JPH057347A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To lighten the burden of a CCD driver 6 accompanying the supply of a high-speed horizontal transfer pulse HHC by abbreviating drastically the supply of the high-speed horizontal transfer pulse HHC to transfer horizontally an unwanted charge at high speed. CONSTITUTION:The display area 62 of a CCD image sensor 1 is moved in an image pickup area 61 in accordance with a blurring quantity detected by a blurring detection circuit 5, and simultaneously, the unwanted charge in the area other than the display area 62 is controlled so that it is discharged to an unwanted charge discharge drain 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state image pickup device suitable for use in, for example, a video camera.

[0002]

2. Description of the Related Art Conventionally, there is known a solid-state image pickup device for picking up an image by using a solid-state image pickup device such as a CCD image sensor, which uses a memory to prevent a displayed image from being shaken due to camera shake. There is.

That is, such a solid-state image pickup device has a C
A memory having a storage area corresponding to the image pickup area of the CD image sensor is provided, and the image data obtained by the CCD image sensor is temporarily stored in the memory and the camera shake detection means detects the camera shake during image pickup. Then, the display area, which is an area for actually displaying an image, is moved in the memory according to the amount of camera shake detected by the camera shake detection means, and only the image data of the display area is read.

As a result, the image data of the display area can be read out following the camera shake, and the blurring of the display image due to the camera shake can be prevented.

[0005]

However, in the above-mentioned conventional solid-state image pickup device, since the above-mentioned memory must be provided, the circuit configuration becomes complicated.

Here, as a solid-state image pickup device for preventing the blurring of a display image due to camera shake without providing the memory, for example, as shown in FIG. 4A, a CCD image sensor 50 which is a solid-state image pickup element, An image pickup area 61 larger than the display area 62 for actually displaying an image is provided, the amount of camera shake is detected by the camera shake detection means, and the display area 62 is imaged as shown in FIG. 7B according to the detected camera shake amount. A thing that moves within the area 61 is conceivable.

As the CCD image sensor 50,
For example, a so-called interline transfer type as shown in FIG. 5 is provided.

In FIG. 5, an interline transfer type CCD image sensor 50 has a photodiode 70 for accumulating the received image pickup light as an electric charge, and a read gate 71 which is a transfer path of the electric charge read from the photodiode 70. , A vertical transfer path 72 for vertically transferring the charges, a horizontal transfer path 73 for horizontally transferring the charges, and a data detection section 74 for detecting and amplifying the charges horizontally transferred from the horizontal transfer path 73. ing.

In the solid-state image pickup device having such a CCD image sensor 50, when the image pickup is started, the handshake detecting means detects the handshake amount during the image pickup. This camera shake detection data is supplied to the solid-state image sensor driving means.

The solid-state image pickup device driving means determines the display area 62 according to the supplied camera shake detection data.

In the solid-state image pickup device driving means, a read pulse for reading the electric charge accumulated in the photodiode 70, and the read electric charge is sent to the horizontal transfer path 73 at a normal speed (normal frequency). Normal vertical transfer pulse for vertical transfer, high-speed vertical transfer pulse for vertically transferring the read charges to the horizontal transfer path 73 at high speed, and horizontal transfer of charges vertically transferred to the horizontal transfer path 73 at normal speed. A normal horizontal transfer pulse, a high-speed horizontal transfer pulse for horizontally transferring charges vertically transferred to the horizontal transfer path 73 at a high speed, and a switch pulse for ON / OFF controlling a switch 77 described later are supplied.

Here, for example, as shown in FIG.
It is assumed that the approximate center of the imaging area 61 is determined as the display area 62.

The CCD image sensor 50 has, for example, a vertical blanking period TVBLK3 shown in FIG. 6 (d).
A read pulse as shown in FIG. 7C is supplied at a time t51 approximately midway between (time t50 and time t52).

The CCD image sensor 50 transfers the charge accumulated in the photodiode 70 to the vertical transfer path 72 via the read gate 71 by the read pulse supplied.

Next, the solid-state image pickup device driving means, during the high-speed transfer period TVH2 which is from the time t51 at which the read pulse is supplied to the time t52 at which the vertical blanking period TVBLK3 ends, as shown in FIG. The high-speed vertical transfer pulse and the high-speed horizontal transfer pulse (not shown) are supplied to the CCD image sensor 50.

The charges transferred to the vertical transfer path 72 are transferred at high speed vertically to the horizontal transfer path 73 by the high speed vertical transfer pulse, and the charges transferred at high speed vertically to the horizontal transfer path 73 are transferred at high speed by the high speed horizontal transfer pulse. It is transferred horizontally.

The solid-state image pickup device driving means has the display area 6 shown in FIG. 4 in the high-speed transfer period TVH2.
The respective high-speed transfer pulses are supplied to the CCD image sensor 50 so that all the charges in the unnecessary charge region 63 under 2 are transferred at high speed.

However, if unnecessary charges other than the charges in the display area 62 are output, it is not preferable in the subsequent data processing.

Therefore, the solid-state image pickup device driving means is
During the high-speed transfer period TVH2, a high level switch pulse as shown in FIG. 6A is supplied to the input terminal 7 shown in FIG.
6 to the switch 77.

The switch 77 is normally supplied with a low level switch pulse and turned off, but is turned on when supplied with the high level switch pulse.

As a result, the unnecessary charges in the unnecessary charge region 63 that are transferred at high speed are grounded via the resistor 78 and are not output.

Next, the solid-state image pickup device driving means is shown in FIG.
In the vertical video period TVVK2 (time t52 to time t53) shown in (d), the normal vertical transfer pulse as shown in FIG.
It is supplied to the D image sensor 50, and the charges in the display area 62 are normally transferred.

The unnecessary charges in the unnecessary charge regions 65 and 66 before and after the display region 62 are transferred at high speed during a horizontal blanking period, which will be described later.

The charges in the display area 62 that are normally transferred during the vertical video period TVVK2 are detected and amplified by the data detection section 74 shown in FIG. 5, and are output to the outside through the output terminal 75.

Next, the solid-state image pickup device driving means is shown in FIG.
Next vertical blanking period TVBLK4 shown in (d)
Since (time t53 to time t55) is started, a time t54 approximately in the middle of the vertical blanking period TVBLK4.
In order to transfer the unnecessary charges in the unnecessary charge region 64 above the display region 62 at a high speed during the high-speed transfer period TVH3 until the next read pulse is supplied to the high-speed transfer period shown in FIG. A vertical transfer pulse and a high-speed horizontal transfer pulse (not shown) are supplied to the CCD image sensor 50.

As a result, the unnecessary charges in the unnecessary charge region 64 above the display region 62 are transferred at high speed, and each charge in the unnecessary charge region 64 transferred at high speed is also switched by the switch pulse shown in FIG. 6A. As a result, the switch 77 is turned on and no output is made.

As described above, the solid-state image pickup device driving means performs high-speed transfer of unnecessary charges in the unnecessary charge regions 65 and 66 before and after the display region 62 within the horizontal blanking period.

That is, the solid-state image pickup device driving means is
Horizontal blanking period THBLK3 shown in FIG.
The high speed from the time when the vertical transfer pulse as shown in FIG. 7B is supplied to the time t62 at which the horizontal blanking period THBLK3 ends, at a time t61 which is approximately midway between (time t60 and time t62). In the transfer period THH3, a high-speed horizontal transfer pulse as shown in FIG. 7C is supplied to the CCD image sensor 50 in order to transfer the unnecessary charges in the unnecessary charge region 65 in front of the display region 62 at high speed.

As a result, the unnecessary charges in the unnecessary charge region 65 are transferred at high speed within the high-speed transfer period THH3. The unnecessary charges in the unnecessary charge region 65 transferred at high speed are also shown in FIG. 7A. As described above, the switch 77 is turned on by the switch pulse supplied during the horizontal blanking period and is not output.

Next, the solid-state image pickup device driving means is shown in FIG.
During the horizontal video period THVK2 (time t62 to time t63) shown in (d), the charges in the display area 62 are normally transferred at the normal speed (normal frequency).

The charges of the display area 62 which are normally transferred are output to the output terminal 75 via the data detecting section 74 shown in FIG.
Output to the outside.

Next, the solid-state image pickup device driving means is shown in FIG.
Next horizontal blanking period THBLK4 shown in (d)
From time t63 when (time t63 to time t65) is started to time t64 approximately midway of the horizontal blanking period THBLK4 until the next vertical transfer pulse shown in FIG. During a certain high-speed transfer period THH4, a high-speed horizontal transfer pulse as shown in FIG. 6C is supplied to the CCD image sensor 50 in order to transfer the unnecessary charges in the unnecessary charge region 66 behind the display region 62 at high speed.

As a result, unnecessary charges in the unnecessary charge region 66 are transferred at high speed within the high-speed transfer period THH4. The unnecessary charges in the unnecessary charge region 65 transferred at high speed are also shown in FIG. 7A. The switch 77 is turned on by the switch pulse and is not output.

The display area 6 is displayed in accordance with the detected camera shake amount.
The solid-state imaging device that moves 2 moves out only the charges accumulated in the display area 62 in this way.

However, in such a solid-state image pickup device, the unnecessary charges other than the charges in the display area 62 are within a high-speed transfer period which is about half the period of each blanking period because of the convenience of data processing later. Have to transfer at high speed.

Therefore, the unnecessary charges are transferred at high speed,
A great burden is placed on the pulse driver that supplies the high-speed vertical transfer pulse and the high-speed horizontal transfer pulse.

Since the unnecessary charges must be transferred at a high speed within a limited period of time, which is the high-speed transfer period, for example, the unnecessary charges in the horizontal transfer path 73 are not completely transferred at a high speed before the above-mentioned unnecessary charges are transferred. Charges in the display area 62 are vertically transferred to the horizontal transfer path 73, and unnecessary charges and charges in the display area 62 are mixed and output on the horizontal transfer path 73. High-speed horizontal transfer may not catch up.

When the transfer efficiency is deteriorated in this way, the mixed charges on the horizontal transfer path 73 are output as they are, which may cause color unevenness in the display image.

Further, when the transfer of the charges in the display area 62 is completed, the remaining charges are unnecessary, and the development of a solid-state image pickup device capable of omitting the high-speed transfer of the remaining charges is desired. There is.

The present invention has been made in view of the above-mentioned problems, and a solid-state image pickup capable of improving the transfer efficiency by omitting high-speed transfer of unnecessary charges remaining after the charges in the display area are transferred. The purpose is to provide a device.

[0041]

According to the present invention, an imaging area larger than a display area for displaying an image, a transfer register for transferring charges accumulated in the imaging area, and a charge transferred to the transfer register are provided. A solid-state imaging device provided with a charge discharging unit for discharging, a camera shake detecting unit for detecting a camera shake amount generated during imaging, and the transfer register and the charge discharging unit according to the camera shake amount detected by the camera shake detecting unit. Drive means for supplying a drive pulse for driving the control circuit, the drive means controlling the transfer register so that the charge accumulated in the display area is transferred and output to the outside, and the drive means other than the display area. The above-mentioned problem is solved by controlling the charge discharging unit so that the charges accumulated in the discharge unit are discharged.

[0042]

In the solid-state image pickup device according to the present invention, the solid-state image pickup device is provided with the electric charge discharging section, and the electric charge is discharged so that the electric charge accumulated in the area other than the display area is discharged in accordance with the shake detected by the shake detecting means. By controlling the unit, it is possible to allow a high-speed transfer of unnecessary charges with a margin and improve the transfer efficiency.

[0043]

Embodiments of the solid-state image pickup device according to the present invention will be described below with reference to the drawings.

The solid-state image pickup device according to the present invention is shown in FIG.
As shown in FIG. 4, a CCD image sensor 1 which is a solid-state image sensor, a camera-shake detection circuit 5 which is a camera-shake detecting unit for detecting the amount of camera-shake generated during imaging, and a timing for generating drive pulses and the like for driving the solid-state image sensor. Generator 7
And a CCD driver 6 which is a pulse driver and is a driving means for driving the CCD image sensor 1 and the like in response to a driving pulse and the like from the timing generator 7.

The CCD image sensor 1 shown in FIG.
As shown in (a) and (b), the image pickup area 61 is larger than the display area 62 for actually displaying the image. A so-called interline transfer type shown in FIG. 5 is used.

The horizontal transfer path 2 of the CCD image sensor 1 which is a transfer register for transferring the charges accumulated in the image pickup area 61 is continuously provided with an unnecessary charge discharging gate 3 and is unnecessary. The charge discharging gate 3 is provided with an unnecessary charge discharging drain 4 which is a charge discharging portion for discharging the charges transferred to the horizontal transfer path 2 continuously.

The timing generator 7 has the C
A read pulse VT for transferring the charges accumulated in the photodiode of the CD image sensor 1 to the vertical transfer path, a switch pulse SP for controlling ON / OFF of a switch 9 described later, and a high speed vertical transfer of the charges read by the read pulse VT. High-speed vertical transfer pulse VHC, normal vertical transfer pulse VLC for vertically transferring charges read by the read pulse VT at normal speed (frequency), high-speed horizontal transfer of charges vertically transferred to the horizontal transfer path 2 The horizontal transfer pulse HHC, the normal horizontal transfer pulse HLC for transferring the charges vertically transferred to the horizontal transfer path 2 at a normal speed, and the drain pulse SG for controlling the ON / OFF of the unnecessary charge discharging gate 3 are generated, Each of these pulses is supplied to the CCD driver 6.

Next, a concrete operation will be described. First, when image pickup is started, the camera shake detection circuit 5 detects the amount of camera shake during image pickup, and supplies this camera shake detection data to the CCD driver 6.

The CCD driver 6 determines the display area 62 according to the supplied camera shake detection data.

Here, for example, it is assumed that the approximate center of the image pickup area 61 shown in FIG. 4A is determined as the display area 62.

The CCD image sensor 1 has, for example, a vertical blanking period TVBLK1 shown in FIG.
At a time t2 approximately midway between (time t1 to time t3), the read pulse VT as shown in FIG.

The CCD image sensor 1 transfers the charge accumulated in each photodiode to the vertical transfer path via the read gate by the read pulse VT supplied.

Next, the CCD driver 6 displays the display area 62 in the unnecessary charge discharging period TFD1 which is from the time t2 when the read pulse VT is supplied to the time t3 when the vertical blanking period TVBLK1 ends.
In order to perform high-speed vertical transfer of the unnecessary charges in the unnecessary charge region 63 below, a high-speed vertical transfer pulse VHC as shown in FIG.
Is supplied to the CCD image sensor 1, and every time the high-speed vertical transfer pulse VHC is supplied, a drain pulse SG as shown in FIG.

Each of the charges transferred to the vertical transfer path is transferred to the horizontal transfer path 2 at high speed vertically by the supplied high speed vertical transfer pulse VHC.

Here, the unnecessary charge discharging gate 3 is normally in a non-conductive state, but becomes conductive when the drain pulse SG is supplied.

When the drain pulse SG is supplied and the unnecessary charge discharging gate 3 becomes conductive, all the charges existing in the horizontal transfer path 2 are discharged to the unnecessary charge discharging drain 4.

Therefore, all the unnecessary charges in the unnecessary charge regions 63 which are vertically transferred at high speed to the horizontal transfer path 2 are discharged to the unnecessary charge discharging drain 4 and are not output.

By discharging the unnecessary charges in the unnecessary charge region 63 to the unnecessary charge discharging drain 4 in this manner, each unnecessary charge of the unnecessary charges 63 transferred at high speed to the horizontal transfer path 2 at high speed is discharged. Since it is not necessary to perform horizontal transfer and it is not necessary to supply the high-speed horizontal transfer pulse HHC, it is possible to reduce the load on the CCD driver 6 which is a pulse driver.

Next, the CCD driver 6 is operated as shown in FIG.
In the vertical video period TVVK1 (time t3 to time t4) shown in (d), the normal vertical transfer pulse VLC having the normal speed (normal frequency) and the normal horizontal transfer pulse HLC (not shown) as shown in FIG. The charge in the display area 62 is supplied to the CCD image sensor 1 and transferred normally.

The unnecessary charges in the unnecessary charge regions 65 and 66 before and after the display region 62 are transferred at high speed during the horizontal blanking period described later.

The charges in the display area 62 which are normally transferred during the vertical video period TVVK1 are detected and amplified by the data detection section 8 shown in FIG. 1 and output to the outside through the output terminal 11.

Next, the CCD driver 6 is operated as shown in FIG.
Next vertical blanking period TVBLK2 shown in (d)
In the unnecessary charge discharging period TFD2, which is a period from the start of (time t4 to time t6) to the time when the next read pulse VT is supplied at a time t5 approximately in the middle of the vertical blanking period TVBLK2, the above display is performed. In order to transfer the unnecessary charges in the unnecessary charge area 64 above the area 62 at high speed, a high-speed vertical transfer pulse VHC as shown in FIG.
Each time the high-speed vertical transfer pulse VHC is supplied to the image sensor 1, the drain pulse SG shown in FIG.

As a result, the unnecessary charge discharging gate is rendered conductive, and all the unnecessary charges in the unnecessary charge region 64 transferred at high speed vertically to the horizontal transfer path 2 are discharged to the unnecessary charge discharging drain 4.

Therefore, also in this case, it is not necessary to supply the high-speed horizontal transfer pulse HHC, and the load on the CCD driver 6 due to the supply of the high-speed horizontal transfer pulse HHC can be reduced.

As described above, the CCD driver 6 transfers the unnecessary charges in the unnecessary charge regions 65 and 66 before and after the display region 62 at high speed within the horizontal blanking period.

That is, the CCD driver 6 shown in FIG.
After the normal vertical transfer pulse VLC as shown in FIG. 7C is supplied at a time t11 approximately in the middle of the horizontal blanking period THBLK1 (time t10 to time t12) shown in FIG. High-speed transfer period THH1 which is until time t62 when the period THBLK1 ends
In order to transfer all the charges in the unnecessary charge area 65 in front of the display area 62 at high speed, a high-speed horizontal transfer pulse HHC as shown in FIG.
And the switch pulse SP as shown in FIG. 9B is supplied to the switch 9 while the high-speed horizontal transfer pulse HHC is supplied during the high-speed transfer period THH1.

The switch 9 is normally supplied with the low level switch pulse SP and is in the off state, but is supplied with the high level switch pulse SP and is in the on state.

As a result, the unnecessary charges in the unnecessary charge region 65 transferred at high speed within the high speed transfer period THH1 are:
It is grounded via the resistor 10 and is not output.

Next, the CCD driver 6 operates as shown in FIG.
Horizontal video period THVK1 (time t12 to time t1
In 3), the charges in the display area 62 are normally transferred at the normal speed.

The charges of the display area 62 that are normally transferred are output from the output terminal 11 to the outside through the data detection section 8.

Next, the CCD driver 6 causes the next horizontal blanking period THBLK2 (time t13-) shown in FIG.
At the time t15 approximately midway of the horizontal blanking period THBLK2 from the start of the time t16), the time t15 in FIG.
At time t14 immediately after the unnecessary charge discharging period TFD3, which is the period until the next normal vertical transfer pulse VLC is supplied, is discharged, the unnecessary charges in the unnecessary charge region 66 behind the display region 62 are discharged. Therefore, the drain pulse SG as shown in FIG. 9A is supplied to the unnecessary charge discharging gate 3.

As a result, all the unnecessary charges 66 are discharged to the unnecessary charge discharging drain 4.

Therefore, the unnecessary charge discharging period TFD3
Shows the high-speed horizontal transfer pulse HH as shown in FIG.
It is not necessary to supply C, and the above C which is a pulse driver
The load on the CD driver 6 can be reduced.

Further, since the high-speed horizontal transfer can be omitted, a time margin corresponding to the unnecessary charge discharging period TFD3 can be provided, and a time margin can also be provided for the supply of the next vertical transfer pulse. The charge transfer efficiency can be improved.

Since the charge transfer efficiency can be improved, it is possible to prevent color unevenness of the display image due to the deterioration of the charge transfer efficiency.

As is clear from the above description, the solid-state image pickup device according to the present invention controls the unnecessary charge discharging gate 3 to be in the conductive state when the unnecessary charges other than the display area 62 are transferred at high speed. By doing so, the unnecessary charges that have been vertically transferred at high speed to the horizontal transfer path 2 can be discharged to the unnecessary charge discharging drain 4, so that it is not necessary to supply the high-speed horizontal transfer pulse HHC for transferring the unnecessary charges at high speed. The load on the CCD driver 6 associated with the supply of the high-speed horizontal transfer pulse HHC can be greatly reduced.

Therefore, a margin for the time for supplying the high-speed horizontal transfer pulse HHC can be provided, and data processing can be performed with this time margin, so that color unevenness or the like of the display image due to deterioration of charge transfer efficiency occurs. Can be prevented.

[0078]

According to the solid-state image pickup device of the present invention, the solid-state image pickup device is provided with a charge discharging portion, and the charge discharging portion is accumulated in a region other than the display area determined according to the shake detected by the shake detecting means. By discharging the unnecessary charges which are the accumulated charges, the supply of the high-speed transfer pulse for transferring the unnecessary charges at a high speed can be largely omitted, and the load accompanying the high-speed transfer pulse supply of the driving means can be reduced. . Further, since the supply of the high-speed transfer pulse is omitted, a time margin can be provided, so that the charge can be transferred with a margin, and color unevenness or the like of the display image due to deterioration of the charge transfer efficiency can be prevented. be able to.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of a solid-state imaging device according to the present invention.

FIG. 2 is a time chart for explaining discharge of unnecessary charges in the vertical blanking period of the solid-state imaging device according to the present invention.

FIG. 3 is a time chart for explaining discharge of unnecessary charges in a horizontal blanking period of the solid-state imaging device according to the present invention.

FIG. 4 is a diagram illustrating movement of a display area according to the amount of camera shake in a solid-state imaging device that prevents the display image from being shaken due to camera shake by moving the display area in the CCD image sensor according to the amount of camera shake detected. It is a schematic diagram for explaining.

FIG. 5 is a schematic diagram for explaining an interline transfer type CCD image sensor.

FIG. 6 is a time chart for explaining charge transfer and the like in a vertical blanking period of a solid-state imaging device that moves a display area according to the amount of camera shake.

FIG. 7 is a time chart for explaining charge transfer and the like in a horizontal blanking period in a solid-state imaging device that moves a display area according to the amount of camera shake.

[Explanation of symbols]

 1 CCD image sensor 2 Horizontal transfer path 3 Unwanted charge discharge gate 4・ ・ ・ ・ Unnecessary charge discharging drain 5 ・ ・ ・ ・ ・ ・ Camera shake detection circuit 6 ・ ・ ・ ・ ・ ・ CCD driver 7 ・ ・ ・ ・ ・ ・ Timing generator 8 ・・ ・ ・ ・ ・ ・ ・ Data detector 9 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Switch 10 ・ ・ ・ ・ ・ ・ ・ ・ ・ Resistance

Front page continued (72) Inventor Maki Sato 6-735 Kitashinagawa, Shinagawa-ku, Tokyo

Claims (1)

Claim: What is claimed is: 1. An imaging area larger than a display area for displaying an image, a transfer register for transferring charges accumulated in the imaging area, and discharging the charges transferred to the transfer register. A solid-state imaging device provided with a charge discharging unit, a shake detecting unit for detecting a shake amount generated during imaging, and driving the transfer register and the charge discharging unit according to the shake amount detected by the shake detecting unit. Driving means for supplying a driving pulse for controlling the transfer register so that the electric charge accumulated in the display area is transferred and output to the outside, and the electric charge is accumulated in areas other than the display area. A solid-state imaging device, wherein the charge discharging unit is controlled so that the generated charges are discharged.