Detailed Description
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
The imaging schematic diagram (fig. 2) of the embodiment of the present invention shows how the light beam is split into two parts by the beam splitting prism 3 after passing through the collimator objective 4, and light spots are formed on the first area array detector 1 and the second area array detector 2. In addition, it includes information on how to calculate the angle and position change of the beam.
The overall structure diagram (fig. 3) shows all components of the beam detection locator and their relative positions. This includes the positions of the collimator objective, the beam splitting prism, and the two area array detectors.
The beam sensing positioner assembly positions (fig. 4) detail the exact position of each assembly and their positional relationship in the device.
The front view of the beam dump positioner (fig. 5), the top view of the beam dump positioner (fig. 6), and the side view of the beam dump positioner (fig. 7) show the appearance of the device from different angles, including all important components such as the collimator objective, the beam splitting prism, and the external layout of the two area array detectors.
In the device, the collimator objective 4 is the first component to encounter the light beam. Its task is to focus the beam to a specific point.
The beam splitter prism 3 then splits this focused beam into two parts, which are dispersed in two different directions.
Next, there is a first area detector 1 and a second area detector 2. Each area array detector is placed at a focal plane and receives two light beams dispersed by the beam splitter prism. They all convert the energy of the respective spot into an electrical signal and measure the centroid position of the spot.
When the angle or position of the light beam changes, the position of the light spot received by the area array detector also changes. By comparing and analyzing the signals received by the two area array detectors, the angle and the position offset of the light beam can be calculated.
Thus, in this arrangement, the collimator lens 4 is at the input end, the first area array detector 1 and the second area array detector 2 are at the output end, and the beam splitting prism 3 is between the two, responsible for dispersing the focused beam onto the two area array detectors.
Aiming at the problems in the prior art, the invention provides a method, a system, equipment and a terminal for optimizing data synchronization among serial chips, and the invention is described in detail below with reference to the accompanying drawings.
1. Hardware overall scheme
The beam detection positioning instrument provided by the embodiment of the invention adopts the double-light-path front-back defocused light path to measure the angle and the position offset of the laser beam.
The light path of the beam detection positioning instrument is shown in fig. 1, the light beam is converged through the collimating objective lens 4, and the converging light beam is split into two parts by the splitting prism 3 arranged behind the collimating objective lens 4 and is converged into a minimum light spot at the focal plane positions of the two directions. The two area array detectors are respectively positioned in front of and behind the two focal planes, receive the energy of the scattered light spots of the two area array detectors, and measure the centroid positions of the two scattered light spots. When the angle or displacement of the incident light beam is changed, the positions of the light spots received by the two area array detectors are also changed, and the angle and displacement of the incident light beam can be calculated according to the rule of the displacement of the two light spots.
The mechanical processing piece adopts an aluminum alloy material, the aluminum alloy has low density and high strength, and has good mechanical property, physical property and corrosion resistance after heat treatment, and the hollow processing is carried out on part of the modules on the premise of not influencing the stability, so that the total weight of the material is reduced, and the stability and weight limitation of the whole machine are ensured. Meanwhile, the base of the whole machine of the instrument adopts grinding treatment, and the flatness of the control bottom surface can be used as a mounting reference surface of the whole machine.
2. Software overview scheme
The light beam detection positioning instrument provided by the embodiment of the invention adopts C++ as a programming language in software, on one hand, the reason is that the software needs to call an SDK dynamic link library of hardware modules such as an area array detector, a linear module driver and the like, the call is most direct by using C++ without re-encapsulation, and the call is a primary interface, so that the realization function is more flexible, and the operation efficiency is high; secondly, C++ adopts an object-oriented structured program design, and is used for realizing clear program hierarchy, clear code structure and easy maintenance; and the number of C++ dependent components and static/dynamic link libraries is less, and the code deployment is more convenient.
The software core module adopts an interface-oriented programming concept, the front end and the rear end are decoupled to the greatest extent in the framework, and the whole software is divided into three layers: the bottom hardware control and data acquisition, middle data processing and transmission, upper data display and interactive operation, and reasonable layering ensures that the modification or update of each module does not influence the normal operation of other modules. Meanwhile, the software bottom layer adopts a plug-in loading mode, and under the condition that an interface is unchanged, hardware is upgraded or changed, only the plug-in is required to be reissued, and other parts do not need to be changed.
And carrying out digital processing on a target image of the light beam detection positioning instrument, extracting target characteristics from an original image by adopting an image subdivision fitting means, and obtaining the accurate sub-pixel position of the target.
According to the imaging principle of the light beam passing through the lens, as shown in fig. 2, an imaging formula of the light beam with angle and offset passing through the collimating objective lens 4 is deduced, and the angle deflection and the position offset of the incident light beam are reversely deduced; from the imaging light path shown in fig. 2, the basic imaging formula can be obtained:
wherein H is the displacement of the light spot measured on the array detector, d is the distance between the detector and the focal plane, f is the effective focal length of the collimator objective lens, A is the angle, and H is the displacement.
The angle and displacement calculation formula:
wherein d1 Probing for a first area arrayDistance between the device and the focal plane d2 H is the distance between the second area array detector and the focal plane1 Is the displacement of the light spot measured on the first area array detector, h2 The displacement of the light spot measured on the second area array detector is f which is the effective focal length of the collimating objective lens, A is the angle, and H is the displacement.
3. Structural scheme
As shown in FIG. 3, the light beam measuring instrument provided by the embodiment of the invention has the advantages that the whole structure is made of aluminum alloy materials, the aluminum alloy has low density and high strength, and the aluminum alloy has good mechanical property, physical property and corrosion resistance after heat treatment, so that the stability and weight limitation of the whole instrument are ensured.
The instrument structure mainly comprises two structural members, a complete machine assembly and a spectroscope assembly, as shown in fig. 4, wherein the complete machine assembly is used for fixing a collimating objective 4 and two area array detectors, the spectroscope assembly is used for fixing a spectroscope 3, and the spectroscope assembly can finely adjust angles in horizontal and vertical directions through screw holes and jackscrews so as to ensure the coaxiality of double light paths in the assembly process.
4. Main content of technical attack
(1) Double-light-path defocusing system algorithm
The general beam measuring instrument is generally divided into an infinity conjugate system and a finite distance conjugate system, wherein the infinity conjugate system is insensitive to the position deviation of the beam and can only measure the angle deflection of the beam, such as a telescope, an autocollimator and the like; the finite distance conjugate system generally measures the displacement of a finite object from a target, and is insensitive to angular deflection, such as a microscopic system, a telecentric system, and the like. The beam detection positioning instrument provided by the embodiment of the invention adopts a novel double-light-path defocusing system to measure the angle deflection and the position deflection of the laser beam at the same time, and the angle deflection and the displacement of the beam are calculated reversely on two image planes for determining the defocusing amount according to the light transmission path.
(2) Accuracy of optical target extraction
The measuring precision and stability of the beam detecting and positioning instrument mainly depend on the extracting precision of the target position, and because of the defocused measuring system adopted by the scheme, the imaging of the laser beam on the detector is not a small perfectly converged light spot, but a diffuse spot, so that the diffuse spot needs to be subjected to graphic processing, and the accurate target position is obtained.
(3) Weight limitation of the whole machine
Since the beam detector is operated as a single instrument or as a sensor integrated in other systems, the weight of the whole machine is limited.
5. Key technology and solving means
The collimated laser beam is converged on the focal plane of the objective lens through the collimating objective lens 4, the convergence point on the focal plane is only sensitive to the angle change of the beam, the convergence light spot can be displaced according to the tan relation when the angle of the beam deflects, and the position of the light spot is not changed when the beam translates. The defocused plane is sensitive to not only the deflection angle of the light beam, but also the translation of the light beam, and the light spot position on the final plane is the integrated value of the angle and the translation variation. However, the angular and translational changes of the beam cannot be resolved from the spot displacement of one defocusing plane, so after the collimator objective 4, the laser beam is converged on two planes with different defocusing amounts by the beam splitter, and is received by the two area array detectors, and the angular deflection and translational values of the laser beam are resolved by the two imaging formulas, and the specific process is shown in fig. 2.
According to the imaging light path, a basic imaging formula can be obtained:
wherein H is the displacement of the light spot measured on the array detector, d is the distance between the detector and the focal plane, f is the effective focal length of the collimator objective lens, A is the angle, and H is the displacement.
The two detectors are respectively positioned at a distance from the focal plane d1 And d2 Deriving an angle and displacement calculation formula of the beam from the formula, wherein h1 And h2 The displacement of the light spot measured on the two detectors, f is the effective focal length of the collimator objective 4:
wherein d1 D is the distance between the first area array detector and the focal plane2 H is the distance between the second area array detector and the focal plane1 Is the displacement of the light spot measured on the first area array detector, h2 The displacement of the light spot measured on the second area array detector is f which is the effective focal length of the collimating objective lens, A is the angle, and H is the displacement.
The beam detection positioning instrument receives two laser beams which are converged round light spots with the diameter of 130-260 mu m at +/-5 mm of the focal plane of the collimating objective lens 4. The method comprises the steps of extracting the circle center position of a circular light spot, performing a centroid method, hough circle detection, edge fitting and the like by common algorithms, extracting edge information of sub-pixels of the light spot by using gradient information of the edge brightness of the light spot in a circle fitting mode, connecting the edge information into a complete contour, performing circle fitting on the contour, and finally extracting the circle center position of the fitted circle. The algorithm is less influenced by brightness change and the shape of the light spot, the actual measurement final precision can be better than 1/5 pixel, and the final precision is 1 micron calculated according to 4.8 microns of the pixel of the current area array detector.
The angle and displacement calculation formula deduced in the foregoing is the following formula:
wherein d1 D is the distance between the first area array detector and the focal plane2 For a second area detector and focal planeDistance, h1 Is the displacement of the light spot measured on the first area array detector, h2 The displacement of the light spot measured on the second area array detector is f which is the effective focal length of the collimating objective lens, A is the angle, and H is the displacement.
Wherein the system parameter d1 ＝5mm，d2 The measurement accuracy obtained by substituting f=50mm with = -5mm and δa=0.001°, δh=0.001 mm into the above formula.
The machined part adopts an aluminum alloy material, and the aluminum alloy has low density and high strength, and has good mechanical property, physical property and corrosion resistance after heat treatment. In the structural design, on the premise of not influencing the stability of the instrument, the non-key parts are hollowed out and the like, so that the total volume of the material is reduced, and finally the stability and weight limitation of the whole machine are ensured. The weight of the whole machine is 0.8kg at present, and the requirement below 1.5kg is met.
6. Key technology and solving approach
Calibrating the defocusing amount of the double detectors: the wide beam collimation beam is used as a target light source, and the accurate defocusing amount of the two area array detectors is calibrated through an angle measurement method.
The instruments needed for calibration are:
(1) Turntable with precision of +/-1 second
(2) Collimator with caliber larger than 35mm
The light inlet of the beam detection positioning instrument is placed on the center shaft of the working table surface of the turntable, and the collimator is aligned to the light inlet of the instrument. The light source of the collimator is turned on to emit parallel light, the posture of the beam detection positioning instrument is adjusted through the pitching adjusting knob of the table top of the turntable, the targets received by the two detectors are respectively positioned in the center of the view field of the beam detection positioning instrument, and when the turntable horizontally rotates, y-direction data of the beam detection positioning instrument are kept motionless. Recording current pixel positions (x 01, y 01) and (x 02, y 02) and a current angle value R0 of a turntable, namely an x initial position and a y initial position of a first area array detector 1, an x initial position and a y initial position of a second area array detector 2, rotating a turntable table surface to enable an imaging position to reach the left edge of a field of view, and recording imaging pixel positions (x 11, y 11) and (x 12, y 12) of two detectors of a light beam detection positioning instrument and a rotation angle position R1 of the turntable; then the table top of the turntable is rotated to translate the imaging position to the right edge of the field of view, the imaging pixel positions (x 21, y 21) and (x 22, y 22) of the two detectors of the beam detection positioner and the rotation angle position R2 of the turntable are recorded again, and the following formula is substituted
Where h is the displacement of the light spot measured on the array detector, d is the distance between the detector and the focal plane, f is the effective focal length of the collimator objective, and A is the angle.
h11 =x11-x 01 (offset of first area detector 1 in left field of view)
h12 =x12—x01 (offset of first area detector 1 in right field of view)
h21 =x21—x02 (offset of second area detector 2 in left field of view)
h22 =x22—x02 (offset of second area detector 2 in right field of view)
A1 =r1-R0 (angle value of turntable at left field of view)
A2 =r2-R0 (angle value of turntable at right field of view)
f=50mm is the effective focal length of the system
Substituting the measured value into a formula to calculate the actual offset of the detector from the focal plane.
7. Key component
(1) Collimation objective
The collimating objective 4 adopts an optimal shape lens, and has the best imaging effect on the collimated laser beam. For spherical lenses, a given focal length may be obtained from different combinations of radii of curvature for the front and back surfaces. Each combination of surfaces results in a different spherical error. The best profile lens will optimize the radius of curvature of each surface to achieve the minimum spherical error for infinite conjugation.
(2) Area array detector
The area array detector is used for receiving an optical target image of the system, and the upper computer collects the image gray matrix from the area array detector into the memory of the upper computer through the USB interface, so that any image processing algorithm can be performed on the upper computer. The area array detector generally comprises CCD, CMOS, PSD and the like, and the CMOS is selected as the detector.
CMOS is called complementary metal oxide semiconductor
(Complementary Metal-Oxide-Semiconductor, abbreviated as CMOS),
the design process of integrated circuit can produce basic elements of NMOS (n-type MOSFET) and PMOS (p-type MOSFET) on silicon wafer template for making static random access memory, microcontroller, microprocessor and other digital logic circuit system of computer electric appliance and its special technological characteristics are also used in optical instrument, for example CMOS image sensor is very common in some high-grade digital cameras.
(3) Light splitting prism
The beam-splitting prism 3 is a cubic beam-splitting prism, comprises a pair of accurate high-tolerance right-angle prisms, is glued together, is coated with a metal medium on the hypotenuse face of each prism, divides a beam of light in the horizontal direction into two directions, namely the horizontal direction and the vertical direction, and can generate different beam-splitting ratios according to different coating requirements.
The cube beam splitting prism is used for dividing a laser beam into two beams of light in an equal ratio, and the two beams of light are imaged on the two area array detectors respectively.
The size is as follows: 20mm by 20mm
Materials: N-BK7
Dimensional tolerances: 0/-0.1mm
Thickness tolerance: + -0.1mm
Angular tolerance: < 30
Spectral ratio: 50/50
Working wave band: 350 nm-1100 nm.
Advanced computer vision techniques and machine learning algorithms can be applied in the intelligent improvement of the above-described technical solutions and the detailed signal and data processing of the intelligent solutions. The following is an optimized implementation:
1) And the data acquisition and preprocessing module is used for: when the beam is incident on two area array detectors, the detectors convert the energy into electrical signals, which are recorded and converted into digitized data. Preprocessing includes noise filtering and baseline correction to improve data quality.
2) The light spot positioning module: the centroid position of the spot is detected and located using computer vision techniques such as edge detection and morphological operations. These operations may be performed on the images received by each detector to determine the exact location of the spot.
3) The angle and displacement calculation module: the angle and displacement of the beam are calculated using known geometric and optical principles. This involves complex mathematical models, including trigonometric calculations and inverse ray tracing.
4) Machine learning optimization module: machine learning algorithms, such as neural networks or support vector machines, are used to optimize the calculation of angles and displacements. This can be achieved by training a model to identify a particular spot pattern and corresponding angle and displacement, and then using this model to predict the angle and displacement of the beam in actual operation.
5) Feedback and correction module: the calculated angle and displacement are compared with the actual angle and displacement, and then corrected according to the difference. This involves adjusting the position of the detector or changing the direction of the beam.
6) And the intelligent decision module: based on the angle and displacement of the beam, the system may make decisions, such as adjusting the direction of the beam, changing system settings, or sending an alarm.
This process requires a lot of computational resources and precise hardware, but can improve the accuracy and reliability of beam positioning.
The following are two specific examples and specific embodiments thereof:
embodiment one:
in a beam detection positioner, the beam is first directed through a collimator objective lens and focused. Then, the converged light beam is split into two paths through the beam splitting prism, propagates in two directions respectively, and is converged into a minimum light spot at two focal plane positions. The two area array detectors are respectively arranged in front of and behind the two focal planes, can receive the energy of the dispersed light spots, and can measure the mass center positions of the two dispersed light spots. When the angle or displacement of the incident beam changes, the positions of the light spots received by the two area array detectors also change. By analyzing the change rule of the displacement of the two light spots, the angle and the displacement of the incident light beam can be accurately calculated.
1. Light beams emitted by the light source are converged through the collimating objective lens;
2. the beam splitting prism behind the collimating objective lens divides the converged light beam into two parts;
3. at the two focal plane positions, there is an area array detector;
4. when the angle or displacement of the incident light beam changes, the positions of the light spots received by the two area array detectors also change;
5. by analyzing the change rule of the displacement of the two light spots, the angle and the displacement of the incident light beam can be calculated.
Embodiment two:
the beam detection locator comprises two parts of hardware and software. The hardware part is made of aluminum alloy materials, and has low density, high strength, good mechanical property and corrosion resistance. The aluminum alloy after heat treatment is hollowed out, so that the total weight is reduced, and the stability of the whole machine is ensured. The software part is divided into three layers: bottom hardware control and data acquisition, middle data processing and transmission, upper data display and interactive operation. The software bottom layer adopts a plug-in loading mode, so that the hardware is easy to upgrade or change. In data processing, an original image is subjected to digital processing by adopting an image subdivision fitting means, and target characteristics are extracted to obtain the accurate sub-pixel position of the target.
1. Machining an aluminum alloy material to manufacture a hardware part;
2. through heat treatment and hollowed-out treatment, the weight of a hardware part is reduced, and the stability of the whole machine is ensured;
3. the software part is composed of three layers: the bottom layer is responsible for hardware control and data acquisition, the middle layer is responsible for data processing and transmission, and the upper layer is responsible for data display and interactive operation;
4. in the data processing process, an original image is processed by using an image subdivision fitting method, the characteristics of the target are extracted, and then the accurate sub-pixel position of the target is obtained.
The foregoing is merely illustrative of specific embodiments of the present invention, and the scope of the invention is not limited thereto, but any modifications, equivalents, improvements and alternatives falling within the spirit and principles of the present invention will be apparent to those skilled in the art within the scope of the present invention.