American Buddhismâs numbers are booming. Published just over three years ago, an American Religious Identification Survey survey showed that from the years 1990 to 2000, Buddhism grew 170 percent in North America.
However, for a lens, a positive image distance implies that the image is located on the opposite side as the object. Virtual images are formed by concave lenses or by placing an object inside the focal length of a convex lens. The ray-tracing exercise is repeated for the case of a virtual image. In this case the virtual image is upright and shrunken. The same formula for the image and object distances used above applies again here.
The image will be inverted, reduced in size, and real. Quite conveniently, the cornea-lens system produces an image of an object on the retinal surface. The process by which this occurs is known as accommodation and will be discussed in more detail in the next part of Lesson 6. Fortunately, the image is a real image-formed by the actual convergence of light rays at a point in space. Vision is dependent upon the stimulation of nerve impulses by an incoming light rays. Only real images would be capable of producing such a stimulation.