Photoelectric　synaptic　transistors　integrate　optical　sensing　and　synaptic　functions　into　a　single　device,　which　has　significant　advantages　in　neuromorphic　computing　for　visual　information,　recognition,　memory,　and　processing.　However,　the　weight　updating　of　existing　photoelectric　synapses　is　predominantly　based　on　separate　utilization　of　light　and　electrical　stimuli　to　regulate　synaptic　excitation　and　inhibition.　This　approach　significantly　restricts　the　processing　speed　and　application　scenarios　of　devices.　In　this　work,　we　propose　bipolar　synaptic　organic/inorganic　heterojunction　transistor　(BSOIHT)　that　can　effectively　simulate　bidirectional　(excitatory/inhibitory)　synaptic　behavior　under　light　stimulation.　Furthermore,　by　changing　the　position　of　electrode　contacts　and　the　metals　of　source　and　drain　electrodes,　carrier　injection　of　the　transistor　is　significantly　improved　with　reduced　synaptic　event　power　consumption　down　to　2.4　fJ.　Moreover,　the　BSOIHTs　are　adopted　to　build　the　neuromorphic　vision　system,　which　effectively　facilitates　image　preprocessing　and　substantially　enhances　the　recognition　accuracy　from　44.93%　to　87.01%.　This　paper　provides　new　avenues　for　the　construction　of　energy-efficient　artificial　vision　systems.　©　Science　China　Press　2024.