Light Waves
Electromagnetic Spectrum
Infra-Red Radiation
Infrared Radiation is emitted by all objects that are usually sensed by heat. Infrared waves are thermal. As heat increases, so does the amount of infrared radiation. There is two types of infrared. The two types are Near Infrared and Far Infrared. Infrared waves are not visible to the naked eye. Night vision goggles pick up the infrared light which is emitted by our skin and objects with heat. As seen as the image below the different parts of the body may be hotter or cooler depending on how hot the persons body temperature is.
The Electromagnetic Spectrum is a continuum of the arranged frequency and wavelength. The number of times per second a new electric or magnetic force is grated is caused by the frequency of the electromagnetic waves. Radiation is the energy that travels and spreads as it goes. The earth, the sun and other living bodies attract radiate electromagnetic energy. The energy wave types are consisted of repeating pattern of electrical and magnetic forces. There are also transverse waves with magnetic and electric forces moving in a right angle direction of the wave. The wave length increases when there is a higher frequency. In the diagram below it is shown that the waves are much larger on the left hand side as towards the right hand side.
Televison Remotes
Cancer Cells
Radiation therapy is when doctors use high energy radiation to decrease tumours and also to kill cancer cells. Gamma Rays and Rays are used to perform the radiation for cancer treatment. The radiation is delivered from a machine outside of the body or it can also come from radioactive materials which is then placed in the body near the cancer cells. These two procedures can be called external-beam radiation therapy and internal radiation therapy.
A televison remote sends out a beam of infra-red wave. The wave will send out different codes and commands. The tv receives the signal beam and changes, turns on the tv. A microchip is placed in the tv which the infra-red beam will hit the microchip. As seen in the image below the remote is sending the beam of infra-red to target the microchip that is inside the TV to turn it on or off and also to change the channel.
Refration
Refraction can occur when there change of the speed of light, that has been passes through a medium to another medium. Refraction results in a change in direction or ‘bend’. That is so the wave of light energy is bends on its way to your eye, the image you see can be quite different. An example of refraction in daily activities and sports is swimming. If you notice that the persons body is not aline. Like in the image below it is visible to see that the straw has been bent from the view of the image. This is when refraction occurs. Refraction also occurs when fishing.
The Bionic Eye
The bionic eye is developed by the BVA (Bionic Vision Australia). The BVA is a national corporation of researches that work together to develop the Bionic eye devices. The aim of the bionic eye is to help restore the sight of vision to people who's eyes have been damaged due to retinitis pigmentosa and age-related macular degeneration. The bionic eye system consist of a camera attached to a set of glasses, which transmits high-frequency radio signals to microchip implanted in the eye. Electrodes on the implanted microchip convert signals into electrical impulses. The impulses are passed down along the optic nerve to the vision processing centres of the brain, where they are interpreted as an image. Visit http://bionicvision.org.au/ for more information on the bionic eye.