A　cholesteric　liquid　crystal　(CLC)　reflective　display　is　a　device　that　employs　CLC　to　reflect　external　ambient　light,　thereby　facilitating　the　transfer　of　information.　However,　traditional　CLC　reflective　displays　exhibit　a　relatively　slow　response　speed　and　are　unable　to　be　displayed　in　dark　environments.　Quantum　dots　(QDs),　which　are　nanoparticles　with　excellent　luminescence　performance,　can　be　doped　to　enhance　device　performance　and　the　display　effect.　This　paper　proposes　a　multimode　reflective　display　device　(MRDE)　that　can　respond　rapidly　to　temperature　and　low-frequency　AC　voltage,　and　can　realise　four　modes　of　display:　reflective　mode,　transmissive　mode,　scattering　mode　and　fluorescent　mode.　These　modes　can　be　converted　to　enhance　the　display　effect　and　expand　the　device＇s　application　range　in　diverse　scenarios.　In　reflective　mode,　MRDE　is　capable　of　shifting　between　reflective,　scattering　mode　and　transmissive　modes　in　response　to　changes　in　temperature　and　voltage,　and　of　encrypting　and　decrypting　information.　In　fluorescent　mode,　the　device　is　capable　of　displaying　in　dim　environments,　and　the　emission　wavelength　can　be　red-shifted　from　628　nm　to　636　nm　within　the　temperature　range　of　248　K　to　373　K.　Additionally,　it　can　provide　an　early　warning　for　low　and　high　temperature　environments.　The　device　is　capable　of　providing　early　warning　and　encryption　of　information　in　low　and　high　temperature　environments.　This　provides　a　theoretical　basis　and　guidance　for　the　preparation　of　new　devices　with　improved　display　performance,　multifunctional　integration,　and　temperature-responsive　information　encryption.　©　2025　SPIE.