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Progressive Lenses

Astigmatic areas (in gray) are out of focus.

 

 

 

 

 

 

 

 

 

 

 

 

 

 


Adjustment to progressive lenses is usually regarded as easy, however one of the difficulties inherent in progressive glasses is reduced peripheral vision because the undistorted focal area for both eyes is a narrow vertical range.  (See diagram above.  The gray areas indicate reduced peripheral vision.)  Objects outside of the undistorted vertical focal area range are fuzzy or distorted.    This "Robo-Cop" effect requires the wearer to directly look at the object and move your head up or down to bring it into focus and significantly impairs peripheral vision.

 

Colors are also distorted when seen from outside the central clear vision area

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


Other complications and distortions occur when lenses are too far forward, too close to the eyes (usually caused by misaligned nose pads), tilted too far forward or backward (usually caused by a skewed frame), or the distance between the vertical focal areas of the eyes is not aligned with the focal point of the eyes (usually caused by an inaccurate separation of the lenses). 

 

When wearing progressive glasses and attempting to view larger text letters, the loss of peripheral vision frequently makes concepts virtually unintelligible.

 

Dyop™ Peripheral Distortion Test

Requires (free) Adobe Flash to run

Provides a quantitative measure of the loss of peripheral vision.

 

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