Pop-Sci Core77 Design Challenge/ Description
HUMAN POWERED
10/20/03



Description of Design

Blink Powered Nigh Vision Contact Lenses


The blink powered night vision contact lenses allow a person to see clearly in low- light environments by enhancing ambient light up to 200 per cent. These lenses use plasma technologies to eliminate the cumbersome and expensive image-intensification tubes used in convention night-vision goggles. The advantages of using the contact lenses above night-vision goggles are 1) full peripheral vision, 2) more comfortable interface, 3) a more cost-effective system, and 4) less disorientation with use.

Conventional night vision goggles use an image- intensification tube that amplifies low levels of light. Low levels of ambient light pass through a photocathode that converts the light photons to electrons, which are in turn amplified over a distance. The electrons, while maintaining their orientation, then collide with a phosphor screen where they are converted into visible light. This technology is similar to a conventional picture- tube television screen where an electron beam bombards a phosphor screen to produce a picture. The disadvantage to both these systems is that the electrons have to pass some distance to produce a picture- hence the long tube on most night-vision goggles and the long depth of conventional television sets.

The Night-Vision Contacts (NVC) uses a three-layered technology very similar to plasma screen televisions that allows for their thin design. To achieve the necessary electric charge to carry out the amplification of light a thin layer of neodymium-iron-boron (NdFeB) gel is applied to the outer eyelid. NdFeB is the strongest rare earth magnet that exists today and provides the magnetic field necessary to produce an electic charge on the surface of the contact lens. When a person blinks, the NdFeB layer charges the ferro-magnetic surface of the contact lens that is now excited with charged particles. Ambient light photons and some infrared light photons collide with the charged surface that sends charged particles into the thin plasma layer of the contact lens. These charged particles and light photons collide with electrons within the plasma layer. The electrons, in the collision, are forced to a higher atomic orbit. The electrons quickly return to their natural orbit and in doing so release ultra-violet light photons. The UV photons then pass into a phosphor screen and are converted into visible light.

The night vision contact lenses hold a very powerful charge for a short period of time, but they are continuously recharged with every blink. Conventional night-vision goggles need an average of 5,000 volts of electricity provided by two AA batteries. Batteries lose their charge very quickly and the difficulties of changing those batteries in a low-light environment are obvious. The night-vision contact lenses remain charges and functioning at their optimal performance as long as their user keeps blinking. And because the night-vision contacts rest on the surface of the eyeball, there is no disorientation and no loss of peripheral vision.