阅读说明：本技术 一种微型激光探测装置及其控制方法 (Miniature laser detection device and control method thereof ) 是由 胡冬粤 周辉 冯建凡 张正洋 栾庆辉 于 2021-08-18 设计创作，主要内容包括：本发明涉及激光探测技术领域,具体涉及一种微型激光探测装置及其控制方法。包括四象限探测器、放大电路、反向比例运算反馈回路、增益控制模块和信号处理模块,每个反向比例运算反馈回路均包含并联设置的第一反馈回路和第二反馈回路；反向比例运算反馈回路用于通过第一反馈回路或第二反馈回路将放大电路输出的各路放大信号反馈至所述增益控制模块；增益控制模块用于根据各路反馈信号计算出对应的增益信号,并将各路增益信号输入至放大电路；信号处理模块用于根据采集的电压大小控制增益控制模块接通所述反向比例运算反馈回路的第一反馈回路或第二反馈回路。能够实现放大电路的高度集成,使激光探测装置的微型化设计成为可能。(The invention relates to the technical field of laser detection, in particular to a miniature laser detection device and a control method thereof. The system comprises a four-quadrant detector, an amplifying circuit, inverse proportion operation feedback loops, a gain control module and a signal processing module, wherein each inverse proportion operation feedback loop comprises a first feedback loop and a second feedback loop which are arranged in parallel; the inverse proportion operation feedback loop is used for feeding back each path of amplified signals output by the amplifying circuit to the gain control module through the first feedback loop or the second feedback loop; the gain control module is used for calculating corresponding gain signals according to the feedback signals of all paths and inputting the gain signals of all paths to the amplifying circuit; the signal processing module is used for controlling the gain control module to be connected with a first feedback loop or a second feedback loop of the inverse proportion operation feedback loop according to the acquired voltage. The high integration of the amplifying circuit can be realized, and the miniaturization design of the laser detection device becomes possible.)

1. A miniature laser detection device which characterized in that: the system comprises a four-quadrant detector, an amplifying circuit, inverse proportion operation feedback loops, a gain control module and a signal processing module, wherein the number of the inverse proportion operation feedback loops is consistent with that of voltage signal output ends of the four-quadrant detector, and each inverse proportion operation feedback loop comprises a first feedback loop and a second feedback loop which are arranged in parallel;

the four-quadrant detector is used for collecting optical signals, converting the optical signals into voltage signals and outputting the voltage signals to the amplifying circuit;

the amplifying circuit is used for synchronously amplifying the multi-path voltage signals input by the four-quadrant detector according to each gain signal input by the gain control module;

the inverse proportion operation feedback loop is used for feeding back each path of amplification signals output by the amplification circuit to the gain control module through a first feedback loop or a second feedback loop;

the gain control module is used for calculating corresponding gain signals according to the feedback signals of all paths and inputting the gain signals of all paths to the amplifying circuit;

the signal processing module is used for controlling the gain control module to be connected with a first feedback loop or a second feedback loop of the inverse proportion operation feedback loop according to the collected voltage.

2. The micro laser detection device according to claim 1, wherein: a plurality of voltage signal output ends of the four-quadrant detector are respectively connected with a plurality of voltage signal input ends of the amplifying circuit, a plurality of amplifying signal output ends of the amplifying circuit are respectively connected to feedback signal input ends corresponding to the gain control module through a reverse proportion operation feedback loop, each gain signal output end of the gain control module is respectively connected to a voltage signal input end corresponding to the amplifying circuit, and a control signal output end of the signal processing module is connected with a control signal input end of the gain control module.

3. The micro laser detection device according to claim 1, wherein: also comprises

When the signal processing module inputs a low-level control signal to the gain control module, the gain control module is connected with a first feedback loop of all inverse proportion operation feedback loops and is disconnected with all second feedback loops;

when the signal processing module inputs a high-level control signal to the gain control module, the gain control module is connected with the second feedback loops of all the inverse proportion operation feedback loops and is disconnected with all the first feedback loops.

4. The micro laser detection device according to claim 1, wherein: the first feedback loop comprises a first feedback capacitor and a first feedback resistor which are arranged in parallel, the second feedback loop comprises a second feedback capacitor and a second feedback resistor which are arranged in parallel, the capacitance of the first feedback capacitor is the same as that of the second feedback capacitor, and the resistance value of the first feedback resistor is smaller than that of the second feedback resistor.

5. The micro laser detection device according to claim 1, wherein: the gain control circuit comprises an amplifying circuit, a signal processing module and a buffer circuit, wherein the amplifying circuit is used for realizing voltage following, the amplifying signal output end of the amplifying circuit is connected to the signal processing module through the buffer circuit, and the signal processing module controls the gain control module according to the voltage input by the buffer circuit.

6. The micro laser detection device according to claim 1, wherein: the gain control module adopts a four-channel single-pole double-throw analog switch chip.

7. The micro laser detection device according to claim 5, wherein: the buffer circuit adopts a rail-to-rail input/output precision operational amplifier.

8. A method for controlling the micro laser detector apparatus according to claim 1, comprising:

the four-quadrant detector outputs a voltage signal to the signal processing module through the amplifying circuit;

when the voltage signal is smaller than the voltage threshold set by the signal processing module, the signal processing module controls the gain control module to switch on a second feedback loop of all inverse proportion operation feedback loops;

when the voltage signal is not less than the voltage threshold value set by the signal processing module, the signal processing module controls the gain control module to switch on a first feedback loop of all inverse proportion operation feedback loops;

the resistance value of the feedback resistor of the second feedback loop is larger than that of the feedback resistor of the first feedback loop.

9. The method for controlling a micro laser detector as claimed in claim 8, wherein all of the first feedback loops or the second feedback loops are turned on or off simultaneously.

Technical Field

The invention relates to the technical field of laser detection, in particular to a miniature laser detection device and a control method thereof.

Background

The laser semi-active guidance has the characteristics of high precision, strong anti-interference capability, simpler structure, low cost and convenient use, and can be widely applied to actual combat. The miniaturization of the laser detection device is an important development direction in the military field of all countries, and has a wide development prospect.

The existing laser detection device respectively adopts four amplifying circuits to respectively amplify signals of a four-quadrant detector aiming at four-path signal output of the four-quadrant detector. The four signal amplifying circuits are completely independent, so that the size of the four signal amplifying circuits is large, more wiring space is occupied, and the four signal amplifying circuits are not beneficial to the miniaturization design of the laser detection device.

Disclosure of Invention

The present invention is directed to overcome the drawbacks of the prior art, and an object of the present invention is to provide a micro laser detection device and a control method thereof, which can achieve high integration of an amplifier circuit, and enable a miniaturized design of the laser detection device.

The invention relates to a miniature laser detection device, which adopts the technical scheme that: the system comprises a four-quadrant detector, an amplifying circuit, inverse proportion operation feedback loops, a gain control module and a signal processing module, wherein the number of the inverse proportion operation feedback loops is consistent with that of voltage signal output ends of the four-quadrant detector, and each inverse proportion operation feedback loop comprises a first feedback loop and a second feedback loop which are arranged in parallel;

the four-quadrant detector is used for collecting optical signals, converting the optical signals into voltage signals and outputting the voltage signals to the amplifying circuit;

the amplifying circuit is used for synchronously amplifying the multi-path voltage signals input by the four-quadrant detector according to each gain signal input by the gain control module;

the inverse proportion operation feedback loop is used for feeding back each path of amplification signals output by the amplification circuit to the gain control module through a first feedback loop or a second feedback loop;

the gain control module is used for calculating corresponding gain signals according to the feedback signals of all paths and inputting the gain signals of all paths to the amplifying circuit;

the signal processing module is used for controlling the gain control module to be connected with a first feedback loop or a second feedback loop of the inverse proportion operation feedback loop according to the collected voltage.

Preferably, a plurality of voltage signal output ends of the four-quadrant detector are respectively connected with a plurality of voltage signal input ends of the amplifying circuit, a plurality of amplifying signal output ends of the amplifying circuit are respectively connected to feedback signal input ends corresponding to the gain control module through a reverse proportion operation feedback loop, each gain signal output end of the gain control module is respectively connected to a voltage signal input end corresponding to the amplifying circuit, and a control signal output end of the signal processing module is connected with a control signal input end of the gain control module.

Preferably, also comprises

When the signal processing module inputs a low-level control signal to the gain control module, the gain control module is connected with a first feedback loop of all inverse proportion operation feedback loops and is disconnected with all second feedback loops;

when the signal processing module inputs a high-level control signal to the gain control module, the gain control module is connected with the second feedback loops of all the inverse proportion operation feedback loops and is disconnected with all the first feedback loops.

Preferably, the first feedback loop comprises a first feedback capacitor and a first feedback resistor which are arranged in parallel, the second feedback loop comprises a second feedback capacitor and a second feedback resistor which are arranged in parallel, the capacitance of the first feedback capacitor is the same as that of the second feedback capacitor, and the resistance of the first feedback resistor is smaller than that of the second feedback resistor.

Preferably, the gain control circuit further comprises a buffer circuit, the buffer circuit is used for realizing voltage following, an amplified signal output end of the amplifying circuit is connected to the signal processing module through the buffer circuit, and the signal processing module controls the gain control module according to the voltage input by the buffer circuit.

Preferably, the gain control module adopts a four-channel single-pole double-throw analog switch chip.

Preferably, the buffer circuit adopts a rail-to-rail input/output precision operational amplifier.

The invention discloses a control method of a miniature laser detection device, which adopts the technical scheme that the control method comprises the following steps:

the four-quadrant detector outputs a voltage signal to the signal processing module through the amplifying circuit;

when the voltage signal is smaller than the voltage threshold set by the signal processing module, the signal processing module controls the gain control module to switch on a second feedback loop of all inverse proportion operation feedback loops;

when the voltage signal is not less than the voltage threshold value set by the signal processing module, the signal processing module controls the gain control module to switch on a first feedback loop of all inverse proportion operation feedback loops;

the resistance value of the feedback resistor of the second feedback loop is larger than that of the feedback resistor of the first feedback loop.

Preferably, all of the first feedback loops or the second feedback loops are switched on or off simultaneously.

The invention has the beneficial effects that:

1. the gain control module and the amplifying circuit are used for synchronously controlling the gain switching of the four quadrant output signals of the detector, a plurality of paths of amplifying circuits are not needed, the circuit integration level is greatly improved, and the micro laser detection device is favorably designed in a micro mode.

2. The inverse proportion operation feedback loop adopts a double feedback loop design, and selective access of the feedback loop is realized through the signal processing module according to the acquired voltage, so that the adjustment of the amplification factor is realized. The structure enables the detector to adjust the amplification factor according to the distance of the detected object, so that the detected object can have better signal output quality at any position.

Drawings

FIG. 1 is a schematic view of the connection principle of the present invention;

FIG. 2 is a schematic diagram of a four quadrant detector of the present invention;

FIG. 3 is a schematic diagram of an amplifying circuit according to the present invention;

FIG. 4 is a schematic diagram of a gain control module according to the present invention;

FIG. 5 is a schematic diagram of an inverse proportional operation feedback loop according to the present invention;

FIG. 6 is a schematic view of a buffer module according to the present invention;

FIG. 7 is a schematic diagram illustrating the principle of inverse scaling operation amplification according to the present invention;

FIG. 8 is a diagram of a four-channel single-pole double-throw analog switch chip.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

As shown in fig. 1, the micro laser detection device of the present invention includes a four-quadrant detector, an amplifying circuit, inverse proportional operation feedback loops, a gain control module and a signal processing module, wherein the number of the inverse proportional operation feedback loops is the same as the number of voltage signal output ends of the four-quadrant detector, and each of the inverse proportional operation feedback loops includes a first feedback loop and a second feedback loop that are arranged in parallel;

the four-quadrant detector is used for collecting optical signals, converting the optical signals into voltage signals and outputting the voltage signals to the amplifying circuit;

the amplifying circuit is used for synchronously amplifying the multi-path voltage signals input by the four-quadrant detector according to each gain signal input by the gain control module;

the inverse proportion operation feedback loop is used for feeding back each path of amplification signals output by the amplification circuit to the gain control module through a first feedback loop or a second feedback loop;

the gain control module is used for calculating corresponding gain signals according to the feedback signals of all paths and inputting the gain signals of all paths to the amplifying circuit;

the signal processing module is used for controlling the gain control module to be connected with a first feedback loop or a second feedback loop of the inverse proportion operation feedback loop according to the collected voltage.

Preferably, a plurality of voltage signal output ends of the four-quadrant detector are respectively connected with a plurality of voltage signal input ends of the amplifying circuit, a plurality of amplifying signal output ends of the amplifying circuit are respectively connected to feedback signal input ends corresponding to the gain control module through a reverse proportion operation feedback loop, each gain signal output end of the gain control module is respectively connected to a voltage signal input end corresponding to the amplifying circuit, and a control signal output end of the signal processing module is connected with a control signal input end of the gain control module.

Preferably, also comprises

When the signal processing module inputs a low-level control signal to the gain control module, the gain control module is connected with a first feedback loop of all inverse proportion operation feedback loops and is disconnected with all second feedback loops;

when the signal processing module inputs a high-level control signal to the gain control module, the gain control module is connected with the second feedback loops of all the inverse proportion operation feedback loops and is disconnected with all the first feedback loops.

Preferably, the first feedback loop comprises a first feedback capacitor and a first feedback resistor which are arranged in parallel, the second feedback loop comprises a second feedback capacitor and a second feedback resistor which are arranged in parallel, the capacitance of the first feedback capacitor is the same as that of the second feedback capacitor, and the resistance of the first feedback resistor is smaller than that of the second feedback resistor.

Preferably, the gain control circuit further comprises a buffer circuit, the buffer circuit is used for realizing voltage following, an amplified signal output end of the amplifying circuit is connected to the signal processing module through the buffer circuit, and the signal processing module controls the gain control module according to the voltage input by the buffer circuit.

Preferably, the gain control module adopts a four-channel single-pole double-throw analog switch chip.

Preferably, the buffer circuit adopts a rail-to-rail input/output precision operational amplifier.

In the simulated projectile flying process, the projectile flies from far to near relative to the target, and the received laser radiation intensity is stronger and stronger. The laser detection device gradually approaches the saturation state from the lowest responsivity that is farthest able to receive the laser radiation during flight. Based on the above situation, the working process of the device is as follows:

when the laser detector is in a long distance, the laser detector receives weak laser radiation energy, and an amplifying circuit is needed to amplify the output electric signal. The gain control circuit switches the inverse proportion operation feedback loop to the second feedback loop, and the amplification factor of the amplifying circuit to the output signal is improved.

When the distance between the detection objects becomes close, the laser radiation energy received by the laser detection device becomes stronger, and when the amplified output signal reaches the output rated value of the integrated operational amplifier (the actual value is lower than the rated value, and a margin is reserved), the gain control circuit can switch the inverse proportion operation feedback loop to the first feedback loop, so that the amplification factor of the amplification circuit to the output signal is reduced.

Through the control mode, the optimal signal output of the detected object under different distances can be realized.

Example one

This embodiment describes the apparatus with reference to a specific circuit configuration.

As shown in fig. 2, the four-quadrant detector converts the optical signal into an electrical signal through U1, and outputs 4 voltage signals AX, BX, CX, and DX to the amplifying circuit through the output terminal.

As shown in fig. 3, the low power consumption amplifier D1 of the amplifying circuit has 4 signal inputs for receiving AX, BX, CX, DX signals, respectively, and simultaneously receiving the corresponding gain signals INA-, INB-, INC-, IND-. D1 amplifies and outputs the signals according to the input voltage signal and gain signal, and outputs OUTA, OUTB, OUTC, and OUTD are input to each corresponding inverse proportional operation feedback loop.

As shown in FIG. 4, the gain control module uses low-resistance analog switch chips D2 and D2 to receive a control signal CTRL, and controls channels SA1-, SB1-, SC 1-and SD 1-to be switched on or SA2-, SB2-, SC 2-and SD 2-to be switched on through the high/low level of CTRL. Meanwhile, the feedback loop outputs gain signals INA, INB, INC and IND according to feedback signals INA1, INB1, INC1 and IND1 or INA2, INB2, INC2 and IND2 which are input by the inverse proportion operation feedback loop.

As shown in fig. 5, the inverse proportional operation feedback loop includes 4 independent loops, each having the same circuit result, and each having two feedback loops.

When the voltage signal is smaller than the voltage threshold set by the signal processing module, the signal processing module controls the gain control module to switch on the second feedback loops of all the inverse proportion operation feedback loops, and the feedback signals output by the inverse proportion operation feedback loops are INA2-, INB2-, INC 2-and IND 2-;

when the voltage signal is not less than the voltage threshold set by the signal processing module, the signal processing module controls the gain control module to switch on the first feedback loops of all the inverse proportion operation feedback loops, and the feedback signals output by the inverse proportion operation feedback loops are INA1-, INB1-, INC 1-and IND 1-.

The capacitance of the first feedback capacitor is the same as that of the second feedback capacitor, the value of the first feedback capacitor is 108pF, the resistance of the first feedback resistor is smaller than that of the second feedback resistor, the resistance of the first feedback resistor is 1k Ω, and the resistance of the second feedback resistor is 12k Ω.

The principle of the inverse proportional operational amplifier circuit is shown in fig. 7:

it is known that

V+＝0 (1)

Is derived from the virtual shortness

V+＝V- (2)

Because VN and V-are equipotential

VN＝0 (3)

I＝0 (4)

The node current analysis of the N points comprises the following steps:

Ii＝-If (5)

Vi/R1＝-Vo/Rf (6)

then there are: vo ═ Vi x (Rf/R1) (7)

That is, the formula (7) is to obtain the magnitude of the output voltage according to the input voltage.

As shown in fig. 6, the buffer circuit is a rail-to-rail input/output precision operational amplifier for implementing voltage following, reducing signal loss and improving signal quality. The input signals are output signals OUTA, OUTB, OUTC, and OUTD of the amplifier circuit, and the output signals OUTAX, OUTBX, OUTCX, and OUTDX, which are input to the signal processing module.

Example two

As shown in fig. 8, the D2 of the gain control module of this embodiment uses a four-channel single-pole double-throw analog switch chip, which uses a single output with two inputs, and if one of the inputs is connected to the output, the other input is an open circuit. The gain multiple is controlled by controlling the high and low level of the IN pin to determine which input and output are connected, and the gain multiple is controlled (the method can also be used for realizing single-pole multi-throw and the like, and controlling more gain multiples). A four-channel single-pole double-throw analog switch chip can synchronously control the gain switching of four quadrant output signals of the detector.

EN # of the four-channel single-pole double-throw analog switch chip is a chip enabling signal pin, the low level is effective, and the signal is grounded to enable the chip to work normally after being electrified; IN is a control signal input pin selected by different channels, a 1# terminal is selected at low level (S1x), a 2# terminal is selected at high level (S2x), and channel selection is performed by a control signal CTRL given on a subsequent stage signal processing board.

When the four-quadrant detector is selected, factors such as sensitive surface area, light responsivity, response speed, noise dark current, flux threshold, junction capacitance, consistency of light responsivity of each quadrant and the like need to be considered, wherein the most important factor is the consistency of the flux threshold and the light responsivity of each quadrant. These parameters will directly affect the accuracy of the probe location and the speed of guidance. The following analysis was performed for the main parameters:

a) area of photosensitive surface

The area of the photosensitive surface determines the detection field range of the seeker, the larger the area is, the larger the field is, but the larger the photosensitive surface is, the larger the junction capacitance of the detector is, and the lower the response speed of the detector is caused. In addition, the photosensitive surface is large and is greatly influenced by background light, so that the signal to noise ratio is reduced, and therefore, when the four-quadrant detector is selected, the four-quadrant detector with the appropriate size of the photosensitive surface is selected according to the specific application environment of the optical receiving system in comprehensive consideration.

b) Spectral responsivity

The high and low of the spectral responsivity of the four-quadrant detector determines the receiving sensitivity of the whole system. Four-quadrant PIN photodiode, four-quadrant APD photodiode and four-quadrant silicon photocell detector, sensitive to laser with 1.064 μm as central waveband, with response peak value starting from 0.4 μm and extending to 1.l μm, so the depletion layer thickness of the photosensitive surface of the detector is required to be as thick as possible, but with the problems of increase of photo-generated carrier transit time and working bias voltage, etc., so consideration is also given.

c) Speed of response

The response speed is an important parameter for the guided weapon, and directly influences the real-time performance of guidance. Generally defined as the time required for the output signal to rise from 10% to 90% of the peak value. For a fully depleted photodetector, the response speed is mainly determined by the transit time of photogenerated carriers in the depletion layer, the RC time constant and other factors. If a fast response speed is required, the depletion layer must be thin and the photosensitive area must be small. Therefore, the parameters are comprehensively considered in combination with parameters such as photosensitive area, responsivity, working reverse bias voltage and the like, and a proper detector is selected by adopting a compromise method.

d) Flux threshold Pth

The flux threshold Pth of the four quadrant detector indicates the power of the minimum light pulse signal that can be detected by the detector, in (W). For a PIN photodiode detector, the sensitivity threshold is on the order of about 10-7 to 10-8 (W).

e) Isolation of picture elements

In order to improve the utilization of the energy of the light spot, the gaps between the pixels cannot be made large, so that the crosstalk between the pixels is a problem. For a four-quadrant photoelectric detector for guidance, good isolation among all pixels is beneficial to reducing system errors and improving the positioning accuracy of a seeker system. The picture elements are usually isolated by PN junctions and have certain 'dead zones', and the size of the 'dead zones' is related to the design level and the manufacturing process of the device.

f) Quadrant photoelectric responsivity

The photosensitive surface has to ensure higher photoelectric response consistency and has strict requirements on the materials and the manufacturing process of devices. At present, in a photovoltaic four-quadrant detector on the market, the small nonuniformity of a photosurface can be controlled within 6%, and the large nonuniformity of the photosurface is 10% -25%. The non-linear error of the four-quadrant detector tracking positioning system is mainly generated by the non-uniformity of the detector, and in order to reduce the non-linear error, the sensitivity is constant in the whole measuring range, and a correction measure needs to be taken.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.