00569nam a22001337a 4500020002400000082001500024100001700039245004900056260003000105300004200135490001500177500002000192650022300212  a9788131249154 (pbk)  a617.7bKHU  aKhurana, A K  aTheory and practice of optics and refraction  aNew DelhibElsevierc2018  aviii, 526 p.b: ill. (col.)c; 23 cm.  aMSO Series  aIncludes index.  aOptics-RefractionaRehabilitation sciences vOptonutry-OrthopticsvCorneal topographyvPhysiological opticsvOptical instrumentsvContrast sensitivityvRefractive surgeryvVisual acuityvSpectacles vOptometryvRCR&AHS