The human eye has an approximate angular resolution of phi = 5.8 xx 10^(-4) rad and a typical photprinter prints a minimum of 300 dpi (dots per inch = 2.54 cm). At what minimal distance z should a printed page be held so that one does not see the individual dots ?

The human eye has an approximate angular resolution of phi = 5.8 xx 10

1.	The human eye has an approximate angular resolution of phi = 5.8 xx 10^(-4) rad and a typical photprinter prints a minimum of 300 dpi (dots per inch = 2.54 cm). At what minimal distance z should a printed page be held so that one does not see the individual dots ?
Answer» 10 CM 12.5 cm 13 cm 14.5 cm Solution :The linear distance between two dots is `L = (2.54)/(300) cm APPROX 0.84 xx 10^(-2) cm` At a distance of Z cm this subtends an angle. `phi -l/z therefore z = (l)/(phi) = (0.84 xx 10^(-2)cm)/(5.8 xx 10^(-4)) approx 14.5 cm`.

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The human eye has an approximate angular resolution of phi = 5.8 xx 10^(-4) rad and a typical photprinter prints a minimum of 300 dpi (dots per inch = 2.54 cm). At what minimal distance z should a printed page be held so that one does not see the individual dots ?

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