JPS6083485A - Image pickup device - Google Patents

Abstract

PURPOSE:To obtain an image pickup device which reduces color mixture by storing temporarily information from an image pickup part including plural horizontal line sensors arrayed vertically and reading the information, line by one, successively. CONSTITUTION:The image pickup part 1 includes the horizontal line sensors 100-300 arrayed vertically, and charges in the line sensors are transferred to a buffer part 2 by transfer electrodes provided on a semiconductor substrate across an insulating layer. A color separation filter CF having a color repetitive pattern with a specific period horizontally is arranged on the front surface of the image pickup part 1. The buffer part 2 consists of linear CCDs 104-107 for time-axis conversion, and charges of the respective CCDs are transferred to a storage part 3 through the transfer electrodes. This transfer is stopped intermittently by a driving means within a transfer period. The storage part 3 consists of linear CCDs 118-111 and the charges stored therein are read out successively to a shift register 4 in sequential vertical arrangement and sent out through an output printer.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an improvement in an imaging device including a plurality of horizontally arranged line sensors.

(Prior art) Conventionally, for example, in order to convert one image's worth of image information into two fields' worth of sequential signals, an interline transfer type C was used.
It was thought that there would be an OD or MO8 type seven-sensor.

However, these sensors have a drawback that the aperture ratio is small because a transfer path, a gate, etc. are provided within the light receiving surface, and the sensor sensitivity is reduced.

Furthermore, from the perspective of semiconductor manufacturing technology, it requires a high degree of integration, resulting in poor yields and the disadvantage that the number of pixels cannot be increased.

On the other hand, frame transfer fi! These drawbacks can be eliminated by using an ICCD, but it has been said that the frame transfer type cannot convert one image into a two-field sequential signal.

In response to this, the applicant proposed an imaging device capable of eliminating these five drawbacks in Japanese Patent Application No. 138551/1982.

That is, we have proposed an imaging device that is configured using a plurality of horizontally arranged two-in-sensors, thereby making it possible to obtain interlaced two-field signals in one imaging operation.

The object of the present invention is to provide an imaging device that further improves the color mixture and has less color mixture.

(Example) The present invention will be described in detail below based on Examples.

Figure 1(a) is a diagram showing an example of the configuration of a sensor @ element B which is suitable for the imaging device of the present invention. Figure 51(b) is a diagram of the electrode arrangement. 6 is a storage section, 4 is a COD structure shift register as a readout section, and 5 is an output amplifier.Everything other than the imaging section is shielded from light.

The imaging unit 1 consists of a plurality of horizontally arranged line sensors 101 to 106 having a transfer function, and the charges in each line sensor are transferred simultaneously by a transfer electrode 60 provided on a semiconductor substrate with an insulating layer interposed therebetween. Transferred to the left.

Each line sensor is also spaced apart by a channel stop C8.

The buffer part 2 consists of the same number of linear CCDs 104 to 107 for time axis conversion as the imaging part 1, and each linear CCD
In this embodiment, each CD has a capacity of 6 pits.

Further, the charges of the line-shaped CCDs in the buffer part 2 are simultaneously horizontally transferred one bit at a time to the left in the figure by the transfer electrodes 61 to 66.

The storage section 6 has the same number of horizontally arranged line Cs as the imaging section 1.
It consists of CDs 108 to 111, and the electrodes of each line-shaped COD are horizontally transferred to the left in the figure by transfer electrodes 64 to 37, respectively.

38 is a transfer electrode for vertically transferring the charges in the shift register 4 downward in the figure.

In this embodiment, an example of a single-phase drive type CCD of 47η is shown.

Also, when a high-level voltage is applied to each transfer electrode, the potential level in the substrate becomes relatively low below the electrodes when viewed from the electrons, forming a well and collecting charges under each electrode. It is configured.

Also, when the voltage applied to the transfer electrodes is set to a low level, a potential well is formed relative to the area not covered by the adjacent left or lower adjacent electrode of each transfer electrode.
The structure is such that the charges that have been collected under the transfer electrode are transferred to the left or downward.

Further, φl to φ9 indicate clock signals applied to the electrodes 60 to 38, respectively.

On the surface of the imaging unit 1, a color separation filter CF having, for example, vertical striped color filters as shown in the second diagram is arranged.

This color separation filter is B (blue), G (green), XR (red)
It has a structure in which six striped color filters are repeatedly arranged in this order in the horizontal direction at a period of six.

The present invention is not limited to a striped color separation filter having a repeating pattern in the horizontal direction (it also includes a mosaic color separation filter having a repeating pattern of color filters in the vertical direction).

FIG. 6 is a diagram showing an example of the configuration of an imaging device according to the present invention.
, are imaged on the image sensor B via the color separation filter CF. No. 11 is the clock generator of the present invention, and the fourth
The output of the clock generator 11 that forms various clock pulses φl to φ9 as shown in the figure is appropriately amplified by the driver 10 and then supplied to the image sensor B. This clock generator 11 and driver 10 form a driving means.

As a result, as will be described later, a dot-sequential color signal is output from the image sensor 6.

This dot-sequential color signal increases the duty cycle ratio by the sample-and-hold circuit 12 and facilitates subsequent sample-and-hold for each color.

Reference numerals 13 to 15 are sample-hold circuits for holding samples for each color as described above, which sample the dot-sequential color signal at a period corresponding to the color line repetition period of the color filter and at a phase for each color. .

16 to 19 respectively] and PF, where l and PF'16 have a cutoff of, for example, about 3 MHz, and l and PF'1
7 to 19 have a cutoff of about 5QQKHz, for example.

20 to 23 are process circuits, each having an LPF of 16 to 23.
Various corrections such as black level clamping, gamma correction, white clipping, and APC are applied to the signal that has passed through step 19.

24 is a matrix circuit, which includes process circuits 20 to 26;
For example, from the Y, B, G, and R signals obtained through
, RY, and B-Y.

Reference numeral 25 denotes an encoder which uses the luminance signal and color difference signal to form a standard 1+A television signal such as an NTSC signal.

25 is a recording device for recording this standard television signal.

Next, an example of the output of the driver 10 and clock generator 11 shown in FIG. 6 will be explained using FIG. 4, and the operation of the configuration shown in FIG. 1 will be explained.

In FIG. 4, Vs is the vertical scanning period of the standard television signal, and VBLK is the vertical blanking period. It is temporarily stored in the storage part B via the buffer part 2.

As described above, this horizontal transfer is performed for one bit each time the voltage applied to each electrode is once set to high level and then lowered to low level.

Therefore, as shown in Figure 1 (in the case of an imaging section having pixels of 6 horizontal bits x 4 vertical pits), since the buffer section has 6 bits, if a 9-bit clock pulse is supplied as φl, 1
Transfer of one screen is achieved.

In the present invention, the clock generator 11 temporarily transfers the charges in the imaging section 1 to the storage section B at times t2 to t3 and from t4 to t5 during the period VBL for horizontal transfer.
．． The transfer operation is stopped between t6 and ty.

In this embodiment, the transfer operation is intermittently stopped at a period corresponding to the horizontal color repetition period of the color separation filter C8, that is, every 6 bits.

Therefore, for example, the signal corresponding to R (red) accumulated at point 3 in FIG. After that, it is transferred to the position of the turning screw ■→■→■, and then sequentially transferred to the position of →6' of →◎→.

In this way, even during horizontal transfer, the time when charges stay at the position of the same color filter is relatively long, and the time when charges stay at the position of different color filters is relatively short. Charges corresponding to different colors formed when passing under different color filters are reduced.

Therefore, color mixing during transfer is prevented from occurring in an imaging device that includes a color repetition pattern with a predetermined period in a direction perpendicular to the transfer direction of each 2-in sensor of the imaging unit, and color reproducibility can be improved.

Further, in this embodiment, a buffer unit 2 is provided, and the pulse φl including the intermittent transfer stop point is delayed by a predetermined width to gradually stop the pulse φ1 to φ9 to receive the charge from the imaging unit 1. I can do things.

Therefore, the storage section has a complicated structure because each line-shaped CCD is driven independently, and the transfer efficiency may drop slightly, but by providing this buffer section 2, it is necessary to drive the storage section at high speed. (This means that transfer efficiency can be maintained.

The charges accumulated in the storage unit B at a relatively low speed during the period VBLK are then read out in the first row by supplying the pulse φ5 and the pulse φ9 during one horizontal period from time 17 to t8. , then from time 18 to t
The second row is read out by supplying pulse φ6 and pulse φ9 in one horizontal period of 9.
The signals for one screen formed by the above are sequentially read out line by line.

Note that the pulse φ9 is always supplied at high speed.

Next, FIG. 5(a) is a diagram showing a second embodiment of the imaging device of the present invention, and FIG. 5(b) is a timing chart thereof,
In this embodiment, the structure is simplified by omitting the buffer section in the image pickup device shown in the first diagram.

In the figures, the same reference numerals as in FIGS. 1 to 4 indicate the same elements.

39 is a driver circuit for driving the image sensor, 40 is a clock generator circuit, and the circuits 39 and 40 form driving means. As shown in FIG. 5(a), since the buffer section 2 is omitted in this embodiment, the structure is simpler and the yield can be improved.

Also in this embodiment, the filter CF shown in the second diagram is arranged on the imaging section 1.

Next, the operation of the clock generator 40 of this embodiment will be explained using the timing chart shown in FIG. 5(b).

During the period VBLK from time to t16, the electric charge of each line sensor in the imaging section 1 is horizontally transferred to the corresponding line-shaped CCD of the storage section B by six pulses φ1 to φ8.

At this time, in this embodiment, time till to t14. Time t1
5 to t16, since the transfer is intermittently stopped, color mixing is prevented from occurring as in the first embodiment.

Moreover, in this embodiment, fewer pulses are required for horizontal transfer, and pulses for driving the bumper section 2 are also omitted, so the configuration of the clock generator circuit 40 is simplified.

Incidentally, since the load of the imaging section 1 has been accumulated in the storage section 6 by time t16, the same readout as in the embodiment shown in the fourth figure is performed from the clock generator circuit 401c during the vertical scanning period from time 117 to 118. For (J) Pulse φ
5 to φ8 is supplied. Further, although the pulse φ9 is not shown, it is always supplied as a high-speed pulse.

Also, 1st. The second embodiment shows an example in which the transfer is stopped intermittently during horizontal transfer, but in general frame transfer type COD or interline type COD, a color separation filter having a repeating pattern in the vertical direction is used. Even in such a case, if the transfer is stopped intermittently during vertical transfer, the same effect of preventing color mixture as in the present invention can be obtained.

Therefore, it goes without saying that the present invention is also effective for these five configurations.

(Effects) As explained above, the imaging device of the present invention includes an imaging section including a plurality of vertically arranged horizontal line sensors, and a color reproducing unit arranged in front of the imaging section at a predetermined period in the horizontal direction. a color separation filter having a crisscross pattern; a driving means configured to horizontally transfer the information accumulated in each of the line sensors for a predetermined period of time and to intermittently stop the transfer within the transfer period; and each of the lines. It has a storage section for temporarily storing information horizontally transferred from the sensor, and a readout means for sequentially reading out 1W information from the storage section one line at a time, so color mixing is less likely to occur when horizontally transferring information from the imaging section. , color reproducibility is improved.

[Brief explanation of drawings]

FIG. 1(a) is a diagram showing the configuration of a first embodiment of an image sensor suitable for the present invention, FIG. 1(b) is an electrode diagram thereof, FIG. 2 is a diagram showing an example of a color separation filter, and FIG. 3 is a diagram showing a first embodiment of the projection device using the image pickup device shown in FIG. 1, and FIG. 4 is a timing chart 1 of the image pickup device shown in FIG.
) is a diagram showing the second embodiment of the imaging device of the present invention, and FIG.
b) is its timing chart. 100 to 106... line sensor, 1... imaging unit, C8... color separation filter, 1o, filter 9... driver, 11, 40 are clock generators, 10, 11, 39 and 40 respectively , a driving means is configured. 6...Storage unit, 4...Readout unit.

Claims (1)

[Claims] an imaging unit including a plurality of horizontal line sensors arranged in the vertical direction; a color separation filter disposed in front of the imaging unit and having a color ib return pattern with a predetermined period in the horizontal direction;
The information horizontally transferred from each of the two innancers to a driving means that horizontally transfers the information detected by each of the line sensors for a predetermined period and intermittently stops the transfer within the transfer period. An imaging device that has a storage section for temporarily storing information and a reading section that sequentially reads out information from the storage section one line at a time.