Double-perovskite-type　near-infrared　(NIR)　phosphors　have　emerged　as　a　desirable　research　hotspot,　benefiting　from　the　B/B＇O6　coordinations　suitable　for　Cr3+　luminescence.　However,　NIR　efficiency　and　thermostability　maintain　challenging.　Meanwhile,　the　precise　identification　of　the　Cr3+　occupancy　appears　to　be　particularly　important　due　to　the　abundant　cation　sites　in　double-perovskite　structure.　Herein,　this　research　reported　a　Cr3+activated　A2BB＇O6　(Ca2AlTaO6)　NIR　phosphor　with　high　luminescence　heat-resistance　(94　%@423　K).　Under　444　nm　excitation,　Ca2AlTaO6:1.2　%Cr3+　exhibits　sharp　emission　originating　from　the　2Eg　-＞　4A2　transition　of　Cr3+.　The　visualized　proof　provided　by　aberration-corrected　transmission　electron　microscopy　and　spectral　analysis　confirm　that　Cr3+　simultaneously　occupies　[BO6]　and　[B＇O6]　sites.　Moreover,　the　B　site　regulation　by　Ga3+　boosts　luminescent　efficiency　1.5　times.　The　Ca2Al0.8Ga0.2TaO6:1.2　%Cr3+-converted　NIR　LED　device　demonstrates　stable　photoelectric　performance　under　high　current　over　an　extended　period.　Subsequently,　the　fascinating　material　is　successfully　demonstrated　via　the　multifunctional　applications　in　non-destructive　detection,　night　vision,　and　plant　growth　lighting.　This　work　provides　valuable　insights　for　constructing　better　doubleperovskite-type　NIR-emitting　materials.