trifocal


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tri·fo·cal

(trī'fō-kăl),
Having three foci. See: trifocal lens.

trifocal

/tri·fo·cal/ (tri-fo´-) (tri´fo-k'l)
1. having three foci.
2. containing one part for near vision, one for intermediate, and a third for distant vision, as a trifocal lens.

trifocal

(trī-fō′kəl, trī′fō′-)
adj.
1. Having three focal lengths.
2. Having one section that corrects for distant vision, a second section that corrects for medium vision, and a third that corrects for near vision, as an eyeglass lens.
n.
1. A lens having three focal lengths.
2. trifocals Eyeglasses having trifocal lenses.

trifocal

1. Having three focal lengths.
2. Distance-viewing spectacles having additional segments for intermediate and close ranges.
References in periodicals archive ?
Through this partnership, Alphaeon is able to bring PhysIOL trifocal lens technology to the United States for the first time.
This unique partnership enables ALPHAEON to bring PhysIOL Trifocal lens technology to the US for the first time, providing significant benefits to patients and physicians alike.
The DD14 28 trifocal is classed as an occupational double D segment, where the D segments are 14mm apart.
Last summer, Trevor's wife Carol spotted the London Eye Hospital offered the trifocal lens as a step forward from multifocal lenses, which have been in use for more than a decade but can result in poor intermediate vision and glare at nights.
Consultant ophthalmic surgeon Bobby Qureshi, who uses the new trifocal implant at the London Eye Hospital, says the results are almost instantaneous.
Augustine Good Physician: A College of South Trifocal Africa Perspective on Medicine as a Moral Enterprise 0128 S.
That ensures that, while aiming, I am looking through the main lens of my glasses, not the trifocal line.
Rimm's (2003) trifocal method for addressing underachievement, with collaboration between teachers and parents, has some empirical support.
A few examples of identities without this trifocal integration of behaviour, cognition, and affect include a male who develops a "crush" on another male (affect) but suppresses or represses sexual thoughts and fantasies about him (cognition).
Cherello says the technology has been around for 20 years, but only in the last five has it really taken off, especially with "progressive lenses," which are exploding in popularity for their ability to offer trifocal vision without the jarring effect of going directly from one lens to another.
Special bifocal or trifocal prescriptions can accommodate this unusual distance.
Positioning the evangelistic-missionary challenge near the "moral witness" foci, the shape of the resultant ecumenical conversation will be drawn as trifocal ellipsoid rather than the more common bifocal ellipse.