Artificial iris automatically responds to light just like a human one
An artificial iris that responds to light in the same way as a human eye has been developed a team at the University of Tampere (TUT) in Finland.
The iris is manufactured from an intelligent, light-controlled polymer material that reacts quickly to different light intensities.
The iris in the human eye is a tissue that regulates the amount of light coming into the eye by changing the size of the pupil in order to ensure high-quality vision.
Controlling the amount of incoming light is just as important to imaging applications, such as cameras.
However, these applications require complicated control circuitry and light detection schemes to adjust the amount of incoming light and produce high-quality pictures.
“An autonomous iris that can independently adjust its shape and the size of its aperture in response to the amount of incoming light is a new innovation in the field of light-deformable materials,” said Arri Priimägi, head of the research group.
The artificial iris was manufactured from light-sensitive liquid crystal elastomer. Its manufacture utilised the so-called photo alignment technology that is also used in some contemporary mobile phone displays.
“The artificial iris looks a little bit like a contact lens, and its centre opens and closes according to the amount of light that hits it,” Priimägi said.
What makes this invention significant, he believes, is the device’s ability to function autonomously, free from power sources or external light detection systems.
“This research was inspired by Dr Kaczmarek, who is an ophthalmologist and foresees potential use for a self-regulating iris-like device in the treatment of iris defects.
“The road to practical applications is long, but our next goal is to make the iris function also in aqueous environment. Another important goal will be to increase the sensitivity of the device in order to make it react to smaller changes in the amount of incoming light. These developments will be the next steps towards possible biomedical applications,” Priimägi said.
A team of London researchers are currently exploring ‘silicon retinas’ and how they could be made to function as effectively as the real thing in order to help develop systems to monitor dangerous environments without the need for human intervention.