Intelligent　display　with　multifunctional　integration　is　becoming　the　frontier　and　focus　of　current　research　on　novel　display　technology.　How　to　realize　the　single　chip　integration　of　lighting　with　other　functions　such　as　switching　and　driving　remain　the　technical　and　scientific　problems　that　are　desiderated　to　solve.　This　article　proposes　a　novel　idea　of　a　light-emitting　triode　(LET),　in　which　light-emitting　diode　(LED)　and　bipolar　junction　transistor　(BJT)　are　vertically　integrated　on　a　single　GaN　chip　with　the　same　GaN　processing.　The　photoelectrical　performances　of　this　＂LED　on　BJT＂　structure　are　investigated　using　finite　element　simulation.　It　is　verified　that　LET　with　electrical-optical　modulation　and　amplification　capabilities　could　be　achieved　simultaneously.　By　optimizing　the　device　structure　and　the　doping　concentrations　of　each　epitaxial　layers,　the　LET　can　be　operated　at　a　low　modulation　current　injection　in　the　range　of　tens　of　microamperes.　Therefore,　the　LET　is　expected　to　be　directly　driven　by　IC　circuits　without　additional　amplifier　circuits.　Meanwhile,　the　LET　cut-off　frequency　can　reach　more　than　80　MHz,　allowing　the　applications　of　pulse　width　modulation　(PWM)　driving　and　visible　light　communications.