Ultraviolet <---- Visible Spectrum (350-780 nanoseconds) ----> InfraRed

Gamma Rays:

• The highest energy electromagnetic waves (or photons) are the gamma rays.
  
  
• Application:Many nuclear reactions and interactions result in the emission of
  gamma rays. We can take advantage of these interactions for
  medicinal purposes, especially in cancer treatments, where
  focused gamma rays can be used to eliminate malignant cells.
   
• Application:Distant galaxies are also prodigious sources of gamma rays,
  where they are thought to be produced by very hot matter falling
  onto a massive black hole in the center of the host galaxy. Our
  atmosphere shields the Earth from most gamma rays produced in
  deep space.

• Thewavelengths of these photons range from about 10^-8m to
  10^-12m
• The first discoverer of X-rays was Wilhelm Röentgen, a German
  physicist who, in 1895, accidentally found these "light" rays when
  he put a radioactive source in a drawer with some unexposed
  photographic negatives and found the next day that the film had
  been exposed somehow! The radioactive source had emitted
  X-rays and produced bright spots on the film.
• Application:X-rays are often used in medicine to see inside the body, without
  invasive surgery. The easiest method is to simply use
  photographic paper behind the target (the body) and shine
  X-rays through the target onto the film. Because the bones are
  much denser than the rest of the tissue, the X-rays don't get
  through them as well, so the bones show up as a dark areas on
  the negative film. The rest of the tissue is relatively transparent to
  the X-rays and show up as light areas on the film.

• The nearest high-energy neighbor to visible light is the
  ultraviolet (UV) region
• The sun is a strong emitter of UV radiation, but fortunately for
  us, the Earth's atmosphere shields its inhabitants from the sun's
  harmful UV light. In the upper atmosphere lies the ozone layer,
  where most of the UV radiation is absorbed.
• Application:  Involved in photosynthesis for a number of plants

Visible:

• Occupying a very small part of the entire electromagnetic
  spectrum, the visible light region is the only range of energies
  that human eyes can detect.

• Just below (or just above, depending on which way you look at
  it) the visible spectrum is infrared (IR) radiation. These are
  longer wavelength light rays (about 1.00 mm to 8 x 10-7m, or
  80,000Å)
• Many molecules tend to resonate or vibrate easily when exposed
  to IR radiation, so we erroneously think of IR as heat waves.
  The sun emits about half of its radiation in the IR and even home
  light bulbs emit more IR than visible light.
• Applications:
  • Many devices use IR as a means of transmitting information (IR
    lasers, TV remote controls) and of receiving signals (IR
    telescopes, photographic films, satellites).
  • In order to "see" at
    night, IR goggles pick up the weak infrared radiation from our
    warm bodies, translating the signal into visible light that our eyes
    can detect.
  • Astronomers use IR telescopes to see inside and beyond huge
    clouds of gas and dust that block our (visible light) view of such
    places as the center of the Galaxy.
  • Art preservationists use IR cameras to view paintings that might have underdrawings not
    visible with the human eye

Microwave:

• Microwaves is a misnomer. There's nothing "micro" about them,
  in the scientific sense, which says that micro means "one
  millionth". The wavelength range of this radiation is about 3.0 cm
  to 1.0 mm
• Application:Besides ovens, we use microwaves for many kinds of
  communication. Most television satellites and dishes operate in
  the microwave region, and any kind of radar device is emitting
  and receiving microwave signals. Short-wave radio operators
  are using microwaves to talk to each other around the world,
  because these waves can travel much further than weak radio
  waves.

• UHF stands for ultra-high frequency and VHF
  means very-high frequency. Considering the very low energies of
  these waves (10-7eV to 10-5eV) which corresponds to a very
  low frequency, it's hard to understand why someone called them
  "ultra-high" and "very-high". UHF and VHF waves are
  essentially just a-little-higher-energy radio waves.
• Application:  Your standard television antenna (the one with the horizontal
  metal rods, not the satellite dish) receives VHF and UHF waves
  from the local television stations. The reason for the long rods?
  Since these waves have wavelengths of a few centimeters to a
  few meters, the electrons in the metal of the antenna need to be
  able to vibrate with the same wavelength in order to "pick up"
  the signal. Bunny ears on your old TV set usually aren't as long
  as the rods on your roof-top antenna, so your reception
  probably isn't as good. Plus, the metal in your house tends to
  block and distort the signal, whereas non-conductors easily pass
  the waves. Humans, on the other hand, act as a good conductor
  for many TV waves, thus touching the antenna helps with the
  reception.
   

Radio:
 

• The longest wavelength and smallest energy electromagnetic
  wave (or photon) is the radio wave
• Applications:
  • AM signals are transmitted by radio and television stations
    between 535 kHz and 1605 kHz, but can be picked up by
    almost anything from standard telephones to orthodontia.
  • A possible frequence of a radio station might be to
    transmits its signal is 91,500,000 Hz (Hz stands for Hertz, a unit
    denoting cycles or waves/s). We know this as 91.5 MHz. This is
    a frequency-modulated signal (FM) in which the frequency of the
    waves are combined with the amplitude (the information) to
    create the signal and eliminate noise, the major downfall of
    amplitude-modulated (AM) signals.

The spectrum of a light source shows is the distribution of light energy vs. wavelength (lambda).

White Light = all visible wavelengths

Here we can see the white light splitting into the spectrum using a prisim.

1. Brightness. = the amplitude of the spectrum.
   • brightness adaptation:
2. Hue. Informally refered to as color.
   • frequency componets of spectrum
   • characterized by dominant frequency
   • wavelength DOES NOT equal hue.
3. Saturation. Spectral width, describes "whiteness" of a color
   • unsaturated = a lot of white
   • saturated = no white

• Emitted Light
  • The light from a monitor or projector. The primary hues are green, red, and blue. "Combining" any two opposite colors = white.
• Reflected Light
  • Primary hues are yellow, cyan, and magenta. "Combining" opposites = black.