JPH0313192A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To prevent the deterioration in an S/N and a false signal occurring by arranging first color filters in checkered shape, and arranging second, third, and fourth color filters among the first color filters in stripe shape. CONSTITUTION:W filters are arranged in checkered shape, and the color filters of R, G, and B are arranged among the W filters in stripe shape, and a luminance signal is formed by adding the W signals on two horizontal lines, and the R, G, and B signals on the two horizontal lines are used as chrominance signals. Thereby, it is not required to form the chrominance signal G by computing, therefore, neither deterioration in the S/N nor the false signal occurs, and the luminance signal with a wide band area and three primary chrominance signals with high color reproducibility and high S/N can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a solid-state imaging device, and particularly to a solid-state imaging device in which a plurality of charge conversion elements are provided with a plurality of color filters.

[Prior Art] FIG. 6 is a configuration diagram of a color filter used in a conventional solid-state imaging device.

As shown in the figure, the color filter used in the conventional solid-state imaging device consists of a gold-transmitting W filter arranged in a checkerboard pattern, a red-transmitting R filter and a blue-transmitting B filter arranged in line order. has been done.

Luminance signal Y in a sensor with such a color filter arrangement
and color signal G are formed as follows.

The luminance signal Y is formed by adding the W signals of two horizontal lines, and the chrominance signal G is formed by calculating .Rk2.B on W-. Here kk2 is a sensor, a color filter,
This value is determined based on the desired color temperature of the light source, etc.

For example, the luminance signal Y1 of the horizontal scanning line corresponding to odd 1 of the odd field is Y1=W + + W2,
The color signal G1 is G l == (wt + W!) /
2-'-k l'R- is formed by the operation of 2·B2.

In an even field, a luminance signal Y and a color signal G are formed by changing the combinations of three water lines (even 1, even 2, . . . in the figure).

[Problems to be Solved by the Invention] Such color filter systems have the following problems.

First, since the spatial arrangement of each color filter is different, the vertical correlation of the signals decreases, resulting in the generation of false signals. Further, if noise increases due to the subtraction process and the color temperature at the time of imaging differs, it is necessary to change the subtraction coefficient. This problem is caused by the fact that the color signal G is formed by calculating each color signal.

[Means for Solving the Problems] A photoelectric conversion device of the present invention is a solid-state imaging device in which a plurality of color filters are provided in a plurality of photoelectric conversion elements. 3rd, 4th
The color filters are arranged in stripes between the first color filters.

[Function] The solid-state imaging device of the present invention has a first color filter arranged in a checkerboard pattern, and second, third, and fourth color filters arranged in a stripe pattern between the first color filters. , first,
The first to fourth color signals are obtained from the photoelectric conversion elements of the tri-water line provided with the second, third, and fourth color filters, and the luminance signal is also obtained.

[Example] Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a configuration diagram of a color filter used in the solid-state imaging device of the present invention.

As shown in FIG. 1, the color filter according to the present invention is
The W filters are arranged in a checkerboard pattern, and the R, GB color filters are arranged in a stripe pattern between the W filters. When using a sensor with such a color filter arrangement, a luminance signal is formed by adding the W signals of the three Mizuko lines, and the R2O and B signals of the Mizuko line are used as color signals. If a color filter having such a configuration is used, there is no need to calculate and form the color signal G, and therefore no deterioration of the S/N ratio or false signals will occur. For example, in a sensor with 780 horizontal pixels, the sampling frequency of the luminance signal is 14.3MHz,
A luminance signal in the MHz band can be obtained. Also, since the color signal has a two-pixel period, the number of sampling periods is 4.
．． The frequency is 77 MHz, which is sufficient to obtain a color signal of about 0.5 MHz to 1.5 MHz.

FIG. 2 is a schematic diagram of the area sensor.

The area sensor shown here has a configuration in which sensor signals are read out in both directions of a vertical signal line. Mamizuko line W
The signals are read out to the bottom of the drawing, and similarly, the R, G, and B signals of the Mamizuko line are read out to the top of the drawing, and φ
3. The signal line is transferred using the clock pulse φ2, but the signal line is reset using the clock pulse φ1. Reset pulse φ, c1. with a period different from φ2. φ8c,, φ0. It will be held in

FIG. 3 is a simplified timing chart of the area sensor.

When the number of horizontal pixels is about 780, the clock pulse φ
1. φ2 is 7.16MHz, reset pulse φHCI
l φIII:l + φHC8 becomes a 4.77 MHz pulse. In this embodiment, the two W signals are read out to different signal lines Sf (..., SH2, but if they are read out to the same signal line, the signal clock will be 14.3 MHz.

FIG. 4 is a circuit configuration diagram showing one embodiment of an image sensor using a bipolar sensor.

Note that for the sake of simplicity of explanation, only two rows and three columns of each sensor pixel are shown.

In FIG. 4, S lfl+ Swt is a sensor cell equipped with a W filter, S, ll is a sensor cell equipped with an R filter, So is a sensor cell equipped with a B filter, and Saa is a sensor cell equipped with a B filter.
is a sensor cell equipped with a G filter.

The sensor cell includes a bipolar transistor and a reset M connected to the base of the bipolar transistor.
It consists of an OS transistor and a capacitor that controls the base potential. Mvc+~Mv (6 is a MOS transistor for resetting the vertical signal line, C1~C6
is the capacity for accumulating sensor signals, MHH~MH8
are transfer MOS transistors for transferring the signals accumulated in the capacitors C2 to C6 to the horizontal output line. W1
Signal I Wi times signal MOS transistor MHz, M
The B2 signal, R1 signal, and G signal are output to the horizontal output line through H4, M, and Ia, and the MOS transistor M Hll
MHs+M)ls is output to the horizontal output line.

FIG. 5 is a schematic configuration diagram of a solid-state imaging device to which the present invention is applied.

In the figure, an image sensor 201 in which optical sensors are arranged in an area is subjected to television scanning by a vertical scanning section 202 and a horizontal scanning section 203.

The signal output from the horizontal scanning section 203 is sent to the processing circuit 20.
4 and output as a standard television signal.

Drive pulse φ for vertical and horizontal scanning units 202 and 203
, 4ffil φHI+ φH2, φVll,
φV1. φV2 etc. are supplied by the driver 205. The driver 205 is also limited by the controller 206.

[Effects of the Invention] As described in detail above, according to the solid-state imaging device of the present invention, the first color filters are arranged in a checkered pattern, and the second and third color filters are arranged in a checkered pattern.
, and fourth color filters are arranged in a striped manner between the first color filters, the first, second, third . By obtaining the first to fourth color signals and also obtaining the luminance signal from the photoelectric conversion element of the Mamizuko line provided with the fourth color filter, high-band luminance signals and good color reproducibility are obtained. (, high S
A solid-state imaging device capable of obtaining three primary color signals with a /N ratio can be provided. Further, the conventional color calculation circuit and color temperature correction circuit are not required, the circuit configuration can be simplified, and costs can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a color filter used in the solid-state imaging device of the present invention. FIG. 2 is a schematic diagram of the area sensor. FIG. 3 is a simplified timing chart of the area sensor. FIG. 4 is a circuit configuration diagram showing one embodiment of an image sensor using a bipolar sensor. FIG. 5 is a schematic configuration diagram of a solid-state imaging device to which the present invention is applied. Figure 1

Claims (3)

[Claims] (1) In a solid-state imaging device in which a plurality of color filters are provided in a plurality of photoelectric conversion elements, the first color filter is arranged in a checkered pattern, and the second, third, and fourth color filters are arranged in a checkered pattern. A solid-state imaging device characterized by filters arranged in stripes. (2) The solid-state imaging device according to claim 1, wherein the three-color signals from the two horizontal pixel columns are read out independently. (3) The solid-state imaging device according to claim 1, wherein the one-color signal from the two horizontal pixel columns and the three-color signals are read out using different clocks.