▁market ▁with ▁their ▁first ▁devices . ▁ ▁F ove ated ▁rendering ▁is ▁a ▁new ▁technique ▁to ▁reduce ▁the ▁rendering ▁work load . ▁It ▁uses ▁eye ▁tracking ▁hardware ▁to ▁determine ▁at ▁what ▁point ▁the ▁user ▁is ▁looking ▁and ▁reduces ▁rendering ▁resolution ▁farther ▁from ▁the ▁user ' s ▁gaz e . ▁This ▁can ▁be ▁un not ice able ▁to ▁the ▁user ▁because ▁human ▁peri pher al ▁vision ▁is ▁far ▁less ▁sensitive ▁than ▁the ▁f ove a . ▁ ▁Resol ution ▁and ▁display ▁quality ▁ ▁There ▁are ▁different ▁opt ics ▁and ▁visual ▁qual ities ▁that ▁will ▁affect ▁how ▁the ▁individual ▁perce ives ▁the ▁image ▁quality ▁and ▁how ▁they ▁experience ▁the ▁virtual ▁world . ▁The ▁image ▁clar ity ▁depends ▁on ▁the ▁display ▁resolution , ▁opt ic ▁quality , ▁refresh ▁rate , ▁and ▁the ▁field ▁of ▁view . ▁ ▁Because ▁virtual ▁reality ▁head sets ▁stretch ▁a ▁single ▁display ▁across ▁a ▁wide ▁field ▁of ▁view ▁( up ▁to ▁ 1 1 0 ° ▁for ▁some ▁devices ▁according ▁to ▁manufact ur ers ), ▁the ▁magn ification ▁factor ▁makes ▁fla ws ▁in ▁display ▁technology ▁much ▁more ▁apparent . ▁One ▁issue ▁is ▁the ▁so - called ▁screen - door ▁effect , ▁where ▁the ▁g aps ▁between ▁rows ▁and ▁columns ▁of ▁pixels ▁become ▁visible , ▁kind ▁of ▁like ▁looking ▁through ▁a ▁screen ▁door . ▁This ▁was ▁especially ▁notice able ▁in ▁earlier ▁pro tot ypes ▁and ▁development ▁k its , ▁which ▁had ▁lower ▁resolution s ▁than ▁the ▁ret ail ▁versions . ▁ ▁L enses ▁▁ ▁The ▁l enses ▁of ▁the ▁head set ▁are ▁responsible