Panasonic Introduces 3D TV
Panasonic Corp announced a PDP (Plasma Display Panel) TV that can display three-dimensional (3D) images Feb 9, 2010. The PDP TV, "3D Viera VT2," will hit the Japanese market April 23, 2010, along with a Blu-ray Disc (BD) recorder and a BD player that support 3D video.
"We will change the way people enjoy watching TVs," Panasonic said. "We would like to provide living rooms with a sensation of being dragged into a screen."
The 3D Viera VT2 comes in two screen sizes, 54 and 50 inches, and their expected street prices are ¥530,000 (US$5,900) and ¥430,000 (US$4,800), respectively. The BD recorder will be available in three models whose HDDs (hard disk drive) have capacities of 2 Tbytes, 1 Tbyte and 750 Gbytes, respectively. Their expected street prices are ¥300,000 (US$3,300), ¥200,000 (US$2,200)and ¥160,000 (US$1,800). The price of the BD player is expected to be about ¥130,000 (US$1,500).
"The price premiums for the 3D TV and the 3D BD recorder are ¥70,000 (US$780) and ¥20,000 (US$220), respectively," Panasonic said. "We would like to expand the 3D world with affordable prices."
Crosstalk Reduced by Improving Luminous Efficiency of PDP
Panasonic employed a "time-sharing method" that combines a PDP with a drive frequency of 120Hz, a BD player and active liquid crystal shutter glasses. In this method, images for the right and left eyes are alternately displayed by each frame, and the liquid crystal shutters open and close in synchronism with those images so that the right and left eyes receive different images.
The time-sharing method enables to view 3D images with a resolution of 1,920 x 1,080 pixels (full HD). Since CEATEC JAPAN 2008, a trade show that took place in 2008 in Japan, Panasonic has demonstrated 3D TVs using this method at all of the exhibitions it participated in.
The 3D TV will come with a pair of the special glasses, which can also be purchased separately for an expected street price of ¥10,000 (US$110). As for the contents for the 3D TV, firms such as film companies plan to release Blu-ray discs. And trial software will be included in a limited number of the new BD recorders and players for a sales campaign.
3D TVs using a time-sharing method have the following problem. When images for the right and left eyes overlap, crosstalk occurs. This time, Panasonic improved this problem by making changes to the PDP, liquid crystal shutters and BD player.
The new PDP, which was announced at the 2010 International CES, has a luminous efficiency four times higher than that of Panasonic's TVs released in 2007. The company increased the amount of ultraviolet rays generated by electric discharge, improved the light conversion efficiency when a fluorescent material is irradiated with ultraviolet rays and emits light, and enhanced the light extraction efficiency of the emitted light.
Because of the improved luminous efficiency, the fluorescent material keeps glowing for about 66% shorter time than that of the company's existing TVs. Also, it became possible to emit light in the order of "brightness to darkness" instead of "darkness to brightness," which is used for the previous models. As a result of the shortened afterglow time of the fluorescent material, the overlap of the images for the right and left eyes was reduced.
In regard to the active liquid crystal shutter glasses, the crosstalk was reduced by enhancing the accuracy of the liquid crystal shutters so that they open and close at a more precise timing.
MPEG-4 MVC Employed
The new BD recorder and player support the MPEG-4 MVC (Multi-view Video Coding) standard to play 3D video stored on a Blu-ray disc. Panasonic proposed that Blu-ray Disc Association (BDA) should employ the standard, said Takuya Sugita, Panasonic's video business unit director.
The MPEG-4 MVC data of the encoded full-HD images for the left eye is recorded as "standard images." As for the images for the right eye, the part that overlaps the standard images is not recorded (only the part that is different from the standard images are encoded).
With this method, full-HD images can be encoded 1.3 times more efficiently than in the case where full-HD images for the right and left eyes are respectively encoded, Panasonic said. To improve the accuracy in decoding the images for the right eye, not only the corresponding images for the left eye but also the preceding and following frames of the frame being decoded are referred to, Sugita said.
By Shinya Saeki, Nikkei Electronics
