Brief answer....It does take few weeks Detailed answer... Hello, Thanks for the query. It does take a while to get used to the non progressive trifocal lens ( because of that narrower middle lens ),but eventually it does happen and soon you get to the point where you don't even notice the lines. Basically trifocals have an additional ribbon shaped lens segment immediately above the near segment for seeing objects in intermediate zone of vision - appox. 18-24 inches away. Typically intermediate segment contains 50% of added magnification of near segment and restores clear vision for arm's length tasks such as computer work,reading a newspaper,seeing the car dashboard etc. It needs some practice to view through trifocals. Do the following for better viewing... Adjust the height of your computer monitor so that you don't have to move your head to view the screen Instead of moving your eyes,move your head to look at the objects.This helps in prevention of dizziness. Do practice to look at objects which are at different distances from your eyes,like.. From top section to look at distance From middle section to look at computer From lower section for reading purpose. I hope it helps however you may revert to me for any further query. Best of luck Thanks

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