Laser output control is mainly controlled by GATE signal; The specific frequency, power and other parameters of the output light are controlled by the PWM signal, mainly to change the frequency cycle and duty cycle in the PWM.
Duty cycle: that is, the ratio of the high level holding time to the PWM clock cycle time in the output PWM signal.
For example, if the frequency of a PWM is 50KHZ, its clock cycle is 20 μ s. If the time of high level is 6 μ s. Then the time of low level must be 14 μ s. Then the duty cycle is 6:20, that is, the duty cycle of PWM is 3:10.
At a certain frequency value, when the high level of the laser PWM signal is 1 us, the corresponding ADJUST=100%, which represents the maximum power, the minimum optical pulse width, and the maximum peak power at this frequency. When the high level pulse width is increased (i.e., the ADJUST value is reduced), the power of the flat laser decreases and the optical pulse width increases; The frequency, power and pulse width of the optical pulse can be controlled by the frequency and duty ratio of the PWM signal (the signal for Q drive).
1. GATE control mode
When the laser is under GATE mode control, it is only necessary to connect a BNC interface shield wire to the GATE interface, and the other end to the corresponding interface of the upper computer to realize laser control. At this time, the user cannot select QS-EXT mode, otherwise the laser will not emit light.
When the GATE signal interface is suspended or at low level, the laser can emit light, and other states are very weak indicator light; In this mode, the current, frequency and PWM (pulse width modulation) of the laser are provided inside the laser power control box, and the parameters can be changed on the front panel.
2. External TRIG control mode
When the laser is in the external TRIG control mode, the frequency and PWM (pulse width modulation) external control of the laser can be realized. At this time, the user needs to select the QS-EXT mode and connect the TRIG line and GATE line to the corresponding interface of the upper computer with the shielded wire with BNC connector. (Users are recommended to work in this mode)
Source: Network
