Saturday, August 4, 2007
Converging Lenses
Steps:
1.draw/choose a point on top of the object and draw 3 incident rays traveling to the lens.The first ray should be perpendicular to the lens,then draw the refracted ray that passes through the focal point.The 2nd ray should be drawn passing through the focal point,then the refracted ray should be parallel to the principal axis. . Draw the third incident ray such that it travels directly to the exact center of the lens.
2. Get the intersection of the refracted image.
Diverging Lenses
Steps:
1.draw/choose a point on top of the object and draw 3 incident rays traveling to the lens.The first ray should be perpendicular to the lens,then draw the refracted ray that passes through the focal point.The 2nd ray should be drawn passing through the focal point,then the refracted ray should be perpendicular to the object. Draw the third incident ray such that it travels directly to the exact center of the lens.
2.Get the intersection of the refracted rays.
flew into your heart at [2:21 AM]
Our eyes and the camera both has a lens. They also use the same type of lens, the converging lens. Those lenses are found in magnifying glasses, they make an image look bigger. This is why you can see the details in something even if it’s on the other side of the room. One thing about lenses is that they can only focus on things that are the same distance away from them. This is why your eyes can focus on things that are close to you or far from you; just not at the same time. Cameras are the same way . you can only focus them on things that are the same distance away.
In the camera, the lens focuses the light onto a piece of film. The film has chemicals in it that basically trap the image on it, making it permanent. Instead of film, your eye uses something called a ’retina. The retina has lots of little tiny things called ’rods’ and ’cones’ all over it. These are basically tiny antennae that tell your brain about the light that hits them. The rods tell your brain whether there is a light in a certain spot or not while the cones tell your brain of what is the color of the light percepted.
There is one spot on the retina, though, that has no antennae at all. This is the spot where the nerve leaves your eye to go to your brain. At this spot, you can’t see anything at all. That spot called your blind spot. This is one of the reasons that you have two eyes: what you can’t see with one eye you can see with the other. Unlike your eyes, cameras have no blind spot, so they only need to have one lens.
flew into your heart at [2:10 AM]