Interpretation of surrounding environment using light which is reflected by the objects is known as visual perception or human vision. Large number of people around the globe experience weak eyesight due to many reasons. For a very long time, wearing glasses of correct power are being used to correct the vision. More recently contact lenses are becoming popular. Contact lenses are thin lenses made up of water absorbing polymer (hydrogel) which are placed directly on the surface of the eye.

Latest advanced technologies have successfully made various smart electronic glasses (Google Glass is one popular example). Now, next obvious progression in the area is smart electronic contact lenses that will include features like - A super human vision, Heads up displays, Video cameras, Medical sensors, LED or LCD, Self assembly technique and an Antenna

This smart contact lens is like a regular polymer lens but it contains electro active material (electric field covered by a layer of liquid crystal material) that allows wearers to adjust the optics at near, far and intermediate distances for focusing. They can also change the focusing power. This technology also works in various optical devices like augmented reality displays or focusing eyeglasses. Electrodes which are present in the electric field in the lens activates the liquid crystal layer and create various shapes like hyperopic, myopic and aspheric in a lens. The wearer can choose pre-set focus ranges to change prescription quickly, to adapt to different viewing situations as they arise.

RF energy in the lens is collected from different portable transmitter by the means of antenna. Display control circuit driven by DC power collects all the visual information. LED/LCD display is placed at the center position for display and its transparency is modulated by a control circuit. A large capacitor which acts as an energy storage module is connected to a solar cell and act as power source.

User experiences augmented reality wearing this lens. Lens contains miniscule display, camera and antenna fitted inside it. Number of sensors present inside it can detect the eye movement and blinking using which the display can be controlled. The main advantage of such a lens is that it provides much better image quality than that of existing smart glasses and is less bulky.

Here are a few applications and advantages of smart lens

• A smart lens basically enhances or improves the vision. Inside this new artificial lens there exists storage, battery, sensors, a radio and other electronics.
• This lens will change the focal length of a lens in a fraction of a seconds depending upon the need of eye thus solving many eye problems like near sightedness, far sightedness etc.
• Soldiers can have the ability to see in dark with thermal imaging using this lens.
• Smart contact lenses could record video which can be controlled by blinking of eyes. Piezoelectric sensors could be used which can convert eye movement into electric power.

By:- Himani Chugh - Asst. Prof. ECE, Chitkara University H.P.

References

1. http://www.computerworld.com/article/3066870/wearables/why-a-smart-contact-lens-is-the-ultimate-wearable.html
2. http://www.sciencealert.com/samsung-just-patented-smart-contact-lenses-with-a-built-in-camera