CN105425373B - A kind of infrared continuous zooming optical system - Google Patents

Abstract

The invention discloses an infrared continuous zoom optical control system. The invention adopts two stepping motors to respectively drive the field of view variable power optical lens and the compensation optical lens to perform corresponding linear and nonlinear movements according to their respective optical requirements, so that the The control of the two optical lenses has simple real-time controllability and high-precision positioning.

Description

An infrared continuous zoom optical system

technical field

The invention relates to the technical field of detectors, in particular to an infrared continuous zoom optical control system.

Background technique

The continuous zoom optical control system achieves clear imaging of the target through the linkage of multiple optical lenses. At present, most of the traditional continuous zoom system control schemes are: use a DC motor to drive the focus compensation lens group to perform focus compensation, and another DC motor It directly drives the field of view variable power optical lens group to continuously zoom in the field of view. It requires that the guide groove of the cam mechanism for installing the field of view variable power optical lens group is a nonlinear curve, so the processing and assembly requirements for the cam are very strict, and the cam Processing errors are difficult to control and difficult to correct in the later stage, thus greatly reducing the positioning accuracy of the infrared continuous zoom optical system.

Contents of the invention

In view of the above analysis, the present invention aims to provide an infrared continuous zoom optical control system to solve the problem of low positioning accuracy of the infrared continuous zoom optical system in the prior art.

In order to solve the above problems, the present invention is mainly achieved through the following technical solutions:

The invention provides an infrared continuous zoom optical control system, which comprises: a stepping assembly of a zoom mirror and a stepping assembly of a compensation mirror;

The stepping assembly of the zoom mirror drives the zoom mirror in the optical-mechanical module to perform linear movement under the control of the microprocessor, so as to accurately position the zoom mirror;

The stepping component of the compensation mirror drives the compensation mirror in the optical-mechanical module to perform non-linear movement under the control of the microprocessor, so as to accurately position the compensation mirror.

Preferably, the zoom mirror stepping assembly includes a zoom mirror stepping motor, a zoom mirror guide rod and a zoom mirror assembly;

The stepper motor of the zoom mirror is connected with the guide rod of the zoom mirror, the zoom mirror assembly is arranged on the guide rod of the zoom mirror, and the step motor of the zoom mirror drives the zoom mirror under the control of the microprocessor The component moves linearly on the guide rod of the zoom lens, and the zoom lens component drives the zoom lens on it to perform linear movement, so as to precisely position the zoom lens.

Preferably, the stepping motor of the zoom mirror is provided with a first output shaft, and the linear movement of the zoom mirror assembly on the guide rod of the zoom mirror is controlled through the first output shaft.

Preferably, the compensation mirror stepping assembly includes a compensation mirror stepping motor, a compensation mirror guide rod and a compensation mirror assembly;

The compensation mirror stepping motor is connected to the compensation mirror guide rod, the compensation mirror assembly is arranged on the compensation mirror guide rod, and the compensation mirror stepping motor drives the compensation mirror under the control of the microprocessor The component moves nonlinearly on the guide rod of the compensating mirror, and the compensating mirror component drives the compensating mirror on it to perform nonlinear motion, so as to precisely position the compensating mirror.

Preferably, the stepping motor of the compensation mirror is provided with a second output shaft, and the nonlinear movement of the compensation mirror assembly on the guide rod of the compensation mirror is controlled through the second output shaft.

Preferably, the microprocessor calculates the frequency-step relationship according to the acceleration formula and the deceleration formula during acceleration and deceleration, and triggers the stepping motor of the zoom mirror and the stepping motor of the compensation mirror to move;

The acceleration formula is The deceleration formula is Among them, f is the pulse speed of the motor, g is the initial pulse speed, β is the acceleration during acceleration, m is the pulse sequence number, and a is the distance corresponding to the stepping motor of the zoom mirror and the stepping motor of the compensation mirror moving one microstep , G is the maximum pulse speed, γ is the acceleration during deceleration.

Preferably, the linear motion is the motion route of the zoom lens calculated according to the simulation;

The nonlinear motion is the motion path of the compensation mirror calculated according to the simulation.

Preferably, the microprocessor is also used to feed back the information of the stepping assembly of the zoom mirror, the stepping assembly of the compensating mirror and the optical-mechanical module to the host computer in real time.

Preferably, the optical-mechanical module includes a first reflector and a second reflector;

Wherein, the first reflecting mirror is arranged between the compensation mirror and the focusing mirror in the optical-mechanical module, and is used to reflect the optical path between the compensation mirror and the focusing mirror by 90 degrees;

The second reflecting mirror is arranged between the focusing mirror and the imaging lens in the optical-mechanical module, and is used to reflect the optical path between the focusing mirror and the imaging lens by 90 degrees .

The beneficial effects of the present invention are as follows:

The present invention adopts two stepping motors to respectively drive the field-of-view variable power optical lenses to perform corresponding linear and nonlinear movements according to their respective optical requirements, so that the two optical lenses have simple real-time controllability and high-precision positioning.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Description of drawings

FIG. 1 is a schematic structural view of an infrared continuous zoom optical system according to an embodiment of the present invention;

Fig. 2 is the stepper motor thrust and the pulse frequency curve schematic diagram of the embodiment of the present invention;

3 is a schematic structural diagram of an optical-mechanical module according to an embodiment of the present invention;

4 is a schematic diagram of a continuous zoom curve according to an embodiment of the present invention;

5 is a schematic diagram of infrared continuous zoom imaging according to an embodiment of the present invention;

6 is a schematic circuit diagram of an interface chip according to an embodiment of the present invention;

Fig. 7 is the schematic circuit diagram of the microprocessor of the embodiment of the present invention;

8 is a schematic circuit diagram of a stepper motor driver chip according to an embodiment of the present invention;

9 is a schematic circuit diagram of a power module according to an embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a stepping assembly of a zoom mirror and a stepping assembly of a compensating mirror according to an embodiment of the present invention.

detailed description

Preferred embodiments of the present invention will be specifically described below in conjunction with the accompanying drawings, wherein the accompanying drawings constitute a part of the application and are used together with the embodiments of the present invention to explain the principle of the present invention. For the sake of clarity and simplicity, detailed descriptions of known functions and constructions in the devices described herein will be omitted when it may obscure the subject matter of the present invention.

In order to solve the problem of low positioning accuracy of the prior art infrared continuous zoom optical system, the present invention provides an infrared continuous zoom optical system. The present invention will be further described in detail below with reference to the accompanying drawings and several embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

An infrared continuous zoom optical control system provided by an embodiment of the present invention, as shown in FIG. 1, the system includes: a stepping assembly of a zoom mirror and a stepping assembly of a compensation mirror;

The stepping assembly of the zoom mirror drives the zoom mirror in the optical-mechanical module to perform linear movement under the control of the microprocessor, so as to accurately position the zoom mirror;

The stepping component of the compensation mirror drives the compensation mirror in the optical-mechanical module to perform non-linear movement under the control of the microprocessor, so as to accurately position the compensation mirror.

The invention adopts the stepping assembly of the zoom mirror and the stepping assembly of the compensating mirror to respectively drive the variable power optical lens of the field of view to perform corresponding linear and nonlinear movements according to their respective optical requirements, so that the two optical lenses have simple real-time controllability and high precision positioning.

The zoom mirror stepping assembly described in the embodiment of the present invention includes a zoom mirror stepping motor, a zoom mirror guide rod, and a zoom mirror assembly;

The stepper motor of the zoom mirror is connected with the guide rod of the zoom mirror, the zoom mirror assembly is arranged on the guide rod of the zoom mirror, and the step motor of the zoom mirror drives the zoom mirror under the control of the microprocessor The component moves linearly on the guide rod of the zoom lens, and the zoom lens component drives the zoom lens on it to perform linear movement, so as to precisely position the zoom lens.

The invention realizes the precise control of the zoom mirror through the stepping assembly of the zoom mirror.

During specific implementation, the stepping motor of the zoom mirror in the embodiment of the present invention is provided with a first output shaft, and the linear movement of the zoom mirror assembly on the guide rod of the zoom mirror is controlled through the first output shaft.

The compensation mirror stepping assembly described in the embodiment of the present invention includes a compensation mirror stepping motor, a compensation mirror guide rod and a compensation mirror assembly;

The compensation mirror stepping motor is connected to the compensation mirror guide rod, the compensation mirror assembly is arranged on the compensation mirror guide rod, and the compensation mirror stepping motor drives the compensation mirror under the control of the microprocessor The component moves nonlinearly on the guide rod of the compensating mirror, and the compensating mirror component drives the compensating mirror on it to perform nonlinear motion, so as to precisely position the compensating mirror.

During specific implementation, a second output shaft is provided on the stepping motor of the compensation mirror according to the embodiment of the present invention, and the nonlinear movement of the compensation mirror assembly on the guide rod of the compensation mirror is controlled through the second output shaft.

During specific implementation, the microprocessor in the embodiment of the present invention calculates the frequency-step size relationship according to the acceleration formula and the deceleration formula when accelerating and decelerating, and triggers the stepping motor of the zoom mirror and the stepping motor of the compensation mirror exercise;

The acceleration formula is The deceleration formula is Among them, f is the pulse speed of the motor, g is the initial pulse speed, β is the acceleration during acceleration, m is the pulse sequence number, and a is the distance corresponding to the stepping motor of the zoom mirror and the stepping motor of the compensation mirror moving one microstep , G is the maximum pulse speed, γ is the acceleration during deceleration.

The linear motion in the embodiment of the present invention is the motion route of the zoom mirror calculated according to the simulation; the nonlinear motion is the motion route of the compensation mirror calculated according to the simulation.

The microprocessor in the embodiment of the present invention is also used to feed back the information of the stepping assembly of the zoom mirror, the stepping assembly of the compensation mirror and the optical-mechanical module to the host computer in real time.

The optical-mechanical module according to the embodiment of the present invention includes a first reflector and a second reflector;

Wherein, the first reflecting mirror is arranged between the compensation mirror and the focusing mirror in the optical-mechanical module, and is used to reflect the optical path between the compensation mirror and the focusing mirror by 90 degrees;

The second reflecting mirror is arranged between the focusing mirror and the imaging lens in the optical-mechanical module, and is used to reflect the optical path between the focusing mirror and the imaging lens by 90 degrees .

In order to better explain the system of the present invention, the system of the present invention will be described below in conjunction with Figures 1-10:

Fig. 1 is a schematic structural view of an infrared continuous zoom optical system according to an embodiment of the present invention. As shown in Fig. 1, the system specifically includes:

The electronics control module mainly consists of microprocessor, power supply, motor driver and motor.

The microprocessor module accepts the commands sent by the host computer through the interface chip, and feeds back the status to the host computer. The microprocessor sends a pulse signal to the motor driver chip after receiving the command, and the driver chip processes the signal sent by the microprocessor and sends it to the stepper motor to control the speed and direction of the stepper motor.

The continuous zoom optical-mechanical module is composed of four optical lenses and transmission structural components. The continuous zooming of the field of view is realized by controlling the linkage between the zoom lens and the compensation lens. The linkage of the zoom lens and the compensation lens in this module is through bearings and guide rails. Connect with two stepper motors.

The microprocessor module in the electronic control module is composed of C8051F121 chip and peripheral resistors and capacitors. What the interface chip chooses is MAX3070ESAD. Microprocessor C8051F121 receives host computer commands and sends status through interface chip MAX3070ESAD, and C8051F121 implements motor control algorithm calculation and motor control signal generation internally.

The power module is composed of a power chip LMZ14203, a power chip LT1763-3.3, a filter RN112 and peripheral resistors and capacitors. The power supply chip LMZ14203 converts the input 28V power supply into 5V voltage, which is supplied to the microprocessor and the driver chip. The power supply chip LT1763-3.3 converts the 5V voltage into 3.3V voltage and supplies it to the microprocessor. The filter RN112 realizes the filtering of the power supply, and filters out the noise on the power supply.

The driver chip in the control module pool is THB6128, its function is to receive the pulse-type motor control signal sent by the microprocessor, and convert it into 4-way phase-separated sinusoidal signals that can drive the stepping motor, and the four-way signals are respectively connected to Connected to the bipolar stepper motor line, the drive motor completes the movement according to the established steps.

The model of the stepping motor is E21H4AD-05, which is a hybrid bipolar stepping motor with a stepping accuracy of 0.02 mm. The optical components are driven by guide rails and bearings to realize continuous zooming. In order to avoid motor resonance out of step and improve motor positioning accuracy, the step accuracy is 16 differentials, and the motor speed and drive mode are set according to the characteristics of the selected step motor. The characteristics of the motor are shown in Figure 2:

Considering the compromise between the load and the variable speed, the maximum pulse speed of the control stepper motor is 800 steps per second, which involves the acceleration and deceleration process of the stepper motor. In order to prevent the stepper motor from losing steps during the acceleration and deceleration process, according to The acceleration formula can be derived as follows:

In the formula: f is the pulse speed of the motor, g is the initial pulse speed, β is the acceleration, m is the pulse sequence number, a is the distance corresponding to the motor moving one microstep, and a=0.00125mm in this scheme.

The derivation deceleration process is as follows:

In the formula: f is the pulse speed of the motor, G is the maximum pulse speed, γ is the acceleration, m is the pulse sequence number, and a is the distance corresponding to the motor moving one microstep.

The frequency-step relationship obtained by the above formula is converted into an array format and stored in the on-chip FLASH of the microprocessor, and the stepping motor calls this parameter when accelerating and decelerating.

The continuous zoom optical-mechanical module of the present invention mainly involves the linkage control technology of the zoom mirror and the compensation mirror, wherein the positions of the zoom mirror and the compensation mirror in the optical system are shown in Figure 3, and the optical movement of the zoom mirror and the compensation mirror in the invention The curve is shown in Figure 4.

As shown in Figure 4, the trajectory of the zoom lens is a linear motion (convenient for constant speed control), and the trajectory of the compensation mirror is a nonlinear motion. The Y axis represents the variation of the optical focal length value, and the X axis represents the distance between the zoom lens and the compensation lens relative to the front objective lens. Location. In the design, the two motion curves are divided into many discrete points, and they correspond one by one. The software control program makes the discrete points into an array and stores them in the Flash of the microprocessor. When the motor moves, the corresponding parameters are called.

Practice has proved that after adopting the system of the present invention, the infrared continuous zoom optical system has real-time adjustability, compensates for machining errors and errors generated after long-term wear of mechanical structures, and has a good compensation function. In the design of the invention, an optimized algorithm control design is made in the aspect of motor speed control, which avoids the step loss phenomenon of the motor and greatly improves the stability of the motor operation.

Fig. 5 is an imaging effect diagram of an infrared continuous zoom optical system with an infrared core matching a focal length of 40mm to 360mm based on the medium-wave 320×256 staring focal plane infrared detector assembly using the technology of the present invention. During the continuous zooming process, images can be clearly imaged. The imaging results are shown in Figure 5:

As shown in Figure 6, the UART_TX_PT and UART_RX_PT terminals of the interface chip MAX3070EASD are connected to the microprocessor, and the RX+, RX-, TX+ and TX- terminals are directly connected to the host computer to realize the serial port RS422 level conversion.

As shown in Figure 7, the microprocessor C8051F121 is connected to the interface chip through P0.0 and P0.1 ports (UART_TX_PT, UART_RX_PT), and receives and sends serial port information to the interface chip. The microprocessor internally stores the continuous zoom curve data, reads the curve data step by step during operation, and sends control signals to two stepper motor driver chips through the M1_EN, M1_CCW, M1_CLK, M2_EN, M2_CC and M2_CLK terminals through the internal program operation. Thereby driving the stepper motor to move as required. Among them, EN is the motor enabling signal, CCW is the motor steering control signal, and CLK is the motor rotation driving pulse.

As shown in Figure 8, the two interface chips THB6128 are connected to the microprocessor by M1_EN, M1_CCW, M1_CLK, M2_EN, M2_CC and M2_CLK terminals to receive the microprocessor motor control signal. Connect to the stepper motor through M1_OUT1A, M1_OUT1B, M1_OUT2A, M1_OUT2B, M2_OUT1A, M2_OUT1B, M2_OUT2A and M2_OUT2B. The driver chip converts the microprocessor motor control signal into a signal that can directly drive the motor through internal processing.

As shown in Figure 9, the input 28V power supply in the power module is first filtered by RN112 and inductor, part of the 28V power supply is directly supplied to the driver chip, and part of it is supplied to the voltage conversion chip LMZ14203. LMZ14203 converts the 28V voltage into 5V voltage, and the 5V voltage is supplied to the microprocessor, Driver chip and voltage conversion chip LT1763-3.3. The 5V input from the LT1763-3.3 is converted to the 3.3V required by the microprocessor.

As shown in Figure 10, the zoom mirror stepping assembly of the present invention comprises a zoom mirror stepping motor, a zoom mirror guide rod and a zoom mirror assembly, the zoom mirror stepping motor is connected with the zoom mirror guide rod, and the zoom mirror assembly is arranged on the zoom mirror guide rod. On the rod, the zoom mirror stepping motor drives the zoom mirror assembly to move linearly on the zoom mirror guide rod under the control of the microprocessor, and the zoom mirror assembly drives the zoom mirror on it to perform linear motion to accurately position the zoom mirror. The stepping motor of the zoom mirror is provided with a first output shaft, through which the linear movement of the zoom mirror assembly on the guide rod of the zoom mirror is controlled.

The compensation mirror stepping assembly of the present invention includes a compensation mirror stepping motor, a compensation mirror guide rod and a compensation mirror assembly, the compensation mirror stepping motor is connected with the compensation mirror guide rod, the compensation mirror assembly is arranged on the compensation mirror guide rod, and the compensation mirror step Under the control of the microprocessor, the motor drives the compensating mirror assembly to move nonlinearly on the compensating mirror guide rod, and the compensating mirror assembly drives the compensating mirror on it to perform non-linear motion so as to precisely position the compensating mirror. The compensation mirror stepping motor is provided with a second output shaft, and the compensation mirror assembly is controlled to move non-linearly on the compensation mirror guide rod through the second output shaft.

It should be noted that there are two guide rods for the compensation mirror and two guide rods for the zoom mirror in the present invention, so as to better maintain the smooth movement of the compensation mirror and the zoom mirror, and the zoom mirror assembly and the compensation mirror assembly in the embodiment of the present invention Each is one. The two zoom lens assemblies and the compensating lens assembly shown in FIG. 10 only illustrate the movable range of the assemblies.

The present invention adopts two stepping motors to respectively drive the field-of-view variable power optical lenses to perform corresponding linear and nonlinear movements according to their respective optical requirements, so that the two optical lenses have simple real-time controllability and high-precision positioning.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of changes or modifications within the technical scope disclosed in the present invention. Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (7)

1. a kind of infrared continuous zooming optical system, it is characterised in that including：Varifocal mirror stepping component and compensating glass stepping group Part；

The varifocal mirror stepping component, drives the varifocal mirror in bare engine module to carry out linear movement under control of the microprocessor, To be accurately positioned to the varifocal mirror；

The compensating glass stepping component, drives the compensating glass in bare engine module to carry out non-linear fortune under control of the microprocessor It is dynamic, to be accurately positioned to the compensating glass；

The varifocal mirror stepping component includes varifocal mirror stepper motor, varifocal mirror guide rod and zoom mirror assembly；

The varifocal mirror stepper motor is connected with the varifocal mirror guide rod, and the zoom mirror assembly is arranged on the varifocal mirror guide rod On, the varifocal mirror stepper motor drives the zoom mirror assembly linear in the varifocal mirror guide rod under control of the microprocessor Motion, the zoom mirror assembly drives varifocal mirror thereon to carry out linear movement, to be accurately positioned to the varifocal mirror；

The microprocessor calculates according to acceleration formula and deceleration formula in acceleration and deceleration and obtains frequency-step-length relation, and Trigger the varifocal mirror stepper motor and the compensating glass stepper motor is moved；

It is described acceleration formula beThe deceleration formula isWherein, f is motor pulses speed, and g is inceptive impulse speed, and β is acceleration, a A micro-stepping respective distances are moved for the varifocal mirror stepper motor and the compensating glass stepper motor, G is maximum impulse speed, γ is acceleration.

2. system according to claim 1, it is characterised in that

The varifocal mirror stepper motor is provided with the first output shaft, controls the zoom mirror assembly to exist by first output shaft The varifocal mirror guide rod linear motion.

3. system according to claim 1 or 2, it is characterised in that the compensating glass stepping component includes compensating glass stepping Motor, compensating glass guide rod and compensation mirror assembly；

The compensating glass stepper motor is connected with the compensating glass guide rod, and the compensation mirror assembly is arranged on the compensating glass guide rod On, the compensating glass stepper motor drives the compensation mirror assembly in the compensating glass guide rod under control of the microprocessor Nonlinear motion, the compensation mirror assembly drives compensating glass thereon to carry out linear movement, accurate to be carried out to the compensating glass Positioning.

4. system according to claim 3, it is characterised in that

The compensating glass stepper motor is provided with the second output shaft, controls the compensation mirror assembly to exist by second output shaft Nonlinear motion on the compensating glass guide rod.

5. system according to claim 1, it is characterised in that

The linear movement is the moving line of the varifocal mirror obtained according to simulation calculation；

The nonlinear motion is the moving line of the compensating glass obtained according to simulation calculation.

6. system according to claim 1, it is characterised in that

The microprocessor is additionally operable to the varifocal mirror stepping component, the compensating glass stepping component and the ray machine in real time The feedback of the information of module is to host computer.

7. system according to claim 1, it is characterised in that anti-including the first speculum and second in the bare engine module Penetrate mirror；

Wherein, first speculum is arranged in the bare engine module between compensating glass and focusing lens, for by the compensation Light path between mirror and the focusing lens carries out 90 degree of reflection；

Second speculum is arranged between the focusing lens and the imaging len in the bare engine module, for being adjusted described Light path between imaging len described in Jiao Jingyu carries out 90 degree of reflection.