmits left and right imagery separately for the stereoscopic imaging with high quality 3D glasses. This method uses video processing behind the display to achieve the switch from left eye to right eye rather then putting all information on the display and letting the glasses do the qualifying of the image as in the High tech model. Consumer-level 3D DLP enlists a specific technology referred to checkerboard imaging, where like the checker board, the red boxes are displayed then the black in full 1080P without the need to increase the bandwidth of the system. The images are displayed 60 Hz (cycles) right eye then 60 Hz (cycles) left eye to give the equivalent of the 120Hz full signal. But, since every other pixel is dedicated to either the right or left eye, only half the native resolution of the set is seen when using the 3D mode.
High Tech: 3D Shuttered Glasses The addition of high speed LCD shutter glasses when used, allow the appropriate eye to view the information. Thus, with the glasses total left and right eye signal a full 1920 x 1080 resolution can be accomplished, assuming the display can reach that resolution. This method uses a Infrared Emitter that is pointed at the audience to control the glasses.
High Tech: Active 3D Projectors The latest 3-chip 3D projectors utilize a more advanced technology capable of supporting full Active 3D whereby a 120Hz signal is fed to the projector ( full 1920 x 1080 60Hz, left; full 1920 x 1080 60 Hz right) and the right eye and left eye are displayed sequentially. Once again, high speed LCD shutter glasses are used and synchronized with the projector via an IR emitter, blocking the appropriate eye when the other eye information is displayed. The signal requirement is that you either need a high speed dual link DVI cable to transmit 120 Hz full HD signals to the projector from the source or two standard DVI/HDMI cables, one for the right eye content and one for the left eye content. HDMI 1.4 cables address to reduce this to a single cable.
There are several DLP two piece consumer projection systems and flat-panel displays that advertise 3D capabilities, but they do so only at reduced resolutions. By reducing the resolution, the electronics and response times are greatly simplified. Most gaming flat panels are maximum 1680 x 1050, and many of the single chip 3D projectors present a maximum of 1024 x 768 resolution so if you are in the market for 3D, take time to evaluate all specification on the delivery process.
Some of the questions we have been hearing about 3D are:
1. Will the glasses for my TV work on others, say if I go over a friends home to view a 3D Event. Answer: Maybe, It is too early to tell. It all depends on whether a STANDARD can be set for all manufactures to follow.
2. Are there other products needed to view 3D TV. Answer: Depending on the format of the TV, you might need to purchase an IR emitter that faces the audience. The emitter will be used in a specific type of Shuttered Eyeglasses that use the IR beam to sync the glasses to the frames of the picture.
For other reading on the issue see:
Three D - Where and When Jan. 2010
