XPost: sci.med   
   From: hwabnig@.-   
      
   On Tue, 21 Jun 2011 12:05:43 -0400, Eric    
   wrote:   
      
   >Quick question about progressive lenses:   
   >   
   >I've had progressives for many years. No problems. Uniform focus   
   >side-to-side with no noticeable distortions.   
   >   
   >Just got new progressive lenses, and I've had tons of problems. First   
   >pair had a "Fun House Mirror" look; objects would shift and distort as   
   >I turned my head. The optometrist had new lenses made. The new pair   
   >does the same, but to a lesser extent.   
   >   
   >I think the primary problem is that the critical area of the lens is   
   >done in a narrow vertical strip. There is distortion to the left and   
   >right of that extremely narrow zone. Looking at a line of text on my   
   >computer monitor, the center is readable. The two ends of the line are   
   >blurred. So I have to physically turn my head to read on-screen text.   
   >   
   >And as mentioned, objects shift as I turn my head. This is easy to see   
   >with vertical lines. They lean left and right, depending. This is so   
   >extreme that at times, I've actually thought that something was   
   >falling over.   
   >   
   >The optometrist's assurances that "This is normal" would be more   
   >believable if I hadn't already had progressive lenses that did not   
   >exhibit any of these problems. The previous lenses were actually a bit   
   >-stronger- than the current ones, so it cannot be attributed to a   
   >difference in prescription.   
   >   
   >Any ideas? Are there certain lens vendors that have this problem?   
      
   Here in my area they sell 3 classes of progressive lenses,   
   priced normal, expensive and hilarious expensive.   
   The difference is in the center vertical area width.   
   Cheap glasses force you to scan a computer screen with head   
   movements from left to right.   
   With my glasses, the hilarious ones, I just move my eyes around.   
   I have the direct comparison with a relative who bought at an optics   
   discounter.   
      
   Asking the optician why the prices and why 2 classes with bad quality,   
   when the production process forall 3 is exactly the same, done on   
   the same machine, in the same time, got no answer.   
   But I can figure it out myself.   
      
   Most opticians do it wrong anyway. Upper rim of the glasses must be   
   corrected for 3 meters, to see the secretary when she enters the room,   
   lower rim must be corrected for 40 cm to see the keyboard   
   (I am a blind-typist, not looking at the screen when typing)   
   and the center must be 70 or 80 cm for looking straight   
    at the LCD screen.   
      
   w.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)