Delta Bifocal - A Distance Lens with built in Reading Glasses
Delta is the lens design for the patient who demands great quality distance vision and a high near demand. The variable segment height means the optics can be positioned correctly in cases where lenses ride high or low or there is asymmetry in the fitting between right and left eyes.
Delta Bifocal Parameters
- BOZR: 6.80mm to 9.50mm
- Diameter: 9.50mm or specify
- Power: ±20.00D
- Add Powers: 0.75 to 4.00
- Segment: Standard Low (1.5mm below), High (on HCL) or specify
- Back Surface: CC or specify (toric unavailable)
- Prism Ballast: 1.5Δ or specify
- Material: Specify
A simple blink is all it takes to focus between distance and full near correction. Fitting of the delta is simple and can be assessed with a direct ophthalmoscope. Visualising the near segment enables the fitting to be tailored to your patient. This provides optimum visual performance and satisfaction. The translation effect from the lens means even patients with small pupils can a focus change not possible with other designs. The design might well be over 10 years old but it is still popular for the simple reason it works well.