JPS5962285A - Solid-state color image pickup device - Google Patents

Abstract

PURPOSE:To prevent the sresolution of a solid-state image pickup element from being deteriorated, even if the sensitivity is overlapped vertically, by improving the color filter arrangement and signal processing system. CONSTITUTION:An output of the solid-state image pickup element 1 having three-color filters is led to a one picture element delay circuit 2, a two-picture- element delay circuit 3, and a 1H delay circuit. Thus, a signal of 2G+Ye+Cy is obtained at an adder circuit 7 (where; G is a signal corresponding to green color filter, Ye is a signal to green+red color filter and Cy is a signal to green+blue color filter), a signal of 2G+Ye+Cy having a peak in fN/2 (where; fN is a Nyquist limit frequency) is obtained at a subtracting circuit 11, and a signal of 2G+Ye+Cy having a broad band is obtained at an adding circuit 11. Further, R and B signals are added to the said broad band 2G+Ye+Ce signal as G:R:B= 0.59:0.30:0.11 at the adding circuit 15 in a suitable rate and the broad band luminance signal Y is obtained as an output.

Description

【発明の詳細な説明】 く技術分野〉 本発明（〆」−色分解機能を備えたカラー固体撮像装置
に関し、！庁に異々るスペクトル帯域に感応する後数種
の受光素子の配列に関するものである。[Detailed Description of the Invention] [Technical Field] The present invention relates to a color solid-state imaging device with a color separation function, and relates to an arrangement of several types of light receiving elements sensitive to different spectral bands. It is.

〈従来技術〉 ２次元固体４＠豫素子を単板にてカラー化するには、通
常色フィルタを撮像素子上に配置して被写体像を各色成
分毎に空間サンプリングする方法が探られている。この
場合限られた画素を有効に用いてサンプリングの効率を
高めることが望ましく、色フィルタの配列に関して従来
より種々の手法が提唱されている。<Prior Art> In order to colorize a two-dimensional solid-state 4@Y element using a single plate, a method has been explored in which a color filter is usually arranged on an image sensor and a subject image is spatially sampled for each color component. In this case, it is desirable to effectively use limited pixels to increase sampling efficiency, and various methods have been proposed for arranging color filters.

例えば、輝度信号は高い解像度を必要とするの妬対し色
信号は相対的に低い解像度で可能であるというビデオ信
号の特質を利用し、輝度信号の大半を占める緑色（Ｇ）
信号用のＧフィルタのみ水平・垂直の両方向とも１素子
おきの市松状に配置し、その間の位置に赤色（Ｒ）フィ
ルタ及び青色（Ｂ）フィルタを各々繰返しパターンで配
置する手法はり（ｌ率が高く、第１図（ａ）に示すベイ
ヤー配列、第１図（１〕）に示すインターライン配列等
として知られている。しかしこのような配列上の工夫を
行なっても、輝度信号の解像度は、全画素を輝度信号の
ために用いた白黒撮像の場合に比べ低くなる。For example, by utilizing the characteristics of video signals that brightness signals require high resolution, but color signals can be achieved with relatively low resolution, green (G), which occupies the majority of brightness signals, is used.
The method of arranging only the signal G filter in a checkerboard pattern with every other element in both the horizontal and vertical directions, and placing the red (R) filter and blue (B) filter in a repeating pattern between them (the L rate is These are known as the Bayer array shown in Figure 1 (a), the interline array shown in Figure 1 (1), etc. However, even with these arrangements, the resolution of the luminance signal remains low. , is lower than in the case of black-and-white imaging in which all pixels are used for luminance signals.

さらに、フレーム転送型固体撮像素子のように、垂直方
向２画素間にわたり感度の重なりがある場合にＢ１異な
る色信号が混合し、各色信号への分解が不可能となる。Furthermore, when there is overlap in sensitivity between two pixels in the vertical direction, as in a frame transfer type solid-state image sensor, color signals different in B1 are mixed, and separation into each color signal becomes impossible.

従って通常は垂直方向に同一色フィルタを配置し、Ｇ、
Ｒ１Ｂ５色を縦ストライプ状にて水平方向に繰返ｊ−た
配列が用いられる。Therefore, normally filters of the same color are arranged vertically, and G,
An arrangement in which R1B5 colors are repeated horizontally in a vertical stripe pattern is used.

この場合は、水平方向の繰返し周期は白黒撮像の場合に
比べ１／３となり、水平解像度は１／３に低下する。In this case, the repetition period in the horizontal direction is 1/3 compared to the case of monochrome imaging, and the horizontal resolution is reduced to 1/3.

フレーム転送型固体Ｊ＠像素子に適用可能なモザイク状
色フィルタ陀列としては、特開昭５７−３９６８４に透
明（Ｗ）フィルタ、Ｇフィルタ、黄色（Ｙｅ）フィルタ
、ｈびシアン色（Ｃｙ）フィルタを用いた手法が記され
ている（第２図（ａ））。この場合は垂部方向に隣接す
る２画素信号を加算するとＷ−Ｌ　Ｙｅ　ＳＧ　十Ｃｙ
の組合せと、Ｗ　十Ｃｙ　、　Ｇ　−１−Ｙｅの組合せ
が１水平走査期間（ＩＨ）毎１１こ得られる。従ってＲ
及びＢ信号に一２画素周期で空間変調された信号として
Ｉ　ＩＩ毎に交互に得られる。まだ輝度（Ｙ）信号Ｖま
ベースバンド信号として得られ、帯域は白黒撮像時のナ
イキスト限界周波数（ｆ　、、　）からＲ信号ないしＢ
信号の帯域を差し引いた値まで得られる。従って垂直方
向２画素間に感度の重なりがあっても、ＹＳＲ，Ｂ信号
の帯域はそれぞれｆ　−ΔＢ、ΔＢ、ΔＢ（０く△Ｂ≦
ｆ　ｕ／２）−１で得られ、１ 従来の縦方向ストライプ状色フィルタに比べ高い水平解
像度が得られる。As a mosaic color filter array applicable to the frame transfer type solid-state J@ image element, Japanese Patent Application Laid-Open No. 57-39684 discloses a transparent (W) filter, a G filter, a yellow (Ye) filter, and a cyan color (Cy) filter. A method using a filter is described (Fig. 2(a)). In this case, when two pixel signals adjacent to each other in the vertical direction are added, W-L Ye SG 10Cy
, and 11 combinations of W +Cy and G -1-Ye are obtained every horizontal scanning period (IH). Therefore R
and B signals are spatially modulated at 12 pixel periods and are obtained alternately every III. The luminance (Y) signal V can still be obtained as a baseband signal, and the band ranges from the Nyquist limit frequency (f, , ) during monochrome imaging to the R signal or B signal.
The value obtained is obtained by subtracting the signal band. Therefore, even if there is overlap in sensitivity between two pixels in the vertical direction, the bands of YSR and B signals are f - ΔB, ΔB, and ΔB (0ku ΔB ≦
f u/2)-1, and a higher horizontal resolution than conventional vertical striped color filters can be obtained.

しかしながら特開昭５７−３９６８４の手法は次のよう
な欠点を有している。即ちＹ信号の帯域はナイキスト限
界（ｆ　、、　）より低い値であり、ｆＮに近づけばＲ
ないしＢ信号の変調成分が混入して縦縞模様が入る。逆
にｆＮ近傍の白黒画像を摘除した場合には、）・−々い
しＢ信号に偽色信号となって現われる。これら関係を第
２図（ｂ）に示す。さらにとの手法ではＲ及びＢ信号け
ＩＨ毎に欠落するだめＩ　Ｈ毎に補間する必要がある１
、これはＲ及びＢ信号の垂直解像度を低下させることに
なる。However, the method disclosed in Japanese Patent Application Laid-Open No. 57-39684 has the following drawbacks. In other words, the band of the Y signal is a value lower than the Nyquist limit (f,, ), and as it approaches fN, R
Or, a modulation component of the B signal is mixed in, resulting in a vertical striped pattern. On the other hand, if the black and white image near fN is removed, a false color signal appears in the B signal. These relationships are shown in FIG. 2(b). Furthermore, in the above method, since the R and B signals are missing for each IH, it is necessary to interpolate for each IH.
, which will reduce the vertical resolution of the R and B signals.

〈発明の目的〉 本発明は以上のような問題点に鑑みて〃さｈたもので、
垂直方向に感度の重なりがある素子に対して適用可能で
あるにもかかわらず、高解像度等の優れた特性を引き出
すことが可能な色フイルり４／１１列及び信号処理方式
を提供するものである。<Object of the invention> The present invention has been developed in view of the above-mentioned problems.
It provides a color filter 4/11 array and signal processing method that can bring out excellent characteristics such as high resolution even though it is applicable to elements with overlapping sensitivities in the vertical direction. be.

即ちＹ［信号け、ｆη近傍を除きｆＮまで解像可能であ
り、さらに１η付近はＩＨ遅延信号により十分に補間す
ることが可能である。従ってｆＮ−，１：での全域にわ
たりほぼ完全に解像することが可能となる。この場合、
色信号変調成分の混入は完全に除去される。一方、Ｒ及
びＢ信号は常時得られ垂直補間の必要がない。また水平
方向に輝度変化の大きい像を撮像した場合でも、偽色信
号の発生を抑えることが可能である。ここでＲ信号及び
Ｂ信号の帯域は　Ｎ／／２まで得られる。That is, it is possible to resolve up to fN except for the Y signal around fη, and furthermore, the area around 1η can be sufficiently interpolated by the IH delay signal. Therefore, it is possible to almost completely resolve the entire area at fN-,1:. in this case,
Mixture of color signal modulation components is completely removed. On the other hand, R and B signals are always available and do not require vertical interpolation. Further, even when an image with large luminance changes in the horizontal direction is captured, it is possible to suppress the generation of false color signals. Here, the bandwidth of the R signal and B signal can be obtained up to N//2.

〈実＃ｆｉｉ　ｆ、′−１１’、’− 第３図（ａ）及び（ｂ）に本発明の色フイルタ配列実施
例を示す、、色フィルタＶま３種用い、Ｇ　、　Ｇ＋Ｒ
＝Ｙｅ、Ｇ　−１−Ｂ　＝　Ｃｙの組合せとする０各水
平列内では４画素周期の繰返（２醒列となっており、１
周期内ではＧフィルタが隣接り一で２画素存在し、残り
の位置にｔ／′ｉＹｅフィルタ及びｃｙフィルタが各１
画素ずつ、ないし同一フィルタのみ２画素存在する。ま
だ各垂直列内では４画素周期の繰返し配列となっており
、１周期内ではＧフィルタが隣接して２画素存在し、残
りの位置にはＹｅフィルタ及びｃｙフィルタが各１画素
存在する。<Actual #fii f, '-11', '- Figures 3 (a) and (b) show examples of color filter arrays of the present invention. Three types of color filters are used: G, G+R.
=Ye, G -1-B = Cy combination 0 In each horizontal column, 4 pixel periods are repeated (2 pixel columns, 1
Within the period, there are two adjacent pixels of G filters, and one t/'iYe filter and one cy filter each in the remaining positions.
For each pixel, there are only two pixels of the same filter. Each vertical column is still arranged in a repeating array with a period of four pixels, and within one period there are two adjacent pixels of the G filter, and in the remaining positions there are one pixel each of the Ye filter and the cy filter.

前記色フィルタと相合ぜた固体撮像素子の信号の読み出
１−は次のように行なう。力お以下では第３図（ａ）の
場合のフィルタ配列について説明を行なうが、第３図０
〕）についても同様に議論することが可能である。Reading 1- of the signal of the solid-state image sensor combined with the color filter is performed as follows. In the following, we will explain the filter arrangement in the case of Fig. 3(a).
]) can be similarly discussed.

第３図（ａ）において、奇数フィールドでは第（４ｎ−
３）行と第（４］１−２）行、第（４ｎ−１）行と第４
ｎ行、・が２行間時に読み出されかつ同一垂直列上０２
２画素信は加算されて出力される。次に偶数フィールド
では第（４ｎ−２）行と第（４ｎ−１）行、第４１１行
と第（４ｎ＋１　）行、　・が２行間時に読み出さＩｉ
かつ同一垂直列上の２画素信号は加算されて出力される
。結局、実時間１１片号（ＯＨ）は第４図（ａ）に示し
だ信号列となる。この場合隣接画素信号間で差を取ると
Ｒ及びＢ信号が１画素信号毎に交互に得られる。即ち、
Ｒ信号及びＢ信号１ｄ’ｌ信号列のみで同時に得られ、
その帯域は白黒撮像時の１／　であるｆＩＩ／２まで得
られる。In FIG. 3(a), in the odd field, the (4n-th
3) row and (4) 1-2) row, (4n-1) row and 4th
n row, . is read out between two rows and on the same vertical column 02
The two pixel signals are added and output. Next, in the even field, the (4n-2)th row and the (4n-1)th row, the 411th row and the (4n+1)th row, and ・ are read out between two rows.Ii
Two pixel signals on the same vertical column are added and output. In the end, the real time signal number 11 (OH) becomes the signal train shown in FIG. 4(a). In this case, by taking the difference between adjacent pixel signals, R and B signals are obtained alternately for each pixel signal. That is,
R signal and B signal can be obtained simultaneously with only 1d'l signal train,
The band can be obtained up to fII/2, which is 1/2 that of monochrome imaging.

一方、ベースバンド成分として得らｈ−る輝度信号はそ
のままでは　ＩＪ／２の所にＲ及びＢ信号の変調成分が
混入する。従って　１喝を中心とする±ΔＢの帯域（Δ
Ｂ；Ｒ及びＢ信号の帯域）の成分を除去する。この帯域
の輝度信号はＯＨ信号とＩＨ遅延信号（ＩＨ）との加算
により得られる。即ち、ｆＮ、／２近傍の高域信号は一
般に垂直相関度が高いから、ＯＩ−Ｉ信号と１　ｉＩ遅
延信号の加算信号により近似することが可能であり、こ
のうち１１滴を中心とする士△Ｂの帯域成分を抽出し、
前記した当該帯域除去輝度信号番・ｃ二加算ずｈばｆ’
＋ｖまでの広帯域輝度−＋＝号を得ることが可能となる
。On the other hand, if the h-luminance signal obtained as a baseband component is left as it is, the modulation components of the R and B signals will be mixed in at IJ/2. Therefore, the band of ±ΔB (Δ
B; R and B signal bands) are removed. The luminance signal in this band is obtained by adding the OH signal and the IH delay signal (IH). In other words, since the high-frequency signal near fN, /2 generally has a high degree of vertical correlation, it can be approximated by the sum signal of the OI-I signal and the 1 iI delayed signal, and among these, the signal centered on 11 drops Extract the band component of △B,
The above-mentioned band-removed luminance signal number/c2 addition/hbaf'
It becomes possible to obtain a wide band luminance of −+= up to +v.

上記操作の実施例を以下して述べる。第４図（ｂ）、（
ｃ）及び（ｄ）に、第４図（ａ）に示したＯ　Ｈ信号の
１画素遅延信号（ＩＥ）、２画素遅延信号（２Ｅ）、及
びＩＨ遅延信号（１■（）を示す。ＯＨ信号からＩＥ倍
信号減算すると第４図（ｅ）に示すようにＲ，Ｂ信号が
画素毎に交互に得られる。但し、符号は２画素毎に反転
する。従って例えば同期検波回路により正符号化し、Ｒ
信号とＢ信号に分配することによシ高解像度のＲ信号、
Ｂ（Ｍ号が得られる。一方、輝度信号によＯＨ信号と２
Ｅ信号を加算することにより第４図（ｆ）に示すように
画素毎に常に２　Ｇ＋Ｙ　ｅ　−１−Ｃｙ信号が得られ
る。但し、この場合の信号帯域は、にｆＮ／／２丁応答
がＯとなる特性になる。An example of the above operation will be described below. Figure 4(b), (
c) and (d) show a 1-pixel delayed signal (IE), a 2-pixel delayed signal (2E), and an IH delayed signal (1) of the OH signal shown in FIG. 4(a).OH When the IE multiplied signal is subtracted from the signal, R and B signals are obtained alternately for each pixel as shown in FIG. ,R
High-resolution R signal by dividing into signal and B signal,
B (M number is obtained.On the other hand, the OH signal and 2
By adding the E signals, a 2 G+Y e -1-Cy signal is always obtained for each pixel as shown in FIG. 4(f). However, in this case, the signal band has a characteristic in which the response to fN//2 is O.

次に、ＯＩＩ信号とＩ　Ｈ信号を加算すると画素毎に常
に２Ｇ−１−Ｙｅ＋Ｃｙ信号が得られる○この信号は同
一垂直列上の画素の加算信号であるから、垂直解像度に
影響する低域成分を除けば高解像度輝度信号である。従
ってＯｆ（＋Ｉ　Ｈ信号からＯＨ＋ＩＨ信号を２画素遅
延したイ計号（’ＯＨ−１−Ｉ　Ｈ）・（２Ｅ）を減算
す−ｈば、 にｆ　ｉ’、（でピークを持ち、０とｆ、１でＯとなる
応答特性になる。従ってこの信号を前記ＯＨ＋２Ｅ信号
に加算すればｆＨまでの帯域全域にわたって高い応答特
性を持つ２Ｇ−１−Ｙｅ＋Ｃｙ信号が祷られる０最終的
な輝度信号は２Ｇ＋Ｙｅ＋Ｃｙ信号にＲ信号及びＢ信号
を適宜加算し、Ｇ：Ｒ：Ｂ＝０．５９：０．３０：０１
１となるようにすれば色再現性も良好な高帯域の輝度信
号Ｙｆ３：得ることができる。以上の結果、Ｒ，Ｂ、Ｙ
信号の帯域は第５図（ｃ）に示す範囲まで・帰られるこ
とが判明する。Next, by adding the OII signal and the IH signal, a 2G-1-Ye+Cy signal is always obtained for each pixel. Since this signal is a sum signal of pixels on the same vertical column, it contains low-frequency components that affect vertical resolution. Except for this, it is a high-resolution luminance signal. Therefore, if we subtract from the Of(+IH signal the 2-pixel delay of the OH+IH signal ('OH-1-IH)・(2E), we get f i', (which has a peak at 0 and The response characteristic becomes O at f, 1. Therefore, if this signal is added to the OH+2E signal, a 2G-1-Ye+Cy signal with high response characteristics over the entire band up to fH is expected.0 The final luminance signal is Appropriately add R signal and B signal to 2G+Ye+Cy signal, G:R:B=0.59:0.30:01
1, a high-band luminance signal Yf3 with good color reproducibility can be obtained. The above results, R, B, Y
It turns out that the signal band extends to the range shown in FIG. 5(c).

第６図は以上に述べた信号処理を実現するだめの回路ブ
ロック図を示１ｈ二ものである。第３図（ａ）に示しだ
色フィルタを備えた固体撮像素子１の出力信号は分岐さ
れ、その一部は１画素遅延回路２．２画素遅延回路３、
ＩＨ遅延回路４へ各々導かれる。減算回路６では撮像素
子１の分岐出力信号から遅延回路２の出力信号が減算さ
れ同期検波回路１２へ導かｉしる。このときの信号波形
は第４図（ｅ）に相当する。（σ・波回路１２では信号
に同期して２画素お・きに符号を反転する機能を有し、
全て正符号のＲＳＢ信号を出力し７、次段のサンプリン
グ回路１３及び１４へ導く０サンプリング回路１３では
Ｒ信号のみが、サンプリング回路１４ではＢ信号のみが
サンプリングされ、それぞれ増幅器を介してＲ信号、Ｂ
信号が出力される。FIG. 6 shows a circuit block diagram for realizing the signal processing described above. As shown in FIG. 3(a), the output signal of the solid-state image sensor 1 equipped with a color filter is branched, and a part of it is divided into a 1-pixel delay circuit 2, a 2-pixel delay circuit 3,
They are each guided to the IH delay circuit 4. In the subtraction circuit 6, the output signal of the delay circuit 2 is subtracted from the branched output signal of the image sensor 1, and the result is guided to the synchronous detection circuit 12. The signal waveform at this time corresponds to FIG. 4(e). (The σ wave circuit 12 has a function of inverting the sign every two pixels in synchronization with the signal,
The 0 sampling circuit 13 outputs RSB signals with all positive signs and leads them to the next stage sampling circuits 13 and 14. In the 0 sampling circuit 13, only the R signal is sampled, and in the sampling circuit 14, only the B signal is sampled. B
A signal is output.

一方、遅延回路３の出力は撮＠素子１の分岐出力と加算
回路７で加算され２Ｇ−１−Ｙｅ＋Ｃｙ信号を得る。こ
の場合の信号波形ｉ［４図（ｆ）にイ目自する。On the other hand, the output of the delay circuit 3 is added to the branch output of the sensor 1 in an adder circuit 7 to obtain a 2G-1-Ye+Cy signal. In this case, the signal waveform i [see Fig. 4 (f)].

まだ第５図（ａ）に示す周波数応答特性である２、次に
、Ｌ　Ｈ遅延回路４の出力は５３−岐さＪし、一方は加
算回路８へ導かれ、撮ｒ象素子１の分岐出力と加算され
る。この、場合の信号波形は第４図（ｇ）に相当する。2, which still has the frequency response characteristic shown in FIG. is added to the output. The signal waveform in this case corresponds to FIG. 4(g).

遅延回路４の他の分岐出力は２画素遅延回路３′を介し
て加算回路９へ導かｉｔ、遅延回路３からの信号と加算
される。この場合の信号波形は第一４図１ｇ）において
２画素遅延した信号に相当する。The other branch output of the delay circuit 4 is led to the adder circuit 9 via the two-pixel delay circuit 3' and added to the signal from the delay circuit 3. The signal waveform in this case corresponds to the signal delayed by two pixels in FIG. 4 (1g).

減算回路１０では前記加算回路８の出力信号から加算回
路９の出力信号が減算さｉｚ、第５同側に示すようにｆ
！糠にピークを持つ２Ｇ１−ＹｃＩＣｙ信号が得られる
。加算回路１１では、前記加算回路７からのｆ、滴に負
のピークを持つ２Ｇ＋Ｙｅ＋Ｃｙ信号と、減算回路１０
からのｆ１１／２にピークを持つ２Ｇ十Ｙｅ十ＣＶ信号
が加算され、広帯域の２Ｇ＋ＹｅＣｙ信号が得られる。In the subtracting circuit 10, the output signal of the adding circuit 9 is subtracted from the output signal of the adding circuit 8.
! A 2G1-YcICy signal having a peak in bran is obtained. The addition circuit 11 receives the f from the addition circuit 7, the 2G+Ye+Cy signal having a negative peak in the droplet, and the subtraction circuit 10.
The 2G + Ye + CV signals having a peak at f11/2 are added to obtain a broadband 2G+YeCy signal.

との信号は増幅器を介して加勢回路１５へ導かれる。加
算回路１５ではＧ：Ｒ：Ｂ＝０．５９：０．３０：０．
１１となるよう前記広帯域２Ｇ−ｌ−Ｙｅ＋Ｃｙ信号に
前記Ｒ信号及びＢ信号が適癌な比率で加算さり、広帯域
輝度信号Ｙが出力されろ。The signal is led to the auxiliary circuit 15 via an amplifier. In the adder circuit 15, G:R:B=0.59:0.30:0.
The R signal and the B signal are added to the wideband 2G-l-Ye+Cy signal at an appropriate ratio so that the brightness signal Y becomes 11, and a wideband luminance signal Y is output.

第７図は本発明を実現するだめの別の回路ブロック図を
示したものである。Ｒ及びＢ信号を得る回路は第６図の
場合と同一である。輝度信号を得るには次のように行な
う。第３図（ａ）の色フィルタを備えだ固体撮像素子１
からの分岐出力の１つはｆηに負のピークを持つ帯域除
去フィルタ１６を通すととによりＲ，Ｂ信号変調成分を
除去した２　Ｇｌ−Ｙ　ｅ　−＋−Ｃｙ信号を得る。一
方、固体撮像素子１の分岐２出力のうち一方は直接、他
方はＩ　Ｉ−１遅延回路４を介して加算回路８へ導かれ
画素毎に加算されて、垂直解像度は低いが高い水平解像
度を持つ２Ｇ−１−Ｙｅ　ｌ−ＣＶ信号を得る。この信
号をｆ　ｕ７．、にピークを持つ帯域通過フィルタ１７
を通すことにより前記帯域除去フィルタ１６からの信号
を補イｔ′ｔするイ菖号を得る。従ってフィルタ１６及
・び１７からの信号を加算回路１１で加算することによ
り、ｆＮまで応答の劣化のない広帯域の２Ｇ＋Ｙｅ十Ｃ
ｙ信号が得られる。この後輝度信号を得る、回路は第６
図の場合と同一であり、前記２Ｇ＋Ｙｅ＋Ｃｙ信号にＲ
信号及びＢ信号を適宜加算することにより広帯域輝度信
号Ｙが得られる。FIG. 7 shows another circuit block diagram for realizing the present invention. The circuit for obtaining the R and B signals is the same as in FIG. To obtain the luminance signal, proceed as follows. Solid-state image sensor 1 equipped with the color filter shown in FIG. 3(a)
One of the branched outputs is passed through a band-rejection filter 16 having a negative peak at fη, thereby obtaining a 2 Gl-Y e −+-Cy signal from which the R and B signal modulation components have been removed. On the other hand, one of the branch 2 outputs of the solid-state image sensor 1 is led directly to the adder circuit 8 through the I-1 delay circuit 4 and added for each pixel, resulting in a high horizontal resolution although the vertical resolution is low. Obtain a 2G-1-Yel-CV signal with This signal is f u7. , a bandpass filter 17 having a peak at
By passing the signal through the band-elimination filter 16, a signal which complements the signal from the band-removal filter 16 is obtained. Therefore, by adding the signals from the filters 16 and 17 in the adder circuit 11, a wide band of 2G+Ye+C with no response deterioration up to fN can be obtained.
A y signal is obtained. After this, the circuit obtains the luminance signal at the sixth
This is the same as the case shown in the figure, and R is applied to the 2G+Ye+Cy signal.
A wideband luminance signal Y is obtained by appropriately adding the signal and the B signal.

以上の信号処理方式においては水平方向に輝度変化の大
きい光像、殊にｆｌ＋／２の空間周波数の像においては
ＲないしＢ信号に偽信号が生じる。しかしながらこの偽
信号は以下の手法により消去可能である。In the above signal processing method, a false signal occurs in the R or B signal in an optical image with a large change in luminance in the horizontal direction, especially in an image with a spatial frequency of fl+/2. However, this false signal can be eliminated by the following method.

第８図に示す状況においては、奇数フィールドｆｌｌｌ
ｌでＲ信号に、偶数フィールド側でＢ信号に偽信号が生
じる。いま賃Ｓ数フィールトイ［１すを考えると、第］
ηライン走査時には同期検波後のＲ信号に十の偽信号が
生じ、第１ｎ−１ライン走査時には−の偽信号が生じて
いる。従って両者の加算（ｉ号を取れば偽信号は消失す
る。まだ本来のＲ信号の場合には正しく再生される。偶
数フィールド側も上記操作をＢ信号に適用することによ
り、偽のＢ信号は消失する。但し、以上の操作はＲ及び
Ｂ信号の垂直Ｍ＠度を劣化させる。従って実際にｄ：次
のようとする。In the situation shown in FIG.
A false signal occurs in the R signal at 1, and a false signal occurs in the B signal at the even field side. Now pay S number feel toy [considering 1 S]
During η line scanning, a 10 false signal occurs in the R signal after synchronous detection, and a - false signal occurs during 1n-1 line scanning. Therefore, if you add the two (take the i number), the false signal will disappear.If it is still the original R signal, it will be reproduced correctly.On the even field side, by applying the above operation to the B signal, the false B signal will be removed. However, the above operation degrades the vertical M@ degree of the R and B signals.Actually, d: is as follows.

第９図は偽色信号消去のだめの回路ブｒｌｌツク図であ
る。固体カラー撮像素子１の１１」力信号から同信号を
遅延回路２により１画素遅延した信号を差し引き、２画
素毎に符号反転する同期検波回路１２によりＲＳＢ検波
信号を得る。また撮像素子１の出力信号を遅延回路４に
よりＩ　Ｈ遅延さぜた信号から、同信号をさらに遅延回
路２′により１画素遅延させた信号を差し引き、２画素
毎に符号反転する同期検波回路１２′によりＩ　Ｈ遅延
したＲ、Ｂ検波信号を得る。同期検波回路１２の出力と
１２′の出力を加算することにより偽色のないＲ，Ｂ信
号を得る。一方、撮像素子１の出カイ計号と同信号を遅
延回路３によシ２画素遅延した４８号とを加算して２Ｇ
−１−Ｙｅ−１−Ｃ：ｉ’倍信号得る。また、撮像素子
１の出力信号を遅延回路４により１　ｆｌ遅延した信号
と、同信号を遅延回路３′により２画素遅延した信号と
を加算して、Ｉ　Ｈ遅延した２Ｇ−ｆ−Ｙｅ＋Ｃｙ信号
を得る。２Ｇ十Ｙｅ＋Ｃｙ信号から同信号をＩＨ遅延し
た信号を差し引くことにより垂直輪郭信号を得る。FIG. 9 is a circuit block diagram for eliminating false color signals. A signal delayed by one pixel by a delay circuit 2 is subtracted from the 11'' output signal of the solid-state color image sensor 1, and an RSB detection signal is obtained by a synchronous detection circuit 12 which inverts the sign every two pixels. Furthermore, a synchronous detection circuit 12 subtracts a signal obtained by further delaying the same signal by one pixel by a delay circuit 2' from a signal obtained by IH delaying the output signal of the image sensor 1 by a delay circuit 4, and inverts the sign every two pixels. ' to obtain IH-delayed R and B detection signals. By adding the output of the synchronous detection circuit 12 and the output of the synchronous detection circuit 12', R and B signals without false colors are obtained. On the other hand, the output signal of the image sensor 1 and the signal No. 48, which is delayed by 2 pixels by the delay circuit 3, are added together to produce 2G.
-1-Ye-1-C: Obtain i' times signal. Also, by adding the output signal of the image sensor 1 delayed by 1 fl by the delay circuit 4 and the signal delayed by 2 pixels by the delay circuit 3', a 2G-f-Ye+Cy signal delayed by IH is obtained. obtain. A vertical contour signal is obtained by subtracting a signal obtained by IH delaying the same signal from the 2G+Ye+Cy signal.

この輪郭信号を前記偽色消去したＲ、Ｂ信号に付加して
、垂直解像度を改善し７だ偽色消去Ｒ，Ｂ信号を得、Ｒ
及びＢ信号を各々別個にサンプリングして目的とするＲ
信号、Ｂ信号を得る。This contour signal is added to the false color canceled R and B signals to improve the vertical resolution and obtain the false color canceled R and B signals.
and B signals separately to obtain the desired R
Get signal, B signal.

〈効果〉 以上説明してきたように、本発明によれば、垂直方向２
画素にわたり感度の重なりがある固体撮像素子において
も、高い水平・垂直解像度を持ち、相互の干渉もほとん
どないＲ，ＢＳＹ信号を得ることが可能となる。また使
用色フィルタはＧ、Ｙｅ。<Effects> As explained above, according to the present invention, vertical direction 2
Even in a solid-state image sensor in which sensitivities overlap across pixels, it is possible to obtain R and BSY signals with high horizontal and vertical resolution and almost no mutual interference. The color filters used are G and Ye.

Ｃｙの３色で十分であり、ＧフィルタをＹｅフィルタと
Ｃｙフィルタの重ねて形成すれば２色で構成できる利点
を合わせ持っている。さらに１６（色フイ）レタの場合
に比べ光の利用効率が高く、感度が高められることは言
うまでもない。Three colors of Cy are sufficient, and if the G filter is formed by overlapping the Ye filter and the Cy filter, it has the advantage that it can be composed of two colors. Furthermore, it goes without saying that the light utilization efficiency is higher and the sensitivity is higher than in the case of 16 (color filters).

ここで、垂直方向の感度の重なりは、フレーノ・転送型
撮像素子のように構造的なものであっても、光学的なも
のであっても、さらに駆動方法により達成したものであ
っても、垂直２画素間にわたるものである限りはすべて
本発明が適用可能である。Here, the overlap in sensitivity in the vertical direction may be structural, as in Freno transfer type image sensors, optical, or achieved by a driving method. The present invention is applicable to any area as long as it extends between two vertical pixels.

なお、以上においては第３図（ａ）、（ｂ）に示す色フ
ィルタを固体撮像素子上に装置した場合を例に取り説明
してきだが、固体撮像素子の名画素自体が前記色フィル
タ配列に相当する分光特性を備える場合に対しても同様
に議論することができる。In the above explanation, we will take as an example the case where the color filters shown in FIGS. 3(a) and 3(b) are installed on a solid-state image sensor, but the pixel of the solid-state image sensor itself corresponds to the above-mentioned color filter array. A similar argument can be made for the case where the spectral characteristics are as follows.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図及び第２図は従来用いられている色フィルタ配列
の例で、第１図は各画素信号を独立して読み出せる場合
に適用可能な例、第２図は垂直方向に感度の重カリがあ
る場合に適用可能な例であり（ａ）は色フィルタ蘭列を
示す図、（ｂ）はＹ、Ｒ，Ｂ信号の帯域を示す図、第３
図（ａ）及び（ｂ）は本発明による色フィルタ配列を示
す図、第４図は本発明による信号処理のタイミングを示
す図、第５図は本発明により得ちれる信号の周波数応答
を示し、（ａ）及び（ｂ）は信号処理の途中における２
信号の応答図、（ｃ）は最終的なＹＳＲ，Ｂ信号の帯域
を示す図、第６図及び第７図は名々本発明を実現す、る
ための回路ブロック図、第８図及び第９図は偽色信号を
消去する手法を示すもので、第８図はタイミング図、第
９図は回路ブロック図を示す。 １：固体カラー撮像素子、２．２′、１画素遅延回路、
３．３′：２画素遅延回路、４：ＩＨ遅延回路、６．７
．８．９．１０．１１．１５：加減算回路、１２．１２
′：同期検波回路、１３．１４：サンプリング回路、１
６：帯域除去フィルタ、１７：帯域通過フィルタ。 代理人　弁理士　福　士　愛　彦（他２名）ｔσノ ４７ノ 第２ ｔσノ 第 （ｂ） 第　／ｌス１ ０　　　　　　　　　ｆｔｖ　　　鴇線（ｂ） 図 （ｂ） ３１！１Figures 1 and 2 show examples of conventionally used color filter arrays. Figure 1 is an example that can be applied when each pixel signal can be read out independently, and Figure 2 is an example where the sensitivity is stacked vertically. This is an example that can be applied when there is potency, and (a) is a diagram showing a color filter sequence, (b) is a diagram showing bands of Y, R, and B signals, and
Figures (a) and (b) are diagrams showing the color filter array according to the present invention, Figure 4 is a diagram showing the timing of signal processing according to the present invention, and Figure 5 is a diagram showing the frequency response of the signal obtained according to the present invention. , (a) and (b) are 2 in the middle of signal processing.
Signal response diagram, (c) is a diagram showing the final YSR and B signal bands, Figures 6 and 7 are circuit block diagrams for realizing the present invention, and Figures 8 and 7 are FIG. 9 shows a method for eliminating false color signals, FIG. 8 shows a timing diagram, and FIG. 9 shows a circuit block diagram. 1: Solid-state color image sensor, 2.2', 1 pixel delay circuit,
3.3': 2 pixel delay circuit, 4: IH delay circuit, 6.7
．． 8.9.10.11.15: Addition/subtraction circuit, 12.12
': Synchronous detection circuit, 13.14: Sampling circuit, 1
6: Band-removal filter, 17: Band-pass filter. Agent Patent attorney Aihiko Fukushi (and 2 others) tσ no. 47 no. 2 tσ no. 2 (b) No. /l s1 0 ftv Tokisen (b) Figure (b) 31!1

Claims (1)

【特許請求の範囲】 ■）水平・垂直方向に配列された受光素子群からなる撮
像装置において、各受光素子は第１スペクトル帯域に感
応する第１の受光素子、第１スペクトル帯域と第２スペ
クトル帯域に感応する第２の受光素子、第１スペクトル
帯域と第３スペクトル帯域に感応する第３の受光素子の
いずれかにより構成されており、さらに垂直方向に隣接
する２素子を組とし、該２素子組が水平方向に隣接する
任意の４組内においてｄ、前記第１の受光素子２素子か
らなる第１の組、第１の受光素子と第２の受光素子から
なる第２の組、第１の受光素子と第３の受光素子からな
る第３の絹、及び第２の受光素子と第３の受光素子から
なる第４の組がそれぞれ各１組存在し、かつ第１の組と
第４の組は前記４．１１内において水平方向に間に１絹
おいて隔てた位置を占め、第２の組と第３の組は前記４
ｍ内の残余の位置を占めてなることを特徴とする固体カ
ラー撮像装置、。 ２）垂直方向に隣接する任意の４素手組内においては、
常に前記第１の受光素子が２素子、第２の受光素子及び
第３の受光素子が各々１素子存在することを特徴とする
特許請求の範囲第１項記載の固体カラー撮像装置。 ３）前記第１スペクトル帯域は緑色帯域、第２スペクト
ル帯域は赤色帯域、第３スペクトル帯域は青色帯域とな
ることを特徴とする特許請求の範囲第１項ないし第２項
記載の固体カラー掃像装置。[Claims] ■) In an imaging device consisting of a group of light receiving elements arranged in horizontal and vertical directions, each light receiving element is a first light receiving element sensitive to a first spectral band, a first spectral band and a second spectral band. It is composed of either a second light-receiving element sensitive to a band, a third light-receiving element sensitive to a first spectral band and a third spectral band, and two vertically adjacent elements are formed into a set, and the two Among any four horizontally adjacent element sets, d, a first set consisting of two first light receiving elements, a second set consisting of a first light receiving element and a second light receiving element, and a second set consisting of a first light receiving element and a second light receiving element; There is one set each of a third set consisting of the first light receiving element and the third light receiving element, and a fourth set consisting of the second light receiving element and the third light receiving element. The 4th set occupies horizontally spaced positions within the 4.11 space, and the 2nd and 3rd sets occupy positions within the 4.11 space.
A solid-state color imaging device, characterized in that the solid-state color imaging device occupies a residual position within m. 2) In any vertically adjacent four-arm pair,
2. The solid-state color imaging device according to claim 1, wherein there are always two first light-receiving elements, one second light-receiving element, and one third light-receiving element each. 3) The solid-state color sweeping image according to claim 1 or 2, wherein the first spectral band is a green band, the second spectral band is a red band, and the third spectral band is a blue band. Device.