Miniaturized all-solid-state laser and laser detection system

Abstract

The present disclosure provides a miniaturized all-solid-state laser and a laser detection system, which comprises: a shift signal generation module (1) for generating multiple shift square wave signals; a multiple pulse constant current driving module (2) for converting the multiple shift square wave signals into multiple constant pulse currents; a semiconductor laser array pumping module (3) for generating multiple pumping light signals according to the multiple constant pulse current driving mode; a laser bonding crystal (4) for converting the multiple pumping light signals into multiple laser pulse signals through a passive Q-switching mode; a micro detection array module (5) for monitoring the multiple laser pulse signals and generating multiple negative pulse electrical signals synchronized with the multiple laser pulse signals; an optical synchronization signal feedback module (6) for converting the multiple negative pulse electrical signals into negative pulse synchronization feedback signals and inputting the negative pulse synchronization feedback signals into the multiple pulse constant current driving module (2) to form a negative feedback network; and an optical distribution module (7) for changing the propagation direction of the multiple laser pulse signals.

Description

Technical Field

[0001] The present disclosure relates to the technical field of laser detection, and in particular to a miniaturized all-solid-state laser and a laser detection system. Background Art

[0002] Laser detection, a target detection method that emerged with the development of laser technology, is widely used in unmanned driving and terrain exploration due to its excellent resistance to electronic interference and ease of direction recognition. It is gaining increasing application and development in various fields. Anti-interference capability directly determines detection performance and is one of the most important indicators for evaluating laser detection system performance. Therefore, improving the anti-interference ability of detection systems has always been a key research issue.

[0003] The laser detection system mainly includes the emission system, receiving system and signal processing system. The emission system, receiving system and signal processing system are mainly used to detect the target and provide distance information.

[0004] With the widespread use of laser detection systems, the requirements for laser detection systems to resist smoke interference, detect with high signal-to-noise ratio, and detect with high precision are becoming increasingly higher. At present, the light source of laser detection systems mostly uses semiconductor lasers for distance detection. However, semiconductor lasers have disadvantages such as wide emission pulse width, low peak power, and wavelength drift with temperature changes. As a result, laser detection systems have problems such as inaccurate ranging and performance degradation in terms of precise distance determination and use in complex environments, which restricts the development and application of laser detection systems. Summary of the Invention

[0005] (1) Technical issues to be resolved

[0006] In view of the above problems, the present disclosure provides a miniaturized all-solid-state laser and a laser detection system to improve the problems of wide emission pulse width, low peak power, and wavelength drift with temperature changes in the current detection system using semiconductor lasers as light sources.

[0007] (2) Technical solution

[0008] One aspect of the present disclosure provides a miniaturized all-solid-state laser, comprising: a shift signal generation module for generating a plurality of shift square wave signals; a plurality of pulse constant current driving modules for converting the plurality of shift square wave signals into a plurality of constant pulse currents; a semiconductor laser array pumping module for generating a plurality of pumping light signals according to the plurality of constant pulse current driving modes; a laser bonding crystal for converting the plurality of pumping light signals into a plurality of nanosecond laser pulse signals by a passive Q-switching mode; a micro probe array module for monitoring the plurality of laser pulse signals and generating a plurality of negative pulse electrical signals synchronized with the plurality of laser pulse signals; an optical synchronization signal feedback module for converting the plurality of negative pulse electrical signals into a negative pulse synchronization feedback signal and inputting the negative pulse synchronization feedback signal into the plurality of pulse constant current driving modules to form a negative feedback network, so that each of the plurality of laser pulse signals generates only one laser pulse signal in a cycle; and an optical distribution module for changing the propagation direction of the plurality of laser pulse signals to make the plurality of laser pulse signals uniformly distributed in a field of view.

[0009] Optionally, the shift signal generation module comprises: a multivibrator for generating a frequency-adjustable pulse signal; and an N-sequence pulse generator for converting the pulse signal into the plurality of shift square wave signals.

[0010] Optionally, the plurality of pulse constant current driving modules comprises: a pulse signal generator for receiving the plurality of shift square wave signals and generating a plurality of pulse control signals with adjustable pulse width according to the rising edge of the signals; a triode for controlling the on-off of the triode by controlling the high-low of the gate level of the triode; a signal loading circuit for loading the plurality of pulse control signals to the gate of the triode to control the high-low of the gate level; a low-dropout linear regulator for outputting a constant voltage, the low-dropout linear regulator being connected with the triode to realize the switching of the working state of the low-dropout linear regulator by controlling the on-off of the triode; and a non-inductive thick film resistor for stabilizing the constant resistance between the OUT terminal and the GND terminal of the low-dropout linear regulator to generate the plurality of constant pulse currents in the loop.

[0011] Optionally, the semiconductor laser array pumping module comprises: a substrate; and a plurality of semiconductor laser dies, which are arranged at equal intervals on the substrate, the light emitting surface of the semiconductor laser dies being flush with the side of the substrate close to the laser bonding crystal, and the semiconductor laser dies and the substrate being closely attached to the laser bonding crystal; wherein one of the constant pulse currents is input to one of the semiconductor laser dies to generate a pumping light signal.

[0012] Optionally, the laser bonding crystal comprises: a gain medium crystal, configured to receive the plurality of pump light signals, realize a population inversion distribution state, and generate a plurality of laser pulse signals; a planar plane cavity, configured to provide positive feedback and mode selection for the plurality of laser pulse signals; and a passive Q-switching crystal, configured to change an absorption loss in a resonant cavity by using a saturable absorption characteristic of the passive Q-switching crystal, and compress the plurality of laser pulse signals into the plurality of laser pulse signals output at a high peak power.

[0013] Optionally, the micro probe array module comprises: a substrate; and a photodetector, disposed on the substrate, configured to receive the laser pulse signals leaked and reflected by the laser bonding crystal, generate a plurality of negative pulse electrical signals synchronized with the plurality of laser pulse signals, and transmit the plurality of negative pulse electrical signals to the optical synchronization signal feedback module through the substrate.

[0014] Optionally, the optical synchronization signal feedback module comprises: a monostable trigger, configured to input the plurality of negative pulse electrical signals to a falling edge trigger end of the monostable trigger, and input a negative pulse synchronization feedback signal generated at an output end of the monostable trigger to the pulse signal generator, so as to form a negative feedback network, make a current pump period end in advance, and realize that each of the plurality of laser pulse signals generates only one laser pulse signal in one period.

[0015] Optionally, the micro probe array module, the semiconductor laser array pump module, the laser bonding crystal and the optical distribution module are sequentially arranged along an optical path and the optical axes thereof coincide with each other.

[0016] Optionally, the system further comprises a heat dissipation module, configured to accelerate heat transfer of heat generated by the semiconductor laser array pump module and reduce a thermal effect of the laser bonding crystal.

[0017] Another aspect of the present disclosure provides a miniaturized laser detection system, comprising: a laser emission system, a receiving system and a signal processing system as described above; the laser emission system is configured to generate a laser pulse and send the laser pulse to a target; the receiving system is configured to receive a laser pulse reflected from the target and convert the laser pulse into a laser electrical signal; and the signal processing system is configured to process the laser electrical signal according to a set program, and complete ranging of the target.

[0018] (III) Advantages

[0019] The above at least one technical solution adopted by the embodiment of the present disclosure at least has the following advantages:

[0020] 1. Compared with the prior art of generating multiple laser pulse signals by setting multiple semiconductor lasers to pump multiple crystals, in the embodiment of the present disclosure, multiple semiconductor laser die arrays are arranged on the same substrate, combined with a laser bonded crystal, and the feasibility of generating multiple nanosecond laser pulse signals of the same and not interfering with each other using the same laser bonded crystal is proved by using semiconductor laser array end face pumping technology and passive Q switching technology. The structure of the laser detection system is compact, which not only improves the impact resistance of the laser detection exit system, but also makes it more miniaturized.

[0021] 2. The laser pulse signal generated by the all-solid-state laser has a narrower pulse width and a higher peak power. Meanwhile, the multiple laser pulse signals generated are distributed by an optical distribution module, and the multiple laser pulse signals are uniformly distributed in a 90° field of view for panoramic scanning detection. Therefore, compared with the conventional shaping and beam expanding of the semiconductor laser beam to a fan-shaped field of view, the laser pulse signal generated by the laser detection system of the embodiment of the present disclosure has stronger anti-smoke interference ability.

[0022] 3. By arranging the micro detection array module, the semiconductor laser array pumping module, the laser bonded crystal and the optical distribution module along the optical path in sequence and overlapping the optical axes with each other, and combining the optical feedback technology, frequency stable laser pulse signals can be generated by passive Q switching.

[0023] 4. The optical feedback technology can be realized by a simple circuit designed, which has strong practicality. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more completely understand the present disclosure and its advantages, reference will now be made to the following description taken together with the accompanying drawings, in which:

[0025] Figure 1 The overall structure schematic diagram of the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown;

[0026] Figure 2 The structure schematic diagram of the shift signal generation module in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown;

[0027] Figure 3 The structure schematic diagram of the multiple pulse constant current driving module in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown;

[0028] Figure 4 The structure schematic diagram of the semiconductor laser array pumping module in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown;

[0029] Figure 5A connection structure between the laser bonding crystal and the semiconductor laser array pumping module in the miniaturized all-solid-state laser is schematically shown;

[0030] Figure 6 A structure of the laser bonding crystal in the miniaturized all-solid-state laser is schematically shown;

[0031] Figure 7 A structure of the micro probe array module in the miniaturized all-solid-state laser is schematically shown;

[0032] Figure 8 A structure of the optical synchronization signal feedback module in the miniaturized all-solid-state laser is schematically shown;

[0033] Figure 9 A layout structure of the semiconductor laser array pumping module, the laser bonding crystal, the micro probe array module and the optical distribution module is schematically shown;

[0034] Figure 10 A layout structure between the substrate, the copper heat sink layer and the heat dissipation module is schematically shown;

[0035] Figure 11 A whole structure of a laser detection system is schematically shown.

[0036] Legend of reference signs:

[0037] 1 - shift signal generation module; 11 - multivibrator; 12 - N-bit sequential pulse generator; 2 - multi-channel pulse constant current driving module; 21 - pulse signal generator; 22 - signal loading circuit; 23 - triode; 24 - low dropout linear regulator; 25 - non-inductive thick film resistor; 26 - protection circuit; 3. semiconductor laser array pumping module; 31 - substrate; 32 - semiconductor laser die; 4 - laser bonding crystal; 41 - gain medium crystal; 42 - flat plane cavity; 43 - passive Q-switching crystal; 5 - micro probe array module; 51 - substrate; 52 - photodetector; 6 - optical synchronization signal feedback module; 61 - monostable trigger; 7 - optical distribution module; 8 - heat dissipation module; 9 - copper heat sink layer; 100 - laser detection system; 101 - laser emission system; 102 - receiving system; 103 - signal processing system. DETAILED DESCRIPTION

[0038] In order to make the objects, technical solutions and advantages of the present application clearer, the following further describes the present application with reference to the specific embodiments and accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of the present application.

[0039] The terms used herein are only used to describe specific embodiments, and are not intended to limit the present application. The terms "comprise", "include", and the like used herein indicate the presence of the stated features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0040] In the present application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" and the like should be understood in a broad sense, for example, can be fixed connection, can also be detachable connection, or integral; can be mechanical connection, can also be electrical connection or can communicate with each other; can be direct connection, or indirect connection through intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] In the description of the present application, it should be understood that the terms "longitudinal", "length", "circumferential", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the subsystems or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0042] Throughout the drawings, the same elements are denoted by the same or similar reference numerals. When it may cause confusion in understanding the present application, the conventional structure or configuration will be omitted. And the shape, size, positional relationship of each component in the drawing does not reflect the true size, proportion and actual positional relationship. In addition, in the claims, any reference symbol located between parentheses should not be construed as a limitation on the claims.

[0043] Similarly, to the extent that the foregoing description contains expressions of directions or orientations, such expressions are unless otherwise specified used for convenience in describing the implementation embodiments of the application in the context of the illustrations furnished herewith and in no way limit the application to any particular orientation or direction. Accordingly, the application includes all implementations falling within the scope of the appended claims, wherein reference to an article shall include all isomers and enantiomers of the article and racemic mixtures thereof, and also cover using the pure enantiomers, mixtures of enantiomers, or mixtures of the different isomers, where such isomers exist, unless specifically stated otherwise. The application includes all possible combinations of the individual limitations referred to or depicted in the appended claims.

[0044] In addition, the terms "first", "second", etc. are used herein only to describe various embodiments and their implementation, and do not connote an importance or a relative importance between the technical features referred to by such terms. Therefore, the features defined with "first", "second", etc. can explicitly or implicitly include one or more of the features. In the description of the application, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly specified.

[0045] The embodiments of the present disclosure provide a miniaturized all-solid-state laser.

[0046] Figure 1 The overall structure of the miniaturized all-solid-state laser according to the embodiments of the present disclosure is schematically shown.

[0047] Referring to Figure 1 The miniaturized all-solid-state laser may, for example, include a shift signal generation module 1, a multi-channel pulse constant current driving module 2, a semiconductor laser array pumping module 3, a laser-bonded crystal 4, a micro probe array module 5, an optical synchronization signal feedback module 6, an optical distribution module 7, and a heat dissipation module 8.

[0048] The shift signal generation module 1 is used to generate a plurality of shift square wave signals; the multi-channel pulse constant current driving module 2 is used to convert the plurality of shift square wave signals into a plurality of constant pulse currents; the semiconductor laser array pumping module 3 is used to generate a plurality of pumping light signals according to the multi-channel constant pulse current driving mode; the laser bonding crystal 4 is used to convert the plurality of pumping light signals into a plurality of nanosecond laser pulse signals through the passive Q switching mode; the micro probe array module 5 is used to monitor the plurality of laser pulse signals and generate a plurality of negative pulse electrical signals synchronized with the plurality of laser pulse signals; the optical synchronization signal feedback module 6 is used to convert the plurality of negative pulse electrical signals into a negative pulse synchronization feedback signal and input the negative pulse synchronization feedback signal into the multi-channel pulse constant current driving module 2, so as to form a negative feedback network, thereby ending the pumping stage of the current cycle in advance and realizing that each laser pulse signal generates only one laser pulse signal in a cycle; the optical distribution module 7 is used to change the propagation direction of the plurality of laser pulse signals, so as to uniformly distribute the plurality of laser pulse signals in a field of view; and the heat dissipation module 8 is used to accelerate the heat transfer of the semiconductor laser array pumping module 3 and reduce the heat effect of the laser bonding crystal 4.

[0049] Figure 2 The structure schematic diagram of the shift signal generation module 1 in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown.

[0050] Referring to Figure 2 According to the embodiment of the present disclosure, the shift signal generation module 1 comprises a multi-vibrator 11 and an N-ary sequential pulse generator 12. The multi-vibrator 11 is used to generate a pulse signal with adjustable frequency; and the N-ary sequential pulse generator 12 is used to convert the pulse signal into a plurality of shift square wave signals.

[0051] The multi-vibrator 11 generates a pulse signal with a specific frequency f, and the N-ary sequential pulse generator 12 converts the pulse signal into a plurality of shift square wave signals and sequentially outputs the plurality of shift square wave signals from different output ports. The N shift square wave signals form a cycle, and the frequency of each shift square wave signal is f / N. In the embodiment of the present disclosure, the multi-vibrator 11 generates a pulse signal with a frequency of 60 KHz, and a six-ary sequential pulse generator is taken as an example. The frequency of each shift square wave signal output by the six-ary sequential pulse generator is 10 KHz, and the six-ary sequential pulse generator can generate six shift square wave signals.

[0052] For example, the multi-vibrator 11 can also be a combination of a shift register and a digital circuit of a plurality of inputs or non-gate logic devices. In the embodiment of the present disclosure, the selection of the multi-vibrator 11 is not specifically limited, and can be selected according to the actual design of the system.

[0053] Figure 3 The structure schematic diagram of the multi-channel pulse constant current driving module 2 in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown.

[0054] Reference Figure 3 According to an embodiment of the present disclosure, a multi-channel pulse constant current driver module 2 includes: a pulse signal generator 21, a transistor 23, a signal loading circuit 22, a low-dropout linear regulator 24, a non-inductive thick-film resistor 25, and a protection circuit 26. The pulse signal generator 21, the transistor 23, the signal loading circuit 22, the low-dropout linear regulator 24, the non-inductive thick-film resistor 25, and the protection circuit 26 are all disposed on a PCB and connected by metal leads.

[0055] The pulse signal generator 21 is used to receive six-way shifted square wave signals and generate six-way pulse control signals with adjustable pulse width according to the triggering of the rising edge of the signal. The input end of each pulse signal generator 21 corresponds to each output of the shift signal generating module 1. The multi-way shifted square wave signals drive the multi-way pulse constant current driving module 2 to work in a preset order according to the rising edge of the signal; the transistor 23 is used to control the on and off of the transistor 23 by controlling the high and low gate level of the transistor 23; the signal loading circuit 22 is used to load the six-way pulse control signals to the transistor The gate of transistor 23 controls the gate voltage level. A low-voltage dropout linear regulator 24 is used to output a constant voltage. Connected to transistor 23, it switches its operating state by controlling the on / off switching of transistor 23. A non-inductive thick-film resistor 25 maintains a constant resistance between the OUT and GND terminals of the low-voltage dropout linear regulator 24, generating multiple constant pulse currents in the circuit and achieving constant voltage to constant current conversion. The high heat resistance of the non-inductive thick-film resistor 25 allows high currents to flow for extended periods. A protection circuit 26 protects the multi-pulse constant current driver module 2 from damage.

[0056] The low voltage drop linear regulator 24 can maintain a constant reference voltage V with high linearity at the ADJ terminal. REF , by changing the resistor divider network to achieve the voltage difference V between the OUT terminal and the GND terminal OUT-GND Adjustable; by slightly adjusting the voltage regulator circuit and adding a fixed value non-inductive thick film resistor 25 between the OUT terminal and the GND terminal, a constant maximum output current of 3A can be generated in the loop, realizing a high-stability constant current source.

[0057] The voltage difference between OUT and GND is V OUT-GND and ADJ terminal reference voltage V REF The following relationship is satisfied:

[0058]

[0059] R1 is the resistance between the OUT terminal and the ADJ terminal, and R2 is the resistance between the ADJ terminal and the GND terminal.

[0060] The ADJ terminal level of the low dropout linear regulator 24 is pulled high to be instant off, realizing the instantaneous switching of the working state, and the control is simple and efficient.

[0061] For example, the pulse signal generator can be a monostable trigger; the triode 23 is a high-speed NPN type, compared with a power MOS tube switch in series on the load, the triode 23 is used in the embodiment of the present disclosure, which can better realize the current stability and response characteristics.

[0062] Figure 4 The structure of the semiconductor laser array pumping module 3 in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown. Figure 5 The connection structure between the laser bonding crystal 4 and the semiconductor laser array pumping module 3 in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is schematically shown.

[0063] Referring to Figure 4 and Figure 5 According to the embodiment of the present disclosure, the semiconductor laser array pumping module 3 comprises a substrate 31 and a semiconductor laser die 32.

[0064] The semiconductor laser die 32 is provided with six, corresponding to six constant pulse currents, and the six semiconductor laser dies 32 are arranged at equal intervals on the substrate 31, wherein the two semiconductor laser dies 32 located in the middle of the substrate 31 have the shortest wavelength, the light emitting surface of the semiconductor laser die 32 is flush with the side of the substrate 31 close to the laser bonding crystal 4, and the semiconductor laser die 32 and the substrate 31 are closely attached to the laser bonding crystal 4.

[0065] Among them, the multi-channel pulse constant current driving module 2 generates six adjustable constant pulse currents within 3A, one constant pulse current is input to one semiconductor laser die 32, and the six semiconductor laser dies 32 realize transient response in the required pumping order, generating a wavelength of 808nm pump light signal.

[0066] Among them, the semiconductor laser array pumping module 3 and the laser bonding crystal 4 are arranged on the copper heat sink layer 9, and the semiconductor laser array pumping module 3 and the copper heat sink layer 9 are coated with a thickness of 0.1-0.5mm heat dissipation silicone grease to maintain good heat dissipation performance of the whole system; at the same time, the semiconductor laser array pumping module 3 and the laser bonding crystal 4 are closely attached to realize high power density pumping and improve the utilization efficiency of the pump light.

[0067] For example, the substrate 31 is made of ceramic material, which can be either aluminum nitride (AlN) or aluminum oxide (Al2O3). The AlN ceramic substrate 31 is used to promptly transfer the waste heat generated when the semiconductor laser die 32 is working, to prevent heat accumulation from burning the semiconductor laser die 32.

[0068] Figure 6 The schematic diagram of the structure of the laser-bonded crystal 4 in the miniaturized all-solid-state laser provided by the embodiment of the present disclosure is shown.

[0069] Reference Figure 6 The laser-bonded crystal 4 is used to provide the working medium and resonant cavity required for laser generation. The laser-bonded crystal 4 includes a gain medium crystal 41, a flat planar cavity 42, and a passively Q-switched crystal 43. The gain medium crystal 41 is used to receive six pump light signals, achieve a population inversion distribution state, and generate six laser pulse signals; the flat planar cavity 42 is used to provide positive feedback and mode selection for the six laser pulse signals; and the passively Q-switched crystal 43 is used to utilize the saturable absorption characteristics of the passively Q-switched crystal 43 to change the absorption loss in the resonant cavity, compressing the six laser pulse signals into six nanosecond laser pulse signals with a wavelength of 1064nm and outputting them at high peak power.

[0070] The gain medium crystal 41 and the passive Q-switched crystal 43 are connected by bonding, and the flat planar cavity 42 is realized between the two end faces of the laser-bonded crystal 4 by coating.

[0071] The gain medium crystal 41 is used to convert light energy into chemical energy stored in the crystal, realize the population inversion distribution state, and realize light amplification by stimulated emission. In the embodiment of the present disclosure, Nd:YAG crystal is selected as the gain medium crystal 41; the passive Q-switched crystal 43 can automatically adjust the loss in the resonant cavity according to the light intensity density in the resonant cavity. In the embodiment of the present disclosure, Cr-doped yttrium aluminum garnet (Cr-doped yttrium aluminum garnet) is selected as the gain medium crystal 41. 4+ The Nd:YAG crystal is used as a passive Q-switched crystal 43 to generate a narrow pulse width, high peak power laser pulse signal; the flat planar cavity 42 is used to provide positive feedback and mode selection for the laser pulse signal. The flat cavity is achieved by coating the two end faces of the laser bonded crystal 4 with high parallelism. The incident surface of the Nd:YAG crystal is coated with an 808nm laser anti-reflection film and a 1064nm laser total reflection film. 4+ The YAG crystal output surface is coated with a 808nm laser full reflection film and a 1064nm laser partial reflection film. The laser oscillates back and forth between the two end surfaces to achieve stimulated radiation amplification.

[0072] The passive Q-switching technology, that is, the passive Q-switching crystal 43 is used to change the absorption loss in the resonant cavity by using the passive Q-switching crystal 43 saturable absorption characteristics, the absorption coefficient of the saturable absorption crystal decreases with the increase of the incident light intensity, when reaching the saturation value, the passive Q-switching crystal 43 is 'bleached' and emits a pulse.

[0073] Figure 7 The structure schematic diagram of the micro detection array module 5 in the miniaturized all-solid-state laser is schematically shown.

[0074] Referring to Figure 7 According to the embodiment of the present disclosure, the micro detection array module 5 comprises a substrate 51 and a photodetector 52.

[0075] The substrate 51 is a PCB board, and the photodetector 52 is a PIN detector. The photodetector 52 is arranged on the substrate 51. The photodetector 52 of each channel is located directly behind the semiconductor laser die 32. The photodetector 52 is used to receive the reflected and leaked laser pulse signals when the laser bonding crystal 4 emits the laser pulse signals, to generate a plurality of negative pulse electrical signals synchronized with the plurality of laser pulse signals, and to transmit the plurality of negative pulse electrical signals to the optical synchronization signal feedback module 6 through the substrate 51.

[0076] Figure 8 The structure schematic diagram of the optical synchronization signal feedback module 6 in the miniaturized all-solid-state laser is schematically shown.

[0077] Referring to Figure 8 The optical synchronization signal feedback module 6 comprises a monostable trigger 61 (note that the monostable trigger in the above-mentioned pulse signal generator is different from the monostable trigger in the optical synchronization signal feedback module 6. Both are monostable triggers. In the drawings, the monostable trigger in the pulse signal generator is specifically expressed as a monostable trigger 1, and the monostable trigger 61 in the optical synchronization signal feedback module 6 is expressed as 2). The monostable trigger 61 is used to input the plurality of negative pulse electrical signals to the falling edge trigger end of the monostable trigger 61. After a plurality of negative pulse synchronization feedback signals are generated at the output end of the monostable trigger 61, the pulse signal generator 21 is input, a negative feedback network is formed, the current pumping period is ended in advance, only one laser pulse signal is generated in one period for each laser pulse signal, and the frequency stability of the passive Q-switching mode output laser pulse signal is realized.

[0078] Wherein, the falling edge trigger end of the monostable trigger 61 is used as the input end of the negative pulse electric signal, the falling edge trigger end of the monostable trigger 61 is connected to the high level of the power supply, and the photodetector 52 is reversely connected, the N pole of the photodetector 52 is connected to the input end of the negative pulse electric signal of the monostable trigger 61, the P pole of the photodetector 52 is connected to the ground of the power supply, the monostable trigger 61 is used as a photoelectric induction switch, each laser pulse signal can make the high level signal lower to the low level, so as to realize the falling edge trigger; the reverse output end of the monostable trigger 61 is connected to the enable end of each monostable trigger 61 of the multi-channel pulse constant current driving module, that is, in a cycle, once the laser pulse is generated, the high level stage ends in advance, so as to realize the feedback control of the multi-channel pulse constant current driving module.

[0079] For example, the 74hc123 chip with two monostable triggers 61 can be selected as the pulse signal generator 21 of the multi-channel pulse constant current driving module and the light feedback signal control chip of the light synchronization signal feedback module 6.

[0080] Figure 9 The layout structure schematic diagram of the semiconductor laser array pumping module, the laser bonded crystal, the micro detection array module and the optical distribution module provided by the embodiment of the present disclosure is schematically shown.

[0081] According to the embodiment of the present disclosure, the optical distribution module 7 is used to change the propagation direction of the multi-channel parallel equidistant laser pulse signals, so as to realize the uniform distribution of the multi-beam in the 90° field of view, and the optical distribution module 7 adopts a plano-convex rectangular cylindrical lens to convert the multi-channel parallel laser pulse signals into laser emission arrays with different angles. The embodiment of the present disclosure only needs to adopt a plano-convex rectangular cylindrical lens to realize the uniform distribution of the multi-channel laser pulse signals in the 90° field of view, so that only one plano-convex rectangular cylindrical lens needs to be fixed at the end of the system in the manufacturing process, thereby improving the impact resistance of the system.

[0082] Wherein, the micro detection array module 5, the semiconductor laser array pumping module 3, the laser bonded crystal 4 and the optical distribution module 7 are compactly arranged along the straight line where the optical path is located, and the optical axes are coincided with each other.

[0083] Figure 10 The layout structure schematic diagram between the substrate, the copper heat sink layer and the heat dissipation module provided by the embodiment of the present disclosure is schematically shown.

[0084] Referring to Figure 10 The heat dissipation module 8 includes a heat dissipation fin, the heat dissipation fin is arranged on the side of the copper heat sink layer 9 away from the substrate 31, and the heat dissipation fin and the copper heat sink layer 9 are coated with 0.1-0.5mm heat dissipation silicone grease, which can reduce heat accumulation and ensure the normal work of the semiconductor laser array pumping module 3.

[0085] The present disclosure further provides a laser detection system.

[0086] Figure 11 The overall structure of the laser detection system provided by the embodiments of the present disclosure is schematically shown.

[0087] Referring to Figure 11 The laser detection system 100 comprises the laser emission system 101, the receiving system 102 and the signal processing system 103 as described above.

[0088] The laser emission system 101 is configured to generate laser pulses and send them to the target; the receiving system 102 is configured to receive the laser pulses reflected from the target and convert them into laser electrical signals; and the signal processing system 103 is configured to process the laser electrical signals according to a preset program, complete the ranging of the target, and output the distance information.

[0089] The above embodiments further illustrate the technical solutions of the present disclosure. It should be understood that the above embodiments are merely specific embodiments of the present disclosure and are not intended to limit the present disclosure. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. A miniaturized all-solid-state laser, characterized in that: include: A shift signal generating module (1) is used to generate multiple shift square wave signals; A multi-channel pulse constant current driving module (2) is used to convert multi-channel shifted square wave signals into multi-channel constant pulse currents; A semiconductor laser array pump module (3) is used to generate multiple pump light signals according to the multiple constant pulse current driving modes; A laser bonded crystal (4) is used to convert the multiple pump light signals into multiple nanosecond laser pulse signals through passive Q-switching; A micro-detection array module (5) is used to monitor the multiple laser pulse signals and generate multiple negative pulse electrical signals synchronized with the multiple laser pulse signals; An optical synchronization signal feedback module (6) is used to convert multiple negative pulse electrical signals into negative pulse synchronization feedback signals and then input them into the multiple pulse constant current drive module (2), thereby forming a negative feedback network and achieving that each laser pulse signal generates only one laser pulse signal in one cycle; The optical distribution module (7) is used to change the propagation direction of the multiple laser pulse signals so that the multiple laser pulse signals are evenly distributed within the field of view.

2. The miniaturized all-solid-state laser according to claim 1, characterized in that: The shift signal generating module (1) comprises: A multivibrator (11) for generating a pulse signal with adjustable frequency; The N-ary sequential pulse generator (12) is used for converting the pulse signal into multiple shifted square wave signals.

3. The miniaturized all-solid-state laser according to claim 1, characterized in that: The multi-channel pulse constant current driving module (2) comprises: A pulse signal generator (21), the pulse signal generator being used to receive the multiple shifted square wave signals and to generate multiple pulse control signals with adjustable pulse widths according to the triggering of the rising edges of the signals; A triode (23) for controlling the on / off of the triode (23) by controlling the level of a gate of the triode (23); A signal loading circuit (22) is used for loading multiple pulse control signals onto the gate of the triode (23) to control the level of the gate; A low-voltage-difference linear regulator (24) is used to output a constant voltage. The low-voltage-difference linear regulator (24) is connected to the transistor (23), and the switching of the working state of the low-voltage-difference linear regulator (24) is achieved by controlling the on-off of the transistor (23); The non-inductive thick film resistor (25) is used to stabilize the resistance between the OUT terminal and the GND terminal of the low voltage difference linear regulator (24) to be constant, so that multiple constant pulse currents are generated in the loop.

4. The miniaturized all-solid-state laser according to claim 1, characterized in that: The semiconductor laser array pump module (3) comprises: substrate(31); A plurality of semiconductor laser tube cores (32) are provided, and the plurality of semiconductor laser tube cores (32) are arranged on a substrate (31) at equal intervals, and a light-emitting surface of the semiconductor laser tube core (32) is flush with a side of the substrate (31) close to the laser-bonded crystal (4), and the semiconductor laser tube core (32) and the substrate (31) are both bonded to the laser-bonded crystal (4); Wherein, one channel of the constant pulse current is input to one of the semiconductor laser tube cores (32) to generate a pump light signal.

5. The miniaturized all-solid-state laser according to claim 1, characterized in that: The laser bonded crystal (4) comprises: A gain medium crystal (41) is used to receive multiple pump light signals, realize a population inversion distribution state, and generate multiple laser pulse signals; A flat planar cavity (42) is used for providing positive feedback and mode selection for the multi-channel laser pulse signals; A passive Q-switched crystal (43) is used to change the absorption loss in the resonant cavity by utilizing the saturable absorption characteristics of the passive Q-switched crystal (43) for light, and to compress multiple laser pulse signals into multiple laser pulse signals and output them at high peak power.

6. The miniaturized all-solid-state laser according to claim 1, characterized in that: The micro detection array module (5) comprises: substrate (51); A photodetector (52) is provided on the substrate (51), and is used to receive the laser pulse signal reflected and leaked from the laser-bonded crystal (4), and to generate multiple negative pulse electrical signals synchronized with the multiple laser pulse signals. The multiple negative pulse electrical signals are transmitted to the optical synchronization signal feedback module (6) through the substrate (51).

7. The miniaturized all-solid-state laser according to claim 3, characterized in that: The optical synchronization signal feedback module (6) comprises: A monostable trigger (61) is used to input multiple negative pulse electrical signals into the falling edge trigger end of the monostable trigger (61), and after a negative pulse synchronous feedback signal is generated at the output end of the monostable trigger (61), the negative pulse synchronous feedback signal is input into the pulse signal generator (21), thereby forming a negative feedback network, so that the current pump cycle ends early, and each laser pulse signal generates only one laser pulse signal in one cycle.

8. The miniaturized all-solid-state laser according to claim 1, characterized in that: The micro-detection array module (5), the semiconductor laser array pump module (3), the laser bonding crystal (4) and the optical distribution module (7) are arranged in sequence along the optical path, and the optical axes thereof coincide with each other.

9. The miniaturized all-solid-state laser according to claim 1, characterized in that: It also includes a heat dissipation module (8), which is used to accelerate the transfer of heat generated by the semiconductor laser array pump module (3) and reduce the thermal effect of the laser bonded crystal (4).

10. A miniaturized laser detection system, characterized in that: include: The miniaturized all-solid-state laser according to any one of claims 1 to 9, further comprising a laser emission system (101), a receiving system (102), and a signal processing system (103); A laser emission system (101) is used to generate laser pulses and send them to a target; A receiving system (102) is used to receive laser pulses reflected from a target and convert them into laser electrical signals; The signal processing system (103) is used to process the laser electrical signal according to a set program to complete the distance measurement of the target.

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