JPH0865450A - Image reading device, image reading method, and imaging device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an image reading device in which color mixing is less likely to occur even when a linear image sensor in which charge transfer units are arranged with light receiving units of different colors interposed therebetween is used. [Structure] A plurality of image line sensors 301, 302, 303 provided with color filters of a plurality of colors, and transfer units 304 to 3 for transferring charges from the image line sensors.
09, and the charges received and accumulated by the image line sensor 302 of at least one color are transferred to the transfer unit 306,
Upon being sent to the image line sensor 307, the linear image sensor configured to go through the image line sensor 303 of the other color and the electric charge that has passed through the image line sensor 303 of the other color, the light is received by the image line sensor 303 of the other color, And a subtraction circuit for subtracting the accumulated charge multiplied by the correction coefficient.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading device, an image reading method and an image pickup device, and more particularly to an image reading device and an image reading method using a linear image sensor for performing an intra-pixel transfer read operation.

[0002]

2. Description of the Related Art Conventionally, as a color image reading apparatus using a linear image sensor, one having a structure shown in FIG. 6 has been known. In the color image reading apparatus of FIG. 6, the original 212 on the original table glass 211 is illuminated by the light source 2 for illumination.
10 and the reflection shade 209 to illuminate the reflected light from the original,
First mirror 208, second mirror 205, third mirror 20
An image is formed on the light receiving surface of the CCD (color linear image sensor) 201 by the lens 6 and the lens 202. Further, in FIG. 6, a portion indicated by a broken line 207 is moved at a speed V in the arrow direction in the drawing, and a portion indicated by a broken line 203 is moved at a speed V / 2 in the arrow direction in the drawing, whereby an image of the entire original 212 is obtained. Can be read by the CCD 201.

FIG. 7 is a diagram showing a configuration example of a CCD linear image sensor 201 used in a conventional color image reading apparatus. In FIG. 7, 301, 302, 30
Reference numeral 3 is a light receiving portion having color filters of R (red), G (green) and B (blue). In this light receiving portion, a diode for converting a photon into an electric charge (electron) is arranged for each pixel. The light received for a predetermined time and the electric charge generated by the light reception are CCDs for ODD pixels
Transfer units (charge transfer units) 304, 306, 308, and E
CCD transfer unit (charge transfer unit) 305, 3 for VEN pixels
It is transferred (shifted) to 07,309. The charges transferred (shifted) to the CCD transfer unit are sequentially transferred in a fixed direction in the CCD transfer unit while the light receiving unit is receiving and accumulating the next line, and sequentially transferred by the amplifiers 310 to 316. It is converted into a signal and output.

[0004]

However, as shown in FIG. 7, the conventional color linear image sensor has a CCD transfer unit for transferring charges between the R, G and B light receiving units. Therefore, it is necessary to set a large distance between the R and G light receiving portions and a distance between the G and B light receiving portions shown in FIG.

When the distance between the light receiving portion and the light receiving portion is widened, when the read R, G, B signals are subjected to color correction processing such as masking calculation, a memory for correcting the read position of the R, G, B signals is provided. Although required, there is a problem in that the larger the R, G, B interval, the larger the required memory capacity. However, recently, a structure has been proposed in which the CCD transfer section is not adjacent to the light receiving section, but the light receiving sections of different colors are arranged in between.

FIG. 8 shows a configuration example in which the CCD transfer section is arranged with the light receiving sections of different colors interposed therebetween. In this case, since it is not necessary to dispose the CCD transfer unit between the light receiving units of the respective colors, the interval between the R, G, and B light receiving units can be significantly reduced as compared with the conventional sensor, and the required memory is required. The capacity is small. However, on the other hand, the charge received and accumulated is C
In order to transfer (shift) to the CD transfer section, it is necessary to go through the light receiving sections (pixels) of different colors. When this so-called intra-pixel transfer is performed, the light receiving section receives the reflected light from the original image even when passing through the light receiving sections of different colors, so that a slight color mixing occurs during the transfer. There is a point.

Therefore, the present invention has been made in view of the above problems, and an object thereof is to use a linear image sensor in which a charge transfer section is arranged with light receiving sections of different colors interposed therebetween. An object of the present invention is to provide an image reading device and an image reading method in which color mixing is less likely to occur.

[0008]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, the image reading device of the present invention comprises
In an image reading device that reads a color image by scanning a document in the main scanning direction and the sub-scanning direction while irradiating light, and photoelectrically converting the reflected light reflected from the document using an image line sensor, A plurality of image line sensors each provided with a filter, and a transfer unit arranged on both sides in the width direction of the plurality of image line sensors for transferring charges from the image line sensors, and at least one color The electric charge received and accumulated by the image line sensor of 1 is transmitted to the transfer unit by a linear image sensor configured to pass through an image line sensor of another color and an image line sensor of another color. The charge received and accumulated by the image line sensor of the other color is multiplied by the correction coefficient. It is characterized by having a subtraction means for subtracting.

Further, in the image reading apparatus according to the present invention, the multiplication of the correction coefficient and the subtraction of the electric charge multiplied by the correction coefficient are performed prior to normalization with respect to the reference white. Further, in the image reading device according to the present invention, the correction coefficient includes a time required for passing charges, a time required for transferring charges from an image line sensor of a color through which the charges are transferred to the transfer unit, and It is characterized by being a constant that is uniquely determined from the accumulation time.

Further, in the image reading apparatus according to the present invention, the image line sensor provided with a memory for at least one line passes through the charge, and the charge of the two pixels before and after the charge transfer, The correction coefficient is at least two types of constants determined for each of the charges of the two pixels.

Further, in the image reading apparatus according to the present invention, the time required for passing the charges is ΔT2, the time required for transferring the charges from the image line sensor passing through to the transfer unit is ΔT1, and the charge accumulation time is Assuming T, the correction coefficient is − (ΔT2 + ΔT1) / (T + Δ
It is characterized by being represented by T1). Further, in the image reading apparatus according to the present invention, the correction coefficient applied to the charges of the two pixels before and after the charge transfer is −ΔT 2 /
It is characterized by being expressed by (T + ΔT1) and -ΔT1 / (T + ΔT1).

According to the image reading method of the present invention, the document is scanned in the main scanning direction and the sub-scanning direction while irradiating light,
In an image reading method for reading a color image by photoelectrically converting reflected light reflected from an original using an image line sensor, a plurality of image line sensors each provided with a color filter of a plurality of colors, and the plurality of image line sensors And a transfer unit for transferring the charge from the image line sensor, which is disposed on both sides in the width direction of the image line sensor, and the charge received and accumulated by the image line sensor of at least one color is sent to the transfer unit. In this case, a linear image sensor configured to pass through the image line sensor of another color is provided, and light is received and accumulated by the image line sensor of the other color from the charge that has passed through the image line sensor of the other color. It is characterized by subtracting the product of the generated charge and the correction coefficient.

Further, in the image reading method according to the present invention, the multiplication of the correction coefficient and the subtraction of the charges multiplied by the correction coefficient are performed prior to normalization with respect to the reference white. Further, in the image reading method according to the present invention, the correction coefficient is defined as a time required to transfer charges, a time required to transfer the charges from the image line sensor of a color through which the charges are transferred to the transfer unit, and It is characterized by being a constant that is uniquely determined from the accumulation time.

Further, in the image reading method according to the present invention, the image line sensor provided with a memory for at least one line passes through the charge, and the charge of the two pixels before and after the charge transfer, The correction coefficient is at least two types of constants determined for each of the charges of the two pixels.

Further, in the image reading method according to the present invention, the time required for the passage of charges is ΔT2, the time required for transferring the charges from the image line sensor passing therethrough to the transfer section is ΔT1, and the charge accumulation time is Assuming T, the correction coefficient is − (ΔT2 + ΔT1) / (T + Δ
It is characterized by being represented by T1). Further, in the image reading method according to the present invention, the correction coefficient applied to the charges of the two pixels before and after the charge transfer is −ΔT 2 /
It is characterized by being expressed by (T + ΔT1) and -ΔT1 / (T + ΔT1).

Further, the image pickup device of the present invention is arranged such that the first light receiving sensor, the second light receiving sensor, and the side opposite to the first light receiving sensor near the second light receiving sensor, Transfer means for reading the charges of the first and second light receiving sensors, and a charge signal of the second light receiving sensor are read out through the transfer means, and the charge signal of the first light receiving sensor is read. Control means for reading out via the transfer means after transferring to the transfer means via the second light receiving sensor, and signals of the first and second light receiving sensors read out via the transfer means And subtraction means for subtracting.

In the image pickup device according to the present invention, the sensitivity of the second light receiving sensor is lower than the sensitivity of the first light receiving sensor.
Further, in the image pickup apparatus according to the present invention, the first light receiving sensor receives the first color and the second light receiving sensor receives the second color.

In the image pickup apparatus according to the present invention, the second color is a bluish color.

[0019]

Since the image reading apparatus, the image reading method, and the image pickup apparatus according to the present invention are configured as described above, the accumulated charge is stored in the pixel before the shading correction for normalizing the image reading signal to the reference white level. It is possible to correct the color mixture by multiplying the image data generated by the light-receiving unit that is transferred by way of the correction coefficient and add the correction to the color that is transferred through the light-receiving unit of another color.

[0020]

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. (First Embodiment) FIG. 1 is a diagram showing a configuration example of a CCD linear image sensor used in a color image reading apparatus of the first embodiment of the present invention, and FIG. 2 is a linear diagram shown in FIG. It is a figure showing an example of 1 composition of a color mixing amendment circuit for amending color mixing in an image sensor.

In FIG. 1, the components indicated by reference numerals 301 to 309 are the same as the components 301 to 309 in FIG. 8 which have already been described in the section "Prior Art". 1 is different from that of FIG. 8 in that light receiving portions 301, 302 and 303 having R (red), G (green) and B (blue) color separation filters are adjacent to each other. . When the light receiving units 301 to 303 read the image, the R light receiving unit 301 applies the accumulated charge for one pixel on the document image to the CC.
To the D transfer units 304 and 305, the B light receiving unit 303 is the CCD
In contrast to the direct transfer to the transfer units 308 and 309, the accumulated charge in the G light receiving unit 302 is once transferred to the B light receiving unit 303 and then to the CCD transfer units 308 and 309 again.

FIG. 3 shows a model of transfer of accumulated charges in the G and B light receiving portions. In FIG. 3, 401 and 402
Represents one pixel of the G and B light receiving portions, respectively. State A in the figure: When image reading is started from the start, the light receiving units 401 and 402 scan the document image in the direction of the arrow in state B. When scanning about one pixel, first, the charge EB accumulated in the B light receiving section 402 is transferred to the B CCD transfer section 404 (state C in the figure).

At this time, assuming that the charge transfer time from the light receiving section to the CCD transfer section is ΔT1, the light receiving section continues scanning during the time ΔT1 and accumulates the charge ΔEB1.
Therefore, the total charge amount sigB at the time when the accumulated charge transfer in the light receiving portion B is completed is represented by sigB = EB + ΔEB1 (1).

Next, as shown in the state D, the accumulated charge EG of the G light receiving portion 401 is transferred to the B light receiving portion 402 in which the electric charge is empty. At this time, if the charge transfer time from the G light receiving portion to the G light receiving portion is ΔT2, then ΔT2 is the same as above.
The accumulated charge .DELTA.EB2 of B in T2 is stored and a color mixture of G and B (EG + .DELTA.EB2) occurs. Further, the charges transferred to the B light receiving section are transferred to the G CCD transfer section 403 (state E). In this case as well, from the light receiving part to the CCD as described above.
During the charge transfer time ΔT1 to the transfer section, the charge of the B light receiving section is Δ
Since EB1 is accumulated, the total charge amount sigG until the charge of the G light receiving portion is finally transferred to the G CCD transfer portion is expressed by sigG = EG + ΔEB2 + ΔEB1 (2), which is mixed with the G signal EG. B signal is ΔEB2 + Δ
It becomes EB1.

Since the R light receiving portion is similar to B according to the configuration example of FIG. 1, it can be expressed by equation (1) as sigR = ER + ΔER1 (3). The charges represented by the equations (1), (2), and (3) sequentially move in the CCD transfer section and are output to the circuit shown in FIG. The operation of this embodiment will be described below with reference to FIG.

The charge output from the CCD transfer section (hereinafter referred to as an analog image signal) is amplified to a certain level by an amplifier circuit (not shown), sample-held by sample-hold circuits 101, 102 and 103, respectively. Is converted into a digital signal by A / D converters 104, 105 and 106. A / D converters 104, 105, 1
The scan row of the line sensor output from the R06 outputs RGB read signals of the nth row by Rn (= sigR) and Gn, respectively.
Assuming that (= sigG) and Bn (= sigB), Bn is multiplied by a color mixture correction coefficient C0, which will be described later, by a multiplier 108, and an adder 109 subtracts C0.Gn from Gn to obtain G'n. That is, G'n = Gn-C0.Bn (4) In the above, Rn, G'n, and Bn are read at the reference white level prior to reading the original image (hereinafter, this read signal is referred to as shading data). The shading data is stored in the shading data memory 113 including the RAMs 110, 111 and 112 for R, G and B, respectively.

In reading the original image, R, G,
Shading correction circuit 1 for each B image signal of RGB
Shading correction is performed by 14, 115 and 116 (generally referred to as a shading correction circuit 117), as in the conventional image reading apparatus. Next, the determination of the color mixture correction coefficient C0 will be described again with reference to FIG.

Now, in FIG. 3, the light receiving portion 402 of B is
Let T be the time required to accumulate the charge EB for one pixel (the light receiving section B obtains the charge EB at the accumulation time T). As described above in the state C of FIG. 3, the time for the light receiving portion to transfer the charge to the CCD transfer portion is ΔT1, so that the light receiving portion for B is ΔT1.
The amount of charge ΔEB1 accumulated in time is ΔEB1 = ΔT1 · EB / T (5). Therefore, from the equation (1), the total charge amount sigB at the time when the accumulated charge transfer of the light receiving portion of B is completed is sigB = EB + ΔT1EB / T = (1 + ΔT1 / T) EB (6) This also applies to the light receiving part of R, and the formula (3)
Therefore, sigR = ER + ΔT1ER / T = (1 + ΔT1 / T) ER (7)

As for the light receiving section G, as shown in the state D of FIG. 3, the time for transferring the charge EG of the G light receiving section to the B light receiving section was ΔT2. The amount of charge ΔEB2 mixed in EG is ΔEB2 = ΔT2 · EB / T (8). Further, the electric charge ΔEB1 accumulated (mixing color) when the electric charge of the B light receiving portion is transferred to the G CCD transfer portion 403 is ΔT1 · EB / T from the equation (5). Then, the total charge amount sigG until the charge of the light receiving portion G is completely transferred to the CCD transfer portion G is obtained from the equation (2): sigG = EG + ΔT2 · EB / T + ΔT1 · EB / T = EG + (ΔT2 + ΔT1) EB / T (9) Becomes After all, the charge amount of the B light receiving portion mixed with the charge EG is (ΔT2 + ΔT1) EB / T, and when this is C times the total charge amount sigB of the B light receiving portion, from equation (6), ΔT2 + ΔT1) EB / T = C · sigB = C · (T + ΔT1) EB / T That is, C = (ΔT2 + ΔT1) / (T + ΔT1) (10), and the accumulated charge amount EG of the light receiving portion of G is the total charge amount sig of G.
It is obtained by subtracting C times the total charge amount sigB of B from G. That is, EG = sigG−C · sigB (11) In FIG. 2, since the B signal Bn is multiplied by C0 by the multiplier 108 and added by the adder 109, when the coefficient C0 is −C, C0 = − ( ΔT2 + ΔT1) / (T + ΔT1) (12)

As described above, with respect to the signal of the G light receiving portion, the shading data and the image reading data are subjected to the weighting of the correction coefficient C0 with respect to the signal of the B light receiving portion, and the shading correction is performed. , Color mixture correction can be realized. Note that the B light receiving portion and the R light receiving portion also have charges ΔEB1 and ΔER1 accumulated during charge transfer. However, since the same color charges are accumulated during shading data reading, shading correction is performed. It is obvious that there is no effect on the subsequent signals, and it can be seen that this correction circuit only needs the G light receiving portion (the color for transferring the charges via the light receiving portions of other colors). (Second Embodiment) In the first embodiment, the amount of charge (ΔEB2 + ΔEB1) of the B light receiving portion mixed with the electric charge EG accumulated in the G light receiving portion is calculated by the equation (9). Although it was determined by the accumulation time ratio (ΔT2 + ΔT1) / T of the accumulated electric charge EB in the part, in reality, the electric charge is transferred within a finite time ΔT between the pixels and the sampling interval of the pixel. The amount of mixed charge that is accumulated at the moment interposes charge transfer,
It is determined from the charge amount of both pixels.

Hereinafter, this point will be described with reference to FIGS. 4 and 5. FIG. 4 shows a temporal change of the incident light amount when the light receiving portion of B reads the original image. The horizontal axis represents time and the vertical axis represents the incident light amount. In the figure, for example, the amount of incident light changes according to the reflectance of the original image, as shown by the curve, and the amount of accumulated charge is proportional to the product of the amount of incident light and the accumulation time (hatched area in the figure).

Now, the sampling interval of the image is "← 1" in the figure.
In the section indicated by “pixel →”, charge transfer is performed in a finite time centered on sampling switching. In particular, the charge of the B light receiving portion mixed with the G light receiving portion is transferred time (ΔT2) from the G light receiving portion to the B light receiving portion as shown in FIG.
Transfer time from the B and B light receiving parts to the G CCD transfer part (ΔT
1) accumulated by.

At this time, the accumulated charge amount is ΔE in the shaded area in FIG.
It is expressed by B. This charge amount is first accumulated by ΔT2 and then by ΔT1, so the accumulated charge amount at this time is EBn for ΔT2 time and by the charge EBn + 1 of the next pixel for ΔT1 time. Can be approximated. That is, the equation (9) can be rewritten as follows.

SigG = EG + ΔT2EBn / T + ΔT1EBn + 1 / T (13) The mixed charge amount (the second term and the third term on the right side of the expression (13)) are sigBn and sigBn + 1 of the expression (6). By doing this, ΔT2 ・ EBn / T + ΔT1 ・ EBn + 1 / T = ΔT2 ・ T ・ sigBn / T ・ (T + ΔT1) + ΔT1 ・ T ・ sigBn + 1 / T ・ (T + ΔT1) = ΔT2 ・ sigBn / (T + ΔT1) + ΔT1 ・ sigBn + 1 / (T + ΔT1) (14) This is because the correction coefficient C1 C1 =-. DELTA.T2 / (T + .DELTA.T1) (15) is multiplied by the total charge amount sigBn of the light receiving portion of B, and the correction coefficient C2 C2 =-. DELTA.T1 / (T + .DELTA.T1) (16) is calculated as follows. It is nothing more than the total charge amount sigBn + 1 of the pixel of FIG.

A circuit configuration for realizing this is shown in FIG.
In FIG. 5, the line memories 501, 502, and 503 are B
This is a line memory for synchronizing when the correction term of the image signal delayed by one line of the light receiving portion of G and the target line is subtracted from the image signal of the light receiving portion of G. Of these, R of 501 is not shown. If it is performed in a later process, it is not necessary here.

Image signal Bn delayed by one line at 503
Then, the next line Bn + 1 is multiplied by the correction coefficients C1 and C2 represented by the equations (15) and (16) by the multipliers 505 and 506 and added by the adder 506. This correction term (represented by formula (14)) is realized by adding G1n to the image signal Gn delayed by one line to obtain G'n. (Third Embodiment) In the first and second embodiments,
The R, G and B light receiving parts were adjacent as shown in FIG.
Even if the respective light receiving parts are spaced as shown in FIG. 8, the required amount of line memories 501, 502, 503 in FIG. It is possible to correct the color mixture by the same correction method. .

As described above, according to the above-described embodiment, for the image data transferred to the CCD transfer section via the accumulated charge to the light receiving section of another color, the received light of the color through which the accumulated charge passes. By multiplying and subtracting the correction coefficient from the image data by the unit, it is possible to correct the color mixture that occurs when the accumulated charge is transferred in the pixel of another color.

[0038]

As described above, according to the image reading apparatus, the image reading method, and the image pickup apparatus according to the present invention, the accumulated charge is stored in the pixel before the shading correction for normalizing the image reading signal to the reference white level. The color mixture can be corrected by multiplying the image data generated by the light receiving unit transferred via the correction coefficient by the correction coefficient and by adding the correction to the color transferred through the light receiving unit of another color.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a linear image sensor used in an image reading apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of an image reading apparatus according to a first embodiment of the present invention.

FIG. 3 is a diagram showing the movement of charges in the pixel transfer of the present invention.

FIG. 4 is a diagram for explaining image reading according to the second embodiment of the present invention.

FIG. 5 is a diagram showing a configuration of an image reading apparatus according to a second embodiment of the present invention.

FIG. 6 is a diagram illustrating an optical system of a conventional color image reading device.

FIG. 7: Light-receiving part of conventional color image reading device, CC
It is a figure which shows the structure of a D transfer part.

FIG. 8: Light-receiving part of conventional color image reading device, CC
It is a figure which shows the structure of a D transfer part.

[Explanation of symbols]

101 sample hold R 102 sample hold G 103 sample hold B 104 A / D conversion circuit R 105 A / D conversion circuit G 106 A / D conversion circuit B 108 multiplier 109 adder 110 shading RAM-R 111 shading RAM-G 112 Shading RAM-B 113 Shading memory set 114 Shading correction circuit R 115 Shading correction circuit G 116 Shading correction circuit B 117 Shading correction circuit set 201 CCD 202 Lens 203 Broken line portion 205 Second mirror 206 Third mirror 207 Broken line portion 208 First mirror 209 Reflective shade 210 Light source 211 Manuscript table glass 212 Original 301 Light receiving part R 302 Light receiving part G 303 Light receiving part B 304, 305, 306, 307 308,309 C
CD transfer section 310, 311, 312, 313, 314, 315 amplifier 401 light receiving section G 402 light receiving section B 403 CCD transfer section G 404 CCD transfer section B 501, 502, 503 line memory 504, 505 multiplier 506 adder

Claims (16)

[Claims] 1. An image reading apparatus for reading a color image by scanning a document in a main scanning direction and a sub-scanning direction while irradiating the document and photoelectrically converting reflected light reflected from the document using an image line sensor. A plurality of image line sensors each provided with a color filter of a plurality of colors, and a transfer unit arranged on both sides in the width direction of the plurality of image line sensors for transferring charges from the image line sensors. A linear image sensor that is configured to pass through the image line sensor of another color when the electric charge received and accumulated by the image line sensor of at least one color is sent to the transfer unit. Compensate the electric charge that has passed through the image line sensor of the other color to the electric charge received and accumulated by the image line sensor of the other color Image reading apparatus characterized by comprising a subtraction means for subtracting the multiplied by a number. 2. The image reading apparatus according to claim 1, wherein the multiplication of the correction coefficient and the subtraction of the charge multiplied by the correction coefficient are performed prior to normalization with respect to the reference white. 3. The correction coefficient is uniquely defined from a time required to pass an electric charge, a time required to transfer the electric charge from the image line sensor of a color through which the electric charge is passed to the transfer unit, and an accumulation time of the electric charge. The image reading device according to claim 1, wherein the image reading device is a constant that is determined. 4. A memory for at least one line is provided,
The charge of the image line sensor through which the charge is transferred is
2. The image reading according to claim 1, wherein the correction coefficient is the charge of two pixels before and after the charge transfer, and the correction coefficient is at least two kinds of constants determined for each of the charges of the two pixels. apparatus. 5. The time required to pass the charge is ΔT2, the time required to transfer the charge from the image line sensor to the transfer unit is ΔT1, and the charge storage time is T.
Then, the correction coefficient is − (ΔT2 + ΔT1) / (T
The image reading device according to claim 3, wherein the image reading device is represented by + ΔT1). 6. The correction coefficients for the charges of the two pixels before and after the charge transfer are −ΔT2 / (T + ΔT1) and −ΔT1 respectively.
The image reading apparatus according to claim 4, wherein the image reading apparatus is represented by / (T + ΔT1). 7. An image reading method for reading a color image by scanning a document in the main scanning direction and the sub-scanning direction while irradiating the document with light, and photoelectrically converting reflected light reflected from the document using an image line sensor. A plurality of image line sensors each provided with a color filter of a plurality of colors, and a transfer unit arranged on both sides in the width direction of the plurality of image line sensors for transferring charges from the image line sensors. A linear image sensor configured to pass through the image line sensor of another color when the electric charge received and accumulated by the image line sensor of at least one color is sent to the transfer unit. The charge that has passed through the color image line sensor is converted into the charge received and accumulated by the other color image line sensor. Image reading method characterized by subtracting a multiplied by a positive coefficient. 8. The image reading method according to claim 7, wherein the multiplication of the correction coefficient and the subtraction of the charge multiplied by the correction coefficient are performed prior to normalization with respect to the reference white. 9. The correction coefficient is uniquely defined from a time required for passing charges, a time required for transferring charges from an image line sensor of a color through which charges are transferred to the transfer unit, and a charge accumulation time. The image reading method according to claim 7, wherein the image reading method is a constant that is determined. 10. A charge of an image line sensor including a memory for at least one line, the charge of two pixels before and after a charge transfer, and the correction coefficient of the two pixels. The image reading method according to claim 7, wherein there are at least two kinds of constants determined for each of the electric charges. 11. The correction coefficient is −T, where ΔT2 is the time required to pass the charges, ΔT1 is the time required to transfer the charges from the image line sensor to be passed to the transfer section, and T is the charge storage time. (ΔT2 + ΔT1) /
10. It is represented by (T + ΔT1).
The image reading method described in. 12. The correction coefficients for the charges of two pixels before and after the charge transfer are −ΔT2 / (T + ΔT1) and −ΔT, respectively.
11. The image reading method according to claim 10, which is represented by 1 / (T + ΔT1). 13. A first light receiving sensor, a second light receiving sensor, a first light receiving sensor, a second light receiving sensor, a first light receiving sensor, a second light receiving sensor, and a second light receiving sensor.
Transfer means for reading the electric charge of the light receiving sensor, the charge signal of the second light receiving sensor is read out through the transfer means, and the charge signal of the first light receiving sensor is passed through the second light receiving sensor. And a transfer means for transferring to the transfer means and then reading through the transfer means, and a subtracting means for subtracting the signals of the first and second light receiving sensors read out through the transfer means. An image pickup apparatus comprising: 14. The imaging device according to claim 13, wherein the sensitivity of the second light receiving sensor is lower than the sensitivity of the first light receiving sensor. 15. The image pickup apparatus according to claim 13, wherein the first light receiving sensor receives a first color and the second light receiving sensor receives a second color. . 16. The image pickup apparatus according to claim 15, wherein the second color is a bluish color.