JPS62271565A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To prevent the occurrence of a smear signal and to attain a quick shutter action by fitting a rotary shutter on a solid-state image pickup device with an electronic shutter and light-shielding an image pickup element when a charge is transferred to an accumulation part from an image pickup part. CONSTITUTION:The solid-state image pickup element 2 is constituted of the image pickup part 2a, the accumulation part 2b to accumulate charges obtained by image-picking up, an output register 2c to sweep out accumulated charges and an overflow drain 2d. A drive circuit 3 drives the image pickup element 2 so as to give an electronic shutter function to said element 2. When a shutter command is inputted from a terminal 10, the image pickup part 2 is cleaned and charges arising so far are removed. Due to the drive of the circuit 3, the electronic shutter operates from the time when cleaning ends to the time when the rotary shutter 6 is closed. Charges caused by exposure are transferred to the accumulation part 2b. During the transfer, the shutter 6 is closed, and the register 2c is light-shielded, thereby preventing the occurrence of the smear signal. The charges in the accumulation part 2b are read out, which a signal processing circuit 5 stores in a field memory 8.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Industrial Application] This invention relates to a solid-state imaging device with a shutter function.

[Conventional technology]

Conventionally, a solid-state imaging device with a shutter function has been configured as shown in FIG. 5 or 6.

In the apparatus shown in FIG. 5, a rotary shutter attached to the front surface of the lens periodically performs a shutter operation to capture video signals of a necessary time into a memory.

In FIG. 5, l is a lens, 6 is a rotary shutter attached to the front surface of lens 1, 18 is an image sensor, and 3
4 is a drive circuit that drives the image sensor 18, 4 is a synchronization signal generation circuit, 5 is a signal processing circuit that generates a video signal based on the signal from the image sensor 1B, 8 is a field memory that stores a video signal at an arbitrary time, 7 is rotary shutter 6
9 is a video output, and 10 is a shutter command input terminal. In the apparatus shown in FIG. 5, a rotary shutter 6 periodically performs a shutter operation, and a control circuit 7 captures video signals of a necessary time into a field memory 8.

Further, the apparatus shown in FIG. 6 uses an image pickup element equipped with an image pickup section, an accumulation section, and a charge sweep-out section, and changes the driving method of the element to electronically provide a shutter function. In FIG. 6, reference numeral 2 denotes an image sensor to which an electronic shutter function can be added, and its structure is shown in FIG.

In Fig. 2, 1) is an imaging section, 12 is an accumulation section that stores charges accumulated in the imaging section 1), and 14 is an imaging section 1).
15 is an accumulation section transfer register that transfers the charges stored in the accumulation section 12 to the output register 16; 16 is an accumulation section transfer register; 15 is an output register that sequentially outputs the charges transferred; 13 is an overflow drain (cleaning drain) that releases the charges overflowing from the output register 16; and 17 is an output terminal of the image sensor.

FIG. 7 shows the operating timing of the device of FIG.

In the figure, VD is a vertical synchronization pulse, SP is a shutter command pulse, GP is a register control pulse for controlling the imaging unit transfer register 14, storage unit transfer register 15, and output register 16, PI is an imaging unit transfer pulse, and PS is a The storage section transfer pulse, T is the output pulse, and MP is the memory control pulse. Note that S L is the shutter opening time.

Next, the operation of the apparatus shown in FIG. 6 will be explained using FIG. 7. If there is no shutter command, time t13-t
14, the vertical synchronizing pulse VD is fed back to the register control pulse GP, and the imaging unit transfer pulse P■,
Accumulator transfer pulse ps.

The output pulse T is output as shown in the figure, and charge is transferred from the imaging section 1) in FIG. 2 to the storage section 12, and at time t.
Accumulator transfer pulse ps after 14.

The charges in the storage section 12 are sequentially read out using the output pulse T. This is the operation during normal imaging. When the shutter command pulse SP is input from the shutter command input terminal 10 at time t14, charge is transferred from the imaging section 1) to the storage section 12 between times t16 and t17 by the register control pulse GP at time t15.

Next, time (time t by 16 register control pulses GP)
Charges generated in the imaging unit 1) by exposure between times t17 and tlB are transferred to the storage unit 12 between times t18 and t19. The charges that had been transferred between times t16 and t17 are swept out to the cleaning drain 13 when the charges generated in the sacrificial image area 1 due to exposure between times t17 and tlB are transferred to the storage section 12. Only the charges at intervals indicated by the shutter time St are stored in the storage section 12, but the image capturing section 1) also stores charges during charge transfer to the storage section 12, that is, between times t18 and t19. remains exposed, which causes a smear signal. The charges stored in the storage section 12 in this manner are sequentially read out by the storage section transfer pulse PS and the output pulse T after time t19.

The memory pulse MP informs the field memory 8 that a shutter operation has been performed, and the charge read out from the image sensor 2 is converted into a video signal by the signal processing circuit 5 and then stored in the field memory 8.

[Problem that the invention seeks to solve]

Conventional solid-state imagers with rotary shutters use a rotary shutter, so they have the disadvantage that only images can be obtained when the shutter is operating, and the configuration of the rotary shutter is difficult to achieve high-speed shutter operation. There were such problems.

Furthermore, in solid-state imaging devices with electronic shutters, the imaging section remains exposed during charge transfer from the imaging section to the storage section, resulting in problems such as generation of smear signals.

This invention was made in order to solve the above-mentioned problems, and it is a solid-state product that prevents the generation of smear signals, enables high-speed shutter operation, and makes it possible to obtain both normal TV images and shutter images. The purpose is to obtain an imaging device.

[Means for solving problems]

A solid-state imaging device according to the present invention includes a rotary shutter attached to an electronic shutter-equipped stationary imaging device to shield an imaging element from light during charge transfer from an imaging section to a storage section.

[Effect]

In this invention, the rotary shutter shields the image sensor from light during charge transfer from the imaging section of the image sensor to the storage section, and also closes the open time of the electronic shutter, so that the image sensor is not exposed to light. Since the shutter function itself is realized by an electronic shutter, high-speed shutter operation can be realized using an inexpensive rotary shutter.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a solid-state imaging device according to an embodiment of the present invention,
In the figure, 1 is a lens, 2 is an image sensor, 3 is a drive circuit that drives the image sensor 2, 4 is a synchronization signal generation circuit, 5 is a signal processing circuit that generates a video signal based on the signal from the image sensor 2, and 6 is a signal processing circuit that generates a video signal based on a signal from the image sensor 2. A rotary shutter is attached to the front surface of the lens 1 and is opened for a certain period of time in accordance with the field cycle; 7 is a control circuit that controls opening and closing of the rotary shutter 6 and a memory 8; 8 is a field memory that stores a video signal of an arbitrary field; 9; 1 is a video output, and 10 is a shutter command input terminal.

The image sensor 2 in FIG. 1 has a configuration as shown in FIG. 2, and by driving an electronic shutter at the drive timing shown in FIG. 3, charges are swept out and the shutter is in an open state. Create. Further, the rotary shutter 6 closes the electronic shutter and shields the imaging unit transfer register 14 from light during charge transfer from the imaging unit 1) of the imaging device 2 to the storage unit 12, thereby preventing generation of a smear signal. .

Next, the operation of the above embodiment will be explained with reference to FIGS. 3 and 4. When a shutter command is input from the shutter command input terminal 10 at time 0 t2, a register control pulse is generated in the circuit shown in FIG. In addition to the pulse caused by the vertical synchronizing pulse VD between time t6 and t8, a pulse is input to GP between time t3 and t6 as shown in the figure. The imaging section 1) is cleaned by these pulses, and the charges generated up to that point are removed. The electronic shutter time SL is a period from the time when cleaning ends at time t6 to time t7 when the rotary shutter 6 is in a closed state.

The charge generated by the exposure from time t6 to t7 is transferred to time t by the register control pulse GP between time t6 and t8.
The data is transferred to the storage unit 12 between 8 and t9. During this time,
The rotary shutter 6 remains closed, and the image pickup unit transfer register 4 is shielded from light to prevent the generation of smear signals.

Next, between times t9 and tlO, the charges stored in the storage section 12 are read out and stored in the field memory 8 as a video signal in the signal processing circuit 5 in accordance with the signal of the memory control pulse MP. In this way, the electronic shutter operation is completed between time t2 and tlo, and the normal imaging operation resumes from time tlo.

In this example, a rotary shutter with a slow shutter speed was used to shield the imaging section from light during charge transfer to the charge storage section of a gymnastics imaging device equipped with an electronic shutter, so there is no need to increase the speed of the rotary shutter, and the smear signal can be obtained at low cost. We have achieved a solid-state imaging device with a high-speed shutter function.

In the above embodiment, the cleaning operation is performed by manually applying three pulses in addition to the vertical synchronization pulse to the register control pulse, but this number of pulses is necessary to completely clean the imaging section 1). Any number (1 to n) is sufficient.

〔Effect of the invention〕

As described above, the solid-state imaging device according to the present invention includes a solid-state imaging device with an electronic shutter attached with a rotary shutter vine,
When the charge from the imaging section is transferred to the charge storage section, the imaging section is configured to be shielded from light by the rotary shutter, so a rotary shutter with a slow shutter speed can be used to realize a high-speed shutter function that does not generate a smear signal. This has the advantage that the device can be made at low cost and highly accurate.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the solid-state imaging device 0 darkness according to an embodiment of the present invention, Fig. 2 is a block diagram of the solid-state imaging device of Fig. 1, and Fig. 3 is a timing diagram showing the operation of Fig. 1. Chart diagram, FIG. 4 is a diagram showing the configuration of the main pulse generation circuit in FIG. 1, FIG. 5 is a configuration diagram of a conventional solid-state imaging device with a rotary shutter, and FIG. 6 is a diagram of a conventional solid-state imaging device with an electronic shutter. FIG. 7 is a timing chart showing the operation in FIG. 6. In the figure, 1 is a lens, 2 is a solid-state image sensor, 3 is a drive circuit, 4 is a synchronization signal generation circuit, 5 is a signal processing circuit, 6 is a rotary shutter, 7 is a control circuit, 8 is a field memory, and 9 is a video output , 10 is a shutter command input terminal;
1) is an imaging section, 12 is an accumulation section, 13 is an overflow drain, 14 is an imaging section transfer pulse, 15 is an accumulation section transfer pulse, 16 is an output register, 17 is a sensor output terminal, 1
8 is a solid-state imaging device used in a solid-state imaging device with a rotary shutter. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] (1) A solid-state image sensor including an imaging section, an accumulation section for accumulating electrical signals obtained by the imaging, and a charge sweep section for discharging the accumulated charge, and the solid-state image sensor having an electronic shutter function. What is claimed is: 1. A solid-state imaging device comprising: a driving means for driving; and a rotary shutter for shielding the imaging section from light when charge is transferred from the imaging section to the storage section by the driving means.