ABO Practice Test (Questions and Answers 100% correct)

ABO Practice Test (Questions and Answers 100% correct) When discussing thick lenses, the factors which are considered in computing the lens power are: a. front curve, thickness and index b. back curve, thickness and index c. front curve, back curve and thickness d. front curve, back curve, thickness and index - Answer ️️ -d. front curve, back curve, thickness and index Toric transposition shows: a. lens thickness b. power in principal meridians c. the power of the ADD d. the lens diameter - Answer ️️ -b. power in principal meridians Increasing the diameter of a minus power lens always increases its: a. vertex power b. center thickness c. weight d. refractive index - Answer ️️ -c. weight The optical center of a round segment is located: a. at the very top of the segment b. in the geometric center of the segment c. 5 mm from the top of the segment d. at the very bottom of the segment - Answer ️️ -b. in the geometric center of the segment The base curve of any multifocal lens is found on the surface containing the: a. cross curve b. cylinder surface c. segment d. ocular curve - Answer ️️ -c. segment Normal slab-off (bicentric grind) is ground on the lens whose vertical meridian has the: a. strongest curves b. most plus power c. least plus power d. least minus power - Answer ️️ -c. least plus power The refractive error indicated by the Rx +1.75 -2.75 x 090 is: a. compound hyperopic astigmatism b. compound myopic astigmatism c. simple myopic astigmatism d. mixed astigmatism - Answer ️️ -d. mixed astigmatism Tempering a lens by heat treating results in a lens being: a. less resistant to impact b. more resistant to impact c. more resistant to surface scratching d. impossible to break - Answer ️️ -b. more resistant to impact A slab-off lens is for the correction of: a. astigmatic errors b. excessive weight of lens c. excessive prism imbalance at the reading level d. exotropia - Answer ️️ -c. excessive prism imbalance at the reading level Chem-tempering makes a glass lens more impact resistant by placing the lens in a potassium nitrate bath. The lens undergoes a process known as: a. ion exchange b. iron oxide activation c. silver halide transfer d. thermal bleaching - Answer ️️ -a. ion exchange Which wavelengths of light h