Mindblown: a blog about philosophy.

Ventilated corneal trial lenses, each lens having a flat scleral rim 2 mm. wide, used to measure the cornea when fitting scleral contact lenses.  

A plastic corneal contact lens having its base curve parallel to the optic cup of the cornea and a secondary curve peripheral to the base curve and somewhat flatter; it may or may not have a bevel (peripheral curve) or other additional curves.  

A Galilean (terrestrial) telescopic system composed of a negative contact lens and a positive spectacle lens.  

A scleral contact lens which fits closely enough to the eye so that no auxiliary solution is necessary. The principle of fitting a scleral contact lens as close to the eye as possible so that the space between the lens and the eye will be filled with tear fluid, making use of an auxiliary solution…

A device employed for determining the base curve of a contact lens, with the aid of a keratometer or an ophthalmometer.  

A device employed for determining the base curve of a contact lens, with the aid of a keratomcter or an ophthalmometer. The lens is mounted horizontally so that its front surface is immersed in a layer of water or other fluid, and the mire image from the lens is viewed with the aid of a…

A method for finishing contact lens edges, involving the use of tools having differing radii of curvature and differing speeds of revolution.  

A contact lens designed so as to conform closely to the corneal surface.  

A bifocal contact lens having a round distance portion surrounded by an annular near portion, the distance portion being formed by a steeper curve in the central area of the front surface.  

A bifocal contact lens having a round distance portion surrounded by an annular near portion, the distance portion being formed by a steeper curve in the central area of the back surface.