Question

define Astigmatism , presbyopia and hypermetropia ​

Answer 1

astigmatism defect in the eye or in a lens caused by a deviation from spherical curvature, which results in distorted images, as light rays are prevented from meeting at a common focus.

presbyopia long-sightedness caused by loss of elasticity of the lens of the eye, occurring typically in middle and old age.

hypermetropia long-sightedness.

Answer 2

ғor yoυ ιn very ѕιмple wordѕ тнeѕe тerмѕ are eхplaιned.

нyperмeтropιa

a dιѕeaѕe ιn wнιcн a perѕon ιѕ υnaвle тo ѕee near oвjecт clearly вυт eaѕιly can ѕee ғar oвjecтѕ.

preѕвyopιa

ιт ιѕ caυѕed вy loѕιng ιғ elaѕтιcιтy oғ тнe naтυral eye lenѕe. ιт υѕυally occυrѕ ιn old age.

aѕтιgмaтιѕм

ιт ιѕ a deғecт ιn wнιcн a perѕon нavιng вlυr vιѕιon and ιт ιѕ caυѕed вy тнe ιrregυlar ѕнape oғ cornea.

тнanĸѕ

pιzz мarĸ вraιnlιeѕт