CN103826030B

CN103826030B - There is the image read-out of lens error correction function

Info

Publication number: CN103826030B
Application number: CN201310743904.9A
Authority: CN
Inventors: 井原好顺; 长谷川孝美; 渡边毅; 浅野长武
Original assignee: JAI Co Ltd
Current assignee: JAI Co Ltd
Priority date: 2012-11-16
Filing date: 2013-11-16
Publication date: 2016-07-06
Anticipated expiration: 2033-11-16
Also published as: CN103826030A; JP2014103461A

Abstract

The present invention relates to a kind of just can be revised by the digital filter in an only direction when switching and switch over caused by optical element chromatic aberration, gamut produced by distortion aberration the image read-out with lens error correction function.Described lens error correction unit possesses: digital filter bank, by one of multiple coloured light being controlled using the time delay that the aberration by described optical element causes of each reading image of line image sensor as benchmark coloured light, using all the other as other coloured light, it is disposed in this remaining coloured light respectively；Delay control unit, based on the filter coefficient of the measurement value described digital filter bank of control of each retardation between the image of benchmark coloured light and other coloured light；And memorizer, when the picture transverse width of other coloured light described is relative to the picture transverse width width of described benchmark coloured light, read under the state of picture position of the end of scan end of benchmark coloured light and other coloured light at the same time, start reading out from the scanning starting end image of other coloured light described, based on the measurement value scanning each retardation that starting end image is benchmark with benchmark coloured light, control the filter coefficient of described digital filter bank, the gamut produced by the aberration of described optical element can be revised.

Description

There is the image read-out of lens error correction function

Technical field

The present invention relates to revise and carried out the image read-out with lens error correction function of the aberration that the optical element of imaging causes by the image that reads of original copy etc..

Background technology

As to original copy etc. read image carry out imaging optical element lens in there is aberration, the refractive index being because glass as the chromatic aberration of one is slightly different according to wavelength produced by (dispersion).

This is revealed as on axle chromatic aberration and multiplying power chromatic aberration, as colour with and when using three line image sensor (lineimagesensor), it is necessary to respective with RGB be disposed in imaging point position Wavelength matchedly.

Although it addition, the above-mentioned aberration aberration that to be all the size of the stain with image, image space and image relevant, but, in addition, also have as the aberration that the distortion overall with the shape of picture is relevant and distort aberration.

Generally, the figure having tetragon is the tubbiness distortion aberration of barrel distortion and the distortion aberration of the pillow in pillow distortion.This distortion aberration has following characteristic, i.e. although at the immediate vicinity of image almost without distortion, but, along with close to its distortion variations of periphery and also become larger.Even if in line imageing sensor, its main scanning direction is also affected by the same impact distorting aberration.

In recent years, the development of the high-resolutionization of image read-out, therefore, the valid pixel number of line image sensor seeking to use is many, and seeks the downsizing for the densification of miniaturization, Pixel Dimensions and pel spacing.

Therefore, gamut produced by the chromatic aberration allowed in the past, distortion aberration becomes problem, it is desirable to use the image read-out of the amending unit selecting and embedded in aberration of lens.

nullTherefore，In patent documentation 1 Japanese Unexamined Patent Publication 06-086082 publication，Following invention disclosed in its claim 1: " a kind of image read-out，Scan manuscript face，Converged by imaging len and this master copy is carried out the light that transmission or reflection is obtained，Incide the components of photo-electric conversion，Detect the signal of telecommunication corresponding with the reflectance of described master copy or absorbance as picture signal，The picture signal of this detection is imported to red respectively、Blue、The signal processing part of green each signal component，Thus，Obtain color image information，Described image read-out is characterised by，At red signal composition、The rear class of the described signal processing part of blue signal component is connected to reading position deviation correction circuit，Described reading position deviation correction circuit has the digital filter unit of Parameters variation on main scanning direction，And their parameter setting is mutual substantially contrary weight about locus.”.

Specifically, as the explanation of Fig. 2, in paragraph [0021], for " ....First, in the first half of the main scanning of the computing of R component, carry out as follows, i.e. for making the G-signal of one pixel of delay, at first with the R signal of big weight mixing non-delayed, at first with the R signal of little one pixel of weight Mixed Delay.On the other hand, operate in the way of to make weight reversion along with the central part close to main scanning.”.

It addition, " R component computing main scanning later half in ..., for guaranteeing the seriality of G-signal, still make one amount of pixels of delay, make R signal this amount of also bulk delay with an amount of pixels delay circuit 20.And, at first half and the later half switching on-off circuit 32 of main scanning, the reading gamut correction output of R signal imports to lead-out terminal 35 via FIFO memory 33.”.

The reading position deviation correction of B component carries out in accordance with the modification method of R component, all with G component for benchmark, carries out the calculation process of R component, B component.

Prior art literature

Patent documentation

Patent documentation 1: Japanese Unexamined Patent Publication 06-086082 publication.

Summary of the invention

The problem that invention to solve

In patent documentation 1, G component as the benchmark of this calculation process also carries out delay disposal with digital filter, and then, in the B component of the later half R component of the computing of main scanning or first half, R signal, B signal bulk delay together is made with an amount of pixels delay circuit 20, therefore, digital filter is passed twice through.

Therefore, there is the following problem that should solve, namely, need to make the G component as benchmark by a kind of digital filter, make R/B composition respectively through two kinds of digital filters, additionally, need the coefficients R OM for producing weight big at first, for producing the coefficients R OM of the weight of most lower primary school and for the mlultiplying circuit mixed, add circuit, it addition, first half and the switching of later half needs in main scanning switch, circuit complicated etc..

Therefore, a kind of image read-out with lens error correction function is provided, even if being subject to the chromatic aberration that optical element has, the impact distorting aberration, when the picture transverse width of the image of other coloured light broadens relative to the picture transverse width of the image of benchmark coloured light or the time of narrowing, and then from the scanning starting end of image to image middle position and from image middle position to end of scan end, chromatic aberration, distortion aberration the gamut produced is modified by the digital filter that also can pass through an only direction when switching and switch over.

For solving the scheme of problem

The present inventor solves above-mentioned problem by following means.

(1) a kind of image read-out with lens error correction function, has: multiple line image sensors, and subject picture light is carried out light-to-current inversion respectively；And lens error correction unit, to will read the multiplying power chromatic aberration of the image optical element that is imaged on each line image sensor and distort at least any of aberration of aberration and be modified, described in there is the image read-out of lens error correction function be characterised by,

Described lens error correction unit possesses:

Digital filter bank, it is made up of multiple digital filters, input the digitized picture signal of carrying out reading image of described line image sensor, by one of multiple coloured light being controlled using the time delay that the aberration by described optical element causes of each reading image of described line image sensor as benchmark coloured light, using remaining coloured light as other coloured light, it is disposed in this other coloured light respectively；

Delay control unit, based on the measurement value of each retardation between the image of described benchmark coloured light and the image of other coloured light described, controls the filter coefficient of described digital filter bank；And

Memorizer, stores the measurement value of described retardation and described reading image,

In described delay control unit,

At least any of aberration of aberration is distorted at the multiplying power chromatic aberration and tubbiness that are subject to described optical element, thus when the picture transverse width of the image of other coloured light described broadens relative to the picture transverse width of the image of described benchmark coloured light,

Read under the state of picture position of the end of scan end image of described benchmark coloured light and the end of scan end image of other coloured light described at the same time,

Start reading out from the scanning starting end image of other coloured light described, measurement value based on each retardation of other coloured light that the scanning starting end image of described benchmark coloured light is stored in as benchmark described memorizer, control the filter coefficient of described digital filter bank, thus, revise the gamut produced by the aberration of described optical element

In described delay control unit,

At least any of aberration of aberration is distorted at the multiplying power chromatic aberration and pillow that are subject to described optical element, thus when the picture transverse width of the image of other coloured light described narrows relative to the picture transverse width of the image of described benchmark coloured light,

Read under the state of picture position of the scanning starting end image of described benchmark coloured light and the scanning starting end image of other coloured light described at the same time,

Start reading out from the scanning starting end image of described benchmark coloured light He other coloured light, measurement value based on each retardation of other coloured light that the scanning starting end image of described benchmark coloured light is stored in as benchmark described memorizer, control the filter coefficient of described digital filter bank, thus, the gamut produced by the aberration of described optical element is revised.

(2) a kind of image read-out with lens error correction function, has: multiple line image sensors, and subject picture light is carried out light-to-current inversion respectively；And lens error correction unit, to will read the multiplying power chromatic aberration of the image optical element that is imaged on each line image sensor and distort at least any of aberration of aberration and be modified, described in there is the image read-out of lens error correction function be characterised by,

Described lens error correction unit has:

Digital filter bank, it is made up of multiple digital filters, input the digitized picture signal of carrying out reading image of described line image sensor, be disposed in each of white light of the multiple coloured light being controlled time delay caused with the aberration by described optical element of each reading image of described line image sensor；

Delay control unit, using one of the plurality of coloured light as benchmark coloured light, using remaining coloured light as other coloured light, based on the pixel readout clock of described line image sensor and described benchmark coloured light or the measurement value as the retardation between the image of the white light of other coloured light, control the filter coefficient of described digital filter bank；And

As one man carry out imaging at each image of the plurality of coloured light and the valid pixel width of described line image sensor, and be subject to the multiplying power chromatic aberration of described optical element and when tubbiness distorts at least any of aberration of aberration,

In described delay control unit,

Under the state of the pixel readout clock of the described line image sensor of the end of scan end image of the end of scan end image reading each image of the plurality of coloured light at the same time and each image reading the plurality of coloured light,

The measurement value of the readout clock of the scanning starting end image of each image read from the plurality of coloured light to the line image sensor of end of scan end image and the retardation of each image of the plurality of coloured light is written to described memorizer,

Each image at the plurality of coloured light carries out imaging with being unsatisfactory for the valid pixel width of described line image sensor, and is subject to the multiplying power chromatic aberration of described optical element and when pillow distorts at least any of aberration of aberration,

In described delay control unit,

Under the state of the pixel readout clock of the scanning starting end image of each image of the scanning starting end image reading each image of the plurality of coloured light at the same time and the plurality of coloured light reading described line image sensor,

The measurement value of the readout clock of the scanning starting end image of each image read from the plurality of coloured light to the described line image sensor of end of scan end image and the retardation of each image of the plurality of coloured light is written to described memorizer,

Based on the measurement value of the described retardation read from described memorizer, control to press the filter coefficient of the digital filter bank of each arranging of the plurality of coloured light, thus, revise the gamut produced by the aberration of described optical element.

(3) image read-out with lens error correction function according to preceding paragraph (1) or (2), it is characterized in that, described lens error correction unit is by sequential reading out the filter coefficient that the measurement value of the described retardation being stored in described memorizer controls the digital filter bank of each arranging by the plurality of coloured light, it is thus possible to output have modified the picture signal of aberration continuously.

(4) image read-out with lens error correction function according to any one of preceding paragraph (1)～(3), it is characterized in that, described lens error correction unit the integer of whole pixel counts of described line image sensor is divided one pixel count as a collection (set), to collect unit control filter coefficient, revise the gamut produced by the aberration distortion caused by described optical element.

(5) image read-out with lens error correction function according to any one of preceding paragraph (1)～(4), it is characterized in that, control the pixel count of the collection unit of described integer divides as follows, namely, the region distorting aberration little near imaging picture central authorities makes pixel count increase, along with making pixel count reduce close to scanning starting end or end of scan end near picture central authorities.

(6) image read-out with lens error correction function according to any one of preceding paragraph (1)～(5), it is characterised in that described reference colours just green light, other coloured light described is red light and blue light.

Following effect can be played by the present invention.

(1) present invention is a kind of image read-out with lens error correction function, has: multiple line image sensors, and subject picture light is carried out light-to-current inversion respectively；And lens error correction unit, it is modified by least any of aberration of the multiplying power chromatic aberration and distortion aberration that read the optical element that image is imaged on each line image sensor,

Described lens error correction unit possesses:

In described delay control unit,

By being set to read the state of the picture position of the end of scan end image of the end of scan end image of described benchmark coloured light and other coloured light described simultaneously, thus the picture signal of other coloured light described all becomes leading phase relative to the picture signal of described benchmark coloured light

Therefore, can start reading out from the scanning starting end image of other coloured light described, measurement value based on each retardation of other coloured light that the scanning starting end image of benchmark coloured light is stored in as benchmark described memorizer, control the filter coefficient of described digital filter bank, thus, revise by the chromatic aberration of described optical element, distort the gamut that aberration produces.

Or, in described delay control unit,

By being set to read the state of the picture position of the scanning starting end image of the scanning starting end image of described benchmark coloured light and other coloured light described simultaneously, thus the picture signal of other coloured light described all becomes leading phase relative to the picture signal of described benchmark coloured light

Therefore, can start reading out from the scanning starting end image of described benchmark coloured light He other coloured light, measurement value based on each retardation of other coloured light that the scanning starting end image of benchmark coloured light is stored in as benchmark described memorizer, control the filter coefficient of described digital filter bank, thus, revise by the chromatic aberration of described optical element, distort the gamut that aberration produces.

Additionally, even if by the image utilizing described optical element to obtain have tubbiness distort when characteristic or pillow distort characteristic distort gamut that aberration causes by relative to benchmark coloured light in the first half of the main scanning of other coloured light and the later half of main scanning contrary in the way of different, also can revise the chromatic aberration caused by described optical element of whole scanning area successively by the digital filter bank in the only direction arranged by other coloured light each, distort the gamut that aberration produces, accordingly, it is capable to seek simplification and the cost reduction of device.

(2) present invention is a kind of image read-out with lens error correction function, has: multiple line image sensors, and subject picture light is carried out light-to-current inversion respectively；And lens error correction unit, to will read the multiplying power chromatic aberration of the image optical element that is imaged on each line image sensor and distort at least any of aberration of aberration and be modified, described in there is the image read-out of lens error correction function be characterised by,

Described lens error correction unit has:

In described delay control unit,

By being set to read the state of the pixel readout clock of the described line image sensor of the end of scan end image of each image of the end of scan end image of each image of the plurality of coloured light and the plurality of coloured light of reading simultaneously, thus each image signal of the plurality of coloured light reads relative to described pixel all becomes leading phase all the time

In described delay control unit,

By being set to read the state of the pixel readout clock of the scanning starting end image of each image of the plurality of coloured light of the scanning starting end image of each image of the plurality of coloured light and the described line image sensor of reading simultaneously, thus each image signal of the plurality of coloured light reads relative to described pixel all becomes leading phase all the time

Measurement value based on the described retardation read from described memorizer, control to press the filter coefficient of the digital filter bank of each arranging of the plurality of coloured light, thus, can not have the readout clock of lead-lag, for the benchmark digital filter bank in an only direction, simultaneously and each picture signal is revised gamut exactly that is produced by the aberration of described optical element and by the chromatic aberration of described optical element, the gamut distorting described benchmark coloured light that aberration produces and other coloured light in electricity, moreover it is possible to seek simplification and the cost reduction of measuring device etc..

Additionally, as other method, described lens error correction unit by the image of other coloured light described or with described benchmark coloured light for benchmark have modified other coloured light described in the gamut produced by the aberration of described optical element picture signal and have modified with described readout clock for benchmark the gamut produced by the aberration of described optical element benchmark coloured light picture signal between the measurement value of each retardation be written to described memorizer

Measurement value based on the described retardation read from described memorizer, control the filter coefficient of other coloured light digital filter bank described, thus, the gamut produced by the aberration of described optical element can be revised, therefore, by after revising the gamut of image of pixel readout clock and benchmark coloured light, revise the gamut between the picture signal of other coloured light described that is between the described picture signal of benchmark coloured light and the image of other coloured light or that have modified gamut, it is thus possible to in electricity without the readout clock of lead-lag for benchmark, obtain correction multiplying power chromatic aberration completely, distort aberration, picture signal entirely without gamut.

(3) in the present invention, in addition to the above-described effects, described lens error correction unit sequential reads out the measurement value of the described retardation being stored in described memorizer, control is by the filter coefficient of the digital filter bank being made up of multiple digital filters of each arranging of the plurality of coloured light, it is thus possible to output have modified the picture signal of aberration continuously, therefore, measurement value according to the retardation sequential read out, by controlling the filter coefficient of digital filter bank, the gamut during whole scannings of described line image sensor can be revised, therefore, even if by when measuring so that the measurement object on the production line conveyer belt of constant speed drive carries out subscan, also the image output that have modified aberration can be continuously available.

null(4) in the present invention，In addition to the above-described effects，Described lens error correction unit the integer of whole pixel counts of described line image sensor is divided one pixel count as a collection，To collect unit control filter coefficient，Revise the gamut that the aberration distortion caused by described optical element produces，Therefore，Even the line image sensor that pixel count is many，By the integer of whole pixel counts is divided one pixel count revise, as a collection, the gamut caused by the aberration distortion of described optical element，It is thus possible to by each the collection unit between be stored between the image of benchmark coloured light of described memorizer and the image of other coloured light or pixel readout clock and reference colours photoimaging image，Measurement value based on retardation，Control the filter coefficient of described digital filter bank successively，Revise the gamut of whole image，Therefore，The high speed of image procossing can be sought，Simultaneously also economical.

(5) in the present invention, in addition to the above-described effects, if controlling the pixel count of the collection unit of described integer divides as follows, namely, the region distorting aberration little near imaging picture central authorities makes pixel count increase, along with making pixel count reduce close to scanning starting end or end of scan end near picture central authorities, then can seek the high speed of image procossing further.

(6) in the present invention, in addition to the above-described effects, described reference colours just green light, other coloured light described is red light and blue light, spectral sensitivity characteristic according to line image sensor, the sensory characteristic of green light is good, can with the level higher than other two coloured light and high S/N than obtaining corresponding excellent picture signal, it is therefore preferable that described green light is as reference light.

Accompanying drawing explanation

Fig. 1 is the circuit block diagram of the image read-out embodiment 1 with lens error correction function of the present invention.

Fig. 2 is the explanation figure of the lens error correction according to barrel distortion of the image read-out embodiment 1 with lens error correction function of the present invention.

Fig. 3 is the explanation figure of the lens error correction according to pillow distortion of the image read-out embodiment 1 with lens error correction function of the present invention.

Fig. 4 is the circuit block diagram of the image read-out embodiment 2 with lens error correction function of the present invention.

Fig. 5 is the explanation figure according to readout clock and the lens error correction of the barrel distortion of benchmark coloured light or other coloured light of the image read-out embodiment 2 with lens error correction function of the present invention.

Fig. 6 is the explanation figure of the lens error correction of the pillow distortion according to readout clock and benchmark coloured light or other coloured light of the image read-out embodiment 2 with lens error correction function of the present invention.

Fig. 7 is the embodiment explanation figure of the digital filter bank of the present invention.

Detailed description of the invention

The present invention provides a kind of image read-out with lens error correction function, and described image read-out has: multiple line image sensors, and subject picture light is carried out light-to-current inversion respectively；And lens error correction unit, it is modified by the multiplying power chromatic aberration and distortion aberration that read the optical element that image is imaged on each line image sensor, wherein, can with the chromatic aberration that the delay digital filter bank correction in an only direction is produced by described optical element, distort aberration, according to reading the left and right of picture of image and gamut to the rgb signal that the different barrel distortion aberration of benchmark coloured light (or readout clock) lead-lag or pillow distorton aberration and the compound aberration distortion with multiplying power aberration distortion produce.

In figure, 1 is the image read-out with lens error correction function, 2 is optical element, 3 is line image sensor, 4 is S/H circuit, 5 is A/D translation circuit, 6 is that shade (shading) revises circuit, 7 is revise memorizer, 8 is lens error correction unit, 9 is R digital filter bank, 10 is B digital filter bank, 11, 12, 13 is FIFO memory, 14, 15, 16 is lead-out terminal, 17 is delay control unit, 18a is barrel distortion amending unit, 18b is barrel distortion correction memorizer, 19a is pillow distortion amending unit, 19b is pillow distortion correction memorizer, 20 is sensor driving unit, 21 is CPU, 22 is G digital filter bank.

[embodiment 1]

Embodiments of the invention 1 are the following image read-outs with lens error correction function, namely, at the multiplying power chromatic aberration caused by optical element, in the aberration distortion of the images such as the gamut that distortion aberration produces, measurement value based on each retardation between the image of benchmark coloured light and the image of other coloured light, the aberration distortion that the barrel distortion caused by optical element or pillow distortion cause produces contrary lead-lag to middle position and the middle position from picture to end of scan end from the scanning starting end of picture, and then, except described contrary aberration distortion, by controlling the delay digital filter bank in an only direction, the gamut between the reference colours light image of the multiplying power chromatic aberration generation caused by optical element and other coloured light image can also be revised.

In Fig. 1, there is the image read-out 1 of lens error correction function, be made up of following parts: the optical element 2 being representative with simple lens that subject is photographed；It is made up of the multiple pixels constituted with solid photographic element respectively, a direction configuration parallel to each other along the imaging surface of described optical element 2, is equipped with three line style line image sensors 3 of three RGB sensors to being carried out light-to-current inversion by the image of this optical element 2 imaging；Remove S/H (sampling/keep) circuit 4 from the intrinsic noise signal of the solid photographic element of picture signal of this line image sensor 3 output；A/D translation circuit 5 to the picture signal simulation/digital conversion eliminating described noise signal；Revise the shade correction circuit 6 of the shade of each picture signal after digital conversion and store the correction memorizer 7 having its correction；Lens error correction unit 8 (by two digital filter bank 9,10, barrel distortion amending unit 18a, barrel distortion correction memorizer 18b and pillow distortion amending unit 19a, pillow distortion correction memorizer 19b constitute)；FIFO (firstinfirstout) memorizer 11,12 and 13 of the picture signal of each of the picture signal storing the benchmark coloured light from the output of this lens error correction unit 8 and other coloured light that have modified aberration with the picture signal of this benchmark coloured light for benchmark；Export respectively from FIFO memory 11,12 and 13 read R, G, B signal lead-out terminal 14,15 and 16；Drive the sensor driving unit 20 of described line image sensor 3；And the CPU21 of each several part in control device.

It addition, described three line style line image sensors 3 are made up of red signal line image sensor 3r, green signal line image sensor 3g and blue signal line image sensor 3b.At this, as it is shown in figure 1, centered by green signal line image sensor 3g, be configured with red signal line image sensor 3r and blue signal line image sensor 3b at its two ends.

And then, described lens error correction unit 8 is made up of the R as digital filter bank (red) digital filter bank 9 constituted with multiple (being 6 in the present embodiment) digital filter and B (indigo plant) digital filter bank 10 and delay control unit 17, it is benchmark that described delay control unit 17 possesses G (green) signal to become reference colours light image, measurement value based on each retardation between the R signal of other chromasia and the image of B signal, control said two digital filter bank 9, the barrel distortion amending unit 18a of the filter coefficient of 10, barrel distortion correction memorizer 18b and pillow distortion amending unit 19a, pillow distortion correction memorizer 19b.

By subject is photographed with simple lens be representative the optical element 2 subject picture that is imaged on line image sensor 3 carried out light-to-current inversion by red signal line image sensor 3r, green signal line image sensor 3g and blue signal line image sensor 3b, remove, with respective S/H circuit 4, the noise that solid photographic element is intrinsic as R, G, B signal, it is simulated/digital conversion with A/D translation circuit 5, is input to shade correction circuit 6.

In described shade correction circuit 6, each correction memorizer 7 of the shading correction data by producing from the deviation of the brightness stored according to the difference of the line image respective sensory characteristic of sensor 3r, 3g and 3b, the illuminator of subject and imaging system etc. reads described shading correction data and carries out computing by each pixel, thus revising shade, it is input to lens error correction unit 8.

In described lens error correction unit 8, using the G picture signal as benchmark coloured light for benchmark, revise the R picture signal produced by the barrel distortion of described lens 2 or pillow distortion or multiplying power chromatic aberration and the B picture signal gamut relative to G picture signal.

It is connected with G lead-out terminal 15 from the G picture signal of described shade correction circuit 6 output via FIFO memory 12.

It addition, R picture signal is connected with R lead-out terminal 14 via R digital filter bank 9 and FIFO memory 11.

Similarly, B picture signal is connected with B lead-out terminal 16 via B digital filter bank 10 and FIFO memory 13.

Simultaneously, barrel distortion amending unit 18a it is input to respectively from each picture signal of RGB of described shade correction circuit 6 output, barrel distortion correction memorizer 18b and pillow distortion amending unit 19a, pillow distortion correction memorizer 19b, the correction signal of the gamut of the rgb signal that the barrel distortion different relative to benchmark coloured light lead-lag or pillow distortion and multiplying power aberration produce by the left and right of the picture according to reading image distorting aberration produced as described lens 2, from described barrel distortion amending unit 18a, barrel distortion correction memorizer 18b and pillow distortion amending unit 19a, pillow distortion correction memorizer 19b is respectively outputted to R digital filter bank 9 and B digital filter bank 10.

Described R digital filter bank 9 and B digital filter bank 10 are that low frequency passes through type (low pass) wave filter as wave filter kind, are made up of the unit delay digital filter with 7 taps that tap number is the degree that can meet frequency characteristic.In the present embodiment, illustrate as 6.

According to Fig. 2 and Fig. 3, the operation method due to the lens error correction of barrel distortion, pillow distortion and multiplying power aberration of the image read-out 1 with lens error correction function is described.

In figs. 2 and 3, white circle is denoted as the G pixel column of reference colours, and black circle represents R pixel column or B pixel column, and scanning direction represents with " ← scanning direction ".

About the pixel column represented with white circle, black circle, Fig. 2 (a) step S-0 represents the pixel column (before correction) before lens error correction, Fig. 2 (b) step S-1 is pixel column time (correction starts), and Fig. 2 (c) step S-2 represents the pixel column of (after correction).

Figure 2 illustrates following example, namely, in pixel column G, the R of (before the correction) of Fig. 2 (a) step S-0, picture transverse width relative to the image of described G pixel, the picture transverse width of the image of R pixel is subject to the impact of multiplying power aberration and broadens, but also it being subject to the impact of barrel distortion, the pixel of the left and right end of image deviates 1/2 amount of pixels.The numerical value 1 of pixel column, 2,3,4～n-3, n-2, n-1, n represent pixel number.

And, it is shown that following situation, i.e. the R pixel 1 of scanning starting end is the phase place of advanced 1/2 amount of pixels relative to G pixel 1, and the R pixel n of end of scan end is relative to the phase place that G pixel n is delayed 1/2 amount of pixels.

In (d) of Fig. 2, X direction represents picture width, y direction represents the R pixel lead-lag phase place relative to the zero phase level of G pixel, representing that the R pixel 1 scanning starting end of R pixel line is the phase position of advanced 1/2 amount of pixels upward relative to G pixel 1 when G pixel line is set to zero phase horizontal level, the R pixel n of the end of scan end of R pixel line is relative to the phase position that G pixel n is delayed 1/2 amount of pixels downwards.

The gradient of R pixel line slowly changes till playing the lagging phase position of end of scan end pixel from the leading phase position of scanning starting end pixel, almost without lead-lag near the central part of picture.

About described R pixel line, although represent by the gradient of straight line in easily understandable manner, but, this gradient and nonlinearity depend on multiplying power aberration/distortion aberration characteristic that the lens 2 as optical element have.

In described lens error correction unit 8, under the pixel column state of described Fig. 2 (a) step S-0 (before correction), with the pixel 1～n of the G picture signal of input for benchmark, these measurement data are written in barrel distortion correction memorizer 18b by the lead-lag amount of measurement R pixel 1～n.

Using the measurement value of this storage as measured value X.

Step S-1 (correction starts) position at (e) of Fig. 2 and the G/R' pixel column of Fig. 2 (b), described measurement data measured value X is read from described barrel distortion correction memorizer 18b, using delayed (1/2 amount of pixels) of R ' the pixel n of end of scan end as zero phase level so that it is consistent with the zero phase level of the G pixel n of end of scan end.

That is, in described lens error correction unit 8, it is programmed to following state, by CPU21 control, this state is, makes the G pixel n of the end of scan end of described G picture signal consistent with zero phase level with the R pixel n of the end of scan end of described R picture signal, and is read out when the end of scan simultaneously.

Then, the hysteresis of 1/2 amount of pixels of the R pixel n of end of scan end is added on the advanced argument of 1/2 amount of pixels of the R ' pixel 1 of scanning starting end.

Then, the hysteresis of R pixel n-1 is added on the advanced argument of R ' pixel 2, the correction value of whole R ' pixel column 1～n is made thereafter through same method, become the parallax R ' that the zero phase level from end of scan end image has been corrected successively, the correction value of these whole R ' pixel columns is written to described barrel distortion correction memorizer 18b.

Using the correction value of this storage as correction value Y.

Therefore, in the pixel column of Fig. 2 (b) step S-1 (correction starts) position, R ' the pixel 1 of scanning starting end adds the hysteresis of 1/2 amount of pixels of the R pixel n of Fig. 2 (a) step S-0 (before correction), becomes the state for advanced 1 amount of pixels of G pixel 1.

nullWhen so that the G pixel n of end of scan end of described G picture signal is consistent with zero phase level with the R pixel n of the end of scan end of described R ' picture signal and when that simultaneously read when end of scan mode programs and is controlled by CPU21，Described lens error correction unit 8，The correction value Y of described whole R ' pixel column 1～n is read from described barrel distortion correction memorizer 18b，Based on the correction value Y with the G pixel n of the described end of scan end described whole R ' pixel column 1～n being benchmark，Control described R digital filter bank 9 by the filter coefficient of 6 digital filters constituted，Thus，The pixel column R that Fig. 2 (c) step S-2 (after correction) represents " scanning starting end R pixel 1 controlled in the way of postponing an amount of pixels，Consistent with G pixel 1 phase place of the scanning starting end of G picture signal，The multiplying power chromatic aberration by described optical element can be revised or distort the gamut that aberration produces.

Namely, with the G pixel n of the end of scan end of described G picture signal for benchmark, first read out the correction value Y suitable by the R ' pixel 1 of 6 digital filters constituted with described R digital filter bank 9 in the correction value of described whole R ' pixel column 1～n, control the filter coefficient of described 6 digital filters according to this correction value Y.

As a result of which it is, described R can be made " pixel 1 postpones an amount of pixels, consistent with the phase place of the G pixel 1 of scanning starting end.Then, the pixel of R ' pixel 2 eliminates the delayed of each pixel also by the filter coefficient controlling described 6 digital filters.

By revised R " the R picture signal of pixel 1,2 is written to described FIFO memory 11.

Then, read the correction value Y of described whole R ' pixel columns of R ' pixel 3～n, to R ' the pixel n of end of scan end, performing to control the effect of filter coefficient of digital filter by each pixel successively, by revised R " picture signal is written to described FIFO memory 11.

Sequential read out the R being written to described FIFO memory 11 " picture signal, be corrected from R output signal terminal 14 output and eliminate the R of gamut " picture signal.

In figure 3, the example being shown below, namely, in the pixel column of the step S-0 (before correction) before Fig. 3 (a) revises, picture transverse width relative to the image of described G pixel, the picture transverse width of the image of B pixel is subject to the impact of multiplying power aberration and narrows, but also is subject to the impact of pillow distortion, and the pixel of the left and right end of picture deviates 1/2 amount of pixels.The numerical value 1 of pixel column bottom, 2,3,4～n-3, n-2, n-1, n represent pixel number.

And, it is shown that following situation, i.e. the B pixel 1 of scanning starting end is the phase place of delayed 1/2 amount of pixels relative to G pixel 1, and the B pixel n of end of scan end is relative to the phase place that G pixel n is advanced 1/2 amount of pixels.

Situation following shown in (d) of Fig. 3, namely, X direction represents picture width, y direction represent B pixel relative to G pixel delayed/leading phase, when using G pixel line as zero phase horizontal level, the B pixel 1 of the scanning starting end of B pixel line is the phase position relative to G pixel 1 delayed 1/2 amount of pixels downwards, and the B pixel n of the end of scan end of B pixel line is the phase position relative to G pixel n advanced 1/2 amount of pixels upward.

The gradient of B pixel line 1～n slowly changes to the leading phase position of the B pixel n of end of scan end from the lagging phase position of the B pixel 1 of scanning starting end, almost without lead-lag near the central part of picture.

Although described B pixel line represents by the gradient of straight line in easily understandable manner, but, this gradient and nonlinearity depend on multiplying power aberration/distortion characteristic that the lens 2 as optical element have.

Described lens error correction unit 8 is under the pixel column state of described Fig. 3 (a) step S-0 (before correction), with the G pixel 1～n of the G picture signal of input for benchmark, measurement B pixel 1～n delayed/advanced argument, these measurement data are written to pillow distortion correction memorizer 19b.

Using the measurement value of this storage as measured value X '.

In step S-1 (correction starts) position of the G/B' pixel column of Fig. 3 (b), read described measurement data measured value X ' from described pillow distortion correction memorizer 19b, advanced (1/2 amount of pixels) of the B pixel n of end of scan end is added in the level of B ' pixel 1 of scanning starting end image.

Namely, it is consistent with zero phase level with the picture position of the B pixel 1 of the scanning starting end of described B ' picture signal that described lens error correction unit 8 is programmed to the G pixel 1 making the scanning starting end of described G picture signal, and the state simultaneously read when scanning starts, CPU21 it is controlled.

Then, the hysteresis of 1/2 amount of pixels of the B pixel 1 of scanning starting end is added on the advanced argument of 1/2 amount of pixels of the B pixel n of end of scan end.

Additionally, the hysteresis of B pixel 2 is added on the advanced argument of B pixel n-1, the correction value of whole B ' pixel columns of pixel 1～n is made thereafter through same method, become the parallax B ' that the zero phase level from scanning starting end be have modified successively, the correction value of these whole B ' pixel columns is written to described pillow distortion correction memorizer 19b.

Using the correction value of this storage as correction value Y '.

Therefore, as shown in the pixel column of Fig. 3 (b) step S-1 (correction starts) position and Fig. 3 (e), B ' the pixel n of end of scan end is coupled with the hysteresis of 1/2 amount of pixels of the B pixel 1 of the step S-0 (before correction) of the scanning starting end of Fig. 3 (a), becomes the state of super previous amount of pixels.

nullWhen so that the B ' pixel 1 of scanning starting end of the scanning G pixel 1 of starting end of described G picture signal and described B ' picture signal is consistent with zero phase level and when that simultaneously read when scanning beginning mode is programmed and is controlled by CPU21，Described lens error correction unit 8 reads the correction value Y ' of described whole B ' pixel columns from described pillow distortion correction memorizer 19b，Correction value Y ' based on described whole B ' pixel columns that the G pixel 1 of the scanning starting end with described G picture signal is benchmark，Control described B digital filter bank 10 by the filter coefficient of 6 digital filters constituted，Thus，As the pixel column illustrated in Fig. 3 (c) step S～2 (after correction)，The B of end of scan end " pixel n controlled in the way of postponing an amount of pixels，Consistent with the G pixel n phase place of the end of scan end image of G picture signal，The chromatic aberration by described optical element can be revised or distort the gamut that aberration produces.

Namely, with the G pixel 1 of the scanning starting end of described G picture signal for benchmark, first read out the correction value Y ' suitable by the B pixel n of 6 digital filters constituted with described B digital filter bank 10 in the correction value of described whole B ' pixel column, control the filter coefficient of described 6 digital filters according to this correction value Y '.

Its result is, described B can be made " pixel n postpones an amount of pixels and consistent with the phase place of the G pixel n of end of scan end; then, add the B of the hysteresis of the B ' pixel 2 of scanning starting end " pixel of pixel n-1 is also by controlling the filter coefficient of described 6 digital filters to eliminate the delayed of each pixel.

The B of delayed described Fig. 3 (c) step S-2 (after correction) of pixel being eliminated with G pixel 1 for benchmark " picture element signal of pixel 1,2 is written to described FIFO memory 13.

Then, read B equally " the correction value Y ' of described whole B ' pixel columns of pixel less than 3; to the B of end of scan end " perform to control the effect of the filter coefficient of digital filter successively by each pixel pixel n-2, by revised B " picture signal is written to FIFO memory 13.

Sequential read out the B being written to described FIFO memory 13 " picture signal, can be corrected from B output signal terminal 16 output and eliminate the B of gamut " picture signal.

Therefore, described lens error correction unit 8, repeat the operation of the correction value of the described hysteresis that each memorizer at described barrel distortion correction memorizer 18b and pillow distortion correction memorizer 19b writes and the respective multiple digital filter numbers of described digital filter bank 9 and 10 are suitable of whole amount of pixels, the filter coefficient of multiple digital filters of described digital filter bank 9 and 10 is controlled based on the correction value of the whole amount of pixels sequential read out, energy revises the gamut of the whole images caused by the aberration distortion caused by described optical element 2 of the pixel R/B of other coloured light relative to the pixel G of benchmark coloured light.

[embodiment 2]

Embodiments of the invention 2 are the image read-outs with lens error correction function, compare that interval is accurate and the image picture of W (RGB) picture signal of undistorted pixel readout clock and benchmark coloured light or the white light as other coloured light in electricity mode, revise the chromatic aberration caused by optical element or distort the aberration distortion of the described W picture signal that aberration produces, the RGB image signal entirely without aberration distortion can be obtained.

In the diagram, G digital filter bank 22 is added at the circuit block diagram of the embodiment 1 of Fig. 1.

According to Fig. 4～Fig. 6, the operation method due to the lens error correction of barrel distortion, pillow distortion and multiplying power aberration of the embodiment 2 of the image read-out 1 with lens error correction function is described.

Additionally, about basic structurally and functionally because in accordance with embodiment 1, thus omit, be defined in the narration about additional G digital filter bank 22.

In fig. 5 and fig., white circle represents the pixel readout clock of described line image sensor, and black circle is denoted as the W pixel of R, G and B pixel, and scanning direction represents with " ← scanning direction ".

About the clock C represented with white circle, black circle and W pixel column, Fig. 5 (a) represents the step S-0 (before correction) before lens error correction, when the step S-1 of Fig. 5 (b) is (correction starts), Fig. 5 (c) represents the step S-2 (after correction) after lens error correction.

Figure 5 illustrates following situation, namely, in the clock C and pixel column W of Fig. 5 (a) step S-0 (before correction), as valid pixel width～carry out with the causing imaging of image and described line image sensor 3 of the W image of described white light, and it is subject to the multiplying power chromatic aberration of optical element 2 and tubbiness distorts aberration.

The example being shown below, namely, relative to reading from the scanning starting end of the image of described W picture signal to the transverse width of the readout clock C of the line image sensor of end of scan end, the picture transverse width of the image of W pixel is subject to the impact of multiplying power aberration and broadens, but also be subject to tubbiness and distort the impact of aberration, the pixel of the left and right end of picture deviates 1/2 amount of pixels.

White circle, the numerical value 1 of black circle row bottom, 2,3,4～n-3, n-2, n-1, n represent block number and pixel number respectively.

And, it is shown that following situation, i.e. the W pixel 1 of scanning starting end is the phase place relative to advanced 1/2 amount of pixels of described readout clock C1, and the W pixel n of end of scan end is the phase place of 1/2 amount of pixels delayed relative to readout clock Cn.

Situation about being shown below, in (d) of Fig. 5, X direction represents picture width, y direction represents the W pixel lead-lag phase place relative to readout clock C, when using readout clock C line as zero phase horizontal level, the W pixel 1 of the scanning starting end of W pixel line is the phase position of advanced 1/2 amount of pixels upward relative to readout clock C1, and the W pixel n of the end of scan end of W pixel line is the phase position relative to clock Cn delayed 1/2 amount of pixels downwards.

The gradient of the W pixel line lagging phase position from the leading phase position of scanning starting end to end of scan end slowly changes, almost without lead-lag near the central part of picture.

Although described W pixel line represents by the gradient of straight line in easily understandable manner, but, this gradient and nonlinearity depend on multiplying power aberration/distortion aberration characteristic that the lens 2 as optical element have.

Described lens error correction unit 8 is under the pixel column state of described Fig. 5 (a) step S-0 (before correction), with reading from the scanning starting end of the image of described W image to the readout clock pixel column C1～n of the line image sensor of end of scan end for benchmark, these measurement data are written to barrel distortion correction memorizer 18b by the lead-lag amount of measurement W pixel 1～n.

Using the measurement value of this storage as measured value U.

In step S-1 (correction starts) position of (e) of Fig. 5 and the C/W' pixel column of Fig. 5 (b), described measurement data measured value U is read from described barrel distortion correction memorizer 18b, using delayed 1/2 amount of pixels of the pixel Wn of end of scan end as zero phase level so that it is consistent with the zero phase level of the readout clock n of end of scan end.

That is, described lens error correction unit 8 is programmed to make the pixel Wn of the end of scan end of readout clock Cn and the W picture signal of described end of scan end consistent with zero phase level and state that is that simultaneously read when the end of scan, CPU21 be controlled.

Then, the hysteresis of 1/2 amount of pixels of the pixel Wn of end of scan end is added on the advanced argument of 1/2 amount of pixels of the W ' pixel 1 of scanning starting end.

Then, the hysteresis of pixel Wn-1 is added on the advanced argument of W ' pixel 2, the correction value V of whole W ' pixel columns of pixel 1～n is made thereafter through same method, become the parallax W ' that the zero phase level from end of scan end is corrected successively, the correction value V of these whole pixel column W ' is written to described barrel distortion correction memorizer 18b.

Therefore, in the pixel column of Fig. 5 (b) step S-1 (correction starts) position, W ' the pixel 1 of scanning starting end has been coupled with the hysteresis of 1/2 amount of pixels of Fig. 5 (a) step S-0 (before correction) the pixel Cn of end of scan end, becomes the state of advanced 1 amount of pixels.

nullWhen so that the pixel W'n of end of scan end of described W ' picture signal is consistent with zero phase level with the readout clock Cn of described end of scan end and when that simultaneously read when end of scan mode is programmed and is controlled by CPU21，Described lens error correction unit 8 reads the correction value V of described whole pixel column W ' from described barrel distortion correction memorizer 18b，Correction value V based on the pixel n of the end of scan end with the described W picture signal described whole pixel column W ' being benchmark，Control described digital filter bank 9、22 and 10 by the filter coefficient of 6 digital filters constituted，Thus，As Fig. 5 (c) step S-2 (after correction) pixel column illustrated，W " the pixel W of scanning starting end of picture signal " l controlled in the way of postponing an amount of pixels，Consistent with the readout clock C1 phase place of described scanning starting end，Can revise by the chromatic aberration of described optical element、Distort the gamut that aberration produces.

Namely, pixel W with the end of scan end of described W picture signal " n is for benchmark; first read out the correction value V suitable by the pixel 1 of 6 digital filters constituted with described each digital filter bank in the correction value of described whole pixel column W ', control the filter coefficient of described 6 digital filters according to this correction value V.

As a result of which it is, described W can be made " the stagnant later amount of pixels of pixel 1 is consistent with the phase place of scanning starting end readout clock C1.Then, the pixel of W ' pixel 2 eliminates the delayed of each pixel also by the filter coefficient controlling described 6 digital filters.

By revised W " the W picture signal of pixel 1,2 is written to described FIFO memory 12.

Then, reading the later correction value V of W ' pixel 3, perform successively to control the G effect of the filter coefficient of digital filter bank 22 to the pixel W'n of end of scan end, by revised W " picture signal is written to described FIFO memory 12.

Sequential read out the W being written to described FIFO memory 12 " picture signal, can be corrected from G output signal terminal 15 output and eliminate the W as R, G and B picture signal of gamut " picture signal.

In figure 6, situation about being shown below, namely, in the pixel column of the step S-0 (before correction) before Fig. 6 (a) revises, as image imaging in the way of inconsistent with the valid pixel width of described line image sensor of the W picture signal of described R, G and B picture signal, and it is subject to the multiplying power chromatic aberration of optical element and pillow distorts aberration.

Additionally, the example being shown below, namely, relative to reading from the scanning starting end of the image of described W pixel to the transverse width of the readout clock pixel column C of the line image sensor of end of scan end, the picture transverse width of the image of W pixel is subject to the impact of multiplying power aberration and narrows, but also be subject to pillow and distort the impact of aberration, the pixel of the left and right end of picture deviates 1/2 amount of pixels.

White circle, the numerical value 1 of black circle row bottom, 2,3,4～n-3, n-2, n-1, n represent clock number and pixel number respectively.

And, it is shown that following situation, i.e. the pixel W1 of scanning starting end is the phase place of delayed 1/2 amount of pixels relative to readout clock C1, and the pixel Wn of end of scan end is relative to the phase place that readout clock is advanced 1/2 amount of pixels.

In Fig. 6 (d), situation about being shown below, namely, X direction represents picture width, y direction represent W pixel relatively and readout clock C delayed/leading phase, when using readout clock line C as zero phase horizontal level, the W pixel 1 of the scanning starting end of W pixel line is the phase position relative to readout clock C1 delayed 1/2 amount of pixels downwards, and the pixel Wn of the end of scan end of W pixel line is the phase position relative to readout clock advanced 1/2 amount of pixels upward.

The gradient of the pixel line W leading phase position from the lagging phase position of scanning starting end to end of scan end slowly changes, almost without lead-lag near the central part of picture.

Although described W pixel line represents by the gradient of straight line in easily understandable manner, but, this gradient and nonlinearity depend on multiplying power aberration/distortion characteristic that the lens 2 as optical element have.

Described lens error correction unit 8 is under the pixel column state of described Fig. 6 (a) step S-0 (before correction), with reading from the scanning starting end of the image of described W pixel to the readout clock C of the line image sensor of end of scan end for benchmark, measurement pixel W1～n delayed/advanced argument, this measurement data measured value is written to the memorizer of pillow distortion correction memorizer 19b.

Using the measurement value of this storage as measured value U '.

In step S-1 (correction starts) position of C/W' pixel column and Fig. 6 (e) of Fig. 6 (b), the measured value U ' of described measurement data is read from described pillow distortion correction memorizer 19b, using delayed 1/2 amount of pixels of the pixel W1 of scanning starting end as zero phase level so that it is consistent with the zero phase level of the readout clock 1 of scanning starting end.

That is, described lens error correction unit 8 is programmed to make the pixel W ' 1 of the scanning starting end of described W picture signal consistent with zero phase level with the readout clock C1 of described scanning starting end and state that is that simultaneously read when scanning beginning, and is controlled by CPU21.

Then, the hysteresis of 1/2 amount of pixels of the pixel W1 of scanning starting end is added on the advanced argument of 1/2 amount of pixels of the pixel Wn of end of scan end.

Additionally, the hysteresis of pixel W2 is added on the advanced argument of pixel Wn-1, the correction value V ' of whole pixel column W ' of pixel 1～n is made thereafter through same method, become the parallax W ' that the zero phase level from scanning starting end is corrected successively, the correction value V ' of these whole pixel column W ' is written to described pillow distortion correction memorizer 19b.

Therefore, in the pixel column of Fig. 6 (b) step S-1 (correction starts) position, W ' the pixel n of end of scan end is coupled with the hysteresis of 1/2 amount of pixels of Fig. 6 (a) step S-0 (before correction) the pixel W1 of scanning starting end, becomes the state of super previous amount of pixels.

nullWhen so that the pixel W ' 1 of scanning starting end of described readout clock C1 and described W ' picture signal is consistent with zero phase level and when that simultaneously read when scanning beginning mode is programmed and is controlled by CPU21，Described lens error correction unit 8 reads the correction value V ' of described whole pixel column W ' from described pillow distortion correction memorizer 19b，Correction value V ' based on the pixel W ' 1 of the scanning starting end with the described W picture signal described whole pixel column W ' being benchmark，Control described digital filter bank 9、22 and 10 by the filter coefficient of 6 digital filters constituted，Thus，As Fig. 6 (c) step S-2 (after correction) pixel column illustrated，W " the pixel W of end of scan end of picture signal " n controlled in the way of postponing an amount of pixels，Consistent with the pixel Cn phase place of described end of scan end clock C，Can revise by the chromatic aberration of described optical element 2、Distort the gamut that aberration produces.

Namely, with described W " the pixel W1 of the scanning starting end of picture signal is for benchmark; first read out the correction value V ' suitable by the pixel W ' 1,2 of 6 digital filters constituted with described each digital filter bank in the correction value of described whole W ' pixel column, control the filter coefficient of described 6 digital filters according to this correction value V '.

As a result of which it is, described pixel W can be made " n postpones an amount of pixels and consistent with the phase place of the readout clock Cn of end of scan end, then, pixel W " 2 eliminate the delayed of each pixel also by the filter coefficient of described 6 digital filters of control.

Pixel W by described Fig. 6 (c) step S-2 (after correction) " 1,2 picture element signal be written to described FIFO memory 12.

Then, read pixel W " the correction value V ' of 3 later described whole W ' pixel columns; to the pixel W of end of scan end " it is repeated in controlling the effect of the filter coefficient of G digital filter bank 22 n, by revised W " picture signal is written to described FIFO memory 12.

Additionally, as other method, the also described pixel column W have modified aberration exactly for clock row C " in G " 1～n is for benchmark, revise the described pixel column R of described pixel column R1～n and pixel column B1～n or step S-2 (after correction) of step S-0 (before correction) " 1～n and pixel column B " aberration of 1～n, thus, the image of aberration can be have modified completely.

Other than the above structurally and functionally in accordance with embodiment 1.

Fig. 7 is the embodiment explanation figure of the digital filter of the lens error correction unit constituting the present invention, Fig. 7 (a) is in benchmark coloured light (G) and other coloured light digital filter bank shared in (R, B), and Fig. 7 (b) is enter into the explanation figure of an example of the filter coefficient G1～G49 of the filter coefficient input K0～K6 of Fig. 7 (a).

At this, to structurally and functionally illustrating of this digital filter bank when being applied to the image read-out employing the line image sensor of valid pixel number 4096.

In Fig. 7 (a), about by R, G, the digital filter bank 9 (R uses) being made up of multiple digital filters of each arranging of the white light of B, 22 (G uses), 10 (B uses), in the picture output signal by digital signalization of the described line image sensor 3 that read by pixel readout clock, by controlling the filter coefficient of described digital filter respectively, it is thus possible to the pixel correction of each picture signal of other coloured light (or benchmark coloured light) becoming leading phase relative to the picture signal (or pixel readout clock) of described benchmark coloured light by the chromatic aberration of described optical element, distort the gamut that aberration produces.

Described R digital filter bank 9, G digital filter bank 22 and B digital filter bank 10 are made up of the digital filter of 7 taps of the delay of (or more than 1 pixel) within controlling 1 pixel.

Described digital filter bank 9,22 and 10 is FIR filter (finite impulse response filter), D1～D6 is unit delay digital filter, K0～K6 is filter coefficient input, white circle with X is filter coefficient setting depositor (multiplier), band+white circle be adder, IN (n) represents that picture signal inputs, and OUT (n) represents that picture signal exports.

At this, 1 tap is constituted by each one of described unit delay digital filter, multiplier and adder.

Additionally, foregoing circuit is made up of DSP (DigitalSignalProcessor: digital signal processor) such as FPGA (FieldprogrammableGateArray: field programmable gate array) or ASIC (ApplicationSpecificIntegratedCircuit: special IC).

In the present embodiment, in order to utilize the well-known digital filter design instrument of FIR filter to obtain characteristic, need to design the initial conditions of this design tool, first, type as wave filter is set to low frequency by type (low pass) wave filter, tap number is set to 7 taps (K0～K6) with the degree that can meet frequency characteristic, and the window function that selected phase distortion is low.

Additionally, the maximum of filter coefficient is set to 2¹⁴(16384), cut-off frequency is set to the 40MHz of the 1/2 of pixel readout clock frequency 80MHz, and the minimum phase systems amount of pixel is set to the 0～1/16 of pixel separation, additionally, total pixel number 4096 is divided into 128 collection, carries out phase controlling uniformly as 32 pixels/collection.

Under above initial conditions, utilize described digital filter design instrument, control digital filter bank 9,22 and 10.

Its result is, under pixel column state before correction, described lens error correction unit 8 reads the described measured value X according to the lead-lag amount surveying R/B pixel column 1～n (or surveying G pixel column 1～n in reference count for readout clock C row 1～n) in reference count for G pixel column 1～n from barrel distortion correction memorizer 18b (or pillow distortion correction memorizer 19b), X ' (or U, U ') the described correction value Y that obtains, Y ' (or V, V '), it is input to each multiplier, described correction value Y according to input, Y ' (or V, V ') by the filter coefficient setting depositor K0～K6 of 7 taps, control the phase place within 1 pixel in the present embodiment.

Such as, when the line image sensor of total pixel number 4096 dot structure, 17 filter coefficient setting value concentrating 7 taps preserving control K0～K6 that the memorizer of described barrel distortion correction memorizer 18b (or pillow distortion correction memorizer 19b) collects in 32 pixel × 128.

It addition, CPU21 preserves the filter coefficient consistent with the phase settings of the correction value Y of leading phase, Y ' (V, V ') at described barrel distortion correction memorizer 18b (or pillow distortion correction memorizer 19b).

In real screen, it is configured to correction value Y, Y ' (or V, V ') according to recalling from described memorizer and updates 1 filter coefficient collected by 32 pixels, thus, No. 1 pixel～No. 32 pixel filter coefficient of the 1st collection is controlled, then, No. 33 pixel～No. 64 pixel filter coefficient of the 2nd collection is controlled.

Therefore, prepare the filter coefficient of the amount of 32 pixel × 128 collection, 4096 pixels can be tackled all.

Or, the pixel count of the collection unit of described integer divides can also be controlled as follows, that is, the region distorting aberration little near imaging picture central authorities makes 1 pixel count collect increase, along with near picture central authorities close to scanning starting end or end of scan end makes 1 pixel count collected tail off.

Or, as described about embodiment 1 and embodiment 2, it is also possible to control filter coefficient according to the correction value of each pixel.

The filter coefficient setting value of the digital filter of the correction value Y, the Y ' that read from described barrel distortion correction memorizer 18b (or pillow distortion correction memorizer 19b) (or V, V '), numbered by input set or pixel number (No. 1～No. 4096) and automatically read, can switching filter characteristic successively, export OUT (n) output from signal and be delayed by and control the picture output signal without gamut.

Fig. 7 (b) is an example of the input method of the filter coefficient of the K0～K6 of the delay within 1 pixel of control of Fig. 7 (a), using 32 pixels as 1 collection, with row unit until Set1～Set7 ... Set128 input filter coefficient, revise the multiplying power chromatic aberration of the whole amount of pixels caused by optical element 2 and distort aberration.

Described filter coefficient input K0～K6, controls with the filter coefficient G1～G7/G8～G14//G890～G896 (7 × 128 collection) of each collection obtained according to described correction value Y, Y ' (or V, V ').

At this, it is connected to various image analysis apparatus, FA (factory automation) measuring device etc. at output end of image 14,15 and 16, can with have modified optical element chromatic aberration distortion, distort aberration distortion without gamut image export be driven, therefore, add that the high-accuracy line image sensor of use can carry out high-precision measurement, graphical analysis.

Although employing 3 line style line image sensors in described each embodiment, but, can also be the structure being combined with the chromatic resolution optical systems such as prism and multiple high-resolution monochrome mode line image sensor in addition.

Alternatively, it is also possible to be the camera style being combined with 1 high-resolution monochrome mode line image sensor with the face sequential system of the illuminator using the light emitting diode etc. sending RGB color successively.

In any of the above-described kind of mode, as long as the signal of video signal carrying out light-to-current inversion by line image sensor and obtaining is R, G, B three primary colors mode.

Industrial applicability

A kind of image read-out with lens error correction function, there are multiple line image sensors that subject picture light carries out light-to-current inversion respectively and the lens error correction unit of the optical element that image is imaged on each line image sensor will be read, wherein, described lens error correction unit is being subject to the chromatic aberration that optical element has, when distorting the impact of aberration and make the picture transverse width of the image of other coloured light broaden relative to the picture transverse width of the image of described benchmark coloured light or the time of narrowing, the central authorities from the scanning starting end of the image produced to picture, the delayed/advanced of pixel contrary respectively can be produced from picture central authorities to end of scan end, but, the digital filter in an only direction can be utilized to revise by chromatic aberration when switching and switch over, distort the gamut that aberration produces.

Description of reference numerals

1: there is the image read-out of lens error correction function；

2: optical element；

3: line image sensor；

4:S/H circuit；

5:A/D translation circuit；

6: shade correction circuit；

7: revise memorizer；

8: lens error correction unit；

9:R digital filter bank；

10:B digital filter bank；

11,12,13:FIFO memorizer；

14,15,16: lead-out terminal；

17: delay control unit；

18a: barrel distortion amending unit；

18b: barrel distortion correction memorizer；

19a: pillow distortion amending unit；

19b: pillow distortion correction memorizer；

20: sensor driving unit；

21:CPU；

22:G digital filter bank.

Claims

1. there is an image read-out for lens error correction function, have: multiple line image sensors, subject picture light is carried out light-to-current inversion respectively；And lens error correction unit, to will read the multiplying power chromatic aberration of the image optical element that is imaged on each line image sensor and distort at least any of aberration of aberration and be modified, described in there is the image read-out of lens error correction function be characterised by,

Described lens error correction unit possesses:

Digital filter bank, it is made up of multiple digital filters, input the digitized picture signal of carrying out reading image of described line image sensor, by one of multiple coloured light being controlled using the time delay that the aberration by described optical element causes of each reading image of described line image sensor as benchmark coloured light, using remaining coloured light as other coloured light, described digital filter bank arranges respectively for this other coloured light；

In described delay control unit,

2. there is an image read-out for lens error correction function, have: multiple line image sensors, subject picture light is carried out light-to-current inversion respectively；And lens error correction unit, to will read the multiplying power chromatic aberration of the image optical element that is imaged on each line image sensor and distort at least any of aberration of aberration and be modified, described in there is the image read-out of lens error correction function be characterised by,

Described lens error correction unit has:

In described delay control unit,

3. the image read-out with lens error correction function according to claim 1 and 2, it is characterised in that

Described lens error correction unit is by sequential reading out the filter coefficient that the measurement value of the described retardation being stored in described memorizer controls the digital filter bank of each arranging by the plurality of coloured light, it is thus possible to output have modified the picture signal of aberration continuously.

4. the image read-out with lens error correction function according to any one of claim 1～2, it is characterised in that

Described lens error correction unit the integer of whole pixel counts of described line image sensor is divided one pixel count as a collection, control filter coefficient collecting unit, revise the gamut produced by the aberration distortion that caused by described optical element.

5. the image read-out with lens error correction function described in any one according to claim 4, it is characterised in that

Control the pixel count of the collection unit of described integer divides as follows, i.e. the region distorting aberration little near imaging picture central authorities makes pixel count increase, along with making pixel count reduce close to scanning starting end or end of scan end near picture central authorities.

6. the image read-out with lens error correction function according to any one of claim 1～2, it is characterised in that

Described reference colours just green light, other coloured light described is red light and blue light.