JPH03217057A - Solid state image sensor - Google Patents

Abstract

PURPOSE:To shorten image data reading time of various original by providing a branch charge transfer unit connected to the intermediate position of the unit in the transferring direction and branching part of charge to be transferred through the unit and sequentially serially transferring the charge. CONSTITUTION:A photoelectric converter 1 having a plurality of photodetectors 11-1n are disposed in one-dimensional manner for photoelectrically converting a reflected light from an object 6 upon reception by the photodetectors 11-1n, a change transfer unit 3 for sequentially transferring the charges corresponding to the units 11-1n to be photoelectrically converted by the converter 1, and a branch charge transfer unit 3 connected to the intermediate position of the unit 3 in the transferring direction for branching part of the charge to be transferred by the unit 3 and sequentially serially transferring it, are provided. For example, the unit 4 has a control gate for controlling the branch movement of the charge to the connecting part of the unit 3, and performs ON, OFF controls of the gate based on a branch control signal.

Description

[Detailed description of the invention] [Summary] Facsimile, digital PPC (Plain
Provided is a solid-state image sensor that can shorten the time required to read image data of various originals, regarding a solid-state image sensor used in applications such as PaperCopy, and in particular, a solid-state image sensor formed by one-dimensionally arranging pixels. A photoelectric conversion section is formed by arranging a plurality of light receiving sections in a one-dimensional manner, and receives reflected light from a subject at the plurality of light receiving sections and performs photoelectric conversion; A charge transfer unit that sequentially serially transfers charges corresponding to each light receiving unit, and a charge transfer unit connected to an intermediate position in the transfer direction of the charge transfer unit, branches part of the charges transferred by the charge transfer unit and sequentially transfers them serially. A branch charge transfer section is provided.

[Industrial application field]

The present invention is applicable to facsimile, digital PPC (Plai
The present invention relates to a solid-state image sensor used in applications such as n Paper Copy, and particularly relates to a solid-state image sensor formed by one-dimensionally arranging pixels.

In recent years, solid-state image sensors used as line sensors input information as one-dimensional image information, so when inputting image information of a two-dimensional object, it is necessary to move the original of the object or change the line sensor itself. Image information is input by moving .

When inputting two-dimensional image information of objects of different sizes, such as A-3, A-4, A-5, etc., such line sensors are formed in a size that fits the largest object. Ru. A line sensor formed of a number of solid-state image sensing devices suitable for this large size is required to input image information of objects of various sizes and to quickly process the input image information.

[Conventional technology]

Conventionally, there have been solid-state imaging devices of this type as shown in FIGS. 8 and 9. FIG. 8 shows a schematic configuration diagram of a conventional solid-state image sensor, and FIG. 9 shows an output waveform diagram of the conventional solid-state image sensor.

In each of the above figures, the conventional solid-state image sensor is formed by arranging a plurality of light receiving elements 11 to 1n in a one-dimensional manner corresponding to each pixel of the captured image.
a photoelectric conversion unit 1 that receives reflected light from and performs photoelectric conversion;
A transfer gate section 2 that controls the transfer of charges as image information generated by photoelectric conversion of the photoelectric conversion section 1, and serially transfers and outputs the charges of each image information transferred based on the control of the transfer gate section 2. The configuration includes a charge transfer section 3 and an amplifier 5 that amplifies the charge of each image information.

Next, the operation of the conventional solid-state image sensor based on the above configuration will be explained. First, the transfer gate section 2 is turned on for a certain period of time.
At the same time as being in the FF state, a predetermined voltage is applied to the element electrodes of all the light receiving elements 11 to 1n in the photoelectric conversion section 1, thereby forming potential wells in all of the light receiving elements 11 to 1n.

In this state, originals 6 of various sizes move on the photoelectric converter 1 in the direction of the arrow in FIG. Holes generated by the received reflected light are collected in the potential wells of each of the light receiving elements 11 to 1n.

Next, by turning on the transfer gate section 2 and forming a potential well in the charge transfer section 3, the charges collected in each of the light receiving elements 11 to 1n of the photoelectric conversion section 1 are transferred to the charge transfer section 3. Move to.

The charge transfer section 3 serially transfers the respective collected charges and outputs them to the amplifier 5. This amplifier 5 amplifies the charge serially transferred and outputted at a predetermined amplification factor, and outputs the charge from the output terminal D.
is o+Ned with the image information of the original 6 and output.

As shown in FIG. 9, this image information is based on the fact that the charges of the light receiving elements 11 to 16 are output from time t1 to t2, and the charges of the light receiving elements 17 to 1n (in reality, the photoelectric conversion output is zero). ) is output as data "none" between time t2 and t3.

[Problem to be solved by the invention]

Since conventional solid-state image sensors are configured as described above, all image information is serially transferred from a single output terminal, and when reading image data of a large-sized document, it is difficult to read the image data. The problem was that it took a long time to operate.

In addition, when reading a document smaller than the maximum size of the subject document, conventional solid-state image sensors also display "no image data" for areas where there is no image data outside of the small document portion.
data is serially transferred, which poses a problem in that the reading time required for the largest original size is required regardless of the size of the original.

The present invention has been made in order to solve the above-mentioned problems, and therefore, it is an object of the present invention to provide a solid-state imaging device that can shorten the time required to read image data of various types of originals.

[Means to solve the problem]

FIG. 1 shows a diagram explaining the principle of the present invention.

In the same figure, the present invention is formed by arranging a plurality of light receiving sections in a one-dimensional manner, and receives reflected light from a subject by the plurality of light receiving sections and converts the light into electricity, and the photoelectric conversion section A charge transfer unit that serially transfers each charge corresponding to each light receiving unit that has been photoelectrically converted, and a charge transfer unit that is connected to an intermediate position in the transfer direction of the charge transfer unit and branches a part of the charges transferred by the charge transfer unit. A branch charge transfer unit that performs serial transfer is provided.

[Effect]

In the present invention, by connecting the branch charge transfer section to a predetermined position of the charge transfer section, the image data of the document to be photographed can be branched and transferred in parallel, thereby shortening the reading time.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on FIGS. 2 to 4. This FIG. 2 is a plan view of the main part configuration of the solid-state image sensor of this embodiment, and FIG. 3 is a cross-sectional view taken along the line A-A in FIG.
FIG. 4 shows a sectional view taken along line BB in FIG. 2.

In each of the above figures, the solid-state image sensor according to this embodiment has light receiving elements 11 arranged one-dimensionally, as in the prior art described above.
A photoelectric conversion section 1, a transfer gate section 2, and a charge transfer section 3 each having a photoelectric conversion section 1n are provided in common, and the photoelectric conversion section 1 is located at an intermediate position of the charge transfer section 3 corresponding to the light receiving section 16 adjacent to the edge of the various types of originals 6 to be photographed. a branch charge transfer section 4 which branches part of the charge transferred by the charge transfer section 3 and sequentially transfers it serially; and a first branch charge transfer section 4 which amplifies each output of the charge transfer section 3 and the branch charge transfer section 4. This configuration additionally includes second amplifiers 5a and 5b.

Is the branch charge transfer section 4 connected to the charge transfer section 3? The control gate 41 is provided with a control gate 41 for controlling the branching movement of charges in a branching control signal φ.
The configuration is such that ON-OFF control is performed based on C, and a portion of each charge transferred by the charge transfer unit 3 is transferred in a branched manner.

Next, the operation of this embodiment based on the above configuration will be explained with reference to FIGS. 3 to 7.

First, the gate clock signal φTG (“
L'' level) is applied to form potential wells in each of the light receiving elements 11 to 1n of the photoelectric conversion unit 1 in the same manner as in the prior art.The original 6 is moved onto each of the light receiving elements 11 to 1n (as shown in FIG. ), and the reflected light from the original 6 is received by each of the light receiving elements 11 to 1n.The light receiving elements 11 to 1n collect the charge generated by the received reflected light from the original 6 into a potential well. , converts the image of the document 6 into an electrical signal corresponding to the image.

The transfer gate section 2 is turned on by the gate clock signal φ6 ("H" level), and a potential well is formed in the charge transfer section 3 and the branch charge transfer section 4 by the reset clock signals φ and φ2. , the charges collected in each of the light receiving elements 11 to 1n are transferred to the corresponding charge transfer section 3.

FIGS. 6A and 6B show control signal waveforms and output signal states when the charges transferred to the charge transfer section 3 are output to the first amplifier 5a without being branched. In the figure, a first reset clock signal φ1 (or auxiliary reset clock signal φ) and a second reset clock signal φ
2 is formed by a signal waveform that becomes "H" level and "L" level in a complementary manner, and is input to the charge transfer section 3 and branch charge transfer section 4. The branch control signal φ, which controls the branching of charges from the charge transfer unit 3 to the branch charge transfer unit 4, is formed with a signal waveform that continuously maintains the “L” level, and is formed by the control gate of the branch charge transfer unit 4. 41. The signal levels of the control signals manually input are sequentially changed from time t11 to time t13, etc., and the transfer electrodes 321a to 321a in the charge transfer unit 3 are
By sequentially moving each charge to 31nb in the direction of arrow C shown in FIG. 3, output signals 81 to S, (see FIG. 6(B)) are outputted from the output terminal D through the first amplifier 5a. Output.

On the other hand, the moving charges of the charge transfer section 3 are branched into the charge transfer section 4.
FIGS. 7(A) and 7(B) show each control signal waveform and output signal state when the signal is branched to and output. In the figure, the branch control signal φ goes to the "H" level at 1, 1, 1 at the same time as the rising edge C of the second reset clock signal φ2, and after the falling edge of the second reset clock signal φ2. Also “H”
Maintain level status 1 S1, 1:22
It becomes "L" level at 25 2g. Further, the auxiliary reset clock signal φ3 is set to 1 when the first reset clock signal φl rises.
, 1 , 21 2 after a predetermined time has elapsed after 1 o'clock
427 becomes "H" level, and simultaneously becomes "L" level at times t23, t26, and t29 when the first reset clock signal φ1 falls.

The branch control signal φ is input to the control C gate 41, and the auxiliary reset clock signal φ3 is input to the transfer electrodes 326a and 11 326b of the charge transfer unit 3, so that the transfer electrodes 321a to 217b of the charge transfer unit 3 are The charge is branched to the branch charge transfer section 4 via the control gate 4C in the direction of the arrow D shown in FIG.
6 to output So. Further, the charges in the transfer electrodes 326a to 31Ilb of the charge transfer unit 3 are transferred to the first amplification unit 5a.
Output signals 81 to S15 are outputted via the
).

In this way, by branching the image data that has deviated from the document 6 and transferring it to the branch charge transfer section 4, unnecessary image data can be branched, and the image data reading operation can be optimized according to the document size.

In the above embodiment, a single branch charge transfer section 4 is connected in the middle of the charge transfer section 3, and a part of the charge transferred by the charge transfer section 3 is branched to the branch charge transfer section 4. However, a configuration in which a plurality of branch charge transfer sections are connected can also be adopted. The plurality of branch charge transfer units are arranged to charge transfer units corresponding to the light receiving units at the edges of various sizes of the subject document, such as A-3, 12 A-4, A-5, B-4, and B-5. It will be connected.

Further, in each of the above embodiments, the branch charge transfer section is connected to a predetermined position in the middle of the charge transfer section corresponding to the light receiving section corresponding to the end of each size of the object, but the branch charge transfer section is not limited to the above positions. A branch charge transfer section may be provided at any intermediate position of the charge transfer section. In this case, the image information of a single document is branched into a plurality of parts and output as output signals, and the branched output signals are combined by a separately provided image processing means.

〔Effect of the invention〕

As explained above, in the present invention, by connecting a branch charge transfer section to a predetermined intermediate position of the charge transfer section, the image data of the subject document can be branched and transferred in parallel, and the reading time can be shortened. have an effect.

13

[Brief explanation of drawings]

Fig. 1 is a diagram explaining the principle of the present invention, Fig. 2 is a configuration diagram of an embodiment of the invention, Fig. 3 is a plan view of the main part configuration of the embodiment shown in Fig. 5 is a sectional view taken along line AA, FIG. 5 is a sectional view taken along line BB in FIG. 3, and FIGS. 6 (A) and (B) are each control signal waveform diagram of the non-branched output in the embodiment shown in FIG. 3. 7(A) and (B) are control signal waveform diagrams and output signal format diagrams of branch outputs in the embodiment shown in FIG. 3, and FIG. 8 is a configuration of a conventional solid-state image pickup device. 9A and 9B show output waveform diagrams of a conventional solid-state image sensor. 1... Photoelectric conversion section 2... Transfer gate section 3... Charge transfer section 4... Branch charge transfer section 5, 5a, 5b - (first and second) amplifier 14 6... Original 1 1 ~ 1 n... Light receiving element 3 1 nb ~ 3 2 1-a... Transfer electrode

Claims (1)

[Scope of Claims] 1. A photoelectric conversion section formed by arranging a plurality of light receiving sections in a one-dimensional manner, and receiving reflected light from a subject at the plurality of light receiving sections and photoelectrically converting the received light; and the photoelectric conversion section. A charge transfer section that sequentially and serially transfers each charge corresponding to each light receiving section that has been photoelectrically converted by the charge transfer section; A solid-state image sensing device comprising: a branch charge transfer unit that sequentially transfers charges serially. 2. The solid-state imaging device according to claim 1, wherein the branch charge transfer section is connected to a charge transfer section at an intermediate position in the transfer direction where charges are output from a light receiving section located near an end of the object. element.