A laser driving apparatus comprising: a driver, comprising: a laser driving circuit, configured to generate a driving current (Idrive) to drive a laser; a tracking circuit, comprising: a reference current source, configured to generate a reference current (Iref) as a reference for the laser driving apparatus; and a replica circuit, having circuit architecture that is the same as at least a portion of the laser driving circuit, and configured to generate a sensing current (Isense) according to the reference current (Iref); a comparator, electrically coupled to the laser driving circuit and the replica circuit, configured to compare a first voltage (Vsig) measured at an output of the laser driving circuit and a second voltage (Vsen) measured at an output of the replica circuit to generate a comparison signal (Vcm); characterized in that: the laser driving apparatus further comprises: a control circuit, configured to receive the comparison signal (Vcm) and generate at least a first adjusting signal and a second adjusting signal according to the comparison signal (Vcm) and a mode signal (MODE), whereby the mode signal (MODE) is configured to control the control circuit to operate in at least a detection mode and a calibration mode, and wherein the tracking circuit further comprises: at least one first transistor, positioned on a current path of the replica circuit, configured to perform current adjustment, wherein, when the control circuit is controlled to operate in the detection mode according to the mode signal (MODE), the control circuit is configured to control the at least one first transistor via the first adjusting signal so as to adjust the sensing current (Isense), and wherein the laser driving circuit further comprises: at least one second transistor, positioned on a current path of the laser driving circuit, configured to perform current adjustment, wherein, when the control circuit is controlled to operate in the calibration mode according to the mode signal (MODE), the control circuit is configured to control the at least one second transistor via the second adjusting signal so as to adjust the driving current (Idrive). a driver, comprising: a laser driving circuit, configured to generate a driving current (Idrive) to drive a laser; a tracking circuit, comprising: a reference current source, configured to generate a reference current (Iref) as a reference for the laser driving apparatus; and a replica circuit, having circuit architecture that is the same as at least a portion of the laser driving circuit, and configured to generate a sensing current (Isense) according to the reference current (Iref); a reference current source, configured to generate a reference current (Iref) as a reference for the laser driving apparatus; and a replica circuit, having circuit architecture that is the same as at least a portion of the laser driving circuit, and configured to generate a sensing current (Isense) according to the reference current (Iref); a comparator, electrically coupled to the laser driving circuit and the replica circuit, configured to compare a first voltage (Vsig) measured at an output of the laser driving circuit and a second voltage (Vsen) measured at an output of the replica circuit to generate a comparison signal (Vcm); characterized in that: the laser driving apparatus further comprises: a control circuit, configured to receive the comparison signal (Vcm) and generate at least a first adjusting signal and a second adjusting signal according to the comparison signal (Vcm) and a mode signal (MODE), whereby the mode signal (MODE) is configured to control the control circuit to operate in at least a detection mode and a calibration mode, and wherein the tracking circuit further comprises: at least one first transistor, positioned on a current path of the replica circuit, configured to perform current adjustment, wherein, when the control circuit is controlled to operate in the detection mode according to the mode signal (MODE), the control circuit is configured to control the at least one first transistor via the first adjusting signal so as to adjust the sensing current (Isense), and at least one first transistor, positioned on a current path of the replica circuit, configured to perform current adjustment, wherein, when the control circuit is controlled to operate in the detection mode according to the mode signal (MODE), the control circuit is configured to control the at least one first transistor via the first adjusting signal so as to adjust the sensing current (Isense), and wherein the laser driving circuit further comprises: at least one second transistor, positioned on a current path of the laser driving circuit, configured to perform current adjustment, wherein, when the control circuit is controlled to operate in the calibration mode according to the mode signal (MODE), the control circuit is configured to control the at least one second transistor via the second adjusting signal so as to adjust the driving current (Idrive). at least one second transistor, positioned on a current path of the laser driving circuit, configured to perform current adjustment, wherein, when the control circuit is controlled to operate in the calibration mode according to the mode signal (MODE), the control circuit is configured to control the at least one second transistor via the second adjusting signal so as to adjust the driving current (Idrive).