Samsung files patent for liquid zoom lens
By Alan Brandon
November 7, 2010
Samsung has filed a patent for a new type of liquid lens that provides not only autofocus capability, but also true optical zoom capability. Liquid lenses, with their small form factor and lack of motors or moving parts, are ideal for use in compact cameras, phones, and other mobile devices. Where a conventional liquid lens may provide only autofocus, Samsung’s design uses two separately controllable liquid lenses in a single array to provide both functions.
The demand for more features packed into smaller mobile devices continues to grow, and liquid lens technology has become more common over the last five years. Liquid lenses are suitable for use not only in cameras and phones, but in web cams, bar code scanners, medical devices such as endoscopes and dental cameras, and machine vision devices. We have previously reported on liquid lenses from Philips, A*STAR IMRE, and even Samsung’s earlier development efforts with Varioptic.
A liquid lens is basically a small amount of one or two types of fluid in a small chamber. Similar to a drop of dew magnifying a blade of grass, the fluid acts on light passing through the chamber. Using liquids that don’t mix (such as oil and water) allows the lens to contain optical layers. The shape of the fluid layers can be changed using a small electric current, thereby changing the optics of the liquid lens.
The advantage of liquid lens technology is that there are no moving parts or focus motors needed. And with no motors, the lenses are faster and quieter than traditional mechanical lenses. In addition, liquid lenses are smaller and lighter than glass or plastic lenses. These are obviously important characteristics, as manufacturers continue to design better cameras and more features into their mobile devices.
While conventional liquid lenses are useful for autofocus applications, they typically require an array of solid lenses to provide zoom capability, according to the patent documentation filed by Samsung. This type of liquid lens zoom array is smaller than a solid-lens array, but still takes up valuable space in compact mobile devices.
The Samsung design is essentially two liquid lenses stacked together, each with separate controls. Having two liquid lenses allows for one to handle autofocus duties and the other to perform the optical zooming. Each liquid lens is made up of layers of electrolytes and insulating fluid and each is controlled separately by its own electrode.
There is no word yet on when we will begin to see the new Samsung technology in consumer devices.
Via: Free patents online