The gradual increase in space between the cornea and lens surface, has a very favourable effect on the flow of tear fluid behind the contact lens. This effect makes Tetra a valued and successful contact lens. The periphery of the lens is about 1.00 mm wide. The Tetra lens can be used well with a normal tearfilm composition and tear amount.
B.C.R. 6.00 – 10.50 per 0.05 ascending
Power +/-40.00 per 0.25 ascending
Thickness Tetra 0.20 at -3.00
Thickness Flexi 0.16 at -3.00
Lens diameter 8.00 – 12.50 per 0.10 ascending
Periphery radii can be specified as P1/P2.
P1 can be selected between 10 and 120 (0.10 mm to 1.20 mm flatter than the B.C.R.).
P2 can be chosen between 10 and 120 (0.10 mm to 1.20 mm flatter than P1).
K flat + or –
0 .00 > 0.50
0.75 > 1.25
1.50 > 2.00
2.25 > 2.50
2.75 > 3.00
– 0.10 of Randtoric
3.25 > 3.50
– 0.15 R.T or Exception
3.75 > 4.00
– 0.20 R.T or Exception
4.25 > 4.50
– 0.25 R.T or Exception
4.50 > 6.50
– 0.30 R.T or Exception
Choice of diamater
2 mm smaller than the vertical cornea diameter.
Do you have any questions and/or comments about this product? Please let us know!
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