CN102122055A - Laser-type automatic focusing device and focusing method thereof - Google Patents
Laser-type automatic focusing device and focusing method thereof Download PDFInfo
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- CN102122055A CN102122055A CN201110067679.2A CN201110067679A CN102122055A CN 102122055 A CN102122055 A CN 102122055A CN 201110067679 A CN201110067679 A CN 201110067679A CN 102122055 A CN102122055 A CN 102122055A
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Abstract
The invention provides a laser-type automatic focusing device comprising a laser transmitter, a raster lens, a focusing mirror, a reflector, an objective lens, an image acquisition device and an image processing device. Laser which is emitted by the laser transmitter is filtered with the raster lens, rest laser passes through the focusing mirror to form parallel light, and the parallel light is reflected through the reflector, focused on a measured object through the objective lens capable of automatically adjusting the position, reflected back in a path symmetric with the reflecting and focusing path and finally transmitted to the image acquisition device by the raster lens to process acquired information. The automatic focusing device provided by the invention shortens the focusing time and improves the focusing accuracy. The focusing method provided by the invention can rapidly judge a defocusing state, controls a motor unidirectionally and lessens the work of processing a great deal of image information so as to greatly shorten focusing time without weakening focusing accuracy and greatly improve focusing performance.
Description
Technical field
The invention belongs to the optical detective technology field, relate in particular to a kind of laser type automatic focusing mechanism and focusing method thereof.
Background technology
Along with the fast development of automatic control technology and image processing techniques, adopt the Autofocus Technology of image processing method to be applied to a plurality of fields, such as industrial optical detection, medical image system, multimedia technology field etc.Usually need exact instrument is carried out quality testing in commercial production, this victory of will seeking quickness, accurately obtain distinct image information, Autofocus Technology highlights crucial effects.General, adopting the microscope focusing mode automatically of image processing method is to present whole inverted image after reflexing to convex lens by natural light, by the camera continuously shot images, and constantly compare and analyze, control moving lens repeatedly, up to finding out the most distinct image as the criterion of focus point, yet, great amount of images information need be stored and handle to this automatic focusing mode, and influence is the speed of focusing automatically, and the degree of accuracy of focusing is not high yet.
Summary of the invention
At the existing deficiency of above-mentioned existing focusing technology, the invention provides a kind of laser type automatic focusing mechanism, this focusing mechanism has reduced the focusing time, has improved the precision of focusing simultaneously.
Another object of the present invention provides a kind of focusing method of laser type automatic focusing mechanism, this focusing method can be judged out-of-focus appearance fast, folk prescription is to the control motor, reduced the work of handling great amount of images information, thereby greatly reduced the focusing time, do not reduce simultaneously the precision of focusing again, greatly improved the focusing performance.
Technical solution of the present invention is: a kind of laser type automatic focusing mechanism, comprise generating laser, the grating eyeglass, focus lamp, catoptron, object lens, image collecting device and image processing apparatus, the laser that described generating laser is launched filters through the grating eyeglass, the remaining light velocity forms behind the parallel rays reflection by catoptron through focus lamp, again through adjusting the object lens focusing of position automatically to testee, afterwards, this light reflects back with the path with described path symmetry, reflex in the image collecting device by the grating eyeglass then, send to image processing apparatus at last Information Monitoring is handled.
Described grating eyeglass be arranged to can elimination half laser beam.
The relative position of the parts except that described object lens is for fixing.
Described object lens drive focusing by motion-control module and focusing driving module, and wherein, motion-control module is used to change the horizontal coordinate position of focusing, thereby focusing driving module is used to change the image-forming information that object distance changes testee.
Described focusing driving module is a driven by servomotor.
Described driven by servomotor step-length is 1 μ m.
Described image collector is changed to the ccd image acquisition module.
To further being improved to of this scheme: also comprise the video module that is used to observe the focusing platform environment.
Further be improved to again: also comprise the memory module that is used for picture information and result of calculation.
A kind of focusing method of laser type automatic focusing mechanism may further comprise the steps:
1) image collecting device images acquired information;
2) image information that collects is transported to image processing apparatus and carries out gradation conversion;
3) the gained gray-scale value is averaged gray-scale value and calculate, present upper semi-circle, center circle, three kinds of light spot images of lower half circle;
4) analyze the gray-scale value and the gray-scale value cut-point of above-mentioned three kinds of light spot images by the gray analysis method, judge that out-of-focus appearance is that last out of focus is still descended out-of-focus appearance;
5) control the motor folk prescription to the mobile object lens of operation according to the gained out-of-focus appearance;
6) two field picture gray-scale value before and after the contrast;
7) according to gradient method, judge the turning point of gray value gradient direction, find out the minimum average B configuration gray-scale value, determine the focal plane.
Automatic focusing mechanism provided by the present invention has reduced the focusing time, has improved the precision of focusing simultaneously.Focusing method provided by the present invention can be judged out-of-focus appearance fast, and folk prescription has reduced and handled the work of great amount of images information, thereby greatly reduced the focusing time to the control motor, does not reduce the precision of focusing simultaneously again, has greatly improved the focusing performance.
Description of drawings
Fig. 1 is the laser optics loop synoptic diagram of the embodiment of the invention;
Fig. 2 is the hot spot out-of-focus appearance analysis chart of the embodiment of the invention;
Fig. 3 is embodiment of the invention focusing method flow diagram;
Fig. 4 is the initial out-of-focus appearance gray analysis figure of the embodiment of the invention;
Fig. 5 is the initial accurate focusing state gray analysis figure of the embodiment of the invention.
Embodiment
The present invention is described further below in conjunction with the drawings and specific embodiments.
As shown in Figure 1, a kind of laser type automatic focusing mechanism, comprise generating laser 1, grating eyeglass 2, focus lamp 3, catoptron 4, object lens 5, image collecting device 7 and image processing apparatus, the laser that described generating laser 1 is launched filters through grating eyeglass 2, pass through the reflection of catoptron 4 behind the remaining light velocity process focus lamp 3 formation parallel rayss, focus on the testee 6 through the object lens 5 that can adjust the position automatically again, afterwards, this light reflects back with the path with described path symmetry, reflex in the image collecting device 7 by grating eyeglass 2 then, send to image processing apparatus at last Information Monitoring is handled.
Described grating eyeglass 2 be arranged to can elimination half laser beam.
The relative position of the parts except that described object lens 5 is for fixing.
Described object lens 5 drive focusing by motion-control module and focusing driving module, and wherein, motion-control module is used to change the horizontal coordinate position of focusing, thereby focusing driving module is used to change the image-forming information that object distance changes testee.
Described focusing driving module is a driven by servomotor.
Described driven by servomotor step-length is 1 μ m.
Described image collecting device 7 is the ccd image acquisition module.
To further being improved to of this scheme: also comprise the video module that is used to observe the focusing platform environment.
Further be improved to again: also comprise the memory module that is used for picture information and result of calculation.
A kind of focusing method of laser type automatic focusing mechanism may further comprise the steps:
1) image collecting device images acquired information;
2) image information that collects is transported to image processing apparatus and carries out gradation conversion;
3) the gained gray-scale value is averaged gray-scale value and calculate, present upper semi-circle, center circle, three kinds of light spot images of lower half circle;
4) analyze the gray-scale value and the gray-scale value cut-point of above-mentioned three kinds of light spot images by the gray analysis method, judge that out-of-focus appearance is that last out of focus is still descended out-of-focus appearance;
5) control the motor folk prescription to the mobile object lens of operation according to the gained out-of-focus appearance,, then control motor and move down object lens if be in out-of-focus appearance down, otherwise, then control and move object lens on the motor;
6) two field picture gray-scale value before and after the contrast;
7) according to gradient method, judge the turning point of gray value gradient direction, find out the minimum average B configuration gray-scale value, determine the focal plane.
The image-forming principle of laser type automatic focusing mechanism of the present invention meets the convex lens image-forming principle.With reference to Fig. 1, according to the convex lens image-forming principle, the testee 6 that height is H is at object lens 5 and catoptron 4 through having focal distance f, forming height on focus lamp 3 is the inverted image of h, and wherein, object lens 5 are object distance to the distance A of testee 6, focus lamp 3 is image distance to grating eyeglass 2 apart from a, so, according to the principle of convex lens imaging, focal distance f and object distance A and image distance a should satisfy the following relationship formula:
Yet, because the special optical loop of half light, so that have only object image-forming half, for the collection of image,, satisfy following relational expression according to light geometric relationship shown in Figure 1:
With reference to Fig. 1, the horizontal sextant angle θ of grating eyeglass 2 is 45 °, and its true imaging that finally projects in the ccd image acquisition module is of a size of rh, satisfies following relational expression:
rh?=?
（3）
In conjunction with formula (2) and formula (3), can obtain:
A=a
（4）
Formula (4) is brought into formula (1), can obtains:
More than calculate the focal length under the correct focusing situation.
Object lens 5 are removable in the automatic focusing mechanism of the present invention, remaining component is for fixing, therefore, image distance a immobilizes, in conjunction with above calculating, want as can be known to realize that correct focusing needs to adjust object distance A, the present invention's method of focusing moves up and down object lens 5 by the control motor, its object distance A is equated with focal distance f, thereby realize accurately focusing.
With reference to Fig. 1, by mobile object lens, out of focus, accurate focusing and three kinds of states of following out of focus can appear going up, correspondingly, project three kinds of light spot images of the same appearance of image information of ccd image acquisition module, with reference to Fig. 2, under the perfect condition, last out-of-focus appearance presents upper semi-circle light spot image P1, and accurately focusing presents centre dot spot pattern P2, and following out-of-focus appearance presents lower half circle light spot image P3.
With reference to Fig. 3, the present invention of this flow chart description finishes a kind of method of focusing, carries out with following steps: the S1:CCD image capture module is gathered light spot image information, obtains image information; S2: carry out gradation conversion according to the gradation conversion formula, draw the gray-scale value of pixel i:
S3: image segmentation; S4: extract first gradation of image value, calculate average gray value; S5: extract second gradation of image value, calculate average gray value; S6: compare gray-scale value, judge out-of-focus appearance, gathering the picture pixel is 640 * 480, and in conjunction with formula (6), obtains the average gray computing formula of half range picture:
（7）
Relatively go up half range light spot image and following half range light spot image average gray value, judge original state; S7:, then control and move object lens on the motor if be in out-of-focus appearance; S8: then control motor and move down object lens if original state is the non-out-of-focus appearance that goes up; So only need unidirectional motion, avoid object lens to pump; S9: the object lens moving step length is 1 μ m, the gray-scale value of nearest 10 two field pictures of real-time storage in the object lens moving process; S10: comparison performs an analysis, draw the gray value gradient direction, gray value gradient direction up to certain frame picture N changes, it is the gradient turning point, the focal plane that then can tentatively draw N frame correspondence is best focusing, for guaranteeing accuracy, continue to analyze N+10 two field picture gray value gradient direction, finally reach accurate judgement focal plane; S11: mobile motor, and finish focusing.
According to gray analysis, following two kinds of situations can appear in the present invention's method of focusing:
The first, initial out-of-focus appearance.With reference to Fig. 4, original state is in out-of-focus appearance, average gray value is non-minimum value, and along with object lens move, gray-scale value presents and reduces the phenomenon that afterwards increases earlier, and the gradient direction of gray-scale value changes at the N place, becomes negative sense from forward, continue to analyze N+10 two field picture gray value gradient direction, can determine that step-length is that corresponding focal plane, N place is accurate focussing plane;
The second, initial accurate focusing state.With reference to Fig. 5, original state is in accurate focusing state just, and gray-scale value is minimum, and moves gray-scale value with object lens and increase gradually, and the gray value gradient direction do not change, and can determine that original state is accurate focusing state.
Automatic focusing mechanism provided by the present invention has reduced the focusing time, has improved the precision of focusing simultaneously.Focusing method provided by the present invention can be judged out-of-focus appearance fast, and folk prescription has reduced and handled the work of great amount of images information, thereby greatly reduced the focusing time to the control motor, does not reduce the precision of focusing simultaneously again, has greatly improved the focusing performance.
Claims (10)
1. laser type automatic focusing mechanism, comprise generating laser (1), grating eyeglass (2), focus lamp (3), catoptron (4), object lens (5), image collecting device (7) and image processing apparatus, it is characterized in that: the laser that described generating laser (1) is launched filters through grating eyeglass (2), pass through the reflection of catoptron (4) behind remaining light velocity process focus lamp (3) the formation parallel rays, focus on the testee (6) through the object lens (5) that can adjust the position automatically again, afterwards, this light reflects back with the path with described path symmetry, reflex in the image collecting device (7) by grating eyeglass (2) then, send to image processing apparatus at last Information Monitoring is handled.
2. laser type automatic focusing mechanism according to claim 1 is characterized in that: described grating eyeglass (2) be arranged to can elimination half laser beam.
3. laser type automatic focusing mechanism according to claim 2 is characterized in that: the relative position of the parts except that described object lens (5) is for fixing.
4. laser type automatic focusing mechanism according to claim 3, it is characterized in that: described object lens (5) drive focusing by motion-control module and focusing driving module, wherein, motion-control module is used to change the horizontal coordinate position of focusing, thereby focusing driving module is used to change the image-forming information that object distance changes testee.
5. laser type automatic focusing mechanism according to claim 4 is characterized in that: described focusing driving module is a driven by servomotor.
6. laser type automatic focusing mechanism according to claim 5 is characterized in that: described driven by servomotor step-length is 1 μ m.
7. laser type automatic focusing mechanism according to claim 1 is characterized in that: described image collecting device (7) is the ccd image acquisition module.
8. laser type automatic focusing mechanism according to claim 1 is characterized in that: also comprise the video module that is used to observe the focusing platform environment.
9. laser type automatic focusing mechanism according to claim 1 is characterized in that: also comprise the memory module that is used for picture information and result of calculation.
10. the focusing method of a laser type automatic focusing mechanism may further comprise the steps:
1) image collecting device images acquired information;
2) image information that collects is transported to image processing apparatus and carries out gradation conversion;
3) the gained gray-scale value is averaged gray-scale value and calculate, present upper semi-circle, center circle, three kinds of light spot images of lower half circle;
4) analyze the gray-scale value and the gray-scale value cut-point of above-mentioned three kinds of light spot images by the gray analysis method, judge that out-of-focus appearance is that last out of focus is still descended out-of-focus appearance;
5) control the motor folk prescription to the mobile object lens of operation according to the gained out-of-focus appearance;
6) two field picture gray-scale value before and after the contrast;
7) according to gradient method, judge the turning point of gray value gradient direction, find out the minimum average B configuration gray-scale value, determine the focal plane.
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Cited By (9)
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|---|---|---|---|---|
| CN103674839A (en) * | 2013-11-12 | 2014-03-26 | 清华大学 | Visual sample positioning operating system and method based on light spot detection |
| CN105763775A (en) * | 2016-03-02 | 2016-07-13 | 太仓思比科微电子技术有限公司 | Automatic focusing digital camera for body surface detection |
| CN106094194A (en) * | 2016-08-17 | 2016-11-09 | 江浩 | The acquisition methods of samples pictures, imaging device and the method for acquisition samples pictures thereof under microscope |
| CN106769993A (en) * | 2016-12-21 | 2017-05-31 | 北京农业信息技术研究中心 | Sample compressing tablet bogey, terahertz light spectral measurement system and measuring method |
| CN107390356A (en) * | 2017-08-28 | 2017-11-24 | 电子科技大学 | The method focused on automatically based on representation of laser facula |
| CN108288836A (en) * | 2018-03-23 | 2018-07-17 | 罗毅霖 | It is a kind of that the long-range barrier clearing device of molten electric transmission line hot-line and method are cut based on laser |
| CN112399070A (en) * | 2019-08-19 | 2021-02-23 | 生昊 | Method, device, equipment and storage medium for assisting camera in fast focusing |
| CN113070566A (en) * | 2021-03-02 | 2021-07-06 | 苏州科韵激光科技有限公司 | Automatic focus searching method and device |
| CN115229330A (en) * | 2022-09-22 | 2022-10-25 | 武汉引领光学技术有限公司 | Automatic focusing device and method for laser processing |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101770065A (en) * | 2010-01-12 | 2010-07-07 | 广东工业大学 | Superfine automatic focusing system based on multi-platform and realization method thereof |
-
2011
- 2011-03-21 CN CN201110067679.2A patent/CN102122055A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101770065A (en) * | 2010-01-12 | 2010-07-07 | 广东工业大学 | Superfine automatic focusing system based on multi-platform and realization method thereof |
Non-Patent Citations (2)
| Title |
|---|
| 《中国激光》 20110228 范富明等 "TFT-LCD检测中基于激光三角法的显微镜离焦快速在线检测及补偿" 全文 1-10 第38卷, 第2期 2 * |
| 《光电工程》 20100531 范富明等 "一种新型光学快速自动聚焦系统" 第127-130页 1-10 第37卷, 第5期 2 * |
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| CN103674839B (en) * | 2013-11-12 | 2016-01-06 | 清华大学 | A kind of visual Sample location operating system based on spot detection and method |
| CN103674839A (en) * | 2013-11-12 | 2014-03-26 | 清华大学 | Visual sample positioning operating system and method based on light spot detection |
| CN105763775A (en) * | 2016-03-02 | 2016-07-13 | 太仓思比科微电子技术有限公司 | Automatic focusing digital camera for body surface detection |
| CN106094194A (en) * | 2016-08-17 | 2016-11-09 | 江浩 | The acquisition methods of samples pictures, imaging device and the method for acquisition samples pictures thereof under microscope |
| CN106094194B (en) * | 2016-08-17 | 2019-06-14 | 江浩 | The acquisition methods, imaging device of samples pictures and its method for obtaining samples pictures under microscope |
| CN106769993B (en) * | 2016-12-21 | 2023-05-26 | 北京农业信息技术研究中心 | Sample tabletting bearing device, terahertz spectrum measuring system and measuring method |
| CN106769993A (en) * | 2016-12-21 | 2017-05-31 | 北京农业信息技术研究中心 | Sample compressing tablet bogey, terahertz light spectral measurement system and measuring method |
| CN107390356A (en) * | 2017-08-28 | 2017-11-24 | 电子科技大学 | The method focused on automatically based on representation of laser facula |
| CN108288836A (en) * | 2018-03-23 | 2018-07-17 | 罗毅霖 | It is a kind of that the long-range barrier clearing device of molten electric transmission line hot-line and method are cut based on laser |
| CN112399070B (en) * | 2019-08-19 | 2022-04-19 | 生昊 | Method, device, equipment and storage medium for assisting camera in fast focusing |
| CN112399070A (en) * | 2019-08-19 | 2021-02-23 | 生昊 | Method, device, equipment and storage medium for assisting camera in fast focusing |
| CN113070566A (en) * | 2021-03-02 | 2021-07-06 | 苏州科韵激光科技有限公司 | Automatic focus searching method and device |
| CN113070566B (en) * | 2021-03-02 | 2022-05-27 | 苏州科韵激光科技有限公司 | Automatic focus searching method and device |
| CN115229330A (en) * | 2022-09-22 | 2022-10-25 | 武汉引领光学技术有限公司 | Automatic focusing device and method for laser processing |
| CN115229330B (en) * | 2022-09-22 | 2022-12-13 | 武汉引领光学技术有限公司 | Automatic focusing device and method for laser processing |
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Application publication date: 20110713 |