Three dimensional shape measurement system and method based on the scanning ranging of double light combs
Technical field
The invention belongs to measuring three-dimensional morphology technical fields, and in particular to a kind of three-dimensional shaped based on the scanning ranging of double light combs
Looks measuring system and method.
Background technique
Measuring three-dimensional morphology technology is widely used in the fields such as installation, defects detection, reverse-engineering in manufacturing industry, existing
Measuring three-dimensional morphology technology mainly has scan-type three-dimensional measurement scheme and stares three-dimensional measurement scheme.Measurement is stared because of measurement
Area and the depth of field are limited, and one-dimensional measurement precision is also not high enough, also need in certain accurate topography measurements using scan-type three-dimensional
Measurement.And scan-type three-dimensional measurement scheme is probably divided into increment measurement and absolute measurement.Interference pattern based on increment measurement
Mensuration is not suitable for measurement with the violent measured object of this change in optical path length of cascaded surface, and there are also can be because of when measure rough surface
There is disconnected light in back scattering reason, so as to cause the interruption of entire measurement process.And absolute type measuring three-dimensional morphology technology is longitudinally surveyed
Amount is not concerned about disconnected light, and refractive index variation is insensitive, but existing absolute type three-dimensional measurement scheme measuring speed is slow, measures non-mould
It is small to paste range, is not all available in many applications.
Summary of the invention
In view of the deficiencies of the prior art, the purpose of the present invention is to provide a kind of three-dimensional shapeds based on the scanning ranging of double light combs
Looks measuring system and method, at least one of to solve the above problems.
The present invention is achieved through the following technical solutions:
As one aspect of the present invention, a kind of three dimensional shape measurement system based on the scanning ranging of double light combs, packet are provided
It includes:Double light combs scan ranging light path module, described for measuring one-dimensional distance information of the measured object on its shoot laser direction
The shoot laser direction of double light comb scanning ranging light path modules is the direction z;Translation module is rotated, it is tested for clamping and moving
Object, while the two-dimensional distance information on the direction measured object x and the direction y being provided;Data acquisition and three-dimensional information processing module, connect
Double light comb scanning ranging light path modules and the rotation translation module are connect, is surveyed for acquiring and integrating double light comb scannings
The two-dimensional distance information that the one-dimensional ranging information and the rotation translation module measured away from light path module provides, obtains measured object
Three-dimensional appearance information.
Preferably, double light comb scanning ranging light path modules include:Main vibration optical frequency com is divided into ginseng through beam splitter
Examine light and measurement light;And local oscillator optical frequency com, two-beam, a branch of and main vibration optical frequency are divided by beam splitter
The reference light of comb is combined and fed to reference signal of the photodetector as ranging, another beam and the main vibration optical frequency com
Measurement light is combined and fed to measuring signal of the photodetector as ranging;Wherein, the main vibration optical frequency com with described
The difference on the frequency of the centre frequency of vibration optical frequency com is f0, the difference on the frequency of repetition rate is Δ frep, f0With Δ frepGuarantee beat frequency letter
Number all positive real numbers of frequency;The ranging optical path of double light comb scanning ranging light path modules is michelson interferometer optical path.
Preferably, the rotation translation module includes:Rotating part, including:Turntable, Plane of rotation is perpendicular to described
The shoot laser of double light comb scanning ranging light path modules;Installing mechanism is located at surveying close to double light comb scannings for the turntable
Side away from light path module, for installing measured object;Translating sections for fixing the rotating part, and make the rotating part
Divide translation, including:Translation stage, translation direction are parallel to the Plane of rotation of the turntable, are the direction x;Wherein, the rotation
Part is worked at the same time with the translating sections, makes the shoot laser of double light comb scanning ranging light path modules on measured object surface
It scans in the shape of a spiral.
Preferably, the rotating part further includes turntable control motor, positioned at the turntable back to described pair
Light comb scans the side of ranging light path module, does uniform angular velocity circular motion for controlling turntable.
Preferably, the translating sections further include translation stage control motor, connect the translation stage, described for controlling
Translation stage does linear uniform motion.
Preferably, the data acquisition and three-dimensional information processing module include part of data acquisition, and sample rate, which is higher than, claps
2 times of frequency signal;And calculation processing part, integrate the one-dimensional ranging that double light comb scanning ranging light path modules measure
The two-dimensional distance information that information and the rotation translation module provide.
Preferably, the calculated relationship of the ranging of double light comb scanning ranging light path modules is:
Wherein, c is the spread speed of light in air, and m is positive integer, faAnd fbIt is the different frequency ingredient of frequency comb, a and b
For positive integer and a > b, a-b=m, fa-fb=m Δ frep,WithIt is J respectivelyaAnd JbOptical path and reference path
Phase difference.
As another aspect of the present invention, a kind of 3 D measuring method based on the scanning ranging of double light combs is provided,
Using the three dimensional shape measurement system above-mentioned based on the scanning ranging of double light combs, include the following steps:Measured object is fixed on rotation
On platform, the surface of measured object and the surface of revolution keeping parallelism of turntable;Translation stage is done under the control of translation stage control motor
Linear uniform motion, turntable do uniform angular velocity circular motion under the control of turntable control motor;Double light combs scan ranging
The measurement laser that light path module is launched is beaten on measured object, and under the movement of rotation translation stage, the measurement laser is tested
Object surface helically moves, and scans entire sample block surface;Data acquisition and three-dimensional information processing module acquisition translation stage control electricity
The control signal reconstruction that machine, turntable control motor goes out the two-dimensional signal in the direction x and y on measured object surface, acquires double light combs and sweeps
It retouches the output signal of two detectors of ranging light path module and calculates the one-dimensional distance information in the direction z.
It can be seen from the above technical proposal that it is of the invention based on double light combs scanning ranging three dimensional shape measurement system and
Method has the advantages that:
(1) poor since small repetition rate can be chosen, the bigger depth of field can be obtained;
(2) since minimum beat frequency rate can be higher, corresponding data updating rate can quickly, and the system of ensure that can reach
Faster measuring speed;
(3) acquisition of one-dimensional distance information, which is surveyed, uses phase method Models of Absolute Distance Measurement Based mode, is not concerned about disconnected light.
Detailed description of the invention
Fig. 1 is the three dimensional shape measurement system figure based on the scanning ranging of double light combs in the embodiment of the present invention;
Fig. 2 is the side view for scanning the three dimensional shape measurement system of ranging in the embodiment of the present invention based on double light combs;
Fig. 3 is that double light combs scan ranging light path module figure in the embodiment of the present invention;
【Figure elements explanation】
1- collimator;2- collimator;
3- collimator;4- measured object;
5- semi-transparent semi-reflecting lens;6- semi-transparent semi-reflecting lens;
7- semi-transparent semi-reflecting lens;8- semi-transparent semi-reflecting lens;
9- photodetector;10- photodetector;
The main vibration optical frequency com of 11-;12- local oscillator optical frequency com;
The bis- light combs of 13- scan ranging light path module;14- measured object;
15- turntable;16- turntable controls motor;
17- rotates translation module by translation stage;18- translation stage controls motor;
The acquisition of 19- data and three-dimensional information processing module;20- fiber coupler.
Specific embodiment
To make the objectives, technical solutions, and advantages of the present invention clearer, below in conjunction with specific embodiment, and reference
Attached drawing, the present invention is described in further detail.
A kind of three dimensional shape measurement system and method based on the scanning ranging of double light combs, the system comprises:Double light combs are swept
Ranging light path module is retouched, for measuring the one-dimensional distance information on the direction measured object z;Translation module is rotated, for clamping and moving
Dynamic measured object, while the two-dimensional distance information on the direction measured object x and the direction y being provided;Data acquisition handles mould with three-dimensional information
Block connects double light comb scanning ranging light path modules and rotation translation module, sweeps for acquiring and integrating double light combs
Retouch the two-dimensional distance information that one-dimensional ranging information that ranging light path module measures and the rotation translation module provide, obtain by
Survey the three-dimensional appearance information of object.The scape of three dimensional shape measurement system based on the scanning ranging of double light combs and method measurement of the invention
Deep big, the speed of measurement is fast, and the acquisition of one-dimensional distance information, which is surveyed, uses Models of Absolute Distance Measurement Based mode, is not concerned about disconnected light, can measure ladder
Face can be used for a variety of commercial measurements.
Specifically, as one aspect of the present invention, a kind of measuring three-dimensional morphology based on the scanning ranging of double light combs is provided
System, including:Double light combs scan ranging light path module, for measuring one-dimensional distance letter of the measured object on its shoot laser direction
The shoot laser direction of breath, double light comb scanning ranging light path modules is the direction z;Translation module is rotated, for clamping and moving
Dynamic measured object, while the two-dimensional distance information on the direction measured object x and the direction y being provided;Data acquisition handles mould with three-dimensional information
Block connects double light comb scanning ranging light path modules and the rotation translation module, for acquiring and integrating double light
The two-dimensional distance information that the one-dimensional ranging information and the rotation translation module that comb scanning ranging light path module measures provide, obtains
To the three-dimensional appearance information of measured object.
Preferably, double light comb scanning ranging light path modules include:Main vibration optical frequency com is divided into ginseng through beam splitter
Examine light and measurement light;And local oscillator optical frequency com, two-beam, a branch of and main vibration optical frequency are divided by beam splitter
The reference light of comb is combined and fed to reference signal of the photodetector as ranging, another beam and the main vibration optical frequency com
Measurement light is combined and fed to measuring signal of the photodetector as ranging;Wherein, the main vibration optical frequency com with described
The difference on the frequency of the centre frequency of vibration optical frequency com is f0, the difference on the frequency of repetition rate is Δ frep, f0With Δ frepGuarantee beat frequency letter
Number all positive real numbers of frequency;The ranging optical path of double light comb scanning ranging light path modules is michelson interferometer optical path.
Preferably, the rotation translation module includes:Rotating part, including:Turntable, Plane of rotation is perpendicular to described
The shoot laser of double light comb scanning ranging light path modules;Installing mechanism is located at surveying close to double light comb scannings for the turntable
Side away from light path module, for installing measured object;Translating sections for fixing the rotating part, and make the rotating part
Divide translation, including:Translation stage, translation direction are parallel to the Plane of rotation of the turntable, are the direction x;Wherein, the rotation
Part is worked at the same time with the translating sections, makes the shoot laser of double light comb scanning ranging light path modules on measured object surface
It scans in the shape of a spiral.
Preferably, the rotating part further includes turntable control motor, positioned at the turntable back to described pair
Light comb scans the side of ranging light path module, does uniform angular velocity circular motion for controlling turntable.
Preferably, the translating sections further include translation stage control motor, connect the translation stage, described for controlling
Translation stage does linear uniform motion.
Preferably, the data acquisition and three-dimensional information processing module include part of data acquisition, and sample rate, which is higher than, claps
2 times of frequency signal;And calculation processing part, integrate the one-dimensional ranging that double light comb scanning ranging light path modules measure
The two-dimensional distance information that information and the rotation translation module provide.
Preferably, the calculated relationship of the ranging of double light comb scanning ranging light path modules is:
Wherein, c is the spread speed of light in air, and m is positive integer, faAnd fbIt is the different frequency ingredient of frequency comb, a and b
For positive integer and a > b, a-b=m, fa-fb=m Δ frep,WithIt is f respectivelyaAnd fbOptical path and reference path
Phase difference.
Preferably, the measurement depth of field of the three dimensional shape measurement system based on the scanning ranging of double light combs is equal to double light combs and sweeps
The non-fuzzy range for retouching ranging, is calculated by the following formula:
Wherein, c is the aerial speed of service of light, frepIt is the repetition rate of main vibration light comb.
As another aspect of the present invention, a kind of 3 D measuring method based on the scanning ranging of double light combs is provided,
Using the three dimensional shape measurement system above-mentioned based on the scanning ranging of double light combs, include the following steps:Measured object is fixed on rotation
On platform, the surface of measured object and the surface of revolution keeping parallelism of turntable;Translation stage is done under the control of translation stage control motor
Linear uniform motion, turntable do uniform angular velocity circular motion under the control of turntable control motor;Double light combs scan ranging
The measurement laser that light path module is launched is beaten on measured object, and under the movement of rotation translation stage, the measurement laser is tested
Object surface helically moves, and scans entire sample block surface;Data acquisition and three-dimensional information processing module acquisition translation stage control electricity
The control signal reconstruction that machine, turntable control motor goes out the two-dimensional signal in the direction x and y on measured object surface, acquires double light combs and sweeps
It retouches the output signal of two detectors of ranging light path module and calculates the one-dimensional distance information in the direction z.
Below in conjunction with specific embodiments and the drawings, the three-dimensional appearance provided by the invention based on the scanning ranging of double light combs is surveyed
Amount system and method is described in further detail.
Embodiment
Fig. 1 is the three dimensional shape measurement system figure based on the scanning ranging of double light combs in the embodiment of the present invention.Fig. 2 is the present invention
The side view of three dimensional shape measurement system based on the scanning ranging of double light combs in embodiment.As shown in Figure 1 and Figure 2, the double light of the present invention
Comb scanning ranging light path module 13, rotation translation module and data acquisition are illustrated with the associated working of three-dimensional information processing module 19
Figure, rotation translation module are made of translation stage 17 and turntable 15 and translation stage control motor 18 and turntable control motor 16.
The translation direction of translation stage 17 is parallel to the Plane of rotation of turntable 15, and Plane of rotation scans ranging perpendicular to double light combs
The shoot laser of light path module.Translation stage 17 does linear uniform motion, turntable 15 under the control of translation stage control motor 18
Uniform angular velocity circular motion is done under the control of turntable control motor 16.Measured object 14 is fixed on turntable 15, is tested
The surface of object 14 and the surface of revolution keeping parallelism of turntable 15.The measurement that double light comb scanning ranging light path modules 13 are launched swashs
Light is beaten on measured object 14, and under the movement of rotation translation stage, measurement light helically moves on measured object surface, is finally scanned whole
A sample block surface.Translation stage controls two of motor 18, turntable control motor 16 and double light combs scanning ranging light path module 13
The output signal of detector is all sent into data acquisition with three-dimensional information processing module 19, which calculates translation stage and control motor
18 and the control signal reconstruction of turntable control motor 16 go out the direction the x and y two-dimensional signal on measured object surface, then collected pair
The output signal of two detectors of light comb scanning ranging light path module 13 and the one-dimensional distance information for calculating the direction z, the direction z
One-dimensional ranging information calculated according to following formula:
Wherein, c is the spread speed of light in air, and m is positive integer, faAnd fbIt is the different frequency ingredient of frequency comb, a and b
For positive integer and a > b, a-b=m, fa-fb=m Δ frep,WithIt is f respectivelyaAnd fbOptical path and reference path
Phase difference.And the depth of field measured is equal to the non-fuzzy range of above-mentioned double optics frequency comb quick distance measurement, and the non-fuzzy of ranging
Range depends on the repetition rate of main vibration light comb, and specific non-fuzzy range can be calculated by the following formula:
Wherein, c is the aerial speed of service of light, frepIt is the repetition rate of main vibration light comb.
Fig. 3 is that double light combs scan ranging light path module figure in the embodiment of the present invention.As described in Figure 3, double light combs of the invention
Ranging light path module is scanned, is had comprising a main vibration optical frequency com 11 and local oscillator optical frequency com 12, two-way optical frequency com
One center frequency difference f0It is Δ f with repetition rate differencerep.The light that main vibration optical frequency com issues is from fiber exit, by collimation
Device 1 becomes spatial light, is divided into two beam spatial lights using semi-transparent semi-reflecting lens 5, gets to all the way as measurement light through semi-transparent semi-reflecting lens 8
On measured object 4, another way is as reference light;The light that local oscillator optical frequency com 12 issues is divided into through 1 × 2 fiber coupler 20
Two-way wherein becoming spatial light by collimator 2 all the way, then passes through a semi-transparent semi-reflecting lens 6 and above-mentioned main vibration optical frequency com
11 reference light converges the reference signal for squeezing into photodetector 9 as ranging;The measurement light of main vibration optical frequency com 11 is from quilt
The light issued through semi-transparent semi-reflecting lens 8 with the collimated mirror 3 of local oscillator optical frequency com 12 after object 4 reflects is surveyed to converge on semi-transparent semi-reflecting lens 7
Unification is the same as the measuring signal squeezed on photodetector 10 as ranging.By the center frequency difference that two-way optical frequency com is arranged
f0With repetition rate difference Δ frep, so that all positive real numbers of frequency of two-way frequency comb beat signal.
In conclusion the depth of field of three dimensional shape measurement system and method measurement based on the scanning ranging of double light combs is bigger,
The speed of measurement is fast, and the acquisition of one-dimensional distance information, which is surveyed, uses Models of Absolute Distance Measurement Based mode, is not concerned about disconnected light, can measure cascaded surface, can
For a variety of commercial measurements.
Particular embodiments described above has carried out further in detail the purpose of the present invention, technical scheme and beneficial effects
Describe in detail bright, it should be understood that the above is only a specific embodiment of the present invention, is not intended to restrict the invention, it is all
Within the spirit and principles in the present invention, any modification, equivalent substitution, improvement and etc. done should be included in protection of the invention
Within the scope of.