ABO (Practice Test)with complete solutions already graded A+

To what does a ptosis crutch give support? -Upper Lid. How is a lens' focal LENGTH altered? -Changing the curvature of one surface. Which instrument measures vertex distance? -Distometer. What controls the amount of light that enters the eye? -Iris. Which word is used to describe light's changing direction as it passes from one medium to another? -Refraction. Frame materials are available in which two forms? -Metal and plastic. Meniscus, equiconcave and flat concave are types of what? -Minus lenses. What term is used to describe the eye's TENDENCY to turn from it's normal position? -Phoria What is the refractive condition in which light focuses directly on the retina? -Emmetropia. What kind of lens has one convex and one concave surface? -Meniscus. What material has the most favorable OPTICAL properties? -Crown Glass. What is the best lens treatment to reduce water and road surface glare? -Polarized. Which private agency is responsible for establishing commercial and industry standards? -ANSI (Z80.1) Which frame adjustment lowers the front of the frame? -Spreading pads further apart. The hard resin material used in plastic lenses is known as? -CR-39. How is multifocal height usually measured? -From the lower edge of the lens. Aphakia is? -The absence of the crystalline lens. What is an advantage to a titanium frame? -Corrosion Resistant. What is the cornea's index of refraction? -1.37 Which term is used to describe the outward inclination of the bottom of a framed lens? -Retroscopic. Which lens characteristic corrects astigmatism? -Cylinder Power. A patient with astigmatism has a ___________cornea? -Misshapen. What is a polariscope used to detect? -Internal Lens Stress.