Illinois Vision Certification Practice Test

Which three types of lenses are used in vision correction?

1. Convex, Concave, Planar

2. Concave, Convex, Cylindrical

3. Concave, Flat, Spherical

4. Convex, Biconcave, Biconvex

The correct answer is: Concave, Convex, Cylindrical

The correct answer focuses on the three primary types of lenses used in vision correction, which are concave, convex, and cylindrical. Concave lenses are used to correct nearsightedness (myopia) by diverging light rays and allowing them to focus further back on the retina. This helps individuals see distant objects more clearly. Convex lenses, on the other hand, are used for farsightedness (hyperopia) and work by converging light rays to bring the focus forward on the retina, aiding those who struggle with close-up tasks. Cylindrical lenses are specifically designed to correct astigmatism, where the curvature of the eye is not uniform in all meridians, leading to distorted or blurred vision. These lenses are shaped to address the particular axis of astigmatism, allowing for a clearer vision at all angles. The other answer options incorporate terms that either do not accurately describe common lens types used in vision correction or represent shapes not commonly associated with corrective lenses. For instance, planar lenses are not used as optical correction for vision, and the terms biconcave and biconvex while referring to specific lens shapes, are not commonly categorized in basic lens types for corrective purposes. Thus,