Active shutter 3D system
The timing synchronization to the video equipment may be achieved via a wired signal, or wirelessly by either an infrared or radio frequency (e.g. Bluetooth, DLP link) transmitter.
This is done by turning off the backlight between refreshes, while waiting for the shutter glasses to switch eyes, and also for the LCD panel to finish pixel transitions.
[10] It aimed to increase acceptance of 3D products by consumers by extending the agreement to various manufacturers of 3D TV, computers, notebooks, home projectors, and cinema hardware.
The press release in the announcement said, "Universal glasses with the new IR/RF protocols will be made available in 2012, and are targeted to be backward compatible with 2011 3D active TVs.
"[12] Field Sequential has been used in video games, VHS and VHD movies and is often referred to as HQFS for DVDs, these systems use wired or wireless LCS glasses.
In 1982, Sega's arcade video game SubRoc-3D came with a special 3D eyepiece,[16] which was a viewer with spinning discs to alternate left and right images to the player's eye from a single monitor.
In 1999–2000, a number of companies created stereoscopic LC shutter glasses kits for the Windows PCs which worked with application and games written for Direct3D and OpenGL 3D graphics APIs.
These kits only worked with CRT computer displays and employed either VGA pass-through, VESA Stereo or proprietary interface for left–right synchronization.
The most prominent example was the ELSA Revelator glasses, which worked exclusively in Nvidia cards through a proprietary interface based on VESA Stereo.
The glasses kits came with driver software which intercepted API calls and effectively rendering the two views in sequence; this technique required twice the performance from the graphic card, so a high-end device was needed.
Visual glitches were common, as many 3D game engines relied on 2D effects which were rendered at the incorrect depth, causing disorientation for the viewer.
SplitFish EyeFX 3D was a stereo 3D shutter glasses kit for the Sony PlayStation 2 released in 2005; it only supported standard-definition CRT TVs.
[19] The kit arrived too late in the product cycle of the console when it was effectively replaced by the PlayStation 3, and only a few games were supported, so it was largely ignored by gamers.
[21] With the release of this technology to the home-viewer market as of 2009, many other manufacturers are now developing their own LC shutter glasses, such as Unipolar International Limited, Accupix Co., Ltd, Panasonic, Samsung, and Sony.
These solutions utilize the inherent speed advantage of the Digital Micro-mirror Device (DMD) to sequentially generate a high refresh rate for the left and right views required for stereoscopic imaging.
It effectively compacts two L/R views into a single frame by using a checkerboard pattern, only requiring a standard 1080p60 resolution for stereoscopic transmission to the TV.
DLP Link keeps sync by embedding briefly-flashed white frames during the display's blanking interval, which are picked up by the LC shutter glasses.
[26] Plasma display panels are inherently high-speed devices as well, since they use pulse-width modulation to maintain the brightness of individual pixels, making them compatible with sequential method involving shutter glasses.
Modern panels feature pixel driving frequency of up to 600 Hz and allow 10-bit to 12-bit color precision with 1024 to 4096 gradations of brightness for each subpixel.
The sets utilize the same checkerboard pattern compression scheme as their DLP TVs, though only at the native resolution of 1360×768 pixels and not at HDTV standard 720p, making them only usable with a PC.
In this scenario, the amblyopic patient wears electronically programmable liquid crystal glasses or goggles continuously for several hours during regular everyday activities.
