Active 3D Stereoscopic Technology
Active 3D Stereoscopy
The active 3D technology is used inside 3D monitors, TV as well as projectors and cinema systems. The common elements of this technology are active electronic glasses taking care about shuttering between left and right eye. The glasses needs a power supply and contain an active electronic – this is the origin of the active 3D technology term.
Active 3D projection
The principle will be shown on a 3D projection example. For active 3D projection a single one projector working in a double frame rate mode is sufficient. Such projector can be e.g. DepthQ projector (one of the first price acceptable 3D projector with a long tradition of development and fine tuned 3D functions). One special signal source (generated by DepthQ Media Player software in this case) contains both left and right eye image. The data flow is doubles and it contains a sequential series of left and right eye images. The projector projects the images sequentially on the screen as well.
Active 3D glasses
3D active glasses take care about the view separation. The glasses are synchronized remotely with the PC by IrDA signal. The LC panels in the glasses sequentially change the transmittance for the left and right eye view so the non-proper eye view is always blocked.
Aktivní 3D monitory a 3D televizory
3D TV and monitors works on the same principle as 3D active projectors. The visualization unit can be base don CRT, plasma or LCD principle. The active 3D glasses alternating between L and R view synchronized with the unit by IR signal are used again.
Advantages of active 3D technology
The main advantage of active 3D projection is a simple setup, standard screen and only one projection device required. Single projector solution makes possible 2D and 3D fast switching. A significant disadvantage is fragile glasses requiring service and batteries. The glasses service request makes the use of this technology e.g. in digital cinemas problematic. On the other hand this technology is optimal for small installations targeted on home 3D cinemas and PC games applications.
Overview of 3D stereoscopic technologies:
| technology | color informations | rozlišení obrazu | projection | monitors / tv | num. of viewers | 3D cinema expenses [price / operating costs] |
| Active 3D | full | high | yes (2) | yes (3) | limited (4) | high / high |
| Passive 3D | full | high | yes | yes | high | high / low (5) |
| 3D Polarization Modulator | full | high | yes | no | high | middle / low |
| 3D Auto-Stereoscopic Monitors | full (1) | low | no | yes | low | - |
| 3D Anaglyph | very bad | middle | yes | yes | high | low / low |
(2) - active 3D is not suitable for large 3D cinemas. Active 3D glasses are expensive and servising is also hard job (repairing, changing/recharging bateries).
(3) - active 3D displays (3D TV, computer 3D flat panels) provide the highest 3D quality from all 3D screens.
(4) - number of viewers is limited by expensive 3D glasses and the wireless signal range.
(5) - 3D Modulator is currently the best 3D technology for all modern 3D digital cinemas.