CN101428521A - Energy compensation process for laser inside-carving - Google Patents
Energy compensation process for laser inside-carving Download PDFInfo
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- CN101428521A CN101428521A CNA200810217075XA CN200810217075A CN101428521A CN 101428521 A CN101428521 A CN 101428521A CN A200810217075X A CNA200810217075X A CN A200810217075XA CN 200810217075 A CN200810217075 A CN 200810217075A CN 101428521 A CN101428521 A CN 101428521A
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Abstract
The invention relates to an energy compensation method used for laser engraving. The method comprises the steps of supplying a laser with a Q switch, calculating out the needed energy value of the scan central point and the needed energy value of the point farthermost from the central point when conducting laser engraving; establishing the function of displacement and needed energy between the displacement from the central point and the needed energy value; establishing function between the displacement from the scan central point and the establishment time according to the establishment time of the reproduced pulse of the laser and the needed energy, and conducting energy compensation to scan points in different positions through the Q adjustment by the Q switch according to the function between the displacement from the scan central point and the establishment time, changing the Q adjustment pulse width frequency and the pulse width through adjusting Q by the Q switch and increasing energy compensation, so as to conveniently and effectively carry out compensation to the energy loss of different scan points, thereby ensuring that the burst and lighting degree of the entire scan range reaches a uniform level and relative uniform engraving effect can be achieved in the entire scan range.
Description
Technical field
The present invention relates to a kind of energy compensation process, relate in particular to a kind of energy compensation process that is used for body laser inner carving.
Background technology
The body laser inner carving technology is in the transparent body (as crystal, glass, acrylic etc.) internal focus with the pulse light laser, produce the gasification micro-crack of micron dimension size, by the locus of computer control micro-crack in the transparent body, make the micro-crack three-dimensional arrangement and constitute stereo-picture, micro-crack is the nonlinear interaction of the fundamental frequency of nanosecond laser or the frequency multiplication and the transparent body and produce the destruction of catastrophe.
Laser sub-marker is at first by dedicated points cloud switching software, convert two dimension or 3-D view/portrait to the point cloud chart picture, then according to the arrangement of putting, by the position of laser controlling software control crystal and the output of laser, when crystal is in a certain ad-hoc location, the laser that control program control in the controller in the laser sub-marker focuses on will be got light shot point one by one in quartzy inside, image/portrait of carving in a large amount of light shot points has just formed and wanted.
Laser sub-marker wherein a kind of employing be the station machine, it is that crystal is bonded on the workbench, rotate by the driven by motor leading screw of X and Y2 direction workbench is moved, the Z axle move then Electric Machine Control by Z-direction.Because this machinery moves and need be with load, so speed can not be too fast, causes the carving speed of station machine generally all not reach theoretical maximum, far can not satisfy the needs of interior carving at a high speed.
Another kind is exactly the galvanometer laser sub-marker, and galvanometer control engraving with the mode that is similar to optical scanning, so speed is very fast by the control direction of light, almost can work near under the situation of theoretical maximal rate.
The galvanometer laser sub-marker generally comprises laser instrument, beam expanding lens, galvanometer, F-Theta mirror.Galvanometer inside is provided with motor and drives galvanometer deflection.
The galvanometer laser sub-marker sends high energy laser beam by laser instrument, behind beam expanding lens expansion bundle, is transferred on the galvanometer by light-guiding system, by through the F-Theta mirror, forms a scanning area under computer control.The galvanometer laser sub-marker adopts galvanometer deflection way control laser focus point, deflection control laser beam by galvanometer moves arbitrarily on the machined surface of the transparent body, the control transparent body that moves up and down of the workbench by the carrying transparent body moves up and down the position and reaches laser beam and focus on the inner different depth position of the transparent body, reaches the purpose of carrying out the stereo carving image.
The galvanometer laser sub-marker is to utilize galvanometer deflection to make laser beam incident from different perspectives finish whole scanning process, incoming laser beam is its incident angle difference when the scanning zones of different, incoming laser beam is through the area difference of transparent body surface contact hot spot, reach the not influence of equal factor of the degree of depth that incoming laser beam penetrates in the transparent body, cause the energy loss degree varies to cause, and show that through practice identical single pulse energy is at scanning area decentre diverse location, it is also different the inner generation of transparent body blow-up point shape, and form more the place engraving more light effect far away more from the scanning area center, cause pattern to seem dim, unintelligible.
Summary of the invention
The technical problem to be solved in the present invention provides a kind of method that can effectively carry out energy compensating when carrying out body laser inner carving.
The present invention is achieved through the following technical solutions:
A kind of energy compensation process that is used for body laser inner carving of the present invention,
May further comprise the steps:
Laser instrument is provided, and described laser instrument is provided with Q-switch;
The required energy value of sweep center point when estimating body laser inner carving reaches from the required energy value in scanning center solstics;
Foundation between the displacement of sweep center point and required energy value displacement and the functional relation of institute's energy requirement;
Required energy is converted into the required output energy of output pulse of laser instrument during with body laser inner carving;
According to the Time Created of laser instrument output pulse and the relation of required output energy, set up from the displacement of sweep center point and the functional relation of Time Created;
According to from the displacement of sweep center point and the functional relation of Time Created, Q-switch transfers Q that control Time Created is carried out energy compensating to the scanning element of diverse location.
Further, the functional relation of being set up between described displacement and the institute's energy requirement is the curvilinear function relation.
Further, described body laser inner carving time institute energy requirement compensates by the single pulse energy of regulating laser instrument output.
Further, described body laser inner carving time institute energy requirement compensates adjusting by the pulse power of regulating laser instrument output.
Further, the described body laser inner carving time institute energy requirement pulse frequency and the pulsewidth of regulating laser instrument output by Q-switch compensates.
Further, described energy compensating does not compensate in the focus point hot spot region of incoming laser beam scanning center.
A kind of energy compensation process that is used for body laser inner carving may further comprise the steps:
Laser instrument is provided, and described laser instrument is provided with Q-switch;
The energy value that sweep center point when estimating body laser inner carving is required and apart from the required energy value in scanning center solstics;
With the sweep center point is zero point, with sweep center point and zero energy is initial point, foundation is the two-dimensional coordinate system of parameter with displacement and institute's energy requirement of sweep center point, in coordinate system, indicate sweep center point and the required pairing coordinate points of energy value, and from the displacement coordinate in scanning center solstics and the required pairing coordinate points of energy, 2 are connected with smooth curve, set up and the displacement of sweep center point and the functional relation of institute's energy requirement according to the smooth curve function that is connected;
Required energy is converted into the required output energy of output pulse of laser instrument during with body laser inner carving;
According to the Time Created of the output pulse of laser instrument and the relation of required output energy, set up from the displacement of sweep center point and the functional relation of Time Created;
According to from the displacement of sweep center point and the functional relation of Time Created, Q-switch transfers Q that the scanning element of diverse location is carried out energy compensating.
Further, described body laser inner carving time institute energy requirement compensates by the single pulse energy of regulating laser instrument output.
Further, described body laser inner carving time institute energy requirement compensates adjusting by the pulse power of regulating laser instrument output.
Further, the described body laser inner carving time institute energy requirement pulse duration frequency and the pulsewidth of regulating the pulse of laser instrument output by Q-switch compensates.
A kind of energy compensation process that is used for body laser inner carving of the present invention is by setting up the displacement between the displacement of sweep center point and required energy value and the functional relation of institute's energy requirement; According to the Time Created of laser instrument output pulse and the relation of required output energy, set up from the displacement of sweep center point and the functional relation of Time Created; According to functional relation from Time Created of the displacement of sweep center point and institute's energy requirement, thereby transfer Q to carry out energy compensating to regulating the scanning element of controlling diverse location Time Created by control program control Q-switch, transfer Q to change by Q-switch and transfer Q pulse duration frequency and pulsewidth, increase single pulse energy, energy loss to different scanning point compensates easily and effectively, so that reach uniformity, carve out consistent relatively engraving effect in whole sweep limits in the brightness of whole sweep limits blow-up point.
The specific embodiment
A kind of energy compensation process that is used for body laser inner carving of the present invention.The galvanometer laser sub-marker is to utilize galvanometer deflection to make laser beam incident from different perspectives finish whole scanning process, incoming laser beam through the area difference of transparent body surface contact hot spot, and the not influence of equal factor of the degree of depth that penetrates in the transparent body of incoming laser beam, causes the energy loss degree varies to cause in scanning its incident angle difference during zones of different, incoming laser beam.When practical operation according to practice show identical single pulse energy whole in the energy loss rule of carving process the variation of the incident angle of incoming laser beam play a major role.The variation of incident angle can cause the focal beam spot shape of incoming laser beam, the variation of size and the variable in distance that incoming laser beam penetrates the transparent body etc.The variation of incident angle is presented as different scanning areas on the transparent body to be processed.With the incoming laser beam vertical incidence transparent body is that sweep starting point is the scanning center zone, plays its scanning area and change apart from the distance in scanning center zone and change apart from the displacement of sweep center point when incident angle changes.Practice shows the point far away more apart from scanning center, and the loss of its energy is also big more, but since the invariable incident angle of its incoming laser beam of focus point hot spot region of scanning center in the focus point hot spot region of incoming laser beam scanning center, do not compensate.
Because the galvanometer laser sub-marker adopts semiconductor laser, the high speed performance of the motor that drives galvanometer deflection is not fully exerted.Laser instrument adopts semiconductor laser to describe in the present embodiment.
A kind of energy compensation process that is used for body laser inner carving of the present invention, the laser instrument that provides is provided with Q-switch, and promptly laser instrument adopts the Q-switch laser instrument, and the Q-switch laser instrument is provided with Q-switch, Q-switch can improve laser output power and compress width by changing the Q value of laser cavity.The Q value of laser cavity (quality factor that also claims the chamber) is to describe the amount of laser instrument laser cavity loss size.The laser cavity that optical loss is low, its Q value is high.
Q value defined: the energy of the energy of storage in the Q=2 π chamber/per second loss
Make laser cavity be in the low reactance-resistance ratio state during beginning, promptly improve oscillation threshold, vibration can not be generated, the inverted population of last energy level just can accumulate in a large number, when running up to maximum (saturation value), the loss in chamber is reduced, the Q value is uprushed, correspondingly, the laser generation threshold value also reduces suddenly, and laser generation is set up rapidly, the inverted population of energy level is consumed in the extremely short time, change the light energy in the chamber into, the output in the chamber discharges energy with single impulse form, so just obtain the very high pulse laser output of peak power.
It is Time Created that the counter-rotating particle reaches the required time Bup of critical value (being oscillation threshold) from the low pulse value of original state.
The accumulated number of inverted population was directly proportional with the time in the laser cavity, many more its of quantity accumulation of its inverted population is that the interior light energy of laser cavity is many more, be laser instrument average light power with Time Created Bup be directly proportional, promptly Time Created, Bup was long more, the power of the pulse of output is high more.
It is by carrying out the integration time of control laser cavity self-energy to the pulse duration frequency of pulse and the adjusting of pulsewidth that thereby Q-switch is transferred Q.Thereby by transferring Q that laser output power is improved by certain program rule, laser pulse width compresses by certain program rule.
Q-switch transfer Q be exactly make the chamber by certain method the Q value in time by certain change of program, thereby to regulating control by certain procedure the integration time (being the integration time of inverted population) of laser cavity self-energy.
A kind of energy compensation process that is used for body laser inner carving of the present invention is that body laser inner carving time institute energy requirement is compensated by the single pulse energy of regulating laser instrument output, further single pulse energy is changed into pulse power and compensates adjusting.Pulse frequency and pulsewidth that the present invention transfers Q to regulate laser instrument output by Q-switch are to increase single pulse energy, so that reach uniformity in the brightness of whole sweep limits blow-up point.Because the invariable incident angle of its incoming laser beam of focus point hot spot region of scanning center, the energy loss of itself and sweep center point is much the same, so do not compensate in the focus point hot spot region of incoming laser beam scanning center.
A kind of energy compensation process that is used for body laser inner carving of the present invention, the required energy value of the sweep center point when at first estimating body laser inner carving reaches from the required energy value of the point of scanning center's maximum displacement;
Set up from the displacement between the displacement of sweep center point and the required energy value and the curvilinear function of institute's energy requirement according to the required energy value of sweep center point and from the required energy value of the point of scanning center's maximum displacement and to concern; This curvilinear function can for just, cosine, logarithmic function and parabolic function, hyperbolic function etc.
Required energy is converted into the required laser instrument output output energy of pulse during with body laser inner carving;
According to the Time Created of laser instrument output pulse and the relation of required output energy, set up from the displacement of sweep center point and the functional relation of Time Created;
Will be apart from the displacement of sweep center point and the functional relation of Time Created, be input in the control program of controller of laser sub-marker, transfer Q that the scanning element of diverse location is carried out energy compensating by control program control Q-switch.
A kind of energy compensation process that is used for body laser inner carving of the present invention also can be realized in the following way
The energy value that sweep center point when estimating body laser inner carving is required and apart from the required energy value of the point of scanning center's maximum displacement;
With the sweep center point is zero point, with sweep center point and zero energy is initial point, foundation is the two-dimensional coordinate system of parameter apart from the displacement of sweep center point and institute's energy requirement of corresponding displacement, indicate the required energy value of sweep center point and respective point corresponding coordinate points and from the point of scanning center's maximum displacement and respective point institute energy requirement corresponding coordinate points in coordinate system in coordinate system, connect 2 points with smooth curve, set up functional relation with the some institute energy requirement of the displacement of sweep center point and corresponding displacement according to the function of smooth curve;
Required energy is converted into the required output energy of output pulse of laser instrument during with body laser inner carving;
According to the Time Created of the output pulse of laser instrument and the relation of required output energy, set up from the displacement of sweep center point and the functional relation of Time Created;
Will be apart from the displacement of sweep center point and the functional relation of Time Created, be input in the control program of controller of laser sub-marker, transfer Q that the scanning element of diverse location is carried out energy compensating by control program control Q-switch.
Adopt in the present embodiment cosine function as in the control program as the functional relation of energy compensating, a kind of energy compensation process that is used for body laser inner carving of the present invention:
The required energy value of sweep center point when at first estimating body laser inner carving reaches from the required energy value of the point of scanning center's maximum displacement; In the present embodiment in the point of scanning center's maximum displacement is the effective scanning scope of galvanometer from the point of scanning center's maximum displacement.
Set up displacement and institute's energy requirement cosine function relational expression between the displacement of sweep center point and required energy value according to the required energy value of sweep center point and from the required energy value of the point of scanning center's maximum displacement;
Required energy is converted into the required laser instrument output output energy of pulse during with body laser inner carving;
According to the Time Created of laser instrument output pulse and the relation of required output energy, set up apart from the displacement of sweep center point and the cosine function relational expression of Time Created;
Will be apart from the displacement of sweep center point and the cosine function relational expression of Time Created, be input in the control program of controller of laser sub-marker, transfer Q that the scanning element of diverse location is carried out energy compensating by control program control Q-switch.
As can followingly expressing of energy compensating that one embodiment of the present of invention are set up apart from the displacement of sweep center point and the cosine function relational expression of Time Created:
Be T1 the Time Created of the energy that sweep center point (or scanning center zone) is required;
Be T2 the Time Created apart from the required energy of the point of scanning center's maximum displacement;
Be similar to and think that the radius in scanning center zone is the border circular areas of r;
Displacement (being radius) apart from the point of scanning center's maximum displacement apart from sweep center point is R;
The energy compensating rule of setting up by be expressed as apart from the displacement of sweep center point and the cosine function relational expression of Time Created: T=T1+{1+COS[(1-r/R Time Created of incoming laser beam place processing stand institute energy requirement during body laser inner carving) * π] * (T2-T1)/2
The specific embodiment of the above is a better embodiment of the present invention, is not to limit concrete practical range of the present invention with this, and the equivalence that all shapes according to the present invention, structure, method are done changes all in protection scope of the present invention.
Claims (10)
1. an energy compensation process that is used for body laser inner carving is characterized in that, may further comprise the steps:
Laser instrument is provided, and described laser instrument is provided with Q-switch;
The required energy value of sweep center point when estimating body laser inner carving reaches from the required energy value of the point of scanning center's maximum displacement;
Foundation between the displacement of sweep center point and required energy value displacement and the functional relation of institute's energy requirement;
Required energy is converted into the required laser instrument output output energy of pulse during with body laser inner carving;
According to the Time Created of laser instrument output pulse and the relation of required output energy, set up from the displacement of sweep center point and the functional relation of Time Created;
According to from the displacement of sweep center point and the functional relation of Time Created, Q-switch transfers Q that the scanning element of diverse location is carried out energy compensating.
2. a kind of energy compensation process that is used for body laser inner carving according to claim 1 is characterized in that: the functional relation of being set up between described displacement and the institute's energy requirement is the curvilinear function relation.
3. a kind of energy compensation process that is used for body laser inner carving according to claim 1 is characterized in that: described body laser inner carving time institute energy requirement compensates by the single pulse energy of regulating laser instrument output.
4. a kind of energy compensation process that is used for body laser inner carving according to claim 1 is characterized in that: described body laser inner carving time institute energy requirement compensates adjusting by the pulse power of regulating laser instrument output.
5. a kind of energy compensation process that is used for body laser inner carving according to claim 1 is characterized in that: pulse frequency and pulsewidth that described body laser inner carving time institute energy requirement is regulated laser instrument output by Q-switch compensate.
6. a kind of energy compensation process that is used for body laser inner carving according to claim 1 is characterized in that: described energy compensating does not compensate in the focus point hot spot region of incoming laser beam scanning center.
7. an energy compensation process that is used for body laser inner carving is characterized in that, may further comprise the steps:
Laser instrument is provided, and described laser instrument is provided with Q-switch;
The energy value that sweep center point when estimating body laser inner carving is required and apart from the required energy value of the point of scanning center's maximum displacement;
With the sweep center point is zero point, with sweep center point and zero energy is initial point, foundation is the two-dimensional coordinate system of parameter apart from the displacement of sweep center point and institute's energy requirement of corresponding displacement, indicate the required energy value of sweep center point and respective point corresponding coordinate points and from the point of scanning center's maximum displacement and respective point institute energy requirement corresponding coordinate points in coordinate system in coordinate system, connect 2 points with smooth curve, set up functional relation with the some institute energy requirement of the displacement of sweep center point and corresponding displacement according to the function of smooth curve;
Required energy is converted into the required output energy of output pulse of laser instrument during with body laser inner carving;
According to the Time Created of the output pulse of laser instrument and the relation of required output energy, set up from the displacement of sweep center point and the functional relation of Time Created;
According to from the displacement of sweep center point and the functional relation of Time Created, Q-switch transfers Q that the scanning element of diverse location is carried out energy compensating.
8. a kind of energy compensation process that is used for body laser inner carving according to claim 7 is characterized in that: described body laser inner carving time institute energy requirement compensates by the single pulse energy of regulating laser instrument output.
9. a kind of energy compensation process that is used for body laser inner carving according to claim 7 is characterized in that: described body laser inner carving time institute energy requirement compensates adjusting by the pulse power of regulating laser instrument output.
10. a kind of energy compensation process that is used for body laser inner carving according to claim 7 is characterized in that: pulse duration frequency and pulsewidth that described body laser inner carving time institute energy requirement is regulated the pulse of laser instrument output by Q-switch compensate.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810217075XA CN101428521B (en) | 2008-10-24 | 2008-10-24 | Energy compensation process for laser inside-carving |
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| Application Number | Priority Date | Filing Date | Title |
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| CN200810217075XA CN101428521B (en) | 2008-10-24 | 2008-10-24 | Energy compensation process for laser inside-carving |
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| CN101428521A true CN101428521A (en) | 2009-05-13 |
| CN101428521B CN101428521B (en) | 2010-08-11 |
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| CN200810217075XA Expired - Fee Related CN101428521B (en) | 2008-10-24 | 2008-10-24 | Energy compensation process for laser inside-carving |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108015414A (en) * | 2017-11-23 | 2018-05-11 | 北京环境特性研究所 | A kind of laser three-dimensional inside engraving machining energy dynamic compensating system and its operating method |
| CN108415878A (en) * | 2018-01-26 | 2018-08-17 | 广州新可激光设备有限公司 | A kind of speed at laser equipment mark edge enhances optimization method |
| CN108581242A (en) * | 2018-01-26 | 2018-09-28 | 广州新可激光设备有限公司 | A kind of energy at laser equipment mark edge enhances optimization method |
-
2008
- 2008-10-24 CN CN200810217075XA patent/CN101428521B/en not_active Expired - Fee Related
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108015414A (en) * | 2017-11-23 | 2018-05-11 | 北京环境特性研究所 | A kind of laser three-dimensional inside engraving machining energy dynamic compensating system and its operating method |
| CN108015414B (en) * | 2017-11-23 | 2020-07-14 | 北京环境特性研究所 | Laser three-dimensional inner engraving processing energy dynamic compensation system and operation method thereof |
| CN108415878A (en) * | 2018-01-26 | 2018-08-17 | 广州新可激光设备有限公司 | A kind of speed at laser equipment mark edge enhances optimization method |
| CN108581242A (en) * | 2018-01-26 | 2018-09-28 | 广州新可激光设备有限公司 | A kind of energy at laser equipment mark edge enhances optimization method |
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| CN101428521B (en) | 2010-08-11 |
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