CN103474873A - Narrow-pulse-width high-power semiconductor laser device driving circuit - Google Patents

Abstract

The invention discloses a high-power semiconductor laser drive circuit with narrow pulse width. The semiconductor laser drive circuit includes a pulse control circuit, a drive circuit, a high-voltage terminal, a low-voltage terminal, a TTL signal terminal and a ground terminal, wherein the pulse control circuit is simultaneously connected to As for the drive circuit, the low voltage terminal, the TTL signal terminal and the ground terminal, the drive circuit is simultaneously connected to the high voltage terminal, the pulse control circuit and the ground terminal. The invention can realize the adjustable pulse light signal with rising edge 5ns, pulse width 11ns, repetition frequency 1Hz-50KHz, and can provide relatively large driving current at the same time.

Description

A Narrow Pulse Width High Power Semiconductor Laser Driving Circuit

technical field

The invention relates to a driving circuit applied to a high-power semiconductor laser with a narrow pulse width. The narrow pulse width driving circuit can realize pulse output with an optical signal pulse width of 11 ns and a rising edge of 5 ns, and the repetition frequency can be adjusted from 1 Hz to 50 KHz.

Background technique

With the development of semiconductor lasers, pulsed semiconductor lasers with high repetition rate, fast front, narrow pulse width and high peak power have been widely used in industry, military, scientific research and other fields, such as laser ranging, laser radar, laser communication, pump Pu solid-state laser, pulse Doppler imaging, 3D image system and fiber optic temperature sensor, etc. However, in order to obtain a high-energy, narrow pulse width optical pulse, a high-power semiconductor laser needs a seed light source that can provide a good optical pulse. It not only requires the output optical pulse to have a high repetition rate, a fast rising edge, and a narrow Pulse width, pulse current with a certain amplitude, and the waveform of the output optical pulse must be smooth, and the power and center wavelength of the laser output must be stable. High peak power, narrow pulse width, and fast rising edge can improve the resolution of relevant sensors and increase the laser range.

For example, in a distributed optical fiber temperature measurement system based on Raman scattering, the Raman scattered light carrying temperature information is weak, and it is necessary to increase the optical power of the laser to improve the signal-to-noise ratio, thereby improving the temperature resolution. The system uses fiber-optic time-domain reflectometers to measure distance, and its distance resolution improves as the optical pulse width decreases. In the laser short-distance detection system, the steeper the laser pulse frontier, the better, because it directly affects the dynamic test accuracy of the laser detection system. The steeper the frontier, the higher the ranging accuracy. In laser detection and laser communication, system bandwidth, operating distance, accuracy, anti-interference and low power consumption all depend on the quality of the pulse emitted by the semiconductor laser. In pulsed semiconductor laser range finders and laser radars, the rise time and It is related to the measurement accuracy. The shorter the rise time, the better the measurement accuracy. The peak power of the pulsed laser is closely related to the distance measurement capability. The greater the power, the stronger the distance measurement capability. The laser pulse width is related to the signal-to-noise ratio of the received signal. The narrower, the higher the signal-to-noise ratio.

The main factor affecting the quality of laser pulses is the performance of the drive power supply. Foreign countries have invested heavily in laser drive research, and many drives have been modularized and run stably and reliably. In contrast, there is little research in this area in China. In China, most semiconductor laser drive power supplies are still DC or low-frequency pulses, and there are almost no finished products for high-current narrow-pulse drive power supplies. Therefore, the development of a semiconductor laser drive circuit with a narrow pulse width is of great significance.

Contents of the invention

(1) Technical problems to be solved

The purpose of the present invention is to provide a driving circuit applied to high-power semiconductor lasers with narrow pulse width, which can realize pulsed optical signals with adjustable rising edge of 5ns, pulse width of 11ns, and repetition frequency of 1Hz-50KHz, and can provide larger drive current.

(2) Technical solutions

In order to achieve the above object, the present invention provides a high-power semiconductor laser drive circuit with a narrow pulse width, the semiconductor laser drive circuit includes a pulse control circuit, a drive circuit, a high voltage terminal, a low voltage terminal, a TTL signal terminal and a ground terminal, wherein, The pulse control circuit is simultaneously connected to the drive circuit, the low voltage terminal, the TTL signal terminal and the ground terminal, and the drive circuit is simultaneously connected to the high voltage terminal, the pulse control circuit and the ground terminal.

In the above solution, the pulse control circuit includes a first resistor R1, a first capacitor C1, a second resistor R2, a first diode PD1 and a first switch MOSFET-1, wherein: one end of the first resistor R1 is connected to the TTL signal The other end is connected to one end of the first capacitor C1; the other end of the first capacitor C1 is connected to the second resistor R2, the first diode PD1 and the first switch MOSFET-1 at the same time; the other end of the second resistor R2 They are respectively connected in parallel with the ground terminal and the other end of the first diode PD1; one end of the first switching tube MOSFET-1 is connected to the low voltage terminal, one end is connected to the ground terminal, and the other end is connected to one end of the second switching tube MOSFET-2.

In the above scheme, the first switching tube MOSFET-1 is a high-speed field effect transistor, and the on and off of the first switching tube MOSFET-1 is controlled through the TTL signal terminal and the first diode PD1; by adjusting the first switching tube MOSFET-1 A resistor R1, a second resistor R2 and a first capacitor C1 are used to control the electrical pulse width inside the semiconductor laser drive circuit.

In the above scheme, the low-voltage terminal supplies power to the first switching tube MOSFET-1, and the voltage value is controlled at 12-15V; the TTL signal terminal is a TTL pulse signal with a voltage value of 3.3-5V and a 50% duty cycle; the semiconductor laser drives The frequency of the circuit is 1Hz-50KHz, controlled by the TTL signal terminal.

In the above solution, the drive circuit includes a second switching tube MOSFET-2, a third resistor R3, a second capacitor C2, a second diode PD2, a laser, a fourth resistor R4, and a third capacitor C3, wherein: the second One end of the switching tube MOSFET-2 is connected to the third resistor R3 and the second capacitor C2 at the same time, and the other end is respectively connected to the ground terminal, the second diode PD2, the laser and the third capacitor C3 at the same time; the other end of the third resistor R3 is connected to The high voltage end is connected; the other end of the second capacitor C2 is simultaneously connected to the second diode PD2, the laser and the fourth resistor R4; the other end of the fourth resistor R4 is connected to the other end of the third capacitor C3.

In the above scheme, the second switching tube MOSFET-2 is a high-speed field effect transistor, and the electric pulse signal provided by the pulse control circuit controls the switch of the second switching tube MOSFET-2; Charge the second energy storage capacitor C2; discharge the second energy storage capacitor C2 to power up the laser to generate optical signals; the charging and discharging time of the second energy storage capacitor C2 is controlled by the second switching tube MOSFET-2; the second diode PD2 It is a reverse diode to protect the laser; the fourth resistor R4 and the third capacitor C3 are used to absorb the signal oscillation after the falling edge of the pulse signal to obtain a better pulse waveform.

In the above solution, the high-voltage end supplies power to the laser, and its voltage value matches the withstand voltage value of the second energy storage capacitor C2 and the second switching tube MOSFET-2. The voltage value is 1-200V.

(3) Beneficial effects

As can be seen from the foregoing technical solutions, the present invention has the following beneficial effects:

1. Utilizing the present invention, since the high-speed pulse control structure is used inside the drive circuit to realize the control of the pulse drive circuit, the selected switch tube is used in conjunction with its corresponding device, and the response speed is very fast. By optimizing the selected device parameters , can realize narrow pulse signal with adjustable rising edge of 5ns, pulse width of 11ns, and repetition frequency of 1Hz-50KHz, and can provide a large driving current at the same time. In addition, the driving circuit has a simple structure and can be made into an ultra-small circuit board for use in an ultra-small pulse device structure.

Description of drawings

The structure, characteristics and technical content of the present invention are further described below by referring to the detailed description of the specific embodiments in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic structural diagram of a high-power semiconductor laser drive circuit with a narrow pulse width provided by the present invention.

FIG. 2 is a diagram of the measured optical pulse signal in the working state of the driving circuit of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

Please refer to shown in Fig. 1, Fig. 1 is the structural representation of the high-power semiconductor laser driving circuit of narrow pulse width that the present invention provides, and this semiconductor laser driving circuit comprises pulse control circuit, driving circuit, high voltage end, low voltage end, TTL signal end and the ground terminal, wherein the pulse control circuit is simultaneously connected to the drive circuit, the low voltage terminal, the TTL signal terminal and the ground terminal, and the drive circuit is simultaneously connected to the high voltage terminal, the pulse control circuit and the ground terminal.

Wherein, the pulse control circuit includes a first resistor R1, a first capacitor C1, a second resistor R2, a first diode PD1 and a first switch MOSFET-1, wherein: one end of the first resistor R1 is connected to the TTL signal end, and the other One end is connected to one end of the first capacitor C1; the other end of the first capacitor C1 is connected to the second resistor R2, the first diode PD1 and the first switching tube MOSFET-1 at the same time; the other end of the second capacitor R2 is connected to the ground respectively One end of the first switch tube MOSFET-1 is connected in parallel with the other end of the first diode PD1; one end of the first switch tube MOSFET-1 is connected to the low voltage terminal, one end is connected to the ground terminal, and the other end is connected to one end of the second switch tube MOSFET-2. The first switching tube MOSFET-1 is a high-speed field effect transistor, which controls the on and off of the first switching tube MOSFET-1 through the TTL signal terminal and the first diode PD1; by adjusting the first resistor R1, the second The resistor R2 and the first capacitor C1 are used to control the electrical pulse width inside the semiconductor laser drive circuit. The low-voltage terminal supplies power to the first switching tube MOSFET-1, and the voltage value is controlled at 12-15V; the TTL signal terminal is a TTL pulse signal with a voltage value of 3.3-5V and a 50% duty cycle; the frequency of the semiconductor laser drive circuit is 1Hz- 50KHz, controlled by TTL signal terminal.

The driving circuit includes a second switching tube MOSFET-2, a third resistor R3, a second capacitor C2, a second diode PD2, a laser, a fourth resistor R4 and a third capacitor C3, wherein: the second switching tube MOSFET-2 One end is connected to the third resistor R3 and the second capacitor C2 at the same time, and the other end is connected to the ground terminal, the second diode PD2, the laser and the third capacitor C3 at the same time; the other end of the third resistor R3 is connected to the high voltage end; the second The other end of the capacitor C2 is simultaneously connected to the second diode PD2, the laser and the fourth resistor R4; the other end of the fourth resistor R4 is connected to the other end of the third capacitor C3. The second switching tube MOSFET-2 is a high-speed field effect transistor, and the electric pulse signal provided by the pulse control circuit controls the switch of the second switching tube MOSFET-2; the high-voltage terminal supplies energy to the second capacitor C2 by protecting the third resistor R3 Charging; the second energy storage capacitor C2 is discharged to power the laser to generate an optical signal; the charging and discharging time of the second energy storage capacitor C2 is controlled by the second switching tube MOSFET-2; the second diode PD2 is a reverse diode, for The laser is protected; the fourth resistor R4 and the third capacitor C3 are used to absorb the signal oscillation after the falling edge of the pulse signal to obtain a better pulse waveform. The high-voltage end supplies power to the laser, and its voltage value matches the withstand voltage value of the second energy storage capacitor C2 and the second switching tube MOSFET-2, and the voltage value is generally 1-200V.

To sum up, since the drive circuit uses a high-speed pulse control structure to realize the control of the pulse drive circuit, and the selected switching tube is used in conjunction with its corresponding device, the response speed is very fast. By optimizing the parameters of the selected device to achieve Narrow pulse width and high current output, so the driving circuit of the narrow pulse width high-power semiconductor laser provided by the present invention can realize pulsed optical signals with a rising edge of 5ns, a pulse width of 11ns, and a repetition frequency of 1Hz-50KHz. The measured optical pulse signal diagram is shown in Figure 2. At the same time, it can provide a larger driving current.

The specific embodiments described above have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above descriptions are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (8)

1. the high power semiconductor lasers drive circuit of a narrow pulsewidth, it is characterized in that, this semiconductor laser device driving circuit comprises pulse control circuit, drive circuit, high-pressure side, low-pressure end, TTL signal end and earth terminal, wherein, pulse control circuit is connected in drive circuit, low-pressure end, TTL signal end and earth terminal simultaneously, and drive circuit is connected in high-pressure side, pulse control circuit and earth terminal simultaneously.

2. the high power semiconductor lasers drive circuit of narrow pulsewidth according to claim 1, it is characterized in that, described pulse control circuit comprises the first resistance (R1), the first electric capacity (C1), the second resistance (R2), the first diode (PD1) and the first switching tube (MOSFET-1), wherein:

The first resistance (R1) end is connected with the TTL signal end, and the other end is connected with an end of the first electric capacity (C1); The other end of the first electric capacity (C1) is connected in the second resistance (R2), the first diode (PD1) and the first switching tube (MOSFET-1) simultaneously;

The second resistance (R2) other end is respectively with earth terminal and the first diode (PD1) other end and connect;

The first switching tube (MOSFET-1) end is connected with low-pressure end, and an end is connected with earth terminal, and the other end is connected with second switch pipe (MOSFET-2) end.

3. the high power semiconductor lasers drive circuit of narrow pulsewidth according to claim 2, it is characterized in that, described the first switching tube (MOSFET-1) is high-speed field effect transistors, controls the turn-on and turn-off of this first switching tube (MOSFET-1) by TTL signal end and the first diode (PD1); Control the electronic pulse width of this semiconductor laser device driving circuit inside by regulating the first resistance (R1), the second resistance (R2) and the first electric capacity (C1).

4. the high power semiconductor lasers drive circuit of narrow pulsewidth according to claim 3, is characterized in that, described low-pressure end is given the first switching tube (MOSFET-1) power supply, and magnitude of voltage is controlled at 12-15V; The TTL pulse signal that the TTL signal end is magnitude of voltage 3.3-5V, 50% duty ratio; The frequency of this semiconductor laser device driving circuit is 1Hz-50KHz, by the TTL signal end, is controlled.

5. the high power semiconductor lasers drive circuit of narrow pulsewidth according to claim 1, it is characterized in that, described drive circuit comprises second switch pipe (MOSFET-2), the 3rd resistance (R3), the second electric capacity (C2), the second diode (PD2), laser, the 4th resistance (R4) and the 3rd electric capacity (C3), wherein:

One end of second switch pipe (MOSFET-2) is connected in the 3rd resistance (R3) and the second electric capacity (C2) simultaneously, and the other end is connected in respectively earth terminal, the second diode (PD2), laser and the 3rd electric capacity (C3) simultaneously; The 3rd resistance (R3) other end is connected with high-pressure side; The second electric capacity (C2) other end is connected in the second diode (PD2), laser and the 4th resistance (R4) simultaneously; The other end of the 4th resistance (R4) is connected with the other end of the 3rd electric capacity (C3).

6. the high power semiconductor lasers drive circuit of narrow pulsewidth according to claim 5, it is characterized in that, described second switch pipe (MOSFET-2) is high-speed field effect transistors, and the electric impulse signal provided by pulse control circuit is controlled the switch of this second switch pipe (MOSFET-2); Give energy storage the second electric capacity (C2) charging by high-pressure side by protection the 3rd resistance (R3); Power up the generation light signal by energy storage the second electric capacity (C2) electric discharge to laser; The time that discharges and recharges of energy storage the second electric capacity (C2) is controlled by second switch pipe (MOSFET-2); The second diode (PD2) is backward diode, and laser is protected; The 4th resistance (R4) and the 3rd electric capacity (C3), in order to absorb the signal oscillating after the pulse signal trailing edge, obtain better impulse waveform.

7. the high power semiconductor lasers drive circuit of narrow pulsewidth according to claim 6, it is characterized in that, described high-pressure side is powered to laser, and the withstand voltage of its magnitude of voltage and energy storage the second electric capacity (C2) and second switch pipe (MOSFET-2) is complementary.

8. the high power semiconductor lasers drive circuit of narrow pulsewidth according to claim 7, is characterized in that, described magnitude of voltage is 1-200V.

Images