Due to the exotic freeform surface exhibited by Progressive Addition Lenses, a new characterization approach that takes into account the projection of the eye pupil over the lens is required. In this work, a locally resolved description of the performance of the lens has been obtained by calculating the Modulation Transfer Function (MTF) for uniformly spaced subaperture positions. This quality metric is conveniently suitable to characterize imaging systems, because it describes the contrast resolving capabilities of the lens as a function of the spatial frequency. In addition, it is independent of the eye perception of the test engineer. The MTF has been indirectly calculated using Experimental Ray Tracing, by extracting the values of the ray slopes of each subaperture from the complete ray traced data. By following this procedure, two-dimensional maps are generated using two different criteria. The first criterion is based on the determination of the normalized spatial frequency where the MTF has declined by 50 %. The second one uses a simplified Strehl ratio. Also, the results for different subaperture diameters are obtained without the need for changing the setup or repeating the measurements.
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