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What Semi Finished Lens Blanks Can do?
Spectacle lenses production units that transform semi-finished lenses into finished lenses according the precise characteristics of a prescription.
The customization work of laboratories enables us to provide a wide variation of optical combinations for wearer needs,
especially as regards the correction of presbyopia. Laboratories are responsible for surfacing (grinding and polishing)
and coating (coloring, anti-scratch, anti-reflective, anti-smudge etc.) the lenses.
What is a freeform lens?
"A freeform lens normally has a spherical front surface and a complex, three-dimensional back surface which incorporates the patient’s prescription. In the case of a freeform progressive lens, the back surface geometry includes the progressive design. The freeform process utilises semi-finished spherical lenses which are readily available in a wide range of base curves and indices. These lenses are accurately machined on the back side using state-of-the-art generating and polishing equipment to create the exact prescription surface.
• the front surface is a simple spherical surface
• the back surface is a complex three-dimensional surface
Technology for freeform lenses
• Provides the flexibility to offer a wider range of high level products, even for the smaller optical laboratory
• Only requires a stock of semi-finished spheres in each material from any quality source
• Lab management is simplified with significantly fewer SKUs
• Progressive surface is closer to the eye - providing broader fields of view in the corridor and reading area
• Accurately reproduces the intended progressive design
• Prescription accuracy is not limited by the tooling steps available in the laboratory
• Accurate prescription alignment is guaranteed