JPH10150604A - Solid-state image pickup and transmission method for its output signal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit a picked-up image signal to an external device at a high speed. SOLUTION: A solid-state image pickup device using a CCD type image pickup elements whose image pickup area 13 is divided into halves, e.g. leads out two groups of pixel signals corresponding to respective divided areas 13L and 13R, mixes these two groups of pixels by a mixer 20 to generate image signals continuing on a time axis, modulates these image signals to optical outputs by a light source 21 and transmits these at a high speed through an optical fiber 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state imaging device and a method of transmitting an output signal of the solid-state imaging device. More particularly, the present invention relates to a solid-state imaging device that divides an imaging region into a plurality and outputs a plurality of pixel signals corresponding to each divided region. The present invention relates to a solid-state imaging device having the same and a transmission method for transmitting a plurality of pixel signals output from a solid-state imaging device in the solid-state imaging device.

[0002]

2. Description of the Related Art In recent years, in order to realize clear images, the resolution of solid-state imaging devices used as imaging devices for cameras has been increased. In particular, in a high-definition system which is expected to dramatically expand its application range not only in television broadcasting but also in various industrial fields such as printing and cinema due to its high resolution, a solid-state image sensor suitable for the system is 200 More than 10,000 pixels are required. As described above, when the number of pixels of the solid-state imaging device is increased, high-speed processing of a pixel signal output from each pixel is required.

As one prior art for that purpose, for example, CC
In a D-type imaging device, the imaging area is divided into, for example, four parts, and signal charges of each pixel in each divided area are transferred in the opposite direction by a vertical CCD and a horizontal CCD, respectively, in the division direction, and four types of pixel signals are transmitted. The present applicant has proposed a solid-state imaging device in which the time required for deriving all pixel signals is reduced to 1/4 by deriving the signal (see Japanese Patent Application Laid-Open No. Hei 5-22667).

[0004]

However, as described above, the time required for deriving all pixel signals can be reduced by dividing the imaging area into a plurality of parts and deriving pixel signals of a plurality of systems corresponding to each divided area. Even if it could be shortened,
It takes a long time to transmit the image signal because the derived multiple pixel signals are mixed to generate a continuous image signal on the time axis, and this is simply transmitted to the external device using the signal line. become.

Accordingly, an object of the present invention is to provide a solid-state imaging device capable of transmitting an image signal obtained by imaging to an external device at a high speed, and a method of transmitting an output signal thereof.

[0006]

According to the present invention, there is provided a solid-state imaging device according to the present invention, wherein an imaging region is divided into a plurality of regions, and a plurality of systems of pixel signals corresponding to each divided region are output. A signal processing circuit that generates a continuous image signal on the time axis by mixing pixel signals of a plurality of systems, a light source that modulates an image signal output from the signal processing circuit into an optical output, An optical fiber for transmitting an optical output to an external device.

According to the transmission method of the present invention, in a solid-state imaging device having a solid-state imaging device for dividing a plurality of imaging regions and outputting a plurality of systems of pixel signals corresponding to the respective divided regions, a plurality of signals output from the solid-state imaging device are provided. A pixel signal of a system is mixed to generate a continuous image signal on a time axis, the generated image signal is modulated into an optical output, and transmitted to an external device using an optical fiber.

In the solid-state imaging device and the transmission method having the above-described configurations, a plurality of pixel signals corresponding to each of the divided regions are output from the solid-state imaging device in which the imaging region is divided into a plurality. The pixel signals of these plural systems are mixed by adjusting the temporal positional relationship by the signal processing circuit, and become continuous image signals on the time axis. The image signal thus obtained is modulated by a light source into a light output, and then transmitted at high speed to an external device via an optical fiber.

[0009]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a schematic diagram showing a first embodiment of the present invention applied to, for example, an interline transfer type CCD type image pickup device. In FIG. 1, a plurality of sensor units 11 for converting incident light into signal charges having a charge amount corresponding to the light amount and storing the signal charges are two-dimensionally arranged in a matrix. Also, for each row of these sensor units 11, each sensor unit 11
Vertical CCD 1 for vertically transferring signal charges read from
2 are provided. These sensor unit 11 and vertical C
An imaging area 13 is constituted by the CD 12. This imaging region 13 is divided into two in the left-right direction in the figure, for example.

The vertical CCD 12 is driven by, for example, four-phase vertical transfer clocks φV1 to φV4, and performs vertical transfer by shifting signal charges in line units. The shift gates 14L, 14
Two horizontal CCDs 15L and 15R are provided corresponding to the left and right divided areas 13L and 13R of the imaging area 13 via R. By applying a shift pulse φSG to the shift gates 14L and 14R, the signal charges are shifted from the lowermost packet of the vertical CCD 12 to each of the divided regions 13L and 13R.

The horizontal CCDs 15L and 15R are driven by, for example, two-phase horizontal transfer clocks φH1 and φH2 to horizontally transfer the signal charges shifted from the vertical CCD 12 to each of the divided areas 13L and 13R. At the end of each of the horizontal CCDs 15L and 15R on the transfer destination side, for example, charge-voltage converters 16L and 16R having a floating diffusion amplifier configuration are provided. These charge-voltage converters 16L, 16R are connected to the horizontal CCDs 15L, 1L.
The signal charge sequentially transferred by the 5R is converted into a signal voltage, and the output circuit 17 converts the signal charge into a two-system analog pixel signal.
Output via L, 17R.

The analog pixel signal passed through the output circuit 17L is directly converted into an A (analog) / D (digital) converter 18
L and converted to a digital pixel signal. The analog pixel signal that has passed through the output circuit 17R is delayed by the delay circuit 19 by a delay time corresponding to the transfer time of the horizontal CCD 15L, and then supplied to an A / D converter 18R to be converted into a digital pixel signal.

The digital pixel signals of these two systems are alternately selected and mixed by the mixer 20, so that all the lines of the image pickup area 13 become digital image signals that are successively arranged on the time axis. The digital image signal is supplied to a light source 21, modulated into an optical output by the light source 21, and then transmitted at high speed to an external device (not shown) such as a disk device, a display device, or a printing device via an optical fiber 22. You.

As the light source 21, a semiconductor light source such as a semiconductor laser or a light emitting diode is used. This semiconductor light source has a feature that an optical output can be modulated at a high speed by superimposing a signal waveform on a driving DC current. Among the semiconductor light sources, a semiconductor laser has a high optical power level that can be taken into the optical fiber 22 and has a high modulation speed, and is therefore most suitable for high-speed transmission of image signals. On the other hand, the light emitting diode has a lower optical power level that can be taken into the optical fiber 22 and a lower modulation speed than the semiconductor laser, but is superior in that it is cheaper and more reliable than the semiconductor laser.

The optical fiber 22 is not only excellent in high-speed transmission of information but also low in loss, which is important for optical communication. Performance, small diameter, light weight, insulation, water resistance,
It has the feature of being excellent in fire resistance. Furthermore, since it transmits light, it has the feature of being resistant to electromagnetic noise.

As described above, in the solid-state imaging device using the CCD type image pickup device, the image pickup region 13 of the CCD type image pickup device is divided into a plurality of parts (in this example, divided into two), and the divided regions 13L, 13R By deriving the two types of pixel signals, the time required for deriving all the pixel signals can be reduced.
0 is mixed to generate a continuous image signal on the time axis, and this image signal is modulated into a light output by the light source 21 and transmitted at a high speed by the optical fiber 22, so that it is obtained by imaging. Image signals can be transmitted to an external device at high speed.

FIG. 2 is a schematic configuration diagram showing a second embodiment of the present invention applied to a MOS type image pickup device. 2, a unit pixel 33 is formed by a capacitor 31 and a MOS transistor 32, and the unit pixels 33 are two-dimensionally arranged in a matrix to form an imaging area. The imaging region 34 is divided into two in the left-right direction in the figure, for example. In each of the unit pixels 33, the gate electrode of the MOS transistor 32 is connected to the vertical selection line 35 in row units, and one main electrode is connected to the vertical signal line 36 in column units.
It is connected to the.

One end of the vertical selection line 35 is connected to a vertical scanning circuit 37.
Connected to the output end of each row. Vertical scanning circuit 37
Is constituted by a shift register or the like, and sequentially outputs a vertical scanning pulse φVm. One end of the vertical signal line 36 is M
It is connected to two horizontal signal lines 39L and 39R via a horizontal selection switch 38 composed of an OS transistor.
The gate electrode of the horizontal selection switch 38 has two gate electrodes provided corresponding to the left and right divided regions 34L and 34R of the imaging region 34.
The horizontal scanning circuits 40L and 40R are connected to output terminals of respective columns. The horizontal scanning circuits 40L and 40R are constituted by shift registers and the like, and have horizontal scanning pulses φHL.
n and φHRn are sequentially output.

The analog pixel signal led out to the horizontal signal line 39L is directly sent to the A / D converter 42 via the output circuit 41L.
L and converted to a digital pixel signal. The analog pixel signal led to the horizontal signal line 39R is delayed by the delay circuit 43 via the output circuit 41R by a delay time corresponding to the scanning time of the horizontal scanning circuit 40L, and then supplied to the A / D converter 42R. It is converted to a digital pixel signal. These two systems of digital pixel signals are supplied to a mixer 44.
Are alternately selected and mixed in the imaging area 3
All four lines are digital image signals that are successively arranged on the time axis.

The digital image signal is supplied to a light source 45, modulated into an optical output by the light source 45, and then transmitted to an external device (not shown) such as a disk device, a display device or a printing device at a high speed by an optical fiber 46. Transmitted. As the light source 45, a semiconductor light source such as a semiconductor laser or a light emitting diode is used as in the case of the above-described first embodiment.

As described above, in the solid-state image pickup device using the MOS type image pickup device, the image pickup region 34 of the MOS type image pickup device is divided into a plurality of parts (in this example, two divisions), and each of the divided regions 34L and 34R corresponds to each of the divided regions 34L and 34R. By deriving the pixel signals of the two systems, the time required for deriving all the pixel signals can be reduced, and the pixel signals of the two systems can be mixed by the mixer 4.
4 to generate a continuous image signal on the time axis, modulate this image signal into a light output by the light source 45, and transmit it at a high speed by the optical fiber 46. Image signals can be transmitted to an external device at high speed.

FIG. 3 is a schematic configuration diagram showing a third embodiment of the present invention applied to an amplification type imaging device. In FIG. 3, a unit pixel 53 is formed by a capacitor 51 and an active element 52 having an amplifying function. The unit pixels 53 are two-dimensionally arranged in a matrix to form an imaging area 54.
The imaging region 54 is divided into two in the left-right direction in the drawing, for example. In each of the unit pixels 53, the control terminal of the active element 52 is connected to the vertical selection line 55 in row units, and the output terminal thereof is connected to the vertical signal line 56 in column units.

One end of the vertical selection line 55 is connected to a vertical scanning circuit 57.
Connected to the output end of each row. Vertical scanning circuit 57
Is constituted by a shift register or the like, and sequentially outputs a vertical scanning pulse φVm. One end of the vertical signal line 56 is M
It is connected to the input terminal of an operation switch 58 composed of an OS transistor. A capacitor 59 is connected between the output terminal of the operation switch 58 and the ground. The output terminal of the operation switch 58 is further connected to the input terminal of the buffer 60. An operation pulse φOP is applied to the gate electrode of the operation switch 58.

The output terminal of the buffer 60 is connected to two horizontal signal lines 62L and 62R via a horizontal selection switch 61. The gate electrode of the horizontal selection switch 61 is connected to the output terminal of each column of two horizontal scanning circuits 63L and 63R provided corresponding to the left and right divided regions 54L and 54R of the imaging region 54. Horizontal scanning circuit 63L, 63R
Is constituted by a shift register or the like, and sequentially outputs horizontal scanning pulses φHLn and φHRn.

The analog pixel signal led to the horizontal signal line 62L is directly sent to the A / D converter 65 via the output circuit 64L.
L and converted to a digital pixel signal. The analog pixel signal led to the horizontal signal line 62R is delayed by a delay time corresponding to the scanning time of the horizontal scanning circuit 63L by the delay circuit 66 via the output circuit 64R, and then supplied to the A / D converter 65R. It is converted to a digital pixel signal. These two digital pixel signals are supplied to a mixer 67.
Are alternately selected and mixed in the imaging area 5
All four lines are digital image signals that are successively arranged on the time axis.

The digital image signal is supplied to a light source 68, modulated into an optical output by the light source 68, and then transmitted to an external device (not shown) such as a disk device, a display device or a printing device at a high speed by an optical fiber 69. Transmitted. As the light source 68, the first and second light sources described above are used.
As in the case of the second embodiment, a semiconductor light source such as a semiconductor laser or a light emitting diode is used.

As described above, in the solid-state imaging device using the amplification type imaging device, the imaging region 54 of the amplification type imaging device is used.
Is divided into a plurality (in this example, two), and each divided region 54
By deriving two pixel signals corresponding to L and 54R, the time required for deriving all pixel signals can be shortened. An on-axis continuous image signal is generated, and this image signal is modulated into a light output by a light source 68 and transmitted at a high speed by an optical fiber 69. Therefore, an image signal obtained by imaging is transmitted to an external device. High speed transmission is possible.

In each of the above embodiments, the image pickup area 1
The case where 3, 34, 54 are divided into two in the left-right direction of the figure has been described. However, the present invention is not limited to this. For example, it is divided into three or more in the left-right direction of the figure, or Various division modes are conceivable, such as dividing into two in the horizontal direction and dividing into two in the horizontal direction.

In each of the above embodiments, the pixel signals of a plurality of systems output from the image sensor are A / D converted and then mixed by the mixers 20, 44 and 67.
If the D converter is capable of high-speed operation, as shown in FIG. 4, the pixel signals of a plurality of systems are mixed in the analog stage by the mixer 71 and then digitally converted by the A / D converter 72 capable of high-speed operation. It is also a function to adopt a configuration that makes it possible. According to this, since only one A / D converter is required, the circuit configuration can be simplified and the cost can be reduced.

[0031]

As described above, according to the present invention,
In a solid-state imaging device having a solid-state imaging device in which an imaging region is divided into a plurality of regions and outputting a plurality of systems of pixel signals corresponding to the divided regions, a plurality of systems of pixel signals output from the solid-state imaging device are mixed and a time axis is set. Since a continuous image signal was generated above, the generated image signal was modulated into an optical output, and transmitted to an external device using an optical fiber.
An image signal obtained by imaging can be transmitted to an external device at high speed.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of the present invention applied to a CCD image sensor.

FIG. 2 is a schematic configuration diagram showing a second embodiment of the present invention applied to a MOS type imaging device.

FIG. 3 is a schematic configuration diagram showing a third embodiment of the present invention applied to an amplification type imaging device.

FIG. 4 is a block diagram of a main part showing a modification of the present invention.

[Explanation of symbols]

11 Sensor unit 12 Vertical CCD 13, 34,
54 Imaging area 15L, 15R Horizontal CCD 16L, 16R Charge-voltage converter 18L, 18R, 42L, 42R, 65L, 65R, 7
1 A / D converter 19, 43, 66 Delay circuit 20, 44, 67, 7
2 Mixer 21, 45, 68 Light source 22, 46, 69 Optical fiber 33, 53 Pixel 35, 55 Vertical selection line 3
6,56 Vertical signal line 37,57 Vertical scanning circuit 38,61 Horizontal selection switch 39L, 39R, 62L, 62R Horizontal signal line 40L, 40R, 63L, 63R Horizontal scanning circuit

Claims (4)

[Claims] An image pickup area is divided into a plurality of sections, and a solid-state image sensor that outputs a plurality of pixel signals corresponding to each of the divided areas; A signal processing circuit that generates an image signal continuous on the axis, a light source that modulates an image signal output from the signal processing circuit into a light output, and an optical fiber that transmits the light output from the light source to an external device. A solid-state imaging device comprising: 2. The solid-state imaging device according to claim 1, wherein said light source is a semiconductor laser. 3. The solid-state imaging device according to claim 1, wherein said light source is a light emitting diode. 4. A solid-state imaging device having a solid-state imaging device that divides an imaging region into a plurality of regions and outputs a plurality of systems of pixel signals corresponding to each of the divided regions, wherein a plurality of systems of pixel signals output from the solid-state imaging device are provided. A transmission method for transmitting a plurality of pixel signals output from the solid-state imaging device to generate a continuous image signal on a time axis, modulating the generated image signal into an optical output, And transmitting the output signal of the solid-state imaging device to an external device using an optical fiber.