JP2956655B2 - Video camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION The present invention relates to a charge coupled device (CCD: Ch).
defects included in solid-state image sensors such as (arge Coupled Device)
Deterioration of image quality due to imaging output from pixels
The present invention relates to a video camera having a function of correcting an error. [0002] 2. Description of the Related Art Generally, semiconductor devices such as CCDs are used.
In solid-state image sensors, local crystal defects
Constant bias voltage to the imaging output according to the amount of incident light.
This causes a defective pixel to be added to the pressure,
Is known to cause image quality degradation due to their imaging output.
ing. A constant bias voltage is always added to the above imaging output
In the case of image defects, the image defect signal is
Once processed, it appears as a bright spot on the monitor screen.
This is called a white defect. Conventionally, solid-state imaging devices such as those described above
Signal that the image quality has deteriorated due to the imaging output from defective pixels
To correct by processing, for example,
Information indicating the presence or absence of a defect for each pixel is stored in a memory.
Image from the defective pixel based on the information in the memory
Obtained from the pixel next to the defective pixel instead of the output
Interpolation was performed using the imaging output. Note that this
The information indicating the presence or absence of a defect for each pixel of the solid-state
When stored in memory, the total number of pixels of the solid-state imaging device
Must use a huge amount of memory equivalent to
Since there is no defect, the applicant of the present application sequentially records the presence or absence of a defect for each pixel.
Instead of remembering, defective pixels included in the solid-state imaging device
The distance between defective pixels as data indicating the position of
And reduce the storage capacity by storing in memory
We have already proposed such technology (Japanese Patent Publication No. 60-34).
No. 872). [0004] Conventionally, correction processing by the interpolation has been described.
In this case, the imaging output obtained from the pixels near the defective pixel
If there is no function, a large correction error will occur.
Position of defective pixel included in image sensor and its output signal
Data on the level of defective components contained in the memory
And store it based on the data read from the memory.
Then, the defective image among the output signals of the solid-state imaging device is
The defect correction signal is formed at the timing of the
Addition to the output signal of the solid-state image sensor
Image defect correction device for solid-state imaging device
Has been proposed (see JP-A-60-513780).
Teru. ). Further, in general, a solid-state imaging device is used.
Solid-state imaging device having an imaging unit
Field readout to read out signal charges from all pixels
Signal charge from all pixels in one mode or one frame period
In the frame read mode for reading,
The imaging output is obtained from the child. In addition,
Control the effective charge accumulation period of the solid-state imaging device.
The electronic shutter function replaces the mechanical shutter mechanism.
Is added. Still further, a solid color for performing color imaging
In an imaging device, three solid-state imaging devices
The image pickup unit is constructed as follows, and the three primary color components of red (R), green (G),
The three primary colors that are imaged by the imaging light separated into minutes
Color video based on the imaging output of the subject image
A signal is formed. And conventionally,
In this way, the subject image of each color component obtained by color separation of the imaging light is duplicated.
Solid-state imaging device for imaging by an imaging unit composed of
To improve the horizontal resolution in color imagers.
As a method, one solid-state image sensor, for example, green (G)
The solid-state image sensor that captures the color component object image is
A solid that captures each subject image of the (R) color component and the blue (B) color component
1/2 picture element pitch shifted in the horizontal direction with respect to the image sensor
A so-called space picture element shifting method that is arranged at a position is proposed
Have been. [0007] By the way, in semiconductors
In the formed solid-state image sensor, false signal power caused by dark current
The signal level due to the load is large,
Although image defects are relatively prominent, the dark current
Image defects were observed while minimizing the occurrence of image defects.
Of course, the conventionally known temperature-dependent white defect image
In addition to the element, constant bias to the imaging output according to the amount of incident light
Temperature-independent black defect pixel from which charge is subtracted
And white flaws that do not depend on temperature but depend on the amount of incident light
Defects and black defect defects appear as image defects in the image output.
It turned out. Further, a solid-state imaging device having an electronic shutter function has been added.
In an imaging device, the charge of the solid-state imaging device that constitutes the imaging unit is
Variable storage time according to the set speed of the electronic shutter
Is included in the imaging output from defective pixels
The defect level due to defective pixels
Changes in usage information, such as switching the read mode of
However, the defect level changes. [0009] Accordingly, an object of the present invention is to provide a conventional
Due to changes in shutter speed.
Image defects due to white or black defects that change the defect level
The image quality can be corrected appropriately and the image quality is extremely good.
To provide a video camera capable of obtaining an image output signal
It is in. [0011] SUMMARY OF THE INVENTION The present invention provides a solid-state imaging device.
A video camera having a solid-state imaging device.
Of defective pixels and the defects contained in the output signal
Storage means for storing data on the component level;
The data read from the storage means is initialized.
Control based on shutter speed data
By the above, the above-mentioned solid according to the above-mentioned shutter speed
Defect correction signal generation means for generating a defect correction signal for an image sensor
And a solid-state imaging device based on the defect correction signal.
Defect correction means for performing defect correction on the output signal of
It is characterized by That is, in the video camera according to the present invention,
Is the position of the defective pixel included in the solid-state imaging device and its position.
Data on the level of defect components contained in the output signal
Initialized with the data read from the stored storage means
Correction signal based on current shutter speed data.
Signal generation means to generate a defect correction signal for the solid-state imaging device.
Output signal of the solid-state imaging device by the defect correction means.
Perform defect correction on the signal. [0013] BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described in detail with reference to the drawings. The present invention is shown, for example, in the block diagram of FIG.
It is applied to a color video camera having such a configuration. this
In the color video camera, the imaging light is red by the imaging optical system 1.
(R), green (G), and blue (B)
Empty with three solid-state image sensors focused on the imaging surface
Three-plate type imaging unit 2 configured by adopting the inter-pixel displacement method
Performs color imaging. In this color video camera,
As a solid-state image sensor constituting the image unit 2, for example,
For example, as shown in FIG.
A large number of light receiving sections S corresponding to pixels, and one of the light receiving sections S
Transfer register VR provided along the vertical direction on the side
Provided on each end side of each vertical transfer register section VR.
It consists of a horizontal transfer register section HR and is obtained by each light receiving section S.
Signal charge corresponding to the amount of received light per field period
Or for each vertical line every frame period
To each of the vertical transfer registers VR,
The signal charges are transferred to the horizontal transfer register through the transfer register section VR.
To the horizontal transfer register HR.
Extract signal charge for each horizontal line as image output
Three interline transfer type CCDs
The image sensors 2R, 2G, 2B are used. Soshi
Then, as shown in FIG. 3, the imaging unit 2
The three CCD image sensors 2R,
Captures the subject image of the green (G) color component of 2G and 2B
CCD image sensor 2G is used for other red (R) color components and blue (B)
Each CCD image sensor that captures each subject image of color components
1/2 picture element pitch (P / 2) in the horizontal direction for 2R, 2B
It is located at a shifted position. The driving circuit 3 of the image pickup section 2 has a configuration shown in FIG.
Sync signal SYN provided by sync generator 4
Vertical transfer pulse φ synchronized with C_VAnd horizontal transfer pulse φ_H
Is supplied from the timing generator 5 and
The light receiving of each of the CCD image sensors 2R, 2G, 2B
The signal charge corresponding to the amount of received light obtained in the section S is one field.
Field read mode, which reads all data during
The signal charges obtained in each light receiving section S are all
To specify the frame read mode to read
The mode designation signal and the CCD image sensor 2R,
A so-called electronic shutter by controlling the charge accumulation time of 2G and 2B
Shutter control signals for controlling the speed of
Controller 6. Here, the CCD I constituting the imaging unit 2
Image sensors 2R, 2G, and 2B store 1/30 seconds of charge
Charge accumulation for frame read mode with time
In the field readout mode where the time is 1/60 second,
Load accumulation amount becomes half of the frame readout mode
Therefore, it can be obtained by two light receiving units S adjacent in the vertical direction.
By reading by adding signal charges, the frame reading
The sensitivity is the same as that of the protruding mode. The three CCD image sensors 2R, 2
R, G, and B channels obtained by the imaging unit 2 composed of G and 2B.
Channel color image output (S_R), (S_G), (S_B) Indicates preamplification
From the processor 7 to the signal processing system 9 via the correction signal adding circuit 8.
The correction signal adding circuit 8 performs defect correction processing.
After that, the signal processing system 9 performs gamma correction and shading.
Processing is performed along with
R (International Radio Communications Advisory Committee) and EIA (American Electronics
Industry standard) standardized standard television system
Matching video signal (S_OUT) And output. In this color video camera,
For CCD image sensors 2R, 2G, 2B,
Analyzes the location of defective pixels, defect types and defect levels
These data are used as correction data
The correction signal generation circuit 11
Based on the correction data read from the memory 10
And defective images of the CCD image sensors 2R, 2G, 2B.
The white defect correction signal (W_CP),
Black defect correction signal (B_CP), White shading correction signal (W
_SH) Or black shading correction signal (B_SH) Etc.
These correction signals (W_CP), (B_CP), (W_SH), (B_SH) The correction signal
The correction signal addition circuit 8 and the signal
Supply to the signal processing system 9, the correction signal addition circuit
The image defect is corrected by the path 8 and the signal processing system 9.
Has become. Further, a temperature sensor 13 is provided in the image pickup section 2.
And the CCD image sensors 2R, 2G, 2
The temperature of B is detected, and the defect level has a temperature dependence on white.
Each correction signal (W_CP), (B
_SH) Is based on the output detected by the temperature sensor 12
Temperature correction processing is performed by the temperature correction circuits 14 and 15, respectively.
I am doing it. Further, the detection by the temperature sensor 13 is performed.
The CCD image sensors 2R, 2 indicated by the output
The temperature of G and 2B is analog-digital (A / D) converter 1
The above-mentioned memory which is digitized in 6 and becomes address data
10 are provided. The CCD image sensors 2R, 2G, 2B
Is higher than normal temperature where image defects are likely to appear.
It is performed at a low test temperature. In the above defect test, for example,
As shown in FIG. 4, the CCD image sensors 2R, 2R
G, 2B Each position A of white defect pixel, black defect pixel, etc.₁,
A_Two.., And the type and level of the defect
₁, l_Two... and the position data of each defective pixel
Data is obtained as follows. That is, the criteria
Point A₀First defective pixel position A counting from₁Is the above reference point
A₀Distance d from₁Is encoded into a predetermined bit of digital
Data, and other defective pixel positions A_n(n is arbitrary
Is the previous defective pixel position A_n-1Distance from
d_nAre encoded into digital data of a predetermined bit.
And the relative distance in the example of FIG.
1 defective pixel position A₁And the second defective pixel position A_TwoBetween
Dummy defective pixel position A_DM1Any defective paintings, like
The relative distance from the element to the next defective pixel is too large
When cannot be represented by constant bit digital data
Set a dummy defective pixel between those defective pixels.
Then, the relative distance d is set to the first defective pixel position A.₁From Dami
-Defective pixel position A_DM1Distance d to_TwoAnd the lack of the dummy
Pixel position A_DM1From the second defective pixel position A_TwoDistance to
Separation d_ThreeAnd the digital
Express as data. Here, the CCD image sensor 2R,
Position A of defective pixel of 2G, 2B₁, A_Two... is two-dimensional
Expressed as a pair address, for example, 10 bits in the horizontal direction
Address, 10 bits in the vertical direction, a total of 20 bits of address data
Data, but as described above, the defective pixel position A_n(n
Is an arbitrary integer) to the previous defective pixel position A_n-1From
Distance d_nEach of which is encoded into a predetermined bit of digital
By adopting relative addresses represented by data,
The number of bits needed to represent the maximum value of the relative address.
Dress data can be compressed, for example, 12 bits
Address of one defective pixel as relative address data of
This results in 8-bit data compression. Also, a 12-bit
The relative distance that can be represented by relative address data is
For example, assuming a maximum of 4.5 lines, a certain defective pixel position A_n
From the next defective pixel position A_{n + 1}Relative distance d to_nIs 4.
If the distance is more than 5 lines, the relative distance d_nTo
The defective pixels are divided so as to be within 4.5 lines.
Position A_n, A_{n + 1}One or more dummy defects in between
Pixel position A_DMTo set the 12-bit relative
Defective pixel position A by address data_{n + 1}Can represent
Wear. Thus, any defective pixel position A_nNext missing from
Pixel position A_{n + 1}Relative distance d to_nIs too big above
A field that cannot be represented by the specified bit of digital data
In this case, set a dummy defective pixel between those defective pixels.
Relative distance d_nBy dividing all defective pixels
The position can be represented by digital data of predetermined bits.
Become so. The dummy defective pixel position A_DM1
Are read from the CCD image sensors 2R, 2G, 2B.
Within the blanking period BLK of the imaging output signal
Setting has an adverse effect on the quality of the imaging output signal
Is not exerted. In this color video camera,
As shown in the memory map of FIG.
Field read area A from address to address 4095
RFD and frames from addresses 4096 to 8191
Read area ARFM, and further read each area
ARFD, ARFM are the minimum correction amplitude data area respectively.
ARSA, correction data area ArcM, shutter speed
It is divided into data areas ARSS and used. In the minimum correction amplitude data area ARSA,
Is an image pickup by the CCD image sensors 2R, 2G, 2B.
Imaging conditions such as temperature and shutter speed for output
N minimum correction amplitudes to be corrected according to
Minimum correction amplitude data (DSA) is written. Above
The small correction amplitude data (DSA) is the minimum of each RGB channel.
4 bits each for the corrected amplitude data (DSAR), (DSAG), and (DSAB)
Use 2 bits for cycle time data,
Consists of 2 bytes of data with 2 bits of unused
Have been. In the correction data area ARCM,
Above about CCD image sensor 2R, 2G, 2B
The correction data (DCM) obtained by performing the defect test
Is embedded. The above correction data (DCM) is the defect level
8-bit amplitude data (DCMA) according to the data, indicating the type of defect
2 bit mode select data (DMS), correction channel
2-bit color code data (DCC) indicating the channel
12-bit relative address indicating the distance to the defective pixel position
Consists of 3 bytes of data (RADR)
ing. The correction data (DCM) contains the dummy
The correction data (DCM ') for the defective pixel is also included. Further, the shutter speed data area
ARSS contains the set shutter speed of the electronic shutter.
The 4-bit shutter speed data shown
Shutter data (SHD) to be converted to
12 bits indicating the start address of area ARCM, that is, 2N address
2 bytes consisting of the first address data (FADR)
15 write data are written. In this color video camera,
The positive signal generation circuit 11 has a specific example together with its peripheral circuits.
As shown in FIG.
Latch circuits 21 and 2 to which various data to be supplied are supplied.
2,23,24,25,26,27 and strobe generation circuit 2
8 is provided. The correction signal generation circuit 11 includes the system
Imaging operation in the operation mode set in the
When performing this, one field or one frame
Perform the initial setting operation during the
Imaging operation such as the shutter speed set for the controller 6
Operating condition and A / D converter 1 from temperature sensor 13
Memory according to the temperature data given via
Read from 10 minimum corrected amplitude data area ARSA
Minimum corrected amplitude data (DSAR) for each RGB channel
AG), (DSAB) to the first to third latch circuits 21, 22, 2
3 and the shutter of the memory 10
Shutter data read from the speed data area ARSS
(SHD) is latched in the fourth latch circuit 24, and
Next, read from the above shutter speed data area ARSS.
Based on the first address data (FADR)
The strobe generating circuit 28 uses the address counter 40
The head of the correction data area ARCM of the memory 10
Correction data (DCM) from address 2N₁And read the origin
A₀From the first defective pixel position A₁Relative distance to
Address data (RADR) is sent to the strobe generation circuit 28.
While latching the amplitude data (DCMA) and color
Mode data (DCC) and mode select data (DMS).
Latched in fifth to seventh latch circuits 25, 26, 27
I do. Then, the strobe pulse generation circuit 2
8 ends the initial setting operation and enters the correction operation state.
And the relative address data latched in the initial setting operation.
The first defective pixel position A based on the data (RADR)₁The timing of
Output a strobe pulse, and
The data 40 is incremented by
Next correction data (DCM) from data area ARCM_TwoRead
And a relative address indicating the distance to the next defective pixel position A1.
When the data is latched in the strobe generating circuit 28,
In addition, its amplitude data (MCMA) and color code data (DC
C) and mode select data (DMS)
And latched by the seventh latch circuits 25, 26, 27,
Pixel position A_N Strobe pulse sequentially at the timing of
The operation to output to is performed. The first to third latch circuits 21 and 2
2 and 23 are minimum correction amplitude data areas of the memory 10.
Minimum complement of each RGB channel read from ARSA
Latch the positive amplitude data (DSAR), (DSAG), and (DSAB), and
Select small correction amplitude data (DSAR), (DSAG), (DSAB)
Is supplied to the comparator 30 via the. Further, the fourth latch circuit 24 is provided with
From the shutter speed data area ARSS of the memory 10
The shutter data (SHD) to be read is latched and the shutter
Bit data (SHD) as control data.
Supply to road 31. Further, the fifth to seventh latch circuits
25, 26, 27 are the correction data areas A of the memory 10
Amplitude of correction data (DCM) read from RCM
Data (DCMA), color code data (DCC) and mode
Select data (DMS) is latched. Then, the fifth latch circuit 25 latches
The touched amplitude data (DCMA) is sent to the comparator 30.
Supplied and directly and above bit shift circuit
31 to a first switch circuit 32,
Digital / analog (D / A) conversion from one switch circuit 32
Is supplied to the exchange 33. The sixth latch circuit 26
The touched color code data (DCC)
29 as control data, and will be described later.
The data is supplied to the first decoder 43 as control data. Sa
The mode latched by the seventh latch circuit 27
The select data (DMS) is transmitted to the first switch circuit 32.
As control data, and a second
To the switch circuit 41 and the second decoder 47 of FIG.
And supplied as control data. The selector 29 is connected to the first to third selectors.
RGB latched by the latch circuits 21, 22, and 23
Minimum corrected amplitude data (DSAR), (DSAG), (DSA
Regarding B), the control data from the sixth latch circuit 26
Specified by the color code data (DCC) supplied as
Minimum amplitude correction data for any of the RGB channels
(DSA) is selected and supplied to the comparator 30. Up
The comparator 30 is selected by the selector 29.
Minimum corrected amplitude data (DSA) and the fifth latch circuit
Comparison with the amplitude data (DCMA) latched in 25
The comparison output is used as control data for the third switch
To the path 42, and the amplitude data (DCMA)
If it is larger than the amplitude data (DSA), the third switch
Switch 42 is closed. Also, the bit shift circuit 31
Amplitude data (DCMA) supplied from the fifth latch circuit 25
And the control data from the fourth latch circuit 24
Depending on the shutter data (SHD) supplied as
Bit shift processing as shown in Table 1 is performed,
The amplitude data (DCMA) that has been
The signal is supplied to the D / A converter 34 via a path 32. [0036] [Table 1] The first switch circuit 32 is connected to the seventh switch circuit 32.
Mode select data supplied from the latch circuit 27
(DMS) as control data, the mode select data
If (DMS) indicates white defect mode,
Select the shift circuit 31, and in the case of another defect mode,
The control is performed so as to select the fifth latch circuit 25. The D / A converter 33 is connected to the
The amplitude data (D
CMA) into analog. Obtained by the D / A converter 33
The analog amplitude signal is adjusted by first and second level adjustments.
Circuits 34, 35 and the first and
2 temperature correction circuits 14, 15
34, 35, 14, 15 to the first to fourth signal switching circuits
Various amplitude correction signals are output through paths 36, 37, 38 and 39.
Output selectively. The strobe generating circuit 28
The shutter speed data area ARSS of the memory 10
Address data (FADR) read from
Read from the correction data area ARCM of the memory 10
Relative data (RAD) of the correction data (DCM)
R), each CCD image forming the imaging unit 2
Each defective pixel position A of the image sensor 2R, 2G, 2B₁, A_Two
Generates strobe pulse at timing corresponding to ...
Then, the strobe pulse is supplied to the second switch circuit 41.
Directly through the third switch 42 and from the first
And the first address described above.
The data and relative address data are
The counter is preset in the counter 40. The second switch circuit 41 is connected to the seventh switch circuit 41.
Mode select data (D
MS) as control data, and the mode select data (D
MS) indicates the white defect mode, the third scan
Select the switch circuit 42, and in the case of another defect mode,
The first decoder 43 is controlled to select the first
The strobe pulse of the defect mode is turned on by the third switch.
The signal is supplied to the first decoder 43 through a path 42,
The strobe pulse in the defect mode is supplied to the first decoder 4.
Feed 3 directly. Further, the third switch circuit 42
Opens the output of the comparator 30 as control data.
By performing the closed control, the fifth latch circuit 25
The latched amplitude data (DCMA) is stored in the selector 29.
Larger than the minimum corrected amplitude data (DSA) selected in
Only when supplied via the second switch circuit 41
The strobe pulse of the white defect mode to be used
The data is supplied to the decoder 43. The first decoder 43 is provided with the sixth decoder 43.
2 bits supplied as control data from the latch circuit 26
Color code data (DCC) as shown in Table 2.
Any RGB channel or all channels selected and specified
Via channel D-type flip-flops 44, 45, 46
To supply the strobe pulse to the second decoder 47.
Pay. [0042] [Table 2] Each of the D-type flip-flops 44, 45, 4
6 is the above-mentioned CCD image sensor 2R, 2G, 2B
Each color component of the obtained imaging output, that is, each RGB channel
Clock pulse (φ_R), (φ_G), (φ_B) But
From the timing generator 5 to each clock input terminal
Supplied from the first decoder 43.
The above clock pulse
(φ_R), (φ_G), (φ_B) To adjust the phase. And on
In this embodiment in which the spatial picture element shifting method is adopted for the imaging unit 2
Is the clock pulse (φ_R), (φ_G), (φ_B) Out of G
Clock pulse for channel (φ_G) To other R, B Chang
Clock pulse (φ_R), (φ_B)
Therefore, the above imaging configured by using the spatial picture element shifting method
Obtained by each CCD image sensor 2R, 2G, 2B of section 2.
Each color component of the image pickup output, that is, each RGB channel
To get a strobe pulse that matches the phase of
You. The second decoder 47 is provided with the seventh decoder.
2 bits supplied as control data from the latch circuit 27
As shown in Table 3 in the mode select data (DMS)
Select control data according to the correction mode specified in
The first to fourth signals are formed from a strobe pulse.
Control input terminals of the correction signal switching circuits 36, 37, 38, 39
Give to. [0045] [Table 3] Then, the first to fourth correction signals are turned off.
The conversion circuits 36, 37, 38, and 39 are provided with the D / A converter 33.
From the first or second level adjusting circuits 34 and 35
Or the first or second temperature correction circuits 14 and 15
Each analog amplitude signal output via the
Switch as follows according to the selection control data by the coder 47.
Instead, it is output as various correction signals. That is, the mode select data (DM
When (S) indicates {kL} white defect mode,
The third correction signal switching circuit 38 is connected to the D / A converter 33.
Output through the first temperature correction circuit 14 from the
The analog amplitude signal is converted to the white defect correction signal (W_CP)
RGB channel indicated by color code data (DCC)
Selectively output to channels. In addition, the above mode select
If the data (DMS) indicates the black defect mode
In this case, the first correction signal switching circuit 36 sets the D / A
From the converter 33 via the first level adjustment circuit 34
The output analog amplitude signal is converted to the black defect correction signal (B_CP)
As shown in the color code data (DCC) above.
Selectively to the RGB channels. In addition,
The mode select data (DMS) is ≠ gL ≠
Switching mode, the fourth correction signal switching is performed.
A circuit 39 is provided from the D / A converter 33 to the second temperature compensator.
The analog amplitude signal output via the positive circuit 15 is
The edging correction signal (B_SH)
RGB channel indicated by the load data (DCC)
Selective output to the channel. Furthermore, the above mode selection
Data (DMS) is set to {gH} white shading mode.
The second correction signal switching circuit 37
From the D / A converter 33 to the second level adjustment circuit 3
5 converts the analog amplitude signal output via
Compensation signal (W_SH) As the color code data (D
Selectively output to RGB channel indicated by (CC)
I do. Further, in this embodiment, the memory
Correction data (DCM) from 10 correction data areas ARCM
Read out the various correction signals (W_CP), (B_CP), (W
_SH), (B_SH) Is formed as shown in FIG.
Each of the CCD image sensors 2R, 2 constituting the image section 2
Timing of reading signal charges from each defective pixel of G and 2B
The reading of the correction data (DCM)
(T_R) And a period of several tens of clocks before and after (T_R)
Other than shutting off the power supply to the memory 10 or
Perform power save control. Thereby, the memory 10
To reduce unnecessary power consumption by power consumption
Like that. In this embodiment, the space picture elements
R, G, and B channels obtained by the image pickup unit 2 using the Rashi method.
Channel color image output (S_R), (S_G), (S_B) Is the above D /
About the analog amplitude signal output from the A converter 33,
At the D-type flip-flops 44, 45, 46
The second data for the aligned strobe pulse
The decoded output from the coder 47 is used as the selection control data.
The first signal forming the correction signal switching circuit 12
And the third correction signal switching circuits 36, 38
Raw position A₁, A_TwoAccording to the defect mode at the timing of ...
Defect correction signal obtained by switching and selecting
No. (W_CP) And black defect correction signal (B_CP) Is the correction signal
By adding in the arithmetic circuit 8, white defects and
Correction processing of an image defect due to a black defect is performed. Selected by the first correction signal switching circuit 36
White defect correction signal (W_CP) Is, as shown in FIG.
Analog amplitude signal output from the D / A converter 33
Amplitude (l_W), Each of which constitutes the imaging unit 2
Detects the temperature of CCD image sensors 2R, 2G, 2B
The detection output from the temperature sensor 13 is supplied.
The first temperature correction circuit 14 performs a temperature correction process.
And white scratches at the operating temperature in the actual imaging state
The amplitude (l_W'), The imaging unit 2
Is added by the correction signal adding circuit 8
To optimize temperature-dependent white spot defects
Can be corrected. Here, the above-mentioned temperature-dependent white defect defect
The defect level is extremely small at normal temperature
At an exponential level at high temperatures
The white defect correction signal (W_CP) To temperature
The first temperature correction circuit 14 or the like that performs the correction process performs a correction error.
If there is a difference, the white defect correction signal (W_CP) Due to missing white wound
Overcorrection or uncorrection occurs in defect correction, so-called correction flaws are defect correction
It will remain in the processed imaging output. Therefore,
In this embodiment, the shutter speed is set by the initial setting operation described above.
Data such as speed and operating temperature are used as address data.
Read from the minimum corrected amplitude data area ARSA of the memory 10.
The minimum correction amplitude data (DSA) that is output
First to third latch circuits 21, 22, 2 of the raw circuit 11
3 during the actual imaging operation.
Correction amplitude read from correction data area ArcM of 0
Data (DCMA) is smaller than the above minimum corrected amplitude data (DSA)
A defect that may cause correction flaws due to white flaw correction
Do not perform correction processing for small white defect
To select only white defects with high defect levels
The above-mentioned white defect correction processing
Is more effective. Each CC constituting the image pickup section 2
In the D image sensors 2R, 2G, and 2B, the charge accumulation time
When an electronic shutter function by control is added,
Image output according to load accumulation time, that is, shutter speed
, The signal level of the white defect signal included in the image changes. this
In the embodiment, the correction signal is generated by the initial setting operation.
The latch latched by the fourth latch circuit 24 of the raw circuit 11
Bit shift circuit 31 based on the
Bit shift processing shown in Table 1 during the imaging operation of
To the corrected amplitude data (DCMA)
White defect correction signal (W_CP) Gay
And always perform the optimal white defect correction processing.
Can be. Note that the set shutter speed has white scratches.
Defect correction signal (W_CPIn order to make the gain
In addition to the shutter shift circuit 31, for example,
White defect defect correction using the charge accumulation time as a coefficient.
Signal (W_CP) Digital or analog multiplication
May be provided. Further, each CCD image of the image pickup unit 2
In the sensors 2R, 2G, and 2B, the charge accumulation time is controlled.
When the electronic shutter function is added, for example, as shown in FIG.
Charge accumulation in the field readout mode
The signal charge obtained by halving the period is also the normal mode
Is effective in the frame read mode.
The charge storage time is reduced to 1/4 of the normal mode,
Even if the same shutter speed is set, signal charges are read out
Since the effective charge storage time differs depending on the mode,
The signal level of the white defect signal included in the force is also different.
In this embodiment, field reading is performed on the memory 10.
Providing an area ARFD and a frame readout area ARFM,
Minimum correction amplitude data (DSA) in each read mode,
Write the normal data (DCM) and shutter data (SHD) in advance
The read mode that is actually set.
Field readout area ARFD or frame
Read data from the program read area ARFM and
By performing the initial setting operation and correction operation of
Perform optimal defect correction processing even in these read modes
Can be. Also, in this color video camera,
Image defects due to white and black defects
The signal processing system 9
In the correction signal switching circuit 12
The second and fourth correction signal switching circuits 36, 38
The analog amplitude signal output from the D / A converter 33 is missing.
By switching and selecting according to the
Black shading correction signal (B_SH) And white shading
Correction signal (W_SH) To perform shading correction processing.
It is. Selected by the fourth correction signal switching circuit 39
Black shading correction signal (B_SH) Is the above D / A
The amplitude of the analog amplitude signal output from the converter 33.
And the detection output from the temperature sensor 13 is supplied.
The second temperature correction circuit 15 performs a temperature correction process.
By doing so, the operating temperature in the actual imaging state
Can reduce shading to the minimum.
You. Accordingly, in this embodiment, the spatial picture element shifting
CCD image forming the imaging unit 2 adopting the
Phase of each imaging output from the image sensors 2R, 2G, and 2B.
Defect correction signal generated by the correction signal generation circuit 11
Then, the white of each of the CCD image sensors 2R, 2G, 2B
Correct image defects caused by scratch defects, black defect defects, etc.
To obtain an imaging output signal with extremely good image quality
Can be. [0057] According to the video camera of the present invention, the solid-state
The position of defective pixels contained in the image element and the output signal
A record that stores data on the level of contained defect components
Data read from storage means and the default
Means for generating a defect correction signal based on the
Generates a defect correction signal for the solid-state imaging device,
With respect to the output signal of the solid-state imaging device,
Since defect correction is performed, changes in shutter speed
Even if the defect level changes, it is caused by white defect, black defect, etc.
Image defects can be corrected appropriately, and image quality is extremely good
Good imaging output signals can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a configuration of a video camera to which the present invention has been applied. FIG. 2 is a schematic diagram showing a structure of a CCD image sensor constituting an imaging unit of the video camera. FIG. 3 is a schematic diagram showing an installation state of a CCD image sensor constituting an imaging unit of the video camera. FIG. 4 is a schematic diagram for explaining a pixel defect of the CCD image sensor and its imaging output. FIG. 5 is a memory map of a memory for storing data on pixel defects of the CCD image sensor. FIG. 6 is a block diagram showing a specific configuration of a correction signal generating circuit for reading out correction data from the memory and forming various correction signals together with its peripheral circuits. FIG. 7 is a timing chart showing a power save control operation of the memory by the correction signal generation circuit. FIG. 8 is a waveform diagram for explaining a defect correction processing operation using a correction signal formed by the correction signal generation circuit. FIG. 9 is a waveform diagram for explaining a relationship between a charge accumulation time and a charge accumulation amount in a field read mode and a frame read mode of the CCD image sensor. [Description of Signs] 2 imaging unit, 2R, 2G, 2B CCD image sensor, 3 CCD drive circuit, 4 sync generator, 5
Timing generator, 6 system controller, 8 correction signal addition circuit, 10 memory, 11 correction signal generation circuit, 12 correction signal switching circuit, 28 strobe generation circuit, 33 D / A converter, 41, 42 switch circuit, 43, 47 decoder , 44, 45, 46 D
Type flip-flop

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04N 5/30-5/335

Claims (1)

(57) [Claims] In a video camera having a solid-state imaging device, storage means for storing data on a position of a defective pixel included in the solid-state imaging device and a defect component level included in an output signal thereof, and initializing data read from the storage means A defect correction signal generating means for generating a defect correction signal for the solid-state imaging device according to the shutter speed by performing level control based on the shutter speed data that has been set; and the solid-state imaging device based on the defect correction signal. A video camera, comprising: a defect correction unit that performs defect correction on an output signal of an element.