CN1420379A - Focussing method of scanning device - Google Patents
Focussing method of scanning device Download PDFInfo
- Publication number
- CN1420379A CN1420379A CN 01137489 CN01137489A CN1420379A CN 1420379 A CN1420379 A CN 1420379A CN 01137489 CN01137489 CN 01137489 CN 01137489 A CN01137489 A CN 01137489A CN 1420379 A CN1420379 A CN 1420379A
- Authority
- CN
- China
- Prior art keywords
- exposure
- sensing element
- sampling
- light sensing
- focal length
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Automatic Focus Adjustment (AREA)
Abstract
A focalizing method for scanner includes respectively moving the optical sensor into several exposure sampling regions, continuous exposing to obtain their characteristic values of focal distances, choosing the optimal focal distance region relative to optimal characteristic value, moving the optical sensor respectively to several exposure sampling points in the optimal region, exposing at each sampling point to obtain the characteristic value of focal distance at each sampling point, and choosing optimal focal distance point relative to the optimal characteristic value to obtain optimal focal distance between optical sensor and lens.
Description
Technical field
The relevant a kind of focusing method of the present invention, and the focusing method of relevant a kind of scanister particularly.
Background technology
In the society now that science and technology is maked rapid progress, scanister (Scanner) has become an indispensable part in modern's life.When user's desire scanned needed contribution pattern, the user can couple scanister and computer usually, and afterwards, the image that the user utilizes scanister scanning contribution pattern and acquisition to be scanned also can store the image that is scanned in the what computer.Wherein the user can with the raising scanning quality, and avoid institute's picked image that the phenomenon that produces distortion is arranged by the image that software processes scanned of computer.So the appearance of scanister brings modern's many conveniences of life really.The structure and the scanning theory thereof of scanister are as follows with accompanying drawings.
Please refer to Fig. 1, it is the side view of general plat form type scanning apparatus.In Fig. 1, scanister 100 comprises main frame 102 and flip 104, and flip 104 is to be connected with main frame 102 by a pivot spigot 106, but and flip 104 dispose on the what main frame 102 in the mode of folding.Main frame 102 comprises scanning glass platform 108, ray machine 110 and light source 112, and scanning glass platform 108 is end faces of what main frame 102, in order to putting file 120 to be scanned, and on the light source 112 configuration what ray machines 110, in order to throw light to file 120 to be scanned and provide scanning required light.In addition, also include catoptron 114, camera lens 116 and light sensing element 118 in the ray machine 110, catoptron 114 can change the working direction of the light that file 120 to be scanned reflected, in order to the light that allows camera lens 116 feed-ins file 120 to be scanned be reflected, and on the focal imaging what light sensing element 118, allow light sensing element 118 get and to capture to the image that is scanned.Wherein, ray machine 110 progressively advances along the direction of the arrow 150 of Fig. 1 by the power that gearing provided in the main frame 102, to continue scanning, makes ray machine 110 to finish according to the image capture of above-mentioned scanning process with whole part of file to be scanned.In addition, the kind of light sensing element 118 is a lot, for example be charge coupled cell (Charge Coupled Device, CCD) and contact image sensor (ContactImage Sensor, CIS).
Generally speaking, also focus in an initial position (HomePosition) before the scanning of ray machine 110 whats in the meeting position what scanister 100, purpose is adjusted the focal length of 118 of camera lens 116 and light sensing elements and is obtained a pinpointed focus at what, make the light of 116 feed-ins of camera lens really on the focal imaging what light sensing element 118, reach the effect of scanning.Wherein, when focusing, stepper motor in the ray machine 110 can be in order to change the relative position of camera lens 116 and light sensing element 118, whereby to adjust focal length, for example be maintained fixed when motionless when camera lens 116, relatively, stepper motor is moving of may command light sensing element 118, is the synoptic diagram of corresponding what focusing stroke when the light sensing element what moves in the conventional practice as shown in Figure 2.Certainly also light sensing element 118 can be designed to immobilize, and allow the moving of stepping Electric Machine Control camera lens 116, even stepper motor moving of may command camera lens 116 and light sensing element 118 all.In Fig. 2, light sensing element 118 is that the direction along the arrow 250 of Fig. 2 moves to final position B by reference position A and near camera lens 116, and light sensing element 118 will form so-called focusing stroke 202 by the path that reference position A moves to final position B, and focusing stroke 202 will be divided into N exposure sampling spot.The stroke 202 of for example focusing is distinguished 100 exposure sampling spot PI-P100.
It should be noted that stepper motor must be controlled on the sampling spot that respectively exposes of light sensing element 118 whats focusings stroke 202 can stop, and a correcting pattern of what scanister 100 is done the sampling point exposure.Scanister 100 will calculate the sampling point focal length eigenvalue of the sampling spot that respectively exposes, and relatively all sampling point focal length eigenvalue Hous can be found out best sampling point focal length eigenvalue.Afterwards, scanister 100 can obtain the pinpointed focus point by the sampling point focal length eigenvalue of the best, and stepper motor will drive light sensing element 118 to pinpointed focus point, make 118 of camera lens 116 and light sensing elements have pinpointed focus, reach the effect of focusing.Yet, also more by what focusing stroke 202 total numbers long and the exposure sampling spot, make that the time of whole focusing is more tediously long, if when the total number of exposure sampling spot is very few, will allow scanister 100 find wrong focal length easily, can't reach the effect of the focusing of expection.In addition, when the light sensing element 118 whats sampling spot that respectively exposes carries out sampling point when exposure, light sensing element 118 can or stop the phenomenon that related generation is trembled a little, the effect of influence focusing because of the driving of stepper motor.
Summary of the invention
Have the mirror what this, the object of the present invention is to provide a kind of focusing method of scanister, focusing method that can be more traditional is quicker to be found pinpointed focus and reduces the time that focusing is spent, and reduce the vibration influence that light sensing element or camera lens are subjected to the driving of stepper motor or driven when stopping, keeping the good result of focusing; Also can avoid producing the very few phenomenon of confusing focal length of exposure number of sampling because of the focusing stroke.
Focusing method in the usefulness what scanister according to an aspect of the present invention, be used to obtain the pinpointed focus between a light sensing element and a camera lens, the described camera lens described light sensing element of what relatively moves to a final position from an initial position, described camera lens is a focusing stroke by the path that described initial position moves between the described final position, described focusing stroke is distinguished into several exposure sampling areas, each described exposure sampling area comprises several exposure sampling spots, be characterized in, said method comprising the steps of: a. moves to described camera lens in each described exposure sampling area, and carry out interval continuous exposure, to obtain the pairing section focal length eigenvalue of each described exposure sampling area; B. selecting the best pairing described exposure sampling area of described section focal length eigenvalue is a pinpointed focus section, described camera lens is moved on each described exposure sampling spot in the described pinpointed focus section, and carry out the sampling point exposure individually, to obtain the pairing sampling point focal length eigenvalue of each described exposure sampling spot; And c. to select the best pairing described exposure sampling spot of described sampling point focal length eigenvalue be pinpointed focus point, and make described camera lens move to and make on the described pinpointed focus point and have described pinpointed focus between described light sensing element and described camera lens.
Focusing method in the usefulness what scanister according to a further aspect of the invention, be used to obtain the pinpointed focus between a light sensing element and a camera lens, the described light sensing element described camera lens of what relatively moves to a final position from an initial position, described light sensing element is a focusing stroke by the path that described initial position moves between the described final position, described focusing stroke is to be distinguished into several exposure sampling areas, each described exposure sampling fauna comprises several exposure sampling spots, be characterized in, described method comprises: a. moves to described light sensing element in each described exposure sampling area, and carry out interval continuous exposure, to obtain the pairing section focal length eigenvalue of each described exposure sampling area; B. selecting the best pairing described exposure sampling area of described section focal length eigenvalue is a pinpointed focus section, described first sensing element is moved on each described exposure sampling spot in the described pinpointed focus section, and carry out the sampling point exposure individually, to obtain the pairing sampling point focal length eigenvalue of each described exposure sampling spot; And c. selects the best pairing described exposure of described sampling point focal length eigenvalue to be sampled as pinpointed focus point, and makes described light sensing element move on the described pinpointed focus point, makes to have described pinpointed focus between described light sensing element and described camera lens.
For above-mentioned purpose of the present invention, characteristics and advantage can be become apparent, a preferred embodiment cited below particularly and conjunction with figs. are described in detail.
Description of drawings
Fig. 1 is the side view of general plat form type scanning apparatus;
Fig. 2 is the synoptic diagram of corresponding what focusing stroke when the light sensing element what moves in the conventional practice;
Fig. 3 is the light sensing element what of a preferred embodiment of the present invention corresponding what focusing stroke synoptic diagram when moving;
Fig. 4 is the process flow diagram of focusing method of the scanister of a preferred embodiment of the present invention;
Fig. 5 is that scanister is according to the synoptic diagram of correcting pattern with calculation of sector focal length eigenvalue.
Embodiment
The special design of the present invention one focusing method, its is with in what one scan device (Scanner), in order to obtaining the pinpointed focus between light sensing element and camera lens, but makes camera lens feed-in light and on the focal imaging what light sensing element.Wherein, this method can be adjusted focal length size between camera lens and light sensing element by stepper motor, for example fixed lens is with mobile light sensing element, or the fixed light sensing element is with moving lens, and the present invention will be that example explains in the mode of fixed lens and mobile light sensing element.In addition, the kind of light sensing element is a lot, for example be charge coupled cell (Charge Coupled Device, CCD) and contact image sensor (Contact Image Sensor, CIS).
Please refer to Fig. 3, it is the light sensing element what of an a preferred embodiment of the present invention corresponding what focusing stroke synoptic diagram when moving.In Fig. 3, light sensing element 318 can move relative to what camera lens 316, and the direction of the arrow from initial position S along Fig. 3 350 moves to final position E, and near what camera lens 316.Wherein, light sensing element 318 forms described focusing stroke 302 by the path that initial position S moves between the final position E, and the present invention is distinguished into several exposure sampling areas with focusing stroke 302, be denoted as expose sampling area TN and writing down in the what scanister of the 1st N of exposure sampling area TI to the from left to right in regular turn, the present invention will be 10 to be the example explanation with the value of N.Each sampling area that exposes comprises several exposure sampling spots, 10 exposure sampling spots for example, and be 100 exposures of the 1st exposure sampling spot KI to the sampling spot K100 from left to right altogether in regular turn.
Please refer to Fig. 4, it is the process flow diagram of focusing method of the scanister of a preferred embodiment of the present invention.In Fig. 4, at first during what step 402, the stroke 302 of will focusing is divided into N exposure sampling area TI-TN, for example the present invention is 10 to be example with the value of N, the stroke 302 of then focusing is divided into 10 exposure sampling areas, is denoted as 10 exposures of the 1st exposure sampling area TI to the sampling area T10 from left to right in regular turn.Wherein, each exposure sampling fauna comprises several exposure sampling spots, and for example the present invention is an example with 10 exposure sampling spots, and then whole focusing stroke 302 has 100 exposure sampling spot KI-K100.Then, enter in the step 404, light sensing element 318 is moved in the sampling area that respectively exposes, and what carries out each interval continuous exposure in one time shutter, and with a correcting pattern is the exposure foundation of light sensing element 318, the section focal length eigenvalue that makes that scanister can respectively be exposed the sample district answered.Wherein, so-called continuous exposure is meant that stepper motor drives light sensing element 318 in the mode of continuous running, the mode what that makes light sensing element 318 to move continuously respectively exposes and exposes in the sampling area, and what reaches required exposure in fixing time shutter.In addition, the present invention is definition one parameter n, by the drive of the stepper motor in the scanister, makes n exposure of light sensing element 318 whats sampling area carry out interval continuous exposure, and obtains corresponding section focal length eigenvalue.
Right Hou enters step 406, judges whether the value of n waits what N, if it is correct, then enter step 410, otherwise, step 408 will be entered, the n value is added 1 and get back to step 404, form a loop, make n+1 exposure of first sensing element 318 whats sampling area carry out another interval continuous exposure, and obtain another section focal length eigenvalue, the rest may be inferred and obtain N section focal length eigenvalue, just 10 section focal length eigenvalues.
Then, in step 410, scanister will be by the section focal length eigenvalue of selecting a best in N the section focal length eigenvalue, and with the pairing exposure sampling area of section focal length eigenvalue of the best as a pinpointed focus section, and the present invention will be referred to as focal length coarse adjustment method with the process that obtains the pinpointed focus section.So scanister is drive stepping motor, make stepper motor drive on the sampling spot that respectively exposes of light sensing element 318 to the pinpointed focus section, to carry out the sampling point exposure individually.Wherein, the exposure of so-called sampling point is meant that stepper motor drives light sensing element 318 in the mode of step-operated, makes mode that light sensing element 318 can stepping arrive on the sampling spot that respectively exposes and exposes.And with a correcting pattern is the exposure foundation of light sensing element 318, makes can obtain 10 sampling point focal length eigenvalues altogether by the scanister pairing sampling point focal length of the sampling spot eigenvalue that can respectively be exposed.
How calculating section focal length eigenvalue about scanister will be summarized as follows, please refer to Fig. 5, and it is that scanister is according to the synoptic diagram of correcting pattern with calculation of sector focal length eigenvalue.In Fig. 5, correcting pattern 502 has several alternate black and white strips, and can respectively be exposed by the waveform to the signal of video signal of the correcting pattern 502 scanning Hou gained interval focal length characteristic of sampling area of scanister.Wherein, Y-axis is represented the amplitude size of the detected light signal of light sensing element, and amplitude is bigger, the focal length eigenvalue is also bigger, and the present invention will select the focal length eigenvalue of the highest focal length eigenvalue for the best, and X-axis is represented the alternate distributing position of black and white strip of the relative what correcting pattern 502 of waveform.In addition, the amplitude of waveform 504 is big than the amplitude of waveform 506, the interval focal length eigenvalue performance of promptly representing waveform 504 is bigger than the interval focal length eigenwert of waveform 506, and then scanister will select the interval focal length eigenwert of waveform 504 to be best interval focal length eigenwert.
Then, in step 412, scanister will be by the focal length eigenwert of selecting a best in 10 sampling point focal length eigenwerts, and be pinpointed focus point with the pairing exposure sampling spot of sampling point focal length eigenwert of the best, so, scanister makes stepper motor drive light sensing element 318 to pinpointed focus point drive stepping motor, allows 316 on light sensing element 318 and camera lens have pinpointed focus.Therefore the present invention obtains focal length, so in this constipation bundle focusing method of the present invention, and the present invention will be referred to as the focal length method for trimming by the process that obtains pinpointed focus in the pinpointed focus.It should be noted that the sampling point focal length eigenwert of the best of how choosing as for scanister, its mode also as shown in Figure 5, promptly scanister will be chosen the pairing sampling point focal length of the waveform with peak swing eigenwert and be best sampling point focal length eigenwert.
Focusing method of the present invention is successively to divide into focal length coarse adjustment method and focal length fine tuning method, and the present invention is divided into several exposure sampling areas with the focusing stroke, and the sampling area that respectively exposes is divided into several exposure sampling spots again.At first, in focal length coarse adjustment method, the present invention allows light sensing element carry out interval continuous exposure in each exposure sampling area, to find the pinpointed focus section.Afterwards, in focal length fine tuning method, the present invention makes the sampling spot that respectively exposes in the light sensing element what pinpointed focus section carry out the sampling point exposure again, to find pinpointed focus and pinpointed focus.So the focusing method that the present invention is more traditional is quicker to be found pinpointed focus and reduce time of focusing, and reduce the vibration influence that light sensing element is subjected to the driving of stepper motor or driven when stopping, and the number of sampling of more can avoiding exposing is very few and confuse focal length.Yet person skilled in the art person can understand technology of the present invention must not limit what this, for example the present invention can be with light sensing element fixing and moving lens to change focal length, also can reach the effect of above-mentioned focusing method.
The focusing method of the scanister that the above-mentioned preferred embodiment of the present invention is disclosed has following advantage:
1. the quicker pinpointed focus that finds of focusing method that can be more traditional, and reduce the time that focusing is spent.
2. reduce the vibration influence that light sensing element or camera lens are subjected to losing of stepper motor or driven when stopping, keeping the good result of focusing.
3. avoid producing the very few phenomenon of confusing focal length of exposure number of sampling because of the focusing stroke.
In sum; though the present invention is disclosed by a preferred embodiment; yet this preferred embodiment is not to be used to limit the present invention; any person skilled in the art person without departing from the spirit and scope of the present invention; when can making various changes and replacement, so protection scope of the present invention should be as the criterion with the attached scope that claims were defined of Hou.
Claims (10)
1. one kind with the focusing method in the what scanister, be used to obtain the pinpointed focus between a light sensing element and a camera lens, the described camera lens described light sensing element of what relatively moves to a final position from an initial position, described camera lens is a focusing stroke by the path that described initial position moves between the described final position, described focusing stroke is distinguished into several exposure sampling areas, each described exposure sampling area comprises several exposure sampling spots, it is characterized in that, said method comprising the steps of:
A. described camera lens is moved in each described exposure sampling area, and carry out interval continuous exposure, to obtain the pairing section focal length eigenvalue of each described exposure sampling area;
B. selecting the best pairing described exposure sampling area of described section focal length eigenvalue is a pinpointed focus section, described camera lens is moved on each described exposure sampling spot in the described pinpointed focus section, and carry out the sampling point exposure individually, to obtain the pairing sampling point focal length eigenvalue of each described exposure sampling spot; And
C. selecting the best pairing described exposure sampling spot of described sampling point focal length eigenvalue is pinpointed focus point, and makes described camera lens move to and make on the described pinpointed focus point and have described pinpointed focus between described light sensing element and described camera lens.
2. focusing method as claimed in claim 1 is characterized in that, described focusing stroke is distinguished into N exposure sampling area, is respectively N exposure of one the 1st exposure sampling area to a sampling area, and described step a comprises:
A1. set a parameter n, the n value is 1;
A2. described camera lens is moved in described n the exposure sampling area, and carry out interval continuous exposure, to obtain described n the pairing n of an exposure sampling area section focal length eigenvalue; And
Whether the value of a3. judging described parameter n waits what N, if, then enter described step b, otherwise, the n value is added 1, and repeating step a2.
3. focusing method as claimed in claim 1 is characterized in that, among the described step a of what, the action of interval continuous exposure is that what was finished in one time shutter.
4. focusing method as claimed in claim 1 is characterized in that, described light sensing element is a charge coupled cell.
5. focusing method as claimed in claim 1 is characterized in that, described light sensing element is a contact image sensor.
6. one kind with the focusing method in the what scanister, be used to obtain the pinpointed focus between a light sensing element and a camera lens, the described light sensing element described camera lens of what relatively moves to a final position from an initial position, described light sensing element is a focusing stroke by the path that described initial position moves between the described final position, described focusing stroke is to be distinguished into several exposure sampling areas, each described exposure sampling fauna comprises several exposure sampling spots, it is characterized in that described method comprises:
A. described light sensing element is moved in each described exposure sampling area, and carry out interval continuous exposure, to obtain the pairing section focal length eigenvalue of each described exposure sampling area;
B. selecting the best pairing described exposure sampling area of described section focal length eigenvalue is a pinpointed focus section, described first sensing element is moved on each described exposure sampling spot in the described pinpointed focus section, and carry out the sampling point exposure individually, to obtain the pairing sampling point focal length eigenvalue of each described exposure sampling spot; And
C. select the best pairing described exposure of described sampling point focal length eigenvalue to be sampled as pinpointed focus point, and make described light sensing element move on the described pinpointed focus point, make to have described pinpointed focus between described light sensing element and described camera lens.
7. focusing method as claimed in claim 6 is characterized in that, described focusing stroke is distinguished into N exposure sampling area, is respectively N exposure of one the 1st exposure sampling area to a sampling area, and described step a comprises:
A1. set a parameter n, the n value is 1;
A2. described light sensing element is moved in described n the exposure sampling area, and carry out interval continuous exposure, to obtain described n the pairing n of an exposure sampling area section focal length eigenvalue; And
Whether the value of a3. judging described parameter n waits what N, if, then enter described step b, otherwise, the n value is added 1, and repeating step a2.
8. focusing method as claimed in claim 6 is characterized in that, among the described step a of what, the action of interval continuous exposure is that what was finished in one time shutter.
9. focusing method as claimed in claim 6 is characterized in that, described light sensing element is a charge coupled cell.
10. focusing method as claimed in claim 6 is characterized in that, described light sensing element is a contact image sensor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 01137489 CN1420379A (en) | 2001-11-16 | 2001-11-16 | Focussing method of scanning device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 01137489 CN1420379A (en) | 2001-11-16 | 2001-11-16 | Focussing method of scanning device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1420379A true CN1420379A (en) | 2003-05-28 |
Family
ID=4674212
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 01137489 Pending CN1420379A (en) | 2001-11-16 | 2001-11-16 | Focussing method of scanning device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1420379A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107748428A (en) * | 2017-10-18 | 2018-03-02 | 歌尔股份有限公司 | Screen detects Atomatic focusing method and device |
| WO2022052066A1 (en) * | 2020-09-11 | 2022-03-17 | 西门子（中国）有限公司 | Method and apparatus for realizing focusing of industrial camera |
-
2001
- 2001-11-16 CN CN 01137489 patent/CN1420379A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107748428A (en) * | 2017-10-18 | 2018-03-02 | 歌尔股份有限公司 | Screen detects Atomatic focusing method and device |
| WO2022052066A1 (en) * | 2020-09-11 | 2022-03-17 | 西门子（中国）有限公司 | Method and apparatus for realizing focusing of industrial camera |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100704083B1 (en) | Method and apparatus for determining optical distance | |
| US5362958A (en) | Reading apparatus with position calculation and focus adjustment and curved surface adjustment | |
| EP1458181B1 (en) | Digital camera with distance-dependent focussing method | |
| US5235375A (en) | Focusing position detecting and automatic focusing apparatus with optimal focusing position calculation method | |
| JPH09149207A (en) | Image reader | |
| CN1229931A (en) | Automatic focusing method | |
| WO1999021352A1 (en) | Image reading device and focus adjustment method for it | |
| JP4089426B2 (en) | Projector, imaging device, keystone correction program | |
| EP1713262B1 (en) | Method for focussing a film scanner and film scanner for carrying out the method | |
| CN1420379A (en) | Focussing method of scanning device | |
| CN2321022Y (en) | Automatic focusing device | |
| JP3448829B2 (en) | Image reading device | |
| JP3601272B2 (en) | Imaging device | |
| US5946028A (en) | Apparatus and method for controlling magnification of image in camera | |
| JP3362927B2 (en) | Image reading device | |
| CN1164962C (en) | Multiple-resolution scanner with automatic focusing function and its focusing method | |
| US5410420A (en) | Drum scanner focusing system | |
| JPH08336065A (en) | Original illuminator and image input device | |
| US20040175205A1 (en) | Original reading apparatus | |
| JP3648946B2 (en) | Image reading apparatus and focus adjustment method thereof | |
| JPH0785125B2 (en) | Focus adjustment device | |
| JPH06113081A (en) | Picture reader | |
| JPH11127313A (en) | Image reader and its focusing method | |
| JP2621265B2 (en) | Surface analysis mapping device | |
| JPH08159919A (en) | Center positioning method for chart |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| AD01 | Patent right deemed abandoned | ||
| C20 | Patent right or utility model deemed to be abandoned or is abandoned |