Cov kws tshawb nrhiav tsim muaj ultra-ceev, rhiab heev avalanche photodiode (APD) uas tsim hluav taws xob" suab nrov" uas yog me dua li lwm cov khoom siv roj nplua nyeem.
APD yog ib tug semiconductor ntaus ntawv uas siv cov" photoelectric nyhuv" (Thaum lub teeb yog irradiated mus rau ib tug cov ntaub ntawv uas) thiab yog tshwj xeeb yog rhiab, muaj peev xwm hloov lub teeb rau hauv hluav taws xob. Kev ceev ceev, ntau dua cov APD xav tau thoob plaws ntiaj teb xav tau kev siv cov ntaub ntawv sib txuas lus nrawm nrawm thiab nrhiav kom tau lub teeb thiab thaj tsam (lidar) rau cov kev tsav tsheb ntawm tus kheej.