Variable Aperture Control Could Be Nokia’s PureView 3.0 Innovation for Lumia Cameras
Nokia, which has long innovated on camera technology for mobile from its N-series Symbian smartphones through its Lumia 920 flagship today, may be introducing a variable aperture camera control as part of its next-generation PureView technology for future smartphone cameras on the Lumia range. The variable aperture control was discovered as part of a patent that Nokia had filed and been awarded.
The company had focused on cramming an extremely large photo sensor packed with 41 megapixels on the Nokia 808 as part of its PureView 1.0 technology. PureView 2.0 debuted on the Windows Phone-powered Lumia 920, focusing on image stabilization for video and low light photography with a standard 8-megapixel camera sensor. And it looks like a variable aperture control could be the defining feature of what could amount to PureView 3.0.
A variable aperture could help, especially when coupled with a large sensor and good camera optics like those on the Nokia 808, create even more professional looking images with greater control on subject matter isolation and background blur. In essence, portraiture would benefit as well as a variety of other types of shots where users could focus on one subject in the scene and blur out either the foreground or background to help the viewer of the picture focus on what the photographer sees as important. This is possible with a large aperture, but the problem is that large apertures may let in too much light on a bright day, so filters would be applied to reduce the light. This is what’s essentially done on the Nokia 808, but users don’t have control on how much blur or focus they can have readily. Smaller apertures would be used in landscape photography to keep everything in focus.
Nokia writes of the benefits to aperture control:
Small aperture with high f- number increases the sharpness of distant objects, or in other words, increases depth-of-field, which means more elements of a picture, from foreground to background, become sharply focused. This can create a distinct sense of depth to a photograph, drawing the viewer into the picture. It is well-known that small apertures are used especially formost landscape photographs.
The large aperture produces shallow depth-of-field, which means the area of sharp focus in the picture will be small. It is well known that small apertures are used especially for isolating the subject of the picture while throwing the background and other distracting elements out of focus. Some useful applications of large apertures include portraits and wildlife close-ups.
On the Nokia 808, blurring of the background, or applying bokeh in photography lingo, can be achieved mostly with macro shots where users aim the camera close to the subject. This is done, for example, when shooting flowers, floral petals, or insects, and for the most part many modern smartphone cameras can do this as well.
To control aperture, Nokia will use electrodes to control a ring that can be activated with a charge of electricity:
The invention relates in general to the field of digital cameras, especially small digital cameras. In particularly the invention relates for adjusting an aperture for mobile cameras. The adjustable aperture construction of the invention comprises two electrodes, and an electrical circuit for applying a voltage to the electrodes in order to create an electric field between the electrodes. In addition the construction comprises between the electrodes a center unit with a hole in the middle of it, the center unit being made of an electroactive material, such as dielectric material or electrostrictive polymer. The aperture can be adjusted by deforming the shape of the center unit. The shape of the center unit is advantageously deformed by the electric field created between said electrodes by said electrical circuit.
Nokia has applied for a patent on the technology, which is being reported by Nokia Power User, and it’s unclear when we’ll begin seeing this technology.