ABO Practical| Optician Practical Exam Study Material Questions and Answers

a lens focal length may be altered by? - changing the curvature of one surface what controls the amount of light that enters the eye? - Iris lights changing direction as it passes from one medium to another is called what? - refraction meniscus, equiconcave and flat concave are all, what? - minus lenses what term is used to describe the eyes tendency to TURN from its normal position? - phoria refractive condition where light focuses directly ON the retina...? - emmetriopia one convex and one concave surface is known as... - a meniscus lens best lens treatment to reduce water and road glare? - polarized establishes commercial and industry standards.. - ANSI hard resin used in plastic - cr39 multifocals are measured to the... - lower edge of lens not frame corneas index of refraction - 1.37 lens characteristic that corrects astigmatism is called.... - cylinder power progressive marks are ______ mm apart - 34 mm what prism could help EXOtropia? - base in prism what prism could help ESOtropia? - base out prism what happens if you move a PLUS lens CLOSER to the eye? - loses perceived power what happens if you move a PLUS lens AWAY from the eye? - gains perceived power what happens if you move a MINUS lens CLOSER to the eye? - gains perceived power what happens if you move a MINUS lens AWAY from the eye? - loses perceived power Vertical prism U&U and D&D cancel out, but U&D you ____ - ADD U and D horizontal prism O&O add, I&I add, But I&O____ - Cancel ea other I&O TP @ 90 first column is? - 0,30,45,60,90 light travels at.... - 186,000 mps both sides of lens is minus? - biconcave both sides of lens are plus? - biconvex plus lens decentered out will make the lens.... - thicker temporally minus lens decentered out will make the lens.... - thicker nasally ANSI standard on pd? - 2.5mm ANSI for vertical prism? - .33 ANSI for horizontal prism? - .67