JP3323494B2 - Imaging device and control method of imaging device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup apparatus, and more particularly to an image pickup apparatus and a control method of the image pickup apparatus, which change an area from which a signal of an image pickup element is read.

[Conventional technology]

In recent years, the size and weight of the imaging device have been reduced, and the zoom magnification of the lens has also been increasing, so that image blur due to camera shake tends to occur during hand-held shooting.
A conventional technique for suppressing this image blur is disclosed in
The method described in 143330 is known. The above technology detects the shake of an imaging device with a rotating gyro and moves the optical system from the lens to the imaging device based on the detection result, or separates the signal transfer of the imaging device into high-speed transfer and normal transfer , Which controls the number of high-speed transfers, and the latter is characterized in that the size of the device can be reduced.

[Problems to be solved by the invention]

However, in the above-described related art, no consideration is given to two-row simultaneous reading in which two pixels in the vertical direction of the image sensor are simultaneously read. The simultaneous reading of two rows is an indispensable method for eliminating the afterimage of a frame. In particular, if the number of high-speed transfers is increased or decreased while performing the simultaneous reading of two rows, the area of pixels for normal transfer is at least two pixels. Since the image can be moved only in units of pitch, there is a problem that an image in which the image shake is suppressed becomes an awkward movement.

An object of the present invention is to make it possible to move an area of a pixel to which normal transfer is performed at a one-pixel pitch while performing two-row simultaneous reading, so that the image moves smoothly.

[Means for solving the problem]

In order to achieve the above object, an image sensor, a scan pulse generation circuit for supplying a scan pulse for signal transfer to the image sensor, and a scan pixel area control circuit for supplying a control signal to the scan pulse generation circuit are provided. The combination of two vertically adjacent pixels that are simultaneously read out by the control signal are sequentially shifted by one pixel pitch.

[Action]

If the combination of two vertically adjacent pixels to be read simultaneously is gradually shifted at a one-pixel pitch, the area of pixels to which a signal is normally transferred can be moved at a one-pixel pitch, so that the motion of an image becomes smooth.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to FIG. In FIG. 1, reference numeral 100 denotes an image sensor, 101 denotes a signal processing circuit, 102 denotes a transfer pulse generating circuit, and 103 denotes a scanning pixel area control circuit. Also, a specific example of the transfer pulse generation circuit 102 is shown by a broken line in FIG. 3, where 104 is a synthesis circuit, 105 is a normal transfer pulse generation circuit, and 106 is a high-speed transfer pulse generation circuit.

First, the operation of the image sensor 100 will be described. The image pickup device is roughly classified into a CCD type and a MOS type, and FIG. 2 shows a typical CCD type image pickup device. In the figure, 1 is a photodiode and 2 is a vertical CC.
D and 3 are horizontal CCDs, and the photodiodes 1 are arranged in m rows and n columns, and the numbers of rows and columns are indicated by subscripts. The signal charges accumulated in the photodiode 1 are transfer pulses φ _{V1 to} φ _V4
Are transferred to the vertical CCD 2 and then sequentially transferred to the horizontal CCD, and are output by a horizontal transfer pulse (not shown). The state of the signal transfer will be described with reference to FIGS. 3 to 6, paying particular attention to the simultaneous reading of two rows. Figure 3 shows a signal S _2i-1 of the photodiode of the (2i-1) row, the first (2i) the timing chart of transfer pulses when to simultaneously read the signals S _2i row of photodiodes. Here, i is a natural number. Vertically from the photodiode 1 in the period T ₁
The signal Si is transferred to CCD 2, it is transferred to the horizontal CCD3 at time t ₁ ~t _8. This is shown in FIG. Signal S _2i-1 and S _2i at time t ₁
, And the signals S ₁ and S ₂ are transferred to the horizontal CCD ₃ and read out sequentially by time t ₈ . The same transfer is performed for the next horizontal period, and the time t ₉
, The signals S ₃ and S ₄ are transferred to the horizontal CCD ₃ . Figure 5 shows the (2
i) shows the signal S _2i rows of the photodiode, a second (2i + 1) timing chart of transfer pulses when to simultaneously read the signals S _{2i + 1} of the row of photodiodes. As shown in FIG. 6, the state of signal transfer is read out in a combination shifted by one row from FIGS. Normally, the signal transfer shown in FIGS. 3 and 4 is performed in an odd field, and the signal transfer shown in FIGS.
The signal transfer shown in FIG. 6 is performed to perform interlace.

Next, a typical MOS type imaging device will be described. In the figure, 4 is a horizontal shift register, 5 is a horizontal start pulse (HIN) input terminal, 6 and 7 are horizontal clock (H1, H2) input terminals, 8 is a vertical shift register, and 9 is a vertical start pulse (VIN) input. Terminals 10, 11 are vertical clock (V1, V2) input terminals, 12, 13 are field pulse (FA, FB) input terminals, 14
Is a photodiode, 15 to 19 are MOS switches, and 20 is a signal output terminal. Also, the luminance signal is as shown in FIG.
It is obtained by adding the respective output signals.

The reading of signals will be described with reference to FIGS. When the vertical start pulse VIN is input, the vertical clocks V1 and V2
The pulse Pi is sequentially output from the vertical shift register 8 in the cycle of. This pulse Pi is distributed by the MOS switches 15 and 16 according to the polarities of the field pulses FA and FB to become a pulse Qi, and the photodiodes in the (2i-1) th row and the (2i) th row
The fourteen signals S _2i-1 and S _2i are selected at the same time, and are sequentially read out by a pulse from the horizontal shift register 4, although not shown in FIG. In FIG. 10, the field pulses FA, F
The polarity of B is inverted, the combination of the rows selected by the pulse Qi is shifted by one row, and the signals S _2i and S _{2i + 1} of the photodiodes in the (2i) -th and (2i + 1) -th rows are output simultaneously. In normal signal reading, interlacing is performed by reading the signal shown in FIG. 9 in an odd field and reading the signal shown in FIG. 10 in an even field.

Next, a case where high-speed transfer is combined will be described.
FIG. 11 shows the signal output in the transfer pulse φ _V4 (A) of the A field and the transfer pulse φ _V4 (B) of the B field in FIG. 3 and FIG. 5 with the transfer pulse φ _V4 as a representative. In φ _V4 (A, N) φ _V4 (B, N), in which N high-speed transfer pulses are added to this transfer pulse, the signal is
As shown in FIG. 12, data is read out by normal transfer with a shift of 2N rows. The scanning pixel area at this time starts from the 2Nth row. FIG. 13 shows a case where the scanning pixel area is shifted by one line. In the field A in FIG. 13, signals are read out in a combination shifted by one row by using the same transfer pulse φ _V4 (B, N) as in the field B in FIG. In the B field of FIG. 13, Fig. 12 of the transfer pulse φ _V4 (A, N) transfer pulse _{φ V4 (A, N + 1} ) added one fast transfer by using, in one line shift in combination The signal is read.

Next, the case of a MOS type image sensor will be described. 14th
The figure shows the signal reading when N high-speed pulses are added, as represented by the pulses FA, FB, VIN, V1 in FIGS. 9 and 10. As in the case of the CCD type, by adding N high-speed pulses, the scanning pixel area starts from the second N rows. Here, FIG. 15 shows a case where the scanning pixel area is shifted by one line. In the field A in FIG. 15, signals are read out in a combination shifted by one row by using the pulse in the field B in FIG. In the B field of FIG. 15, a signal is read out in a combination shifted by one row by adding one high-speed pulse to the pulse of FIG.

Since interlacing is not performed in the horizontal direction, the number of high-speed transfers may be simply changed, and a description thereof will be omitted.

In summary, the normal transfer pulse control signal F shown in FIG. 1 controls which field of the normal transfer pulse is supplied to the image sensor 100, and the high-speed pulse number control signals m and n control the vertical and vertical pulse numbers, respectively. What is necessary is just to control the number of horizontal high-speed pulses. For example, FIG. 16 shows a flowchart in the case of shifting one line in one vertical direction. According to this flowchart, the transfer pulse generation circuit 102 transfers the transfer pulse P (F, m,
Output n). Here, F indicates whether the normal transfer pulse is for the A field or the B field, and m and n indicate the number of vertical and horizontal high-speed pulses, respectively. Here, a case where one line is shifted in one vertical direction is shown, but the same can be applied to a case where the line is shifted in the opposite direction or a plurality of lines. Further, as is apparent from the above description, when the scanning pixel area is changed continuously over two fields, the normal transfer pulse for the A field or the B field is continuously supplied to the image sensor 100. Will do.

Switching of the normal transfer pulse and switching of the number of high-speed transfer pulses are performed in the vertical flyback period, thereby preventing disturbance of the video signal.Therefore, the control signals F, m, n should be changed in the vertical flyback period. Is desirable.

FIG. 17 shows an embodiment of image blur suppression. In the figure, reference numeral 104 denotes a motion detection circuit. The motion detection circuit may detect the shake of the imaging device using the angular velocity sensor, or may detect the shake from the video signal. The motion detection circuit supplies a motion detection signal indicating the direction and how many pixels the image has moved to the scanning pixel area control circuit, and controls the scanning pixel area based on the detection signal.

FIG. 18 shows an embodiment in which the screen is scrolled. In the figure, reference numeral 105 denotes a counter circuit. The counter circuit supplies a control signal that gradually increases or decreases the value to the scanning pixel area control circuit, so that the image gradually moves up and down on the monitor screen, or scrolls moving left and right with a smooth movement. Can be realized.

〔The invention's effect〕

According to the present invention, while performing two-row simultaneous reading, the area of a pixel that performs normal transfer, that is, the scanning pixel area is set to one.
Since the image can be moved at the pixel pitch, smooth image movement can be realized.

[Brief description of the drawings]

FIG. 1 is a diagram showing an embodiment of the present invention, FIGS. 2 to 6 are diagrams showing a specific example of the structure and operation of the image pickup device of FIG. 1, and FIGS. 7 to 10 are diagrams of FIG. FIGS. 11 to 16 are diagrams for explaining the operation of FIG. 1, FIG. 17 is a diagram showing another embodiment, and FIGS. It is a figure which shows another Example. 100 image sensor 102 transfer pulse generation circuit 103
... A scanning pixel area control circuit.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-130673 (JP, A) JP-A-59-72876 (JP, A) JP-A-63-84275 (JP, A) JP-A-1- 125064 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04N 5/232 H04N 5/335

Claims (11)

(57) [Claims] An image sensor; a transfer pulse generating means for supplying a transfer pulse for reading a signal from the image sensor to the image sensor; and a control signal for controlling a scan pixel area and driving of the image sensor. Scanning pixel area control means for supplying to the pulse generation means, and in the first field, the 2Nth row and 2N + 1
In the second field, the second field of the image sensor is controlled such that the 2N + 1th row and the 2N + 2th row are mixed and read out, and when it is desired to change the scan pixel area, the first field In the second field, the (2M + 1) th row and the (2M + 2) th row of the image sensor are described.
The first driving for reading out by mixing 2M + 2 rows and the 2M + 3 rows, and the 2nd and 2M + 1 rows in the first field,
In the field of (2), by changing the drive of the image sensor by combining the second drive for reading out the 2M + 1 row and the 2M + 2 row in combination, the scanning pixel area of the image sensor is changed at a minimum of one pixel pitch. The imaging device according to claim 1, wherein: 2. An image pickup device, transfer pulse generating means for supplying a transfer pulse for reading a signal from the image pickup device to the image pickup device, and a control signal for controlling a scan pixel area and driving of the image pickup device. Scanning pixel area control means for supplying to the pulse generation means, wherein the transfer pulse generation means mixes two rows of signals of pixels adjacent to the image sensor vertically in an odd field when the control signal does not change. The transfer pulse for the odd field is read out in the even field, and the transfer pulse for the even field in the even field is read out by mixing pixel rows of a combination shifted by one row from the pixel row mixed and read by the transfer pulse for the odd field. When a certain change occurs in the control signal, a transfer pulse for the even field is supplied in an odd field, and the odd pulse is transmitted in an even field. A scan pulse area of the image sensor is changed at a minimum of one pixel pitch by generating a transfer pulse to read out a pixel row of a combination shifted by two rows from a pixel row mixed and read out by the transfer pulse for the field. An imaging device characterized by the above-mentioned. 3. An image pickup device, transfer pulse generating means for supplying a transfer pulse for reading a signal from the image pickup device to the image pickup device, and a control signal for controlling a scanning pixel area and driving of the image pickup device. Scanning pixel area control means for supplying to the pulse generation means, and in the first field, the scanning pixel area control means outputs a control signal for causing high-speed transfer to the 2N-1st row of the image sensor. Thereby, the transfer pulse generating means causes high-speed transfer up to the (2N-1) th row, performs normal transfer in which the 2N-th row and the (2N + 1) -th row of the image sensor are read out, and in the second field, the scan pixel By outputting a control signal for high-speed transfer up to the 2Nth row of the image sensor by the area control means, the transfer pulse generating means causes high-speed transfer up to the 2Nth row, and the 2N + 1th row of the image sensor. 2N
In the first field, when the scanning pixel area is changed, the pixel area control means controls the high-speed transmission up to the 2Nth row of the image sensor in the first field when the normal pixel data is read by mixing the +2 rows. By generating a signal, the transfer pulse generating means causes a high-speed transfer up to the 2Nth row, and performs a normal transfer in which the 2N + 1th row and the 2N + 2th row of the image sensor are read out in a mixed manner. In the second field, By generating a control signal for the pixel area control means to perform high-speed transfer up to the (2N + 1) th row of the image sensor,
An image pickup apparatus, wherein the transfer pulse generating means performs high-speed transfer up to the (2N + 1) th row, and performs a normal transfer for reading out the (2N + 2) th row and the (2N + 3) th row of the image sensor. 4. The transfer pulse generation means includes: a normal pulse generation means; a high-speed transfer pulse generation means; a normal transfer pulse output from the normal transfer pulse generation means; and a high-speed transfer pulse output from the high-speed transfer pulse generation means. The imaging apparatus according to claim 1, further comprising: a combining unit configured to combine the signals with the normal transfer pulse in a scanning pixel area. 5. The apparatus according to claim 1, further comprising a motion detecting means for detecting that the video signal has shaken, wherein said scanning pixel area control means changes a scanning pixel area in accordance with an output of said motion detecting means. Item 5. The imaging device according to any one of Items 1 to 4. 6. The apparatus according to claim 1, further comprising counter means for scrolling the image vertically and horizontally.
The imaging device according to any one of the above. 7. The imaging apparatus according to claim 1, wherein the change of the scanning pixel area or the switching cycle of the transfer pulse is a field cycle or a multiple of the field. 8. The imaging device according to claim 1, wherein the transfer pulse is switched within a vertical blanking period. 9. A method for controlling an image pickup apparatus having an image pickup device having a scanning pixel area which is an area smaller than an image pickup plane, wherein a second field of the image pickup element and a (2N + 1) th row of the image pickup element are provided in a first field.
In the second field, when the scanning pixel area is changed in a state where the driving of reading out the 2N + 1th row and the 2N + 2th row of the image pickup device in a mixed manner is performed, the image pickup device is used in the first field. 2M + 1 row and 2M
+2 rows, and in the second field, the 2M +
A first drive in which 2 rows and 2M + 3 rows are mixed and read, and a second drive in which a 2M row and 2M + 1 rows are mixed in the first field and a 2M + 1 row and 2M + 2 rows are mixed and read in the second field Changing the driving of the image pickup element in combination with the driving of the image pickup element to change the scanning pixel area of the image pickup element at a minimum of one pixel pitch. 10. A method for controlling an image pickup apparatus having an image pickup device having a scanning pixel area which is an area smaller than an image pickup plane, wherein in a first field, up to 2N-1 rows of the image pickup element are transferred at high speed. Then, the 2N-th row and the 2N + 1-th row of the image sensor are mixed and read, and in the second field, up to the 2N-th row of the image sensor is transferred at high speed, and the 2N + 1-th and 2N + 2 rows of the image sensor are read out. In the case where the scanning pixel area is changed in the state where the pixels are mixed and read, in the first field, high-speed transfer is performed up to the second M rows of the image sensor, and the second M + 1 rows and the second M + 2 rows of the image sensors are mixed. In the second field, high-speed transfer is performed up to the (2M + 1) th row of the image sensor, and the 2M +
In a first drive for performing a control of reading by mixing two rows and a 2M + 3 row, and in a first field, a first drive of the image sensor is performed.
High-speed transfer up to 2M + 1 rows, 2M rows + 2
And 2M + 3 rows are read out in a mixed manner, and in the second field, high-speed transfer is performed up to the 2M + 2 rows of the image sensor, and control is performed to mix and read out the 2M + 3 rows and the 2M + 4 rows of the image sensor. 2. A method for controlling an image pickup apparatus, comprising: changing a scanning pixel area of the image pickup element at a minimum of one pixel pitch by causing the image pickup element to be driven in combination with the second drive. 11. An image sensor, transfer pulse generating means for supplying a transfer pulse for reading a signal from the image sensor to the image sensor, and generating a control signal for controlling a scan pixel area of the image sensor by the transfer pulse generator. A scanning pixel area control unit that supplies a pixel to a pixel adjacent to the image sensor in an odd field in an odd field when the control signal does not change. An odd field transfer pulse that mixes and reads two rows of signals and an even field that mixes and reads pixel rows that are one row out of alignment with the pixel row that is mixed and read by the odd field transfer pulse in the even field When a certain change occurs in the control signal, a transfer pulse for the even field is generated in an odd field. In an even field, a transfer pulse is read out by mixing and reading out a pixel row of a combination shifted by two rows from a pixel row read and mixed by the transfer pulse for the odd field, so that the scanning pixel area of the image sensor is reduced by at least 1. A method for controlling an imaging device, wherein the method is changed at a pixel pitch.