title_body: Are there studies that show whether reading ebooks on e-Ink, LCD, SLCD or AMOLED displays are better for eyes? When people review different cell phones, they usually look at whether a specific display type (e-Ink, LCD, SLCD that HTC uses or AMOLED that Samsung uses) is better or worse for image quality.
  
  But is there any data - preferably medical research - on which one should be picked when choosing a cell phone when one of the main use cases is reading e-books and eye health is a consideration?
upvoted_answer: I don't know about any for those particular screentypes, but LCD vs E-ink has been researched by Siegenthaler, et al.
  
  This study showed that the objective reading behaviour is little different between the two types, but strangely (to me) the subjective preference shifted over time from a small advantage by E-ink to a small advantage by LCD.