My eyes went from -1.00 and -1.25 to -2.25 and -2.75. Not sure what type of lenses I need. Should I get plastic or this new type called polycarbonate?
  
  The assistant at the optical store said I need the polycarbonate because of how bad my eyes are but they're more expensive so I wanted a second opinion.
  
  Also, are my eyes really a lot worse? Is this legally blind?
  Read more: Prescription increased by a lot in both eyes what lenses do I need?