Light source system

A laser light source controller for coupling to a laser driver circuit that comprises a first transistor, a second transistor and a laser light source, wherein the laser light source controller is configured to:

• output a first control signal for controlling the first transistor;
• and
• output a second control signal to a second transistor that is coupled to the laser light source, wherein the first transistor, second transistor and laser light source are arranged in series such that when both the first transistor and second transistor are conducting, the laser light source turns on,
• wherein the laser light source controller is configured to control a pulse emission of light from the laser light source by:
• a) setting the first transistor, while the second transistor is in a non-conducting state, to a conducting state using the first control signal, the setting including pre-charging the first transistor by applying a turn-on voltage to a control terminal of the first transistor to charge a capacitance associated with the control terminal of the first transistor and removing the turn-on voltage applied to the control terminal of the first transistor such that the first transistor is held in an on-state by the capacitance associated with the control terminal of the first transistor;
• b) after setting the first transistor to the conducting state, turning on the laser light source by setting the second transistor to a conducting state using the second control signal such that both the first transistor and second transistor are conducting;
• and
• c) after setting the second transistor to the conducting state, turning off the laser light source by setting the first transistor to a non-conducting state.

A method for controlling a pulse of emission of light from a laser light source comprising:

• setting a first transistor coupled in series with the laser light source to a conducting state, the setting including pre-charging the first transistor by applying a turn-on voltage to a control terminal of the first transistor to charge a capacitance associated with the control terminal of the first transistor and removing the turn-on voltage applied to the control terminal of the first transistor such that the first transistor is held in an on-state by the capacitance associated with the control terminal of the first transistor, whilst a second transistor coupled in series with the laser light source is in a non-conducting state;
• turning on the laser light source by setting the second transistor to a conducting state such that both the first transistor and second transistor are conducting;
• and
• turning off laser light source by setting the first transistor to a non-conducting state.