Search

CN-122026216-A - Pulse laser driving circuit and method thereof

CN122026216ACN 122026216 ACN122026216 ACN 122026216ACN-122026216-A

Abstract

The invention relates to a pulse laser driving circuit and a method thereof, wherein the pulse laser driving circuit comprises a laser, an energy storage element, a controller, a first switching element and a second switching element; the other end of the energy storage element is electrically connected with the input end of the laser, the controlled end of the first switching element is electrically connected with the first control end, the input end of the first switching element is electrically connected with the other end of the energy storage element, the output end of the first switching element is grounded, the controlled end of the second switching element is electrically connected with the second control end, and the input end of the second switching element is electrically connected with the output end of the laser. According to the invention, the control of the charging time of the energy storage element and the control of the on time of the laser are independent through the energy storage element, the controller, the first switching element and the second switching element, and the establishment speed of the current rising edge and the width of the laser pulse can be respectively and independently and accurately regulated on the premise of not changing the switching frequency, so that the requirements on the rapid rising edge and the wide-range accurate pulse width can be met.

Inventors

  • LUO WEI
  • ZHU FANGSHUN
  • WANG CHUANQING

Assignees

  • 华中光电技术研究所(中国船舶集团有限公司第七一七研究所)

Dates

Publication Date
20260512
Application Date
20251224

Claims (10)

  1. 1. A pulsed laser driving circuit, comprising: A laser (1); an energy storage element (2), one end of the energy storage element (2) is used for being connected with a power supply (9), the other end of the energy storage element (2) is electrically connected with the input end of the laser (1), and the energy storage element (2) is configured to store and release energy; A controller (3) having a first control terminal and a second control terminal; A first switching element (4), a controlled end of the first switching element (4) is electrically connected with the first control end, an input end of the first switching element (4) is electrically connected with the other end of the energy storage element (2), an output end of the first switching element (4) is grounded, and the first switching element (4) is configured to perform on-off operation when receiving a first pulse width modulation signal from the first control end; And a second switching element (5), wherein a controlled end of the second switching element (5) is electrically connected with the second control end, an input end of the second switching element (5) is electrically connected with an output end of the laser (1), the output end of the second switching element (5) is grounded, and the second switching element (5) is configured to perform on-off operation when receiving a second pulse width modulation signal from the second control end.
  2. 2. The pulsed laser driving circuit according to claim 1, characterized by comprising a voltage controlled constant current source circuit (6), the controller (3) having a reference voltage terminal, a first input terminal of the voltage controlled constant current source circuit (6) being electrically connected to the reference voltage terminal, a second input terminal of the voltage controlled constant current source circuit (6) being electrically connected to the output terminal of the first switching element (4) and the output terminal of the second switching element (5), the output terminal of the voltage controlled constant current source circuit (6) being grounded, the voltage controlled constant current source circuit (6) being configured to receive a reference voltage adjustment operating voltage from the reference voltage terminal.
  3. 3. The pulsed laser driving circuit according to claim 2, characterized by comprising an over-current protection circuit (7), an input of the over-current protection circuit (7) being electrically connected with the other end of the energy storage element (2), an output of the over-current protection circuit (7) being electrically connected with the input of the laser (1), the over-current protection circuit (7) being configured to limit an input current of the laser (1).
  4. 4. A pulsed laser driving circuit according to claim 3, characterized in that the over-current protection circuit (7) comprises a current limiting resistor (71), one end of the current limiting resistor (71) being the input of the over-current protection circuit (7), the other end of the current limiting resistor (71) being the output of the over-current protection circuit (7).
  5. 5. The pulse laser driving circuit according to claim 4, wherein the overcurrent protection circuit (7) includes a first unidirectional conductive element (72), an input terminal of the first unidirectional conductive element (72) is electrically connected to the other end of the current limiting resistor (71), and an output terminal of the first unidirectional conductive element (72) serves as an output terminal of the overcurrent protection circuit (7).
  6. 6. The pulsed laser driving circuit according to claim 5, characterized in that it comprises a second unidirectional conducting element (8), the input of the second unidirectional conducting element (8) being for accessing a power source (9), the output of the second unidirectional conducting element (8) being electrically connected to the input of the laser (1).
  7. 7. The pulsed laser driving circuit according to claim 6, characterized in that the first unidirectional conducting element (72) and the second unidirectional conducting element (8) are diodes.
  8. 8. The pulsed laser driving circuit according to any one of claims 1 to 7, characterized in that the energy storage element (2) is an inductance.
  9. 9. The pulsed laser driving circuit according to any one of claims 2 to 7, characterized in that the first switching element (4), the second switching element (5) and the third switching element (63) are transistors, or the first switching element (4), the second switching element (5) and the third switching element (63) are power field effect transistors.
  10. 10. A pulsed laser driving method applied to the pulsed laser driving circuit according to any one of claims 1 to 7, characterized by comprising: In each driving cycle, the following timing control steps are performed: A charging stage, wherein a controller (3) controls the first switching element (4) to be on and the second switching element (5) to be off so as to enable a power supply (9) to charge the energy storage element (2) through the first switching element (4), and the current in the energy storage element (2) increases along with the time; A laser driving stage in which a controller (3) controls the first switching element (4) to be turned off and simultaneously controls the second switching element (5) to be turned on so as to release energy stored in the energy storage element (2) and form a driving current flowing through the laser (1); and a reset stage, wherein a controller (3) controls the first switching element (4) and the second switching element (5) to be turned off so as to reduce the driving current of the laser (1) to zero.

Description

Pulse laser driving circuit and method thereof Technical Field The invention relates to the technical field of laser driving, in particular to a pulse laser driving circuit and a method thereof. Background The output performance core of the pulse laser depends on the pulse current parameter of the driving module. The steepness of the current rising edge determines the starting speed of the laser pulse, for example, in laser radar application, nanosecond (ns) rising edge is needed to realize high-precision ranging, the flexibility of the pulse width determines the output time length of laser energy, for example, in medical laser, the pulse width needs to be adjusted within a wide range of 10 ns to 100 mu s to adapt to the treatment requirements of different tissues, and the stability of the output current amplitude directly determines the consistency of the laser energy, for example, in laser cutting, current fluctuation is required to be within +/-2% to ensure the accuracy and repeatability of incision. Currently, a common pulse laser driving mostly adopts a control scheme based on single-path Pulse Width Modulation (PWM). This type of solution has the following significant drawbacks: 1. the rising edge is constrained by the pulse width, which typically requires a relatively large amount of energy to be applied across the laser when it is on in order to obtain a steep current rising edge. Under the condition of current pulse width change, the current waveform can have the conditions of overshoot, collapse and the like, the control accuracy of the pulse width is reduced, the output power is fluctuated, and even the laser is damaged and the like. It is difficult to meet the requirements for strictly adjustable pulse width in precision machining or measurement scenarios. 2. The output amplitude is unstable, namely, the single-path pulse width modulation drive often generates peak-type current pulses, the peak power of the current pulses is easily influenced by power supply fluctuation, load change and component parameter drift, obvious peak and fluctuation exist in the laser output power, the amplitude stability is poor, and the consistency and reliability of the laser processing effect are influenced. Disclosure of Invention Based on the above expression, the invention provides a pulse laser driving circuit and a method thereof, which aim to solve the problems of mutual restriction of rising edge and pulse width adjustment and unstable output amplitude of the existing pulse laser driving circuit. The technical scheme for solving the technical problems is as follows: In a first aspect, the present invention provides a pulsed laser driving circuit comprising: A laser; the laser comprises an energy storage element, a laser body and a control device, wherein one end of the energy storage element is used for being connected with a power supply, the other end of the energy storage element is electrically connected with the input end of the laser, and the energy storage element is configured to store and release energy; the controller is provided with a first control end and a second control end; A first switching element having a controlled end electrically connected to the first control end, an input end electrically connected to the other end of the energy storage element, an output end grounded, the first switching element configured to perform an on-off operation upon receiving a first pulse width modulation signal from the first control end; And a second switching element, a controlled end of which is electrically connected to the second control end, an input end of which is electrically connected to an output end of the laser, and an output end of which is grounded, the second switching element being configured to perform an on-off operation upon receiving a second pulse width modulation signal from the second control end. On the basis of the technical scheme, the invention can be improved as follows. Further, the controller comprises a voltage-controlled constant current source circuit, wherein the controller is provided with a reference voltage end, a first input end of the voltage-controlled constant current source circuit is electrically connected with the reference voltage end, a second input end of the voltage-controlled constant current source circuit is electrically connected with the output end of the first switching element and the output end of the second switching element, the output end of the voltage-controlled constant current source circuit is grounded, and the voltage-controlled constant current source circuit is configured to receive the reference voltage adjustment working voltage from the reference voltage end. Further, the laser comprises an overcurrent protection circuit, wherein the input end of the overcurrent protection circuit is electrically connected with the other end of the energy storage element, the output end of the overcurrent protection circuit is electrically connected with