You see, light travels in a straight line and when some of the rays reflected from a bright subject pass through a small hole they do not scatter but cross and reform as an upside image on a surface parallel to the hole. This law of optics was know in ancient times. Aristotle wrote that during a partial eclipse of the sun the openings between the leaves of a tree cast images of the sun on the ground. Tuesday This week we are talking about light and a peculiar device called the camera obscura . Basically, a camera obscura is a very dark box or room with a small hole in it.
Light is reflected from outside objects through the hole.
At Montshire, our Lighthouse, located in the science park behind the building, acts as a very large camera obscura . By pulling on a rope, you can remove a shutter and see a beam of light coming through a pinhole in the wall of the Lighthouse. The light copies an exact image of outside objects upside-down and backwards on the wall across from the pinhole. You will discover that larger pinholes produce images that are fuzzy but bright, while smaller holes render sharply defined, but dimmer ones. Wednesday Montshire's lighthouse, the main topic on our program this week, is a very illuminating exhibit.