We are presently the only manufacturer producing slim BD drives, and we are ranked at the top of the industry, as of September 2006, in terms of both technology and market share. Here, I'll discuss our drive mechanism for recording and playing Blu-ray Discs.
Mitsuro Moriya
Councilor BD Drive Development Taskforce Corporate R&D Division |
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The disc drive, which reads and writes information, is equipped with a component called an optical pickup. The optical pickup emits a laser beam with an extremely small diameter and focuses it on the recording surface of the disc for reading and writing.
Panasonic has been a forerunner in developing both discs and drives since the beginning of the CD era. Although drives are sometimes sold as individual units, many are built into personal computers, recorders and other products. This is why slimness is one of the top design priorities in drive development. Especially in a notebook PC, the thinness and performance of the mounted drive are directly related to the sales points of the PC itself. For this reason, the demand continues to grow for thinner, lighter, higher-performance drives, reflecting both end user and PC maker expectations for drive evolution.
In response to this demand, Panasonic launched its optical disc drive operations in 1994, well ahead of others in the industry. We mounted a CD-ROM drive in a notebook PC for the first time in the world. Then we successfully reduced the drive height from the previous 17 mm to 12. 7 mm, and developed a slim CD-ROM drive in 1996 and a slim DVD-ROM drive in 1998. The size of these Panasonic drives (128 mm wide, 129 mm deep, and 12.7 mm high) has now become the de facto standard for notebook PC drives.
Panasonic has continued to lead the industry by releasing a steady stream of new drives that comply with evolving disc standards. In 2003, we developed a 9.5-mm-thick recordable DVD drive, which was previously considered to be impossible by many in the industry. While maintaining the industry lead, we went on to capture the highest market share worldwide for slim recordable DVD drives.
In February 2002, a new standard was announced for Blu-ray Discs that uses a blue-violet laser beam. We decided right from the start to launch the development of an ordinary half-height-size (146-mm-wide, 190-mm-deep, 41.3-mm-high) BD drive for desktop PC use, while simultaneously aiming to develop the industry's first slim BD drive. Although the Blu-ray Disc was a brand-new standard at the time, it was inevitable that notebook PC manufacturers would require BD drives to be the same standard size with a height of 12.7 mm and also be fully compatible with CDs and DVDs. Our pride in being the industry leader for so many years compelled us to take on this challenge.
We began by establishing the technology to record and play a dual-layer 50-GB Blu-ray Disc with a half-height-size drive before anyone else in the industry. We thought that we would be able to achieve a slim, 12.7-mm-high BD drive by combining this technology with downsizing and slimming technologies that we had cultivated while developing recordable DVD drives. Backed by these technologies, we focused companywide efforts on achieving this slim, 12.7-mm-high BD drive.
For this project to succeed, it was essential that we make the optical pickup smaller and slimmer, and that we confirm operation of the three wavelengths necessary to support CD, DVD, and Blu-ray Discs.
To achieve a recording density that is nearly five times that of a DVD disc, Blu-ray Disc technology uses a high-NA objective lens and a short-wavelength laser to produce a laser beam with about 1/5th the spot size of the DVD laser. This made it necessary to increase the precision of the optical pickup components and their assembly accuracy by three to five times the development targets for the DVD drives. We also had to develop a mechanism to generate laser beams with three different wavelengths -- infrared (780 nm) for CD, red (650 nm) for DVD, and blue-violet (405 nm) for BD.
In autumn 2005, we finally achieved the mechanism for the slim, 12.7-mm-high BD drive. This drive is now equipped in a large number of notebook PCs.
Here, I would like to briefly describe the optical pickup part of that drive.
Mechanism of the Optical Pickup Built into the Slim BD Drive
The same integrated element (the optical system that produces the laser beam) and objective lens are used for CD and DVD. This technology was achieved based on know-how that we accumulated while developing our slim CD/DVD combo drives. We also included another integrated element and objective lens for the Blu-ray Disc that were developed entirely by Panasonic. The addition of advanced optical technologies for dual-layer discs made it possible to record and play on either of the recording layers with high precision.
The two integrated elements that I've just described combine with our ultra-small spherical aberration corrector, which is vital for reading the dual-layer disc, and our thin actuator, which precisely controls the motion of the two objective lenses, to form a unique Panasonic "black box" technology.
The technologies we just looked at are all incorporated into the optical pickup used in the drive. In addition to this, drive system technologies that maximize the performance of the optical pickup are required to create a highly reliable drive unit. In April 2006, Panasonic started shipping slim BD drives capable of recording and playing a dual-layer BD-R/RE disc for the first time in the industry. As of September 2006, Panasonic is the only manufacturer producing slim BD drives, and ranks at the top in terms of both technology and market share. We are also continuing to make further technical advances in order to develop even thinner drive units.
By applying the know-how and technical expertise that we accumulated while developing our half-height drives for PCs and other slim drives, we developed and introduced the Blu-ray Disc™ Player in the fall of 2006.
Even though we were able to apply a number of already established technologies, it did not mean that simply mounting a BD drive would instantly result in a marketable product. There were a variety of challenges that had to be overcome in order to develop a drive that was suitable for recorder use. A recorder has to record real-time broadcasts directly onto an optical disc, in addition to recording previously stored data. With a PC, TV programs are first recorded onto the hard disk and then copied onto an optical disc in normal usage. With a recorder, however, TV programs running from two to four hours in length are recorded directly onto the optical disc. When a drive is continuously operated for such long periods of time, the temperature inside the drive rises and can cause instability in the recording signal. To solve this problem, Panasonic drives are equipped with a function that detects and corrects unstable recording signals.
We have also finely tuned our drives to achieve the necessary level of AV quality, by reducing optical pickup travel noise, providing smooth, quiet disc tray operation, and shortening the time it takes to start recording or playing after the disc is loaded.
I hope you enjoyed this introduction to the world of disc drives, a world that few people ever think about since they are generally hidden from view.
As optical disc technologies evolve from CDs and DVDs to the Blu-ray Disc, we are continuously improving our drive performance to meet new and advanced requirements. By choosing to take on these difficult technical challenges, Panasonic is able to maintain our industry lead and produce products that successfully meet our customers' demands. To bring the enjoyment offered by the Blu-ray Disc to even more people, we are now developing in-vehicle BD drives and BD video cameras, and working to reduce the cost of all drives. As the history of our DVD development suggests, we can expect that the demand for more recording layers, slimmer sizes, and higher performance will also emerge for the Blu-ray Disc in the future. With this in mind, we will stay keenly aware of our customers' demands, and will continue to forge ahead with the technical advances that allow us to meet them.
