JPS6351437B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a solid-state color imaging device comprising a color filter and a single solid-state imaging device that forms an image through the color filter. This is an example of a field storage type solid-state image sensor that is not applicable to a single-chip color image sensor. The present invention provides a solid-state color imaging device which is also applicable to frame transfer type solid-state imaging devices and has improved sensitivity and resolution.

A solid-state image sensor consists of a two-dimensionally arranged photosensitive element and a scanning circuit that sequentially scans the photosensitive element, and converts a subject image formed on the surface of the two-dimensionally arranged photosensitive element into an electrical signal. It is.

These solid-state image sensing devices are generally classified into interline type, frame transfer type, XY address type, etc. depending on the scanning method.
The single-chip color camera sequentially arranges color filters that transmit different colored lights on the photosensitive element on the solid-state image sensor,
This device forms a subject image on a solid-state image sensor through the color filter, obtains a spatially modulated color signal and a luminance signal from the solid-state image sensor, and synthesizes a composite color signal from these signals.

On the other hand, a solid-state image sensor is a type of large-scale integrated circuit, and it is desirable to keep the degree of integration low in order to improve manufacturing yield. As a result, it is desirable that the number of photosensitive elements arranged two-dimensionally (the number of pixels) is the minimum number of pixels determined by the number of pixels to obtain the required resolution.The colorization method reduces this resolution. It is requested that the system be used in a way that will not cause any problems.
Furthermore, since current solid-state image sensors are not necessarily superior in sensitivity to conventional image pickup tubes, the light utilization efficiency of the optical system must be maximized.

As for the single-chip coloring method, many methods have been proposed depending on the type and characteristics of the solid-state image sensor, mainly for the purpose of improving the functions of the above two points (namely, resolution and sensitivity).

FIG. 1 shows a conventional method using color filters in which filters that transmit the three most basic primary colors are sequentially repeated in the horizontal direction (hereinafter referred to as the first method). Here, reference numeral 101 indicates a photosensitive portion on the solid-state image sensor, and reference numerals 102, 103, and 104 indicate filters that transmit three different primary color lights. When using such a filter, the horizontal color repetition has a cycle of 3 pixels, so the carrier of the spatially modulated color signal is 1/3 of the sampling frequency determined by the number of pixels.
becomes the frequency of Therefore, the band of the luminance signal (1/2 of the sampling frequency for low chroma objects)
Since color carriers are included in the image, the luminance band must be limited to 1/3 of the sampling frequency, resulting in a decrease in horizontal resolution.

In this sense, the method shown in Figure 2 (hereinafter referred to as the 2nd method) improves the horizontal resolution.
126592).

In FIG. 2, nH indicates the n-th horizontal scan in the first field, and nH' indicates the n-th horizontal scan in the second field.
This method is configured to sequentially obtain a first color difference signal in the n-th horizontal scan, and to sequentially obtain a second color-difference signal in the (n+1)th horizontal scan. Therefore, in order to equalize the average value of brightness in each horizontal scan, each pixel is divided and a filter that transmits two different colored lights is arranged.

For example, the pixel 201 includes a filter R202 that transmits red light and a filter ΔCy2 that blocks red light.
03 is placed. Since the horizontal filter is repeated twice, the carrier of the spatially modulated color signal is 1/2 of the sampling frequency determined by the pixel.
This is outside the brightness band.

However, this method has the following two drawbacks; the first is the complexity of the pixels. As mentioned earlier, solid-state image sensors are extremely high-density integrated circuits.
As circuits become more integrated, color filters also become smaller.
Here, this method of dividing pixels and arranging filters requires further miniaturization than the pixel-filter method, making it difficult to manufacture the filters. Second, a frame transfer type solid-state image sensor (TV Society Technical Report "512 x 466 CCD Image Sensor" by Horii et al., 1984) has a vertical sensitivity spread because it uses the vertical correlation of objects for color separation.
(September, ED-394) has drawbacks that make it inapplicable.

The third method is another method that does not reduce the horizontal resolution.
There is a method using the filter shown in the figure (hereinafter referred to as 3).
It is called a method. (See TV Society Journal, Single Image Plate Color Television Camera, Vol. 33, No. 7 (1979), 554 (40)).

This method scans the n-th horizontal column and the (n+1)-th horizontal column simultaneously, and the n-th horizontal scan (nH)
By applying this method to a solid-state imaging device, the sum of G signals from two horizontal columns is used as a luminance signal, and two color difference signals are obtained from each column.

As a result, the G color is actually repeated once in each horizontal scan, and the luminance band can be used up to the band determined by the number of pixels in the horizontal direction.

However, this method can only be applied to an XY address type image sensor that can simultaneously scan two horizontal columns and output two independent output signals.

Furthermore, since all methods 1 to 3 described above use primary color filters, the luminance band for highly saturated subject images is also narrow. Also, using primary color filters reduces the transmittance of the color filters, which reduces the sensitivity of the solid state color imaging device.

As mentioned above, each of the currently known methods 1 to 3
All of these are unsatisfactory from the point of view of overall characteristics, and it is desired to improve these drawbacks.

The present invention provides a solid-state color imaging device that eliminates the above-mentioned conventional drawbacks and improves overall characteristics such as sensitivity and resolution.

First, the basic configuration of the present invention will be explained based on FIG. 4 showing one embodiment thereof.

The part indicated by the broken line in FIG. 4 indicates the photosensitive part of the solid-state image sensor. That is, in this configuration, a color filter (W filter) 409 that transmits all color light is arranged at the i-th pixel 401 in the n-th horizontal row of the solid-state image sensor, and a green light is arranged at the i-th pixel 402 in the same row. A transmitting filter (G filter) 410 is arranged. Furthermore, a filter (Ye filter) 411 that blocks blue light is arranged in the i-th pixel 403 of the n+1-th horizontal column, and
A filter (Cy filter) 412 that blocks red light is placed in the +1st pixel 404. Furthermore, a G filter 410 is placed in the i-th pixel 405 of the n+2nd horizontal column, and the i+1th pixel 4
A W filter 409 is placed at 06, and a Ye filter 41 is placed at the i-th pixel 407 of the n+3-th horizontal column.
1, and Cy filter 4 is placed on the i+1st pixel.
12 are arranged, and the above filters are sequentially repeated in the vertical and horizontal directions.

The following scanning is performed in the solid-state image sensor equipped with the color filter. In the first field, charges in two adjacent horizontal columns are added, such as the nth and n+1st horizontal columns, the n+2nd and n+3rd, the n+4th and n+5th, and so on, and the added charges are transferred. In the second field, the horizontal columns n+1, n+2, and n+
3rd and n+4th, n+5th and n+6th...
..., the charges in two adjacent columns are added by shifting one column, and the added charges are transferred.

The output of the solid-state imaging device equipped with the filter is equivalent to the output of the solid-state imaging device equipped with the color filter shown in FIGS. 5a and 5b.

This will be explained with reference to FIG. 5a.

In FIG. 4, the m-th horizontal scan is n and n+
Scan one horizontal row at a time. For this reason, Figure 5a
The output from the i-th pixel of the m-th horizontal scan is the sum of the signals of the pixel 409 and the pixel 411. Since the pixel 409 is provided with a W filter, the spectral characteristics of the output signal of this pixel are proportional to the W filter, assuming that the spectral characteristics of the solid-state image sensor are flat.

Similarly, the pixel 403 with the Ye filter is
It has spectral characteristics proportional to the filter. As mentioned earlier, in the m-th horizontal scan, pixel 401 and pixel 40
Since the sum of the signals with 3 and 3 is output,
As shown in FIG. 5a, effectively m-th horizontal scanning,
The i-th pixel output is the sum of the spectral characteristics of the previous W filter and Ye filter. In this sense, FIGS. 5a and 5b are rewritten versions of FIG. 4.

FIG. 5a means the horizontal scanning of the first field, and FIG. 5b means the horizontal scanning of the second field. That is, in FIG. 5a, the i-th pixel in the m-th horizontal scan has the W+Ye spectral characteristic, the i-th pixel has the G+Cy spectral characteristic, and the i-th pixel in the m+1-th horizontal scan has the W+Ye spectral characteristic, as described above. The pixel has a G+Ye spectral characteristic, and the i+1th pixel is equivalent to pixels having a W+Cy spectral characteristic repeated vertically and horizontally. FIG. 5b shows an example of the second field, in which the interlacing operation is performed by changing the pair of combinations in which the signals of two pixels in the vertical direction are added.

In this way, the signals of vertically adjacent pixels are added and then transferred.

Therefore, as in Japanese Patent Laid-Open No. 51-56123, in which two line signals in the horizontal scanning direction are read out simultaneously and the combination is changed for each field, all pixels are read out during one field, resulting in frame afterimages. There is no. Furthermore, the unique configuration of the present invention is that the signals of vertically adjacent pixels are added and then transferred, so the transfer section is simpler and the output stage is simpler than that of JP-A-51-56123. Since there is only one output stage, the influence of noise generated at the output stage is reduced.

Moreover, a color filter, which is a filter of one color, is easy to manufacture for one pixel of a solid-state image sensor, and it is also easy to bond a color filter to a solid-state image sensor.

In this way, two types of color filters such as W and G that transmit different colored lights are installed in the first horizontal row so that color separation can be achieved even if the combination of vertical pixels adjacent to each other is changed for each field. One color is repeatedly arranged horizontally in each pixel of the solid-state image sensor, and in the next horizontal row (second horizontal row) two types of color filters, such as Ye and Cy, are placed in different combinations from the first row. One color is repeatedly arranged in the horizontal direction for each pixel of the solid-state image sensor.

In the next horizontal row (third horizontal row), the two types of color filters used in the first horizontal row, such as G and W, are
One color is arranged in each pixel of the solid-state image sensor so that the spatial phase differs by 180 degrees from the horizontal row, and the next horizontal row (fourth horizontal row) is arranged in the same way as the second horizontal row. .
An example of reading out such a color filter with different combinations for each field is shown below.

The spectral characteristics of the equivalent pixel in FIG. 5 are the characteristics shown in FIGS. 6a and 6b.

That is, the characteristics of the i-th equivalent pixel in the m-th horizontal scan in FIG. 5a are shown by the solid line (W+Ye) in FIG. 6a, and the characteristics of the i+1-th equivalent pixel in FIG. The response of the video signal by the m-th horizontal scan in which equivalent pixels having such two types of spectral characteristics are sequentially arranged in the horizontal direction has the characteristics shown in FIG. That is, the shaded area in FIG. 7a appears as a spatially modulated color signal.
Since this is a repetition of two horizontal pixels, it is 1/2 of the sampling frequency (s) determined by the number of horizontal pixels.
appears at the point. Moreover, this spatially modulated color signal is the primary color signal red, as seen from the shaded area in FIG. 6a. On the other hand, since the number of samples in the horizontal direction for a low-saturation subject is equal to the number of pixels, the luminance band extends to 1/2 of the number of samples as shown in FIG. Similarly, i of the m+1th horizontal scan
The i+1th equivalent pixel G+Ye is indicated by the broken line in FIG. 6b, and the i+1st equivalent pixel W+Gy is shown in FIG. 6b.
It has the characteristics shown by the solid line. What is spatially modulated as a result is the shaded area in FIG. 6b, that is, the primary color signal blue. Also, the average value of horizontal spectral characteristics (luminance spectral characteristics) in the m-th horizontal scan is W, Ye,
It is proportional to the addition of G and Cy spectral characteristics, and the same holds true for the m+1st horizontal scan. As a result, the average values of the two horizontal scans match, and no line crawl (shading of brightness for each scanning line) occurs. Also, the proportion of primary color light included in the luminance signal is W=R+G+B Ye=R+G G=G Cy=B+G, so W+Ye+G+Cy=2R+4G+2B This has a convenient approximation value to apply to the ratio of NTSC luminance R:G:B=0.3:0.59:0.11.

The above can be summarized as follows.

A solid-state color imaging device, in which a color filter shown in Fig. 4 is arranged on a solid-state imaging device that simultaneously adds and outputs two horizontal columns in one horizontal scan, horizontally scans a video signal containing spatially modulated primary color signals R and B. Output each time sequentially.

The element signals output in this manner are converted into NTSC signals through a signal processing circuit as shown in FIG.
The solid-state image sensor 801 in FIG. 8 is as described above, and the element output signal (hereinafter referred to as element output signal a) output from this solid-state image sensor passing through point a is a spatially modulated primary color signal. This is a video signal containing The element output signal a is first sent to the detection circuit 802.
sent to. 802 is a detection circuit that performs the following operations. The first horizontally scanned element output signal is W+
Ye, G+Cy, W+Ye, G+Cy... and taking the difference between these adjacent output signals, we get R, -R, R,
Obtain the signal -R. This is synchronously detected to obtain an R signal.

The second horizontally scanned element output signal is G+Ye,
W+Cy, G+Ye, W+Cy... and taking the difference between these adjacent output signals -B, B, -B, B
I get this signal. This is synchronously detected to obtain the B signal. In this way, the color signals R and B are sequentially sent to the subtracter for each horizontal scan. On the other hand, the element output signal is sent to a gain switch 807 as a luminance signal (Y _L ) having the same band as the chrominance signal via a low-pass filter 806 limited to the chrominance signal band. The gain switch 807 is a circuit that switches the gain of the luminance signal (Y _L ) in synchronization with the horizontal scan at a frequency of 1/2 of the horizontal scan.
The luminance signal (Y _L ) whose gain has been changed for each horizontal scan is sent to the subtracter 803 via this circuit.
It is subtracted from the detected color signal. As a result, the subtracter 803 outputs color difference signals R-Y _L and B-Y _L sequentially for each horizontal scan. The aforementioned gain switch 807 is provided to independently adjust the white balance of the color difference signals corresponding to the primary color signal R or B. The synchronization circuit 804 is composed of a one-horizontal scan delay device 805 and a one-horizontal scan switch 806', and synchronizes the sequentially sent color difference signals for each horizontal scan and sends them to the encoder 810.

On the other hand, the element output signal a is converted into a luminance signal via a second low frequency converter 809 having a pole at 1/2 of the horizontal sampling frequency, and is sent to an encoder 810. The encoder 810 can output an NTSC signal based on the two color difference signals R-Y _L and B-Y _L from the synchronization circuit 804 and the luminance signal from the low frequency converter 809 . Since this method obtains a luminance signal by adding adjacent pixels in the vertical direction, there is no change in signal level for each horizontal scanning line of the luminance signal obtained when a uniform subject is imaged. This increases the degree of freedom in determining the arrangement of color filters in a single-chip color camera.

In other words, the important factors that determine the color filter arrangement of a single-chip color camera are: (1) ability to separate colors; (2) no difference in luminance signal level between horizontal scans when imaging a uniform subject; It is.

In the present invention, no matter what combination of colors is used, when a uniform object is imaged, no difference occurs in the level of the luminance signal for each horizontal scan.

For example, an example using four different colors A, B, C, and D will be explained.

In the first row, A, B, A, B... In the second row, C, D, C, D... In the third row, B, A, B, A... In the fourth row, C, D, C, D... In the 5th column, A, B, A, B... (Return to the same array as the first column) becomes a color array.

In the first field, the signals modulated by the color filters in the first and second columns are added and read out, so the first horizontal scanning signal is A+C, B+D, A+C, B+D, . . . .
Since the signals modulated by the color filters in the third and fourth columns are added and read out, the second horizontal scanning signal is C+B, D+A, C+B, D+A, . . . .

In the second field, the signals modulated by the second column and the third color filter are added and read out, so the first horizontal scanning signal is C+B, D+A, C+B, D+A,...Similarly, the second horizontal scanning signal is The horizontal scanning signals are C+A, D+A, C+A, D+B...

A luminance signal Y ₀ Y ₀ =A+B+C+D is obtained through these signals LPF (low pass filter).

In this way, even if the average value of the color filters A and B in the first and third columns is different from the average value of the color filters C and D in the second and fourth columns, the luminance signal is A+B+C+
D, so there is no difference between horizontal scans.

Next, color separation will be explained.

It is obtained by synchronously detecting the difference signal between adjacent horizontal scanning signals. The difference signal between adjacent signals of the first horizontal scanning signal of the first field is (A+C)-(B+D)= _C1 , (B+D)-(A+C)=- _C1 , _C1 , _-C1 , ... The difference signal between adjacent signals of the second horizontal scanning signal is (C+B) - (D + A) = C ₂ , (C + B) - (D + A) = -C ₂ , C ₂ , -C ₂ , ... obtain. This is synchronously detected to obtain C ₁ and C ₂ . _C1 ,
Since _C2 is a sequential signal for each horizontal scan, it is synchronized. Synchronized C ₁ and C ₂ chrominance and luminance signals
Perform matrixing with _Y0 to obtain the color difference signal of the standard television signal. The same applies to the second field. By changing the matrix each time the color combination of A, B, C, and D changes, a color difference signal of a standard television signal can be obtained.

When a uniform object is imaged in this way, no difference in the level of the luminance signal occurs, so the degree of freedom in the colorization method increases.

The above was explained using the color filter arrangement of W, G, Ye, Cy as an example, but for example, Mg, G, Ye, Cy
It goes without saying that the same objective can be achieved with the color filter arrangement or other similar four types of color filter arrangement.

Next, an example in which the present invention is applied to a frame transfer CCD solid-state image sensor will be shown. frame trump
The pixels of a CCD solid-state image sensor have sensitivity spread in the vertical direction. On the other hand, the second and third methods for colorization described above perform color separation based on the vertical correlation of subject images. For this purpose, the second
To apply the third method, pixels in the vertical direction must be completely separated. From the above, conventional frame transfer CCD solid-state image sensors are
It has been thought that only the first method mentioned above can be applied.

However, as mentioned above, the horizontal resolution of the first method is lower than that of the second and third methods.

Since the present invention is characterized by adding the signals of two pixels in the vertical direction, expanding the pixel sensitivity in the vertical direction is equivalent to optically adding the signals of two pixels in the vertical direction. .

FIG. 9a shows the structure of an embodiment suitable for a frame transfer CCD. The image sensor moves a video signal photoelectrically converted in an image unit 903 to a storage unit 902 field by field, and transfers it to a horizontal analog shift register 901 in synchronization with horizontal scanning, and then passes it through the register as a video signal. This is what is output. FIG. 9b is an enlarged view of section A in FIG. 9a, showing the relationship between the color filters and the elements. FIG. 9c shows the XX' section of FIG. 9b and the pixel sensitivity distribution in each field.
From FIGS. 9b and 9c, the sensitivity distribution (solid line 914) in the first field is centered around the first vertical transfer electrode 909 and the second electrode 910, and the filter on this pixel is the W filter 905 and the Ye filter. 906, G filter 907 and Cy filter 908, G filter and Ye filter, or W and Cy filter. Since these arrangements are similar to those shown in FIG. It is possible to create a single-chip color camera that can obtain horizontal resolution equivalent to that of the three colorization methods.

That is, in the frame transfer CCD, the filter 9 in FIG. 9b is used in the first field.
After adding the signals obtained from 05 and 906 (filters 907 and 908), vertical transfer is performed, and in the second field, the signals obtained from filter 90 of FIG.
The interlacing operation is performed by adding the signals obtained from 6 and 905' (filters 908 and 907') and then performing vertical transfer.

Next, a case where the present invention is applied to an interline CCD type solid-state image sensor will be explained using FIG. 10.

FIG. 10 shows an example in which the present invention is applied to an interline CCD solid-state image sensor.

The interline CCD solid-state image sensor reads out signals photoelectrically converted by the photosensitive section 1001 and sends them to the readout gate 1.
By sequentially applying two read signals 1003 and 1004 to 002 in synchronization with vertical scanning, the read gate is opened, and the vertical analog shift register 1005
and sequentially send it to the horizontal analog shift register 1006 in synchronization with horizontal scanning, and at the same time, in synchronization with horizontal scanning, the signal in the horizontal analog shift register is sent to the output, thereby outputting a video signal. For such an element, a W filter 1007 is placed on the first pixel of the first horizontal column, a G filter 1008 is placed on the second pixel, a Ye filter 1009 is placed on the first pixel of the second horizontal column, Cy filter 10 on the second pixel
10, G filter 1 on the first pixel on the third horizontal row
012, W filter 1013 on the second pixel, fourth
A Ye filter 1014 is applied to the first pixel of the horizontal column of
A Cy filter 1015 is arranged at the second pixel.

When the filter of the present invention is applied to an interline CCD solid-state image sensor, reading is performed as follows.

That is, in the first field, a read signal is first applied to the read signal line 1004 to open the read gate 1002, and a Ye signal is input to the first transfer stage 1017 of the vertical transfer stages 1005. Next, perform one stage transfer in the vertical direction. That is, the signal in 1017 is transferred to 1016. Next, the readout line 100
A read signal is applied to 3, the read gate 1002 is opened, and a W signal is input to the vertical transfer stage 1005. As a result, the Ye signal and W signal in the vertical transfer stage 1005 are mixed to become a Ye+W signal. Similarly, the first
In the field, Cy+G signal, Ye+G
The signals Cy+W and Cy+W are mixed in the vertical transfer stage. At this time, the arrangement of color signals in the vertical transfer stage is similar to that shown in FIG. This makes it possible to perform an interlaced operation and to obtain an equivalent pixel arrangement as shown in FIG. 5 in the same way as in the first field.

In other words, in an interline CCD, the first
Filters 1007 and 1 in FIG.
009 (filters 1008 and 1010) are added and then transferred, and in the second field, the signals obtained by filters 1009 and 1 in FIG.
012 (filters 1010 and 1013) are added and then transferred to perform interlace operation. From this, the present invention can also be applied to an interline type CCD solid-state image sensor as described above.

Finally, there is the case of a MOS type solid-state image sensor as an XY addressing method, for example,
By applying a vertical interlacing circuit such as that disclosed in Japanese Patent Application Laid-open No. 155010 or Japanese Patent Application Laid-open No. 137774/1983 to a conventional element, it becomes possible to read out two adjacent horizontal columns, making it possible to use the filter of the present invention. Become.

The following can be considered in the same way as in the case of an interline CCD image sensor.

As described above, since signals obtained from adjacent pixels in the vertical direction are added and then transferred, only one horizontal transfer section is required, the configuration is simple, and the S/N ratio is good. Furthermore, since all pixel signals are read out in one field, there is no frame afterimage. Since the signals of two pixels are added, the vertical resolution is the best and there is no interlace flicker. Furthermore, the filters used in the first horizontal column and the third horizontal column are the same, but have different spatial phases, and the filters used in the second and fourth horizontal columns are the same, and the filters used in the adjacent vertical columns are the same. Since signals from pixels in different directions are added, no matter what combination of filters is used, when a uniform object is imaged,
No difference in level of luminance signals occurs. Therefore, the degree of freedom in the colorization method is large, and the horizontal resolution does not deteriorate. In other words, nearly 100% of the horizontal resolution of the solid-state image sensor used can be used. Furthermore, it has many excellent features such as being able to obtain high horizontal resolution regardless of the type of solid-state image sensor used.

[Brief explanation of drawings]

Figures 1 to 3 are block diagrams of color filters used in conventional solid-state color imaging devices, respectively.
5 is a configuration diagram of a color filter of a solid-state color imaging device according to an embodiment of the present invention; FIGS. 5a and 5b are diagrams showing an equivalent arrangement of the color filter in FIG. Figure 6 a and b are the fourth
7 is a diagram showing the response of the video signal of the solid-state color imaging device shown in FIG. 4, and FIG. 8 is a diagram showing the signal processing of the solid-state color imaging device in one embodiment of the present invention. Circuit block diagram, Figures 9a-c are frame transfer CCD
FIG. 10 is a diagram showing an embodiment in which the present invention is applied to a solid-state imaging device. FIG. 10 is a diagram showing an embodiment in which the invention is applied to an interline CCD solid-state imaging device. 401 to 408... Pixel, 409... Transparent filter, 410... Green light transmitting filter, 411... Yellow light transmitting filter, 412... Cyan light transmitting filter.

Claims (1)

[Claims] 1. A first horizontal row of color filters in which at least two types of color filters that transmit different colored light are arranged repeatedly; and a second horizontal row of color filters in which two kinds of color filters in a different combination than the first horizontal row of color filters are arranged repeatedly. A combination of a row color filter and a color filter that is the same as the first horizontal row color filter, a third horizontal row color filter whose phase is spatially different by 180°, and a fourth horizontal row color filter that is the same as the second horizontal row color filter. A group of color filters in which horizontal row color filters of The charges obtained from the filter and the second horizontal color filter are summed, while the charges obtained from the third horizontal color filter and the fourth horizontal color filter are summed, and in the next field the charges obtained from the second horizontal color filter are added. adding the charges obtained from the horizontal row color filter and the third horizontal row color filter, while adding the charges from the fourth horizontal row color filter and the fifth horizontal row color filter;
a device for transferring the added charges; a circuit for applying a low-pass filter to the signal obtained from the solid-state image sensor to obtain a luminance signal; and a circuit for obtaining a color signal that differs for each horizontal scan from the difference between adjacent signals. A solid-state color imaging device comprising: a circuit that sequentially synchronizes color signals for each horizontal scan.