FF-4-DESKTOP

Occupational Design, Backside Digital Free-Form Progressive

Description:

Aspheric/Atoric design, combining backside free-form processing with a spherical front surface, providing occupational lens wearers with an optimized optical correction. Designed for people who spend most of their time using a computer or a desktop environment.

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Using reverse power accommodation technology, this specialized lens controls the lens power in a very precise and comfortable way. Reading is sharp and clear at 35cm and computer monitors at 50cm. Wearers will adapt instantly to the smooth transition in the wide intermediate area.

Anti-reflective coatings are highly recommended with this lens.

Specifications:

Lens Type: Backside aspheric reverse power occupational progressive
Corridor Length: 25mm (-10mm, +15mm from GC)
Fitting Point: Geometric Center
Near Power Verification: Near power only
Prism Power: Up to 3.00 diopters per pair
Refractive Index: 1.50 (CR-39), 1.59 (Poly), 1.60, 1.67
Reverse Power: Example Table Below

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Prescribing Practice:

There are three types as indicated below. Prescribing practice requires choosing between the three. Depending on the patient’s add power, choose the appropriate lens type using the tables below:

Type Reverse Power Fitting Point Power (-40% of near power)
1.0 -1.00D -0.40D
1.5 -1.50D -0.60D
2.0 -2.00D -0.80D

Prescribed Add (D) Reverse Power Type Patient’s Accommodation
0.75 Not Recommended 3.75D to 4.00D
1.00 Type 1.0 (-1.00D) 3.25D to 3.50D
1.25 Type 1.0 (-1.00D) 2.75D to 3.00D
1.50 Type 1.0 (-1.00D) 2.25D to 2.50D
1.75 Type 1.0 (-1.00D) 1.75D to 2.00D
2.00 Type 1.0 (-1.00D) 1.25D to 1.50D
2.25 Type 1.0 (-1.00D) 0.75D to 1.00D
2.50 Type 1.5 (-1.50D) 0.25D to 0.50D
2.75 Type 2.0 (-2.00D) 0.00

Lens Fitting Chart:

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