REFLECTION 



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REFLECTION 



Kind of Images. There are two kinds of images, real and 

 virtual images. The real image is the image which* is actually pro- 

 duced by a lens or mirror, and can be found on a screen. The images 

 caused by cameras, lenses, by the eye, by moving picture apparatus 



FIG. 196. How Pepper's Ghost is produced. 



Tower, Smith and Turton Physics. 



and projection lanterns are real images. A virtual image is an 

 image which cannot be found on a screen. Such images are pro- 

 duced by plain mirrors. When a person looks into a mirror an 



FIG. 197. How the moon sends us its light. 



image is seen, apparently behind the mirror. There really is no 

 image 'behind the mirror. 



The optical illusion called Pepper's Ghost is produced by the 

 use of a virtual image. The room is darkened. 



