Luminescence Electromagnetic Spectrum Colors
light can be graphed in a light can be light can be Solar Spectrum Reflected Refracted
Light is reflected by mirrors or inside an optical fiber. Light is refracted as it passes through a prism. Blue light bends more than red. White light spreads As sunlight passes through the atmosphere gases into a rainbow of all colors. absorb certain wavelengths. Much solar energy lies outside the visible part of the spectrum. and its energy converted to Electricity light can be Absorbed Energy Atoms or molecules Excited State absorb energy and reach an excited state. Then they light, electricity, or release energy as light , Silicon solar cells heat electricity, or heat as they Dye sensitized solar are efficient but Ground State return to the ground state. cells and organic solar expensive. cells use chemicals to trap light. light is made of Colors after chemicals absorb energy they can if a substance absorbs light and Emit Light then emits light at a different color, that is called We can design chemicals that absorb and emit light at exactly Luminescence the wavelengths we Quantum dots in need. The color of solution fluoresce some light is invisible: fireworks comes from under UV light at adding colored light subtracting colors different elements. different colors than they absorb. They can Ultraviolet or Infrared be combined with other materials to absorb light.
Glow in the dark paint Yellow, magenta and cyan colored phosphoresces for a Ultraviolet light from a UV A radiant heater uses When red, green and blue light are inks or filters remove light to make any long time after it is lamp, or from the sun, is near infrared, a remote mixed you get white. This is how a color including black. Where there is excited by light. powerful. control uses far infrared TV makes white light. no ink the white paper shows through. radiation.
if a material is very hot visible light is part of the if electricity excites the material: and emits light, that is Electromagnetic Spectrum called Type of What it does- or is Electroluminescence EM used for if a chemical reaction Radiation Incandescence Gamma Most powerful radiation, occurs: Rays causes cancer X rays Passes through skin- Chemiluminescence The color of used to photograph the incandescent light insides of things varies according to Ultraviolet Causes sunburn – the temperature. Red damages materials is cool, white is hot. In a light stick, two Visible Colors from red to blue chemicals react light Light emitting diodes come releasing energy in the in different colors. An organic light emitting diode form of light. (OLED) uses organic chemicals. Infrared Radiant heat- used in fiber-optics for telecom, television remote control Microwave Heating food , wireless s telecom, cell phone Electromagnetic radiation is described by wavelength Radio Broadcast radio and TV Waves or frequency. Certain bands have names such as White LEDs are used for A liquid crystal display has visible, UV or infrared. The shorter the wavelength, the energy efficient lighting. red, green and blue filters more energetic the photons. over a backlight.
Researchers at the Center for Materials and Devices for Information Technology Research are designing chemicals that can control light. www.stc-mditr.org Light meets ChemistryThis material is based upon work supported by the National Science Foundation under Grant No. 0120967. Any opinions, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.