HALFTONE SCREEN — KAINEN 



419 



ference in Moss's case was that he added numerous refinements and 

 was able to achieve good results with a heretofore unsuccessful 

 process. 



During the 1880's greater efforts than ever before were made to 

 perfect letterpress halftone, or at least to obtain passable results 

 to satisfy the increasing demand for illustrations in newspapers and 

 magazines. Among the processes that achieved a moderate degree 

 of commercialization was the Luxotype, patented in England in 1883 

 by Brown, Barnes, and Bell. This process had several variations, 

 but in its most widely used version a fine wire mesh was pressed 

 into a moist photograph, embossing and roughening it uniformly. 

 Under a strong oblique light the cross-lined shadows were deepest in 

 the dark areas and lightest in the pale sections. A negative was 

 made, intensified, and printed. The photograph was then used to 

 make line copy. Needless to say, results were coarse but seemingly 

 adequate for certain types of publications. 



VAVAVV 



4 4 4 ♦ ♦ ♦.♦ ♦ 



Figure 1. — Drawing of halftone screen, greatly enlarged. 



The perfection of the halftone screen as we know it today was the 

 result of work carried out independently but at about the same time 

 by Frederick E. Ives and the Levy brothers, Louis and Max, in Phila- 

 delphia. Ives in 1885-86 successfully sealed two single-line screens 

 together at right angles and worked out the relationship of screen dis- 

 tance and focal length. His notion of the "optical V," wherein each 

 aperture in the screen becomes a separate lens admitting varying de- 

 grees of light, is still the foundation for modern process work. Ad- 

 mittedly some of his ideas were known before, but it seems incontro- 

 vertible that Ives first stated them in clear terms and made it possible 



