New Camera Sensor Eliminates Need for Flash
No flash? No problem. A new imaging sensor could soon make it possible for photographers to take clear, sharp photos, even in dim lighting.
Created by a team of researchers at Nanyang Technological University (NTU) in Singapore, the new sensor is highly sensitive to both visible and infrared light, which means it could be used in everything from the family Nikon to surveillance and satellite cameras.
The sensor, which is 1,000 times more sensitive to light than the imaging sensors of most of today's cameras, gets this high photoresponse from its innovative structure.
It's made of graphene, a super strong carbon compound with a honeycomb structure that is as flexible as rubber, more conductive than silicon and which resists heat better than a diamond.
Graphene, which is a one atom-thick layer of the mineral graphite, has already earned a reputation as the building material of the future. Andre Geim and Konstantin Novoselov took home the Nobel Prize in physics in 2010 for their work with the compound.
The inventor of the new sensor, Wang Qijie, an assistant professor at NTU's School of Electrical and Electronic Engineering, said this is the first time that a broad-spectrum, high photosensitive sensor has been made using pure graphene.
"We have shown that it is now possible to create cheap, sensitive and flexile sensors from graphene alone," said Wang. "We expect our innovation will have great impact not only on the consumer imaging industry, but also in satellite imaging and communication industries, as well as the mid-infrared applications."
Wang said the key to his new sensor is the use of "light-trapping" nanostructures that use graphene as a base. The nanostructures hold onto light-generated electron particles for much longer than conventional sensors.
This results in a stronger than usual electric signal, which can be processed into an image, like a photograph captured by a digital camera.
Most of today's camera sensors use a complementary metal-oxide semiconductor as a base. But Wang said that his graphene base is far more effective, producing clearer, sharper photos.
And, according to Wang, he even took current manufacturing practices into account when designing this new sensor. In principle, the camera industry will be able to keep using the same process to make its sensors, but simply switch out the base materials for graphene.
If the industry chooses to adopt his design, Wang said it could lead to cheaper, lighter cameras with longer battery lives for all.