The 10 Best USB DVD Drives
The Rise And Fall Of The Built-In Optical Drive
DVDs, like CDs, require a laser-powered mechanism in order to read or write to them. An optical drive pairs that system with a mechanism for spinning the disc in question, so that all areas of the disc are accessible to the lens. They were fist made commercially available by Sony in 1987.
For the first few years, the technology was used primarily for music CDs and software CD-ROMs. As this was the primary means of installing new software on a computer, most PCs included an optical drive in their design. This gave users the freedom to use new programs, listen to music straight from their computers, and, in many cases, get access to the internet.
The introduction of the DVD in 1997 added even more uses for optical drives. Because of their high data storage capacity, they were the perfect vehicle for consuming video content like movies and TV shows. For the first several years of their use, internet connections fast enough to download large video files in a reasonable timeframe were hard to come by. This helped sustain the need for optical drives, updated for the new disc format, in computers during this period. While downloading music and software from the internet was becoming much more of a possibility for many consumers, it would still be a few more years before the same would be true of video content.
By the early 2010s, it became more and more common for computer manufacturers to eschew optical drives from their machines altogether. This was due primarily to the amount of physical space they demand. As laptops and even desktop computers began confining themselves to slimmer and lighter profiles, there simply wasn't room for the mechanics of a disc drive. At the same time, it became increasingly possible to download and stream movies and other video content over the average home internet connection.
Of course, many people still need a way to read CDs, DVDs, and Blu-ray discs. Whether you've amassed a collection of your own or want to watch something that's not available for streaming, the only option may be to buy an external drive. Thankfully, there are several reliable models on the market, and most of them feature simple plug-and-play functionality.
A Brief History Of The DVD
DVDs were introduced to the market in 1997 by Sony, Panasonic, and Toshiba. They added much needed storage space to the disc format, with a capacity of 4.7 Gigabytes. With about seven times the amount of data storage of a CD-ROM, the digital versatile disc lent itself especially well to video.
While it was possible to write video content onto earlier optical disc formats, full-length movies typically occupy several gigabytes of space, and the DVD was the first to be able to comfortably accommodate them. This led directly to the rise of the format's popularity as it eclipsed the VHS tape for video rentals and purchases. The discs offered several other advantages over their predecessors, including the ability to skip between scenes at the press of a button, and, of course, eliminating the need for rewinding between viewings.
The popularity of the format gave rise to several new industries. The first was the mail-order video rental service, the most popular of which was Netflix. Because of the lightweight and highly portable nature of DVDs, especially when compared to the VHS, it allowed for a reinvention of how home-entertainment could be distributed. While this had severely negative consequences for brick-and-mortar video rental stores like Blockbuster, which filed for bankruptcy in 2010, the DVD-by-mail industry would itself grow into a multi-billion dollar business before being supplanted by video streaming.
The second industry that grew from the rise of the DVD was video extras. It was the first format that allowed movie studios and distributors to provide an interactive experience for viewers at home. Customized title menus, bonus footage, and behind-the-scenes features and interviews were among the innovations in this area. While the content would ultimately migrate, along with the movies themselves, to online streaming platforms, these exclusive additions proved to help the industry market and sell more copies of new movies as well as re-release films previously available without them.
In addition to streaming, the introduction of the** Blu-ray format** by Sony in 2006 also had an impact on the DVD's downfall. A standard double-layered Blu-ray Disc has a capacity of 50 Gigabytes, over 10 times that of a DVD, and occupies the same physical footprint. This allows for a higher-resolution home viewing experience, which grew to be especially valuable as high definition, 4K, and 3D televisions became increasingly available and affordable throughout the 2010s.
How A DVD Drive Works
A DVD drive consists of impressively few components. The most important one is the laser sled, which houses the lens used to read information off an inserted disc. It is positioned on a motorized sliding track that allows it to move radially to access every part of a disc's surface. A central motor is used to spin the disc itself.
In order to read or write information on the disc, a diode in the laser sled emits a beam of light, which the lens in turn focuses to the appropriate intensity for the task at hand. When the laser hits the surface of the disc, the data contained therein impacts its reflection.
While the polycarbonate surface of a DVD may look and feel smooth, it actually contains a spiral of physical pits arranged like grooves on a record. On top of the disc, beneath the printed label, is a reflective coating. An optical pickup inside the laser sled reads the reflections off the coating. The light scatters off the pits and reflects cleanly back into the pickup when it touches the smooth areas between the grooves, which is interpreted as binary code. The code itself is unique to the content it represents.
Most DVD drives can be used to burn or write data to blank discs in addition to reading them. Some are even designed specifically for duplicating discs with ease. This requires the use of a higher-intensity laser, which is achieved by concentrating the focus through the lens. The laser imprints the blank grooves on a writable disc with new data. Unlike commercial DVDs and other single-imprint writable formats, which have physical pits that cannot be altered once formed, rewritable discs contain a thin layer of specialized material that can render sections of the surface non-reflective, so the laser doesn't bounce back when it hits them. While it works just like the pits in the way it is read by the optical pickup, it can be altered numerous times.