CN108106544B - Measurement system and measurement structure - Google Patents
Measurement system and measurement structure Download PDFInfo
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- CN108106544B CN108106544B CN201711448769.XA CN201711448769A CN108106544B CN 108106544 B CN108106544 B CN 108106544B CN 201711448769 A CN201711448769 A CN 201711448769A CN 108106544 B CN108106544 B CN 108106544B
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- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
Abstract
The invention relates to the technical field of laser, and provides a measuring system and a measuring structure. The measuring system comprises a cylindrical mirror device, an imaging device and an operation processing device, and can measure the beam width of a point-shaped beam emitted by a laser. During measurement, the connection line of the laser, the cylindrical mirror device and the imaging device is a straight line, and the operation processing device is connected with the imaging device. After the point-like light beam emitted by the laser enters the cylindrical mirror device, the cylindrical mirror device spreads the point-like light beam into a strip-like light beam, and the strip-like light beam is emitted to the imaging device, and the width of the strip-like light beam is the same as that of the point-like light beam. After the imaging device generates an imaging signal corresponding to the strip-shaped light beam, the arithmetic processing device acquires the imaging signal from the imaging device and calculates and obtains the beam width of the strip-shaped light beam based on the imaging signal. The beam width can be used to guide the adjustment of the straightness of the laser beam. The measuring system has high measuring precision, simple and quick measuring process and no need of manual intervention.
Description
Technical Field
The invention relates to the technical field of laser, in particular to a measuring system and a measuring structure.
Background
The laser has the characteristics of high brightness, strong directivity, good monochromaticity, strong coherence and the like, and is widely applied to the aspects of engineering, measurement, medical treatment and the like. In the fields of precision instrument manufacturing and detection, large-size measurement, large-size instrument installation and positioning, military industry product manufacturing and the like, the laser is used as a core light source, for example: laser thickness gauges, for the product quality of assurance, often need the laser instrument to provide the horizontal, vertical datum line of higher accuracy. Therefore, within a specified action interval, the straightness of the laser beam plays a crucial role. It is considered that the straightness of the laser beam is best when the spot size of the laser beam is smaller and the spot size of the laser beam is symmetrically spindle-shaped in the action zone. In the prior art, the method for adjusting the straightness of the laser beam mainly guides adjustment by directly observing the spot size of the laser beam in an action area through naked eyes, the process is time-consuming and labor-consuming, the accuracy cannot be guaranteed, and human eyes can be possibly injured.
Disclosure of Invention
In view of the above, embodiments of the present invention provide a measurement system and a measurement structure to solve the above technical problems.
In order to achieve the purpose, the invention provides the following technical scheme:
in a first aspect, an embodiment of the present invention provides a measurement system for measuring a beam width of a spot beam emitted by a laser, including: a cylindrical mirror device, an imaging device and an arithmetic processing device;
the connection line of the laser, the cylindrical mirror device and the imaging device is a straight line, and the operation processing device is connected with the imaging device;
after the point light beam enters the cylindrical mirror device, the cylindrical mirror device expands the point light beam into a strip light beam and enables the strip light beam to be emitted to the imaging device, wherein the width of the strip light beam is the same as that of the point light beam;
after the imaging device generates an imaging signal corresponding to the strip-shaped light beam, the arithmetic processing device acquires the imaging signal from the imaging device and calculates and obtains the beam width of the strip-shaped light beam based on the imaging signal.
Optionally, the cylindrical mirror device includes: a first cylindrical mirror and a second cylindrical mirror;
the first cylindrical mirror and the second cylindrical mirror are arranged in parallel at a preset interval so that the focus of the first cylindrical mirror and the focus of the second cylindrical mirror are superposed with each other;
after the point-like light beam enters the first cylindrical mirror, the point-like light beam is unfolded into a strip-like light beam after sequentially passing through the first cylindrical mirror and the second cylindrical mirror, and the strip-like light beam is emitted from the second cylindrical mirror to the imaging device.
Optionally, the cylindrical mirror device includes: an outer cylinder and an inner cylinder;
a second cylindrical mirror is arranged at the first end of the outer cylinder, a first cylindrical mirror is arranged at the first end of the inner cylinder, a second end, different from the first end, of the outer cylinder is sleeved on the peripheral surface of the first end of the inner cylinder, and the point-shaped light beams are incident to the first cylindrical mirror from the second end, different from the first end, of the inner cylinder;
the distance between the first cylindrical mirror and the second cylindrical mirror can be adjusted to a predetermined interval by sliding the inner peripheral surface of the first end of the outer cylinder on the outer peripheral surface of the first end of the inner cylinder.
Optionally, the first end of the outer barrel is provided with a locking screw.
Optionally, the imaging device includes a light screen, an imaging lens, and an image sensor;
after the strip-shaped light beams are incident to the light screen, rectangular light bars are formed on the light screen, and the width of each rectangular light bar is the same as that of each strip-shaped light beam; the transmission image of the rectangular light bar is focused by the imaging lens to be imaged on the image sensor, and the image sensor can generate an imaging signal corresponding to an imaging result.
Optionally, the optical screen includes: the optical attenuator comprises an optical attenuator sheet and a sulfuric acid paper film, wherein the sulfuric acid paper film is attached to the surface of the optical attenuator sheet.
Optionally, the imaging device further comprises: the lens hood, the light screen, the imaging lens and the image sensor are all arranged in the lens hood.
Optionally, the arithmetic processing unit includes: a signal processor and a terminal device;
the signal processor is respectively connected with the image sensor and the terminal equipment, acquires an imaging signal from the image sensor and sends at least two position count values for representing the width of the imaging signal to the terminal equipment, wherein each position count value in the at least two position count values corresponds to one position on the image sensor;
the terminal device obtains the width of the rectangular light bar by calculation based on at least two position count values.
Optionally, the measurement system further includes: the laser device is matched with the sliding rail in a sliding mode, so that the laser device can move freely on a connecting line of the cylindrical mirror device and the imaging device.
In a second aspect, an embodiment of the present invention provides a measurement structure, including: the measuring system and the laser, the cylindrical mirror device of the measuring system and the imaging device of the measuring system are connected in a straight line, and the operation processing device of the measuring system is connected with the imaging device.
The invention has the following beneficial effects: the measuring system provided by the embodiment of the invention can measure the beam width of a point-shaped beam emitted by a laser, and comprises a cylindrical mirror device, an imaging device and an operation processing device. The laser, the cylindrical mirror device and the imaging device are connected in a straight line, and the operation processing device is connected with the imaging device. When measuring, firstly, the laser is opened to enable the laser to emit point-shaped light beams, the point-shaped light beams are unfolded into strip-shaped light beams by the cylindrical mirror device and emitted to the imaging device after being incident to the cylindrical mirror device, the strip-shaped light beams generate imaging signals corresponding to the strip-shaped light beams in the imaging device, the operation processing device obtains the imaging signals from the imaging device, and the light beam width of the strip-shaped light beams is obtained through calculation based on the imaging signals. The width of the strip-shaped light beam generated by the point light beam through the cylindrical mirror device is the same as that of the point light beam, so that the operation processing device measures the width of the obtained point light beam. The beam width can be used as a main basis for guiding laser beam straightness adjustment, so that a user of the laser can complete laser straightness adjustment on the basis. The measurement process is automatically completed, manual intervention is not needed, the measurement efficiency is high, and the human eyes cannot be injured. Meanwhile, the beam width obtained by measurement of the measuring system can reflect the spot size of the laser beam, and compared with a mode of determining the spot size by naked eyes in the prior art, the accuracy is obviously improved, so that the straightness adjustment of the laser beam can be guided more effectively.
In order to make the above objects, technical solutions and advantages of the present invention more comprehensible, embodiments accompanied with figures are described in detail below.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.
FIG. 1 is a schematic diagram showing a criterion for adjusting straightness of a laser beam;
FIG. 2 is a schematic structural diagram of a measurement structure provided by an embodiment of the invention;
fig. 3 is a schematic structural diagram of a cylindrical mirror device provided in an embodiment of the present invention;
FIG. 4 is a schematic diagram of a rectangular light bar on a light screen provided by an embodiment of the present invention;
FIG. 5 is a schematic diagram showing the object-image relationship of an imaging apparatus provided by an embodiment of the present invention;
fig. 6 is a schematic diagram illustrating a process of acquiring a position count value of a signal processor according to an embodiment of the present invention.
In the figure: 1-measuring the structure; 10-a cylindrical mirror device; 100-a first cylindrical mirror; 110-a second cylindrical mirror; 120-outer cylinder; 122-locking screws; 130-an inner cylinder; 20-an imaging device; 200-a light screen; 210-an imaging lens; 220-an image sensor; 300-a signal processor; 310-a terminal device; 30-an arithmetic processing device; 40-a slide rail; 50-a laser; 500-a laser body; 510-a laser head; 502-a focusing lens; 504-locking ring.
Detailed Description
In the prior art, the straightness of the laser beam is generally adjusted by a human eye recognition method. The method comprises the steps of placing an optical screen on an optical path of a laser beam, forming light spots on the optical screen, enabling human eyes to observe the sizes of the light spots, and adjusting a focusing lens of a laser device based on the sizes of the light spots so that the laser beam meets the adjustment standard of the straightness of the beam in a specified action interval. Fig. 1 shows a schematic diagram of the adjustment criteria for the straightness of the laser beam. Referring to fig. 1, OO 'is an action interval of the laser, which is generally determined according to a practical application scenario of the laser, and in the action interval, a direction of the laser beam is from a point O to a point O'. The light screen is respectively placed at the midpoint of OO ', at the point O ' and at the point O ', the size of a light spot on the light screen is obtained through visual observation, the light spot is generally circular or approximately circular, the width of the light spot can be defined as the size of the light spot, the sizes of light spots are respectively obtained at the three positions as CC ', AA' and BB ', the focusing lens of the laser is adjusted to ensure that the waist spot size CC' at the midpoint of the action section is as small as possible, the light spot sizes AA 'and BB' at the two end points of the action section are as same as possible, that is, the spot size of the laser beam is distributed in a symmetrical spindle shape in the action zone, and at this time, in the process of the laser beam from the point O to the point O', the spot size of the laser beam is unchanged, and the laser beam and the parallel beam are not distinguished from each other at two end points of the action section, so that the straightness of the beam is considered to be the best at the moment. It should be noted that the above-mentioned adjustment process is not completed in one time, and may require moving the light screen repeatedly for many times and observing continuously to obtain a satisfactory adjustment result.
The inventor finds that the human eye identification method in the prior art has at least the following defects through long-term research: firstly, the laser emitted by the multispectral laser is not necessarily in the visible light band, and the size of the light spot formed by the multispectral laser cannot be observed by human eyes; secondly, the power of part of the laser is high, and visual damage can be caused by the fact that human eyes directly observe light spots for a long time; thirdly, the human eye identification method does not quantify the absolute size of the measured light spot, but only approximately judges the relative size of the light spot, has poor accuracy and is only suitable for application scenes with low requirement on the straightness of the light beam. For example, in FIG. 1, when the light screen is at the midpoint of OO', the laser is adjusted while observing the size of the spot on the light screen until the spot size is adjusted to the minimum that the human eye sees, obviously this "minimum" depends on the judgment of the moderator himself, with higher artifacts; fourthly, due to inaccuracy of manual adjustment, when the requirement on straightness of the laser beam is high, the laser beam needs to be adjusted repeatedly to meet the requirement, and time and labor are wasted. In view of the above, embodiments of the present invention provide a measurement system and a measurement structure to measure the spot size of a laser beam quickly and accurately, so as to improve the above technical problems.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.
Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.
In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of the embodiments of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
Fig. 2 shows a schematic structural diagram of a measurement structure 1 provided in an embodiment of the present invention. Referring to fig. 2, the measurement structure 1 includes a laser 50 and a measurement system provided by an embodiment of the present invention. The laser 50 includes a laser body 500 and a laser head 510, and the laser body 500 generates laser light and emits a laser beam from the laser head 510. The laser head 510 is provided with a focusing lens 502 and a locking ring 504, the focusing lens 502 is used for adjusting laser beams so that the size of light spots formed by the laser beams meets the standard of straightness of the light beams, and the locking ring 504 is used for locking the focusing lens 502 after the adjustment is completed so that the focusing lens cannot be freely adjusted. The measuring system comprises a cylindrical mirror device 10, an imaging device 20 and an operation processing device 30, wherein a laser 50, the cylindrical mirror device 10 and the imaging device 20 are arranged on a straight line, a laser beam passes through the straight line, and the operation processing device 30 is connected with the imaging device 20. As an alternative implementation manner, the measuring system in the embodiment of the present invention further includes a slide rail 40, the laser 50 is disposed on the slide rail 40 and can freely move along the straight line where the slide rail 40 is located, and a scale (not shown) is disposed on the slide rail 40 to facilitate recording the position of the laser 50 when adjusting the straightness of the laser beam.
The basic workflow of the measuring system is as follows: after the laser 50 is fixed at a specific position on the slide rail 40, the laser 50 is turned on to generate a laser beam. The cross section of the laser beam is circular or approximately circular, for convenience of explanation, the laser beam is called as a point beam, the cross section of the point beam is actually a light spot formed on the surface of an object by the beam when the beam irradiates the surface of the object, the beam width is defined as the width of the cross section of the beam, obviously, the beam width of the point beam can represent the size of the light spot formed by the point beam, and thus, the beam width of the point beam is measured to be equal to the size of the light spot formed by the point beam, and the straightness of the point beam in an action interval can be adjusted according to the beam width of the point beam. The spot beam is emitted from the laser head 510 of the laser 50 and then enters the cylindrical mirror device 10, the cylindrical mirror device 10 spreads the spot beam into a strip beam, and the strip beam is emitted to the imaging device 20, wherein the strip beam is a beam having a rectangular cross section, and the beam width of the strip beam is the same as the beam width of the spot beam, so that measuring the width of the spot beam can be converted into measuring the width of the strip beam. The strip beam is imaged in the imaging device 20 and generates an imaging signal corresponding to the imaging signal, and the arithmetic processing device 30 acquires the imaging signal from the imaging device 20 and obtains the beam width of the strip beam by calculation based on the imaging signal, that is, the beam width of the spot beam generated by the laser 50 at a specific position of the slide rail 40 is obtained at the same time. Thus, the laser 50 can be moved to different positions on the slide rail 40, and the straightness of the laser beam can be adjusted according to the beam width measured at each position, and the specific adjustment mode will be described later.
Fig. 3 is a schematic structural diagram of a cylindrical mirror device 10 according to an embodiment of the present invention. Referring to fig. 3, the cylindrical mirror device 10 includes a first cylindrical mirror 100 and a second cylindrical mirror 110, and both the first cylindrical mirror 100 and the second cylindrical mirror 110 are plano-convex cylindrical mirrors. First and second cylindrical mirrors 100 and 110 the first and second cylindrical mirrors 100 and 110 are disposed in parallel at a predetermined interval so that the focal point of the first cylindrical mirror 100 and the focal point of the second cylindrical mirror 110 coincide with each other. At this time, the spot beam enters the first cylindrical mirror 100, passes through the first cylindrical mirror 100 and the second cylindrical mirror 110 in sequence, is expanded into a stripe beam, and exits from the second cylindrical mirror 110 to the imaging device 20. The cross section of the strip-shaped light beam is a rectangle, the width of the rectangle is the same as the width of the spot-shaped light beam, and the height of the rectangle depends on the distance between the first cylindrical mirror 100 and the second cylindrical mirror 110. In practice, however, the focal positions of the first cylindrical mirror 100 and the second cylindrical mirror 110 may not be accurately known, and as an alternative embodiment, the cylindrical mirror system further includes an outer cylinder 120 and an inner cylinder 130. The first cylindrical mirror 100 is disposed at a first end of the inner cylinder 130, the second cylindrical mirror 110 is disposed at a first end of the outer cylinder 120, a second end of the outer cylinder 120 different from the first end is sleeved on an outer peripheral surface of the first end of the inner cylinder 130, and the point-like light beam enters the first cylindrical mirror 100 from the second end of the inner cylinder 130 different from the first end, and exits from the second cylindrical mirror 110 to the imaging device 20 after being unfolded into a strip-like light beam by the first cylindrical mirror 100 and the second cylindrical mirror 110. The inner circumferential surface of the first end of the outer cylinder 120 can slide on the outer circumferential surface of the first end of the inner cylinder 130, so as to adjust the distance between the first cylindrical mirror 100 and the second cylindrical mirror 110, the light screen 200 is arranged in the imaging system, the strip-shaped light beams irradiate on the light screen 200 to form a rectangular light bar, the relative position between the outer cylinder 120 and the inner cylinder 130 of the cylindrical mirror device 10 is adjusted, the height of the rectangular light bar is correspondingly changed, in practice, the rectangular light bar can be adjusted to be completely displayed on the light screen 200 in the imaging system, and at this time, the focuses of the first cylindrical mirror 100 and the second cylindrical mirror 110 coincide or approximately coincide. The outer cylinder 120 is further provided with a locking screw 122, and after the relative position of the outer cylinder 120 and the inner cylinder 130 is adjusted, the relative position of the outer cylinder 120 and the inner cylinder 130 can be locked by the locking screw 122 to avoid sliding.
With continued reference to fig. 2, the imaging device 20 includes a light screen 200, an imaging lens 210, and an image sensor 220. As an alternative implementation manner of the embodiment of the present invention, the imaging device 20 may further include a light shield (not shown), the light screen 200, the imaging lens 210, and the image sensor 220 are disposed in the light shield, and only one surface of the light screen 200 is exposed out of the light shield for receiving the incident strip light beam, and the light shield may avoid the influence of natural light on the imaging device 20, so that the measurement result is more accurate. As mentioned above, after the light beam is incident on the light screen 200, a rectangular light bar is formed on the light screen 200, the rectangular light bar can be regarded as a section of the light beam, the width of the rectangular light bar is the same as the width of the light beam, and the height of the rectangular light bar is determined by the distance between the first cylindrical mirror 100 and the second cylindrical mirror 110, and in fig. 2, the rectangular light bar on the light screen 200 is shown in diagonal hatching. Obviously, after the point-like light beam is expanded into the strip-like light beam, the cross-sectional area of the light beam is significantly increased, the energy per unit area is significantly reduced, and even if human eyes look straight at the rectangular light bar, human eyes generally do not cause damage, and generally speaking, in the remeasurement process, as long as the rectangular light bar can be completely displayed in the light screen 200, human eyes do not need to observe the rectangular light bar. In addition, the rectangular light bar is characterized in that at any height position in the height direction, the energy distribution in the width direction is the same as the energy distribution law of the spot-like light beam in the width direction. Fig. 4 is a schematic diagram of a rectangular light bar on a light screen 200 according to an embodiment of the present invention. Referring to fig. 4, if a cylindrical mirror system is not used, the spot beam forms a circular light spot on the light screen 200, and if a cylindrical mirror system is used, the strip beam forms a rectangular light bar on the light screen 200, the widths of the circular light spot and the rectangular light bar are the same, and the energy distribution at any position in the height direction of the rectangular light bar, for example, at BB ' and CC ' positions is the same as the energy distribution rule at AA ' position of the circular light spot (referring to the energy distribution in the width direction), that is, the energy distribution in the width direction of the spot beam to be measured can be converted into the energy distribution in the width direction of the rectangular light bar at any height position. For a point-shaped beam, in an optimal case, the energy of the light spot in the width direction is symmetrically distributed, is highest in the center and gradually decreases towards two sides, such as a Gaussian distribution. However, in practice, the energy of the spot beam generated by the laser 50 in the width direction may not be strictly symmetrically distributed in the above manner, and the distribution of the energy of the spot beam is an important factor affecting the performance of the laser 50, and may be measured together when the width of the spot beam is measured, and used as an index for evaluating the performance of the laser 50.
The light screen 200 is made of a low-transmittance medium, and in an alternative implementation manner of the embodiment of the present invention, the light screen 200 is formed by laminating an optical attenuation sheet and a sulfuric acid paper film, and the strip-shaped light beams form rectangular light strips on the sulfuric acid paper film through the optical attenuation sheet. The diffuse reflection effect and the transmission effect of the sulfuric acid paper film are good, a user can conveniently observe the rectangular light strip, and meanwhile, the rectangular light strip can also penetrate through the sulfuric acid paper film to form a transmission image. With continued reference to fig. 2, the transmission image of the rectangular light bar is focused by the imaging lens 210 and imaged on the image sensor 220, and the image sensor 220 performs photoelectric conversion to generate an imaging signal corresponding to the imaging result. The image sensor 220 may be a CCD image sensor, a CMOS image sensor, or the like, in fig. 2, the image sensor 220 is a long strip and is mounted on an imaging plate, a rectangular light bar is imaged on the imaging plate, the imaged image is crossed with the image sensor 220, and in fig. 2, the image of the rectangular light bar is shown by diagonal hatching. Taking a CCD image sensor as an example, the saturated exposure of a commonly used linear CCD image sensor is less than 0.51x · s, and if the intensity of light irradiated on the surface of the CCD image sensor is too high, the CCD image sensor will be saturated, the sensitivity and accuracy of photoelectric conversion will be greatly reduced, and the quality of the generated imaging signal will be degraded. In the embodiment of the present invention, the rectangular light bar is attenuated by the low transmittance light screen 200, the illumination intensity of the rectangular light bar is greatly reduced, and the energy per unit area of the rectangular light bar is substantially lower than the energy per unit area of the circular light spot, so that actually, in the embodiment of the present invention, the illumination intensity received by the CCD image sensor is not large, and the CCD image sensor cannot reach saturation. In addition, it is mentioned before that the image of the rectangular light bar crosses the image sensor 220 in a cross manner, that is, only a part of the image of the rectangular light bar is on the image sensor 220, but as the image of the rectangular light bar, the shape of the image of the rectangular light bar is obviously also a rectangle, and the width of the image of the rectangular light bar at any position is the same, according to the previous analysis, the energy distribution of any height position of the rectangular light bar in the width direction is the same as the energy distribution rule of the spot-shaped light beam in the width direction, and the imaging lens 210 does not change the energy distribution rule of the rectangular light bar, so that the energy distribution of any height position of the image of the rectangular light bar in the width direction is the same as the energy distribution rule of the spot-shaped light. Therefore, the imaging signal generated on the image sensor 220 can already represent all the characteristics of the imaging result of the rectangular light bar, and it is only necessary to measure the characteristics of the imaging signal in the arithmetic processing device 30 and convert the characteristics of the imaging signal into the width of the rectangular light bar and the energy distribution in the width direction according to the lens imaging rule. Obviously, another benefit of using a cylindrical mirror system to spread the point beam into a strip beam is: the placement position of the image sensor 220 does not need to be controlled to be too accurate, and the image sensor can be ensured to be crossed with the image cross of the rectangular light bar without influencing the calculation result of a subsequent operation processing system.
FIG. 5 is a schematic diagram showing an object-image relationship OF the imaging device 20 according to an embodiment OF the present invention, where FIG. 5 is a top view OF the imaging device 20, FIG. 4 shows X1X2 as a light screen 200, X3X4 as an image sensor 220, a point O is a center OF the imaging lens 210, a point O1 is an intersection point OF an optical axis and the light screen 200, a point O2 is an intersection point OF the optical axis and the image sensor 220, θ 1 is an angle between an object plane OF the light screen 200 and the optical axis, θ 2 is an angle between an image plane OF the image sensor 220 and the optical axis, O1H is an object width M, O2H ' is an image width N, OF is an object focal length f, OF ' is an image focal length f ', L0Is H point object distance, namely HO, &lTtT translation = 'L' &gTt L &lTt/T &gTt0For 'H' dot image distance, H 'O, distance L2 of OO1 is L' and β is homeotropic magnification.
Derived from equations (1) and (2):
simplifying formula (4) and bringing formula (1) into:
f'cosθ1·M+sinθ2cosθ1·MN+(f'-L)sinθ2·N＝0
when the optical system is fixed, the parameters L, f', θ 1, and θ 2 are all fixed constants, and the constants a, b, and c are as follows:
a＝f'cosθ1；
b＝sinθ2cosθ1
c＝(f'-L)sinθ2
the following can be obtained:
aM+bMN+cN＝0 (5)
equation (5) can obtain a, b, and c by the least square method, so that the width of the rectangular light bar:
obviously, as can be seen from equations (5) and (6), the width of the rectangular light bar is directly related to the width of the image of the rectangular light bar on the image sensor 220, and is independent of the projection position of the rectangular light bar on the light screen 200 and the projection position of the image of the rectangular light bar on the image sensor 220. On the image sensor 220, the object points and the image points are in one-to-one correspondence, assuming that the object point range is X1X2, and the image point range is X3X4, then the point X1 and the point X3 are the relative starting zero points of the object and the image, respectively, in fig. 5, O1X1 is s, O1H is M, HX1 is y, and M is y + s; O2X3 ═ t, O2H ═ N, H' X3 ═ X, and N ═ X + t can be obtained. The tape-in (6) can be obtained:
the expansion of equation (7) into a series can be obtained:
y＝a0+a1x+a2x2+a3x3+… (8)
in the paraxial ray of an ideal optical imaging system, equation (8) can be expressed approximately as:
y＝a1x2+b1x+c1(9)
that is, the position y of any object point H in the rectangular light bar relative to X1 can be calculated by the position X of the image point H' corresponding to the object point H in the image of the rectangular light bar relative to X3.
With continued reference to fig. 2, the arithmetic processing device 30 includes a signal processor 300 and a terminal device 310, and the signal processor 300 is connected to the image sensor 220 and the terminal device 310, respectively. The signal processor 300 mainly includes a single chip, an a/D conversion chip, an external memory, and a peripheral interface circuit, and mainly functions to generate a working clock signal for driving the image sensor 220, obtain an imaging signal generated by the image sensor 220, and obtain a plurality of position count values and corresponding voltage values in the imaging signal. Wherein the position count value is used to represent the positions of the image of the rectangular light bar on the image sensor 220, and the voltage count value is used to represent the illumination intensity of the image of the rectangular light bar at the positions, as shown in table 1:
TABLE 1
The position count value x is the position x in equation (9). Fig. 6 is a schematic diagram illustrating a process of acquiring a position count value of the signal processor 300 according to an embodiment of the present invention. Referring to fig. 6, the horizontal axis of fig. 6 is a position count value, the vertical axis is a voltage value after a/D conversion, the dots in fig. 6 are the result of plotting the position count value and the corresponding voltage value of each position in table 1, and a curve formed by connecting the dots can be approximately regarded as an imaging signal. As can be seen, in the signal processor 300, the imaging signal is quantized sampled to obtain a plurality of position count values and corresponding voltage values. The signal processor 300 can reasonably set the comparison level, and the part of the imaging signal with the voltage value at or above the comparison level is used as an effective signal, and the part below the comparison level is used as an ineffective signal (such as noise), so that at least two position count values for representing the width of the imaging signal can be obtained. For example, in fig. 6, the comparison level v is taken to be 90, and the leading edge position count value x1 is obtained to be 18150 and the trailing edge position count value x2 is obtained to be 18010 of the imaging signal. Meanwhile, in order to measure the energy distribution of the rectangular light bar, the transverse geometric center position count value x3 ═ x1+ x2)/2 ═ 18080 and the transverse geometric center position count value can also be obtained
Here, the horizontal direction is a width direction of the rectangular light bar or the image of the rectangular light bar. The four position count values may be sent to the terminal device 310 to calculate the width of the rectangular light bar and the energy distribution. According to equation (9), the terminal device 310 first obtains the parameters a1, b1, c1 before performing the calculation. The specific calculation method is shown in table 2:
TABLE 2
Before the formal measurement is started, the rectangular light bar is adjusted to enable specific positions, such as the center positions, of the rectangular light bar to be located at 0um, 6000um,.. and 30000um respectively, position count values 27609, 23184,.. and 3399 corresponding to the positions in the imaging signals are obtained on the signal processor 300 and are sent to the terminal device 310, and the parameters a1, b1 and c1 are solved on the terminal device 310 in an expression (9) mode. The three groups of data of serial numbers 1, 2 and 3 can solve a group of a1, b1 and c1 to obtain y-3E-06 x ^ 2-1.1826 x +35251, the condition of using the expression is that 27609 is not more than x < 23184, that is to say, when calculating y, firstly judging whether the value of x is in the range, and if yes, calculating by using the expression of y. By analogy, six groups of data of the sequence numbers 1 to 6 can obtain four expressions of y, the value ranges of x corresponding to the expressions are different, and the four expressions of y and the corresponding value ranges of x are stored on the terminal device 310. When the terminal device 310 receives the x1, x2, x3, and x4 sent by the signal processor 300, the above expressions and value ranges can be used for calculation, as shown in table 3:
| location count value name | Value x | Light strip position y (um) |
| Leading edge position count value | x1＝18150 | y＝1E-06x2-1.2447x+34723＝12461 |
| Trailing edge position count value | x2＝18010 | y＝1E-06x2-1.2447x+34723＝12630 |
| Transverse geometric center position count value | x3＝18080 | y＝1E-06x2-1.2447x+34723＝12545.7 |
| Transverse geometric center of gravity position count | X4＝18082 | y＝1E-06x2-1.2447x+34723＝12543.3 |
TABLE 3
The method for calculating the width of the rectangular light bar is only one example, and the method does not represent that the width of the rectangular light bar can be calculated only by using the above method and the above formula, so that the protection range of the invention is not limited, in the embodiment of the invention, the signal processor 300 of the calculation processing device 30 can adopt a signal processing unit used by a laser thickness gauge of limited original photoelectric measurement and control technology in Henan, the model number is JGC-H1-C L B, the terminal device 310 can adopt a single chip microcomputer system and electronic equipment, the terminal device 310 can adopt a single chip microcomputer system and 1B-C L B, the energy value and the central position of the rectangular light bar in Henan, and the central position of the rectangular light bar can be calculated, the beam width of the rectangular light bar can be obtained, namely the beam width of the dot-shaped light beam is obtained, the central position of the light bar is 12545.7um, the central position of the light bar is 12543.4 um., the central position of the light bar is not completely coincided with the central position of the light bar, and the energy distribution of the dot-shaped light beam is not completely distributed in the beam direction of the light bar, so that the light bar is not completely distributed symmetrically distributed in the beam width direction of the light bar, so that the light bar is obtained, so that the light bar.
In the measurement system provided by the embodiment of the present invention, the straightness of the laser beam is adjusted by moving the laser 50 on the slide rail 40. For example, the straightness of the laser beam in the working range of 1m to 2m is adjusted, and the adjustment criteria are the same as those shown in fig. 1. The laser 50 is moved to the positions 1m, 1.5m and 2m away from the light screen 200 respectively (positioning is performed through a scale on the slide rail 40), the light beam width reading at the moment is obtained in real time through the terminal device 310, the focusing lens 502 of the laser 50 is adjusted to enable the light beam width reading at the position 1.5m to be as small as possible, and the light beam width reading at the positions 1m and 2m to be as same as possible, namely the width of the laser beam is symmetrically distributed in a spindle shape in an action interval, at this moment, the adjustment is completed, and the locking ring 504 of the laser 50 is locked. It should be noted that the above adjustment process is not completed in one time, and the laser 50 may need to be moved repeatedly for many times, but since the terminal device 310 can calculate the beam width in real time and display the reading in real time, the user can quickly determine the adjustment result, so that the adjustment efficiency of the laser beam straightness is greatly improved.
In summary, the measurement system and the measurement structure 1 provided in the embodiment of the present invention can accurately measure the width of the laser beam generated by the laser 50 in a quantitative manner, and the measurement speed is fast, which is helpful for a user to quickly complete the adjustment of the straightness of the laser beam on the basis. Meanwhile, in the measurement process, a user does not need to observe the laser beam for a long time, so that visual damage can be avoided, the measurement process is automatically completed by the measurement system, the wavelength of the light emitted by the laser 50 does not influence the measurement result, and the laser with the invisible wavelength can also be used for measurement. In addition, the measurement system and the measurement structure 1 provided by the present invention can also measure the energy distribution of the laser beam, and facilitate the user to judge the performance of the laser 50 while adjusting the straightness of the beam.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (8)
1. A measurement system for measuring a beam width of a spot beam emitted by a laser, comprising: a cylindrical mirror device, an imaging device and an arithmetic processing device;
the connection line of the laser, the cylindrical mirror device and the imaging device is a straight line, and the operation processing device is connected with the imaging device;
after the point-shaped light beam enters the cylindrical mirror device, the cylindrical mirror device expands the point-shaped light beam into a strip-shaped light beam, and the strip-shaped light beam is emitted to the imaging device, wherein the width of the strip-shaped light beam is the same as that of the point-shaped light beam;
after the imaging device generates an imaging signal corresponding to the strip-shaped light beam, the operation processing device acquires the imaging signal from the imaging device and calculates and obtains the light beam width of the strip-shaped light beam based on the imaging signal;
the imaging device comprises a light screen, an imaging lens and an image sensor;
after the strip-shaped light beams are incident to the light screen, rectangular light bars are formed on the light screen, and the width of each rectangular light bar is the same as that of each strip-shaped light beam; the transmission image of the rectangular light bar is focused on the image sensor through the imaging lens to be imaged, and the image sensor can generate the imaging signal corresponding to the imaging result;
the arithmetic processing device includes: a signal processor and a terminal device;
the signal processor is respectively connected with the image sensor and the terminal equipment, acquires the imaging signal from the image sensor and sends at least two position count values for representing the width of the imaging signal to the terminal equipment, wherein each position count value of the at least two position count values corresponds to one position on the image sensor;
and the terminal equipment calculates and obtains the width of the rectangular light bar based on the at least two position count values.
2. The measurement system of claim 1, wherein the cylindrical mirror arrangement comprises: a first cylindrical mirror and a second cylindrical mirror;
the first cylindrical mirror and the second cylindrical mirror are arranged in parallel at a preset interval so that the focus of the first cylindrical mirror and the focus of the second cylindrical mirror are superposed with each other;
after the point-like light beam enters the first cylindrical mirror, the point-like light beam is unfolded into a strip-like light beam after sequentially passing through the first cylindrical mirror and the second cylindrical mirror, and the strip-like light beam is emitted from the second cylindrical mirror to the imaging device.
3. The measurement system of claim 2, wherein the cylindrical mirror arrangement comprises: an outer cylinder and an inner cylinder;
the first end of the outer cylinder is provided with the second cylindrical mirror, the first end of the inner cylinder is provided with the first cylindrical mirror, the second end, different from the first end, of the outer cylinder is sleeved on the outer peripheral surface of the first end of the inner cylinder, and the point-shaped light beams are incident to the first cylindrical mirror from the second end, different from the first end, of the inner cylinder;
the distance between the first cylindrical mirror and the second cylindrical mirror can be adjusted to the preset interval by sliding the inner circumferential surface of the first end of the outer cylinder on the outer circumferential surface of the first end of the inner cylinder.
4. A measuring system according to claim 3, wherein the first end of the outer barrel is provided with a locking screw.
5. The measurement system of any of claims 1-4, wherein the optical screen comprises: the optical attenuation sheet comprises an optical attenuation sheet and a sulfuric acid paper film, wherein the sulfuric acid paper film is attached to the surface of the optical attenuation sheet.
6. The measurement system of claim 5, wherein the imaging device further comprises: and the light screen, the imaging lens and the image sensor are all arranged in the light shield.
7. The measurement system of any one of claims 1-4, further comprising: the laser device is matched with the sliding rail in a sliding mode, so that the laser device can move freely on a connecting line of the cylindrical mirror device and the imaging device.
8. A measurement structure, comprising: the measuring system and the laser according to any one of claims 1 to 7, wherein a line connecting the laser, the cylindrical mirror device of the measuring system and the imaging device of the measuring system is a straight line, and the arithmetic processing device of the measuring system is connected with the imaging device.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101126313B1 (en) * | 2011-10-14 | 2012-03-22 | 인타스(주) | Led lighting having deflection construction |
| CN103235300A (en) * | 2013-04-26 | 2013-08-07 | 中国科学院上海光学精密机械研究所 | Astigmatism Fourier transform-based optical synthetic aperture laser imaging radar processor |
| CN105750729A (en) * | 2016-05-03 | 2016-07-13 | 长春理工大学 | Laser processing device with linear array optical lens assembly with micro cylindrical lenses in cylindrical distribution |
| CN106569331A (en) * | 2016-11-17 | 2017-04-19 | 上海无线电设备研究所 | Laser leading beacon optical system |
| CN207741694U (en) * | 2017-12-27 | 2018-08-17 | 河南中原光电测控技术有限公司 | Measuring system and measurement structure |
-
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101126313B1 (en) * | 2011-10-14 | 2012-03-22 | 인타스(주) | Led lighting having deflection construction |
| CN103235300A (en) * | 2013-04-26 | 2013-08-07 | 中国科学院上海光学精密机械研究所 | Astigmatism Fourier transform-based optical synthetic aperture laser imaging radar processor |
| CN105750729A (en) * | 2016-05-03 | 2016-07-13 | 长春理工大学 | Laser processing device with linear array optical lens assembly with micro cylindrical lenses in cylindrical distribution |
| CN106569331A (en) * | 2016-11-17 | 2017-04-19 | 上海无线电设备研究所 | Laser leading beacon optical system |
| CN207741694U (en) * | 2017-12-27 | 2018-08-17 | 河南中原光电测控技术有限公司 | Measuring system and measurement structure |
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