This standard applies to the processing of all prescription ophthalmic spectacle lenses in edged or assembled form. It is a processing guideline for optical laboratories applicable to prescription eyewear prior to transfer for dispensing@ and for the dispenser prior to the delivery of the finished eyewear to the patient. Relevant optical specifications and tolerances of this standard should apply also to uncut lenses supplied by an optical laboratory to be used in filling a specific prescription. This standard does not apply to products covered by American National Standard for Ophthalmics ?C Nonprescription Sunglasses and Fashion Eyewear - Requirements@ ANSI Z80.3-2001. 1.2 Purpose This standard reflects the shift in utilization from mass-produced lenses to a basic dependence upon custom-processed lenses at the laboratory level. It does not represent tolerances that describe the state-of-the-art of the ophthalmic laboratory@ but provides quality goals for new pristine lenses prepared to individual prescription. The individual performance parameters listed in this standard can be achieved reliably. However@ it is difficult to meet all of the requirements simultaneously in any given lens or mounted pair. The fact that@ under rigorous application of this standard@ a significant number of spectacles (approximately 25%@ based upon industry data) will not achieve all parameters simultaneously@ must be accepted as a reflection of the state-of-the-art (see Annex E ?C Optical Index). As such@ this standard expresses desirable technical concepts that provide a frame of reference for safety and effectiveness and is not designed as a regulatory instrument.