Nothing causes instant damage. (See Into the Sun for an interesting take on it) The question then comes, how much exposure will damage your eyes. The Straight Dope has a very good article on this: Can laser pointers damage your eyes? As does Scientific American: Can a pocket laser damage the eye? The big take is that (until recently) the most powerful laser pointers available would cause you to blink before it would do damage to your eyes (about 0.25s).
Importance of the sun. - Sun = ultimate source of E for all organisms-The energy from sunlight is stored in the chemical bonds of molecules. - When these bonds are broken, energy is released-Same for all fuel sources (food, fossil fuel, biofuel).
Nonrenewable Sources of Energy. Most of the energy we use comes from fossil fuels, such as coal, natural gas and petroleum. Uranium is another nonrenewable source, but it is not a fossil fuel. Uranium is converted to a fuel and used in nuclear power plants. Once these natural resources are used up, they are gone forever.