Based in Cambridge, this office has developed various types of contact-lens technologies, including freeform surface modelling, toric lens design, and wavefront technologies, as well as lenses for persons suffering from keratoconus and corneal trauma.
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To avoid phantom indications the design makes use of a special inverted toric lens ( i . e . a single clear Fresnel lens mounted step sides outwards ) with a portion of the lens steps painted black.
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Some spherical rigid lenses can also correct for astigmatism . ( See below . ) Because a toric lens must have the proper orientation to correct for a person's astigmatism, such a CL must have additional design characteristics to prevent it from rotating away from the ideal alignment.
