Eyeglass alignment is critical to maintaining proper vision. Glass frames must rest evenly and proportionally on your ears and the bridge of your nose to keep lenses properly in line with your eyes. Check your eyeglass alignment if you notice your glasses sitting crooked on your face or the bifocal portion of your lens seems imbalanced. Aligning eyeglasses should be carried out as soon as you notice discomfort or vision impairment.
Take off the glasses and position the tip of your optical screwdriver into the head of the hinge screw. Use a Phillips screwdriver if the screw presents with a "+" indentation; otherwise use a flathead version. Turn the screw in a counter-clockwise direction to loosen.
Remove the screw and examine the thread. Replace rusted or shredded screws, as necessary. Reinsert the existing screw -- if it is still in fine condition -- or new screw into the hole. Turn the screw in a clockwise direction, using the optical screwdriver, to tighten. Ensure both hinge screws are fastened securely to keep temps and earpieces aligned.
Pinch rubber nose pieces carefully to adjust the alignment of the glasses on the bridge of your nose. Tilt nose pieces up or down, if possible, to increase alignment. Avoid applying too much pressure to prevent the nose pieces from breaking. Place the glasses back onto your face to test the alignment. Continue manipulating nose pieces as necessary.
Work with optical equipment while sitting at a table to avoid dropping and loosing tools or screws. Stand in front of a mirror. Look at the way your glasses sit on your face to see if you can notice any misalignment. Pay attention to how your glasses lean or favour one side over another. Misaligned glasses are often due to loose hinges that imbalance temps -- the long, side extensions connecting the lenses to the earpieces -- and earpieces or uneven nose pieces.