What should I do? Adjust my 19-inch monitor or change to a 17-inch? Are there any theories about the optimal size monitor for human eyes?

 

logo Why Do My Eyes Feel More Easily Tired When Using A 19 inch Lcd Monitor Than A 17 inch One?
Dell 190SB LCD Flat Panel 17 19 Monitor Stand 190SB
Dell 190SB LCD Flat Panel 17 19 Monitor Stand 190SB
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DELL WINDOW XP HOME EDITION 17 INCH SCREEN INCLUDE DESK TOPMONITORSPEAKEERS
DELL WINDOW XP HOME EDITION 17 INCH SCREEN INCLUDE DESK TOPMONITORSPEAKEERS
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Samsung SyncMaster 170MP 17 LCD Monitor with TV Tuner
Samsung SyncMaster 170MP 17 LCD Monitor with TV Tuner
Paypal   US $.01