The Perifocal-Ps lens is intended for multi-factor therapeutic effects on the eye and the visual system as a whole in order to prevent the development of myopia in children with myopia predictors. The Central refraction range of the Perifocal-Ps lens is from +0.75D to 0.0D, with a cylinder up to 4.0D. The Perifocal-Ps lens, as well as the Perifocal-P lens, has an asymmetric progression on both sides of the optical center horizontally, but the value of the nasal (towards the nose) progression is higher and is 2.5D and has an earlier beginning of the progression at 4.5mm from the optical center and a faster saturation of the progression at 24mm from the optical center horizontally. In turn, the value of the temporal (towards the temple) progression in the Perifocal-Ps lens is also stronger and equal to 3.0D with an earlier start of the progression at 3mm from the optical center and a faster saturation of the progression at 24mm from the optical center horizontally. Also, unlike the Perifocal-P lens, the Perifocal-Ps lens is divided into right and left. On the front surface of the lenses there is a visible yellow marking with the designation of its optical center and horizontal (as well as on the lens Perifocal-Ms).
The Perifocal-Ps lens can have a zone for supporting accommodation and this type is designated as Perifocal-Psa