▁a ▁computer - control led ▁light ▁mod ulator ▁to ▁a ▁single - p ixel ▁det ector . ▁ ▁App lications ▁ ▁B essel ▁beam ▁ill um ination ▁ ▁, ▁A RL ▁scient ists ▁developed ▁a ▁diff raction - free ▁light ▁beam , ▁also ▁called ▁B essel ▁beam ▁ill um ination . ▁In ▁a ▁paper ▁published ▁February ▁ 1 0 , ▁ 2 0 1 2 , ▁the ▁team ▁out lined ▁their ▁feas ibility ▁study ▁of ▁virtual ▁g host ▁imag ing ▁using ▁the ▁B essel ▁beam , ▁ ▁to ▁address ▁ad verse ▁conditions ▁with ▁limited ▁visibility , ▁such ▁as ▁cloud y ▁water , ▁j ung le ▁fol i age , ▁or ▁around ▁corners . ▁B essel ▁be ams ▁produce ▁concent ric - circle ▁patterns . ▁When ▁the ▁beam ▁is ▁blocked ▁or ▁obsc ured ▁along ▁its ▁traject ory , ▁the ▁original ▁pattern ▁eventually ▁re forms ▁to ▁create ▁a ▁clear ▁picture . ▁ ▁Im aging ▁with ▁very ▁low ▁light ▁levels ▁The ▁sp ont aneous ▁paramet ric ▁down - con version ▁( SP DC ) ▁process ▁provides ▁a ▁convenient ▁source ▁of ▁ent ang led - ph ot on ▁pairs ▁with ▁strong ▁spatial ▁correl ations . ▁Such ▁her ald ed ▁single ▁phot ons ▁can ▁be ▁used ▁to ▁achieve ▁a ▁high ▁signal - to - no ise ▁ratio , ▁virt ually ▁elimin ating ▁background ▁counts ▁from ▁the ▁recorded ▁images . ▁ ▁By ▁applying ▁principles ▁of ▁image ▁compression ▁and ▁associated ▁image ▁reconst ruction , ▁high - quality ▁images ▁of ▁objects ▁can ▁be ▁formed ▁from ▁raw ▁data ▁with ▁an ▁average ▁of