THE WORLD'S ADVANCE 



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the fact that each orb sees the scene 

 from a different point. These double 

 images are blended and produce, a sin- 

 gle impression upon the mind. This is 

 what is called the stereoscopic effect of 

 double vision. Mr. Troeger eliminates 

 the flatness of the ordinary moving pic- 

 ture by means of his screen's vertical 

 ribs. These prisms give slightly over- 



be effectively displayed at any hour. 

 Open-air shows, that cannot now begin 

 until dark, may operate early and late 

 to the advantage of both the public and 

 the proprietors. The public lecturer 

 should find this new screen a great aid, 

 for instead of talking into a darkened 

 hall he will hereafter be able to see his 

 audience and to respond more sympathet- 



Two Views of the 

 New Motion Picture 

 Screen and its In- 

 ventor. 



lapping or double images, and the re- 

 sult is a sense of realism and depth, 

 as the eyes interpret them, 



The inventor's first aim was to ob- 

 tain a material with just enough faint 

 cloudiness to catch the light beams 

 and to reproduce the picture, yet 

 sufficiently translucent to allow the 

 rays, but feebly dimmed, to pass right 

 on through to the eyes of the observer. 

 After much experimenting, Mr. Troe- 

 ger found that he could build up the 

 desired translucent substance upon a 

 suitable foundation of silken mesh, 

 and now he can make in this way 

 screens of any size. Up to date, the 

 largest he has turned out are 18 by 

 20 feet. 



Apart from the ordinary field of en- 

 tertainment, he now looks to daytime 

 advertising as a further direction of 

 valuable employment. Where electric 

 signs serve their purpose only after 

 nightfall, movies, designed for the same 

 end and using the Troeger screen, could 



ically to the mood evidenced by their 

 faces. In educational work, much may 

 be gained by the improved sharpness of 

 the pictures and, for students engaged 

 upon technical subjects, exact reproduc- 

 tion is very important. As we have seen, 

 the screen eliminates or greatly reduces 

 abrupt foreshortening. 



