JPS6194466A - Solid-state image pickup element - Google Patents

Abstract

PURPOSE:To control the quantity of the maximum signal charge at the time of transfer to a horizontal transferring section by providing an overflow drain having a gate near the horizontal transferring section and opposite side of a photoelectric converting section. CONSTITUTION:An overflow drain 6 is provided at the opposite side of the vertical transferring section 2 of the horizontal transferring section 3 corresponding to each transferring section 2, and a gate 7 is formed on the drain. Light incident on a photoelectric converting section 1 is read out in the transferring section 2 according to the quantity of light, and the quantity of signal charges of the transferring section is transferred to the transferring section 3 successively in unit of row. Such operation is applied to all the quantity of signal charges transferred from the transferring section 2 to the transferring section 3 and a voltage applied to the gate 7 is changed. By this way, the quantity of the maximum output signal charge from a solid-state image pickup element can be controlled to a level common to all picture elements.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention can be used, for example, in a telephoto camera device,
The present invention relates to a solid-state image sensor including at least a photoelectric conversion section, a horizontal transfer section, and a signal output section.

``Prior Art'' Conventionally, in this type of solid-state imaging device, photoelectric conversion units 1 are arranged vertically in the figure as shown in FIG. Vertical transfer section 2 in parallel
are formed respectively, and a horizontal transfer section 3 is formed close to each end of the vertical transfer section 2, one end of which is connected to a signal output section 5.
It is said that

This is an interline transfer method, in which signal charges are formed according to the amount of light incident on the photoelectric conversion section 1, and are read out to the vertical transfer section 2 via a transfer gate (not shown). The entire charge pattern of the vertical transfer section 2 is transferred row by row to the horizontal transfer section 3 and outputted from the signal output section 5 as a video signal.

FIG. 5 shows a conventional solid-state image sensor using a frame transfer method. Photoelectric conversion unit 1 in which a plurality of photoelectric conversion elements are arranged
A storage section 4 is extended and formed at one end of each storage section 4, and a horizontal transfer section 3 is commonly provided adjacent to the other end of each storage section 4. The signal charge generated in the photoelectric conversion unit 1 is transferred to the storage unit 4 within the vertical flank period, and the entire charge pattern in the storage unit 4 is transferred row by row to the horizontal transfer unit 3 for each horizontal scanning line, and the signal charge is output. The signal is outputted from section 5 as a video signal.

Solid-state image sensors have lower noise and less afterimage compared to image pickup tubes.

It is excellent in terms of burn-in, etc., and phenomena such as flue mink and smear caused by excess charge peculiar to solid-state image sensors are now being suppressed or eliminated.

``Problems to be Solved by the Invention'' However, since it is difficult to control the maximum output charge amount with conventional solid-state image sensors, when used as a telephoto camera device, clamp circuits, white clip d-paths, etc. The drawback is that a complicated and expensive circuit must be installed on the television camera device side.

An object of the present invention is to provide an overflow drain having at least one or more gates adjacent to the horizontal transfer section of a solid-state image sensor on the opposite side from the vertical transfer section, and to transfer the vertical transfer by changing the voltage applied to each gate. An object of the present invention is to provide a solid-state image sensor that can control the maximum amount of signal charge when transferred from a horizontal transfer section to a horizontal transfer section.

"Means for Solving the Problem" According to the present invention, in a solid-state imaging device comprising a photoelectric conversion section, a vertical transfer section, a horizontal transfer section, and a signal output section, a vertical transfer section is provided adjacent to the horizontal transfer section. An overflow drain having at least one gate is provided on the opposite side, and the maximum output signal charge amount can be controlled by the voltage applied to each case.

"Example" Next, embodiments of the present invention will be described in detail with reference to the drawings.

1 to 3 show embodiments of the present invention, in which the present invention is applied to a solid-state image sensor using an interline transfer method.

As shown in FIG. 1, similar to FIG. 4, the photoelectric conversion sections 1 are arranged, and the vertical transfer sections 2 adjacent thereto. A common horizontal transfer section 3 is provided with a signal output section 5 close to one end of the vertical transfer section 2.

In this embodiment, an overflow drain 6 is provided on the opposite side of the horizontal transfer section 3 from the vertical transfer section 2 in correspondence with each vertical transfer section 2, and a single gate 7 extends commonly over these overflow trains 6. It is formed. The side of the overflow drain 6 opposite to the horizontal transfer section 3 with respect to the gate 7 is connected to each other.

The light incident on the photoelectric conversion section l is read out to the vertical transfer section 2 via a transfer gate (not shown) according to the amount of light, and the signal charge amount of the vertical transfer section 2 is sequentially transferred row by row to the horizontal transfer section 3. be transferred. When each signal charge amount is shifted from the vertical transfer section 2 to the horizontal transfer section 3, by applying a voltage to the gate 7 of the overflow drain 6, the gate 7
is turned ON, and the unstable signal charge amount is removed through the overflow drain 6 installed adjacently. By performing such an operation on the amount of signal charge transferred from all the vertical transfer sections 2 to the horizontal transfer section 3, the maximum output signal from the solid-state image sensor can be adjusted by changing the voltage applied to the case 1-7. The amount of charge can be controlled to a level common to all pixels.

FIG. 2 shows a second embodiment of the invention. As shown in FIG. 6, on the photoelectric conversion section 1 in FIG. are provided alternately and repeatedly,
Color filters of the same red or blue color are provided in the column direction. Further, as shown in FIG. 2, gates 7 and 8 are provided alternately for every other overflow drain 6, the gates 7 are connected to each other by a wiring 10, and the gates 8 are connected to each other by another wiring 10. Connected.

The operation of this embodiment is basically the same as that of the embodiment shown in FIG. It can be controlled.

FIG. 3 shows a third embodiment of the invention. As shown in FIG. 7, on the photoelectric conversion unit 1 in FIG.
and the color filter G for the green signal are sequentially and alternately repeated.
Red for column direction.

A color filter of the same color as blue or border color shall be used. Overflow train 6 as shown in Figure 3
The 3-hedral gates 7.8.9 connected to every other 2 gates are sequentially
Arrange the books one by one. The operation of this embodiment is also similar to that of the first embodiment, and by changing the voltage applied to each gate, the maximum output signal charge amount of the red signal, blue signal, and green signal from the solid-state image sensor can be controlled. In this embodiment, even if the color filters for red, blue, and green signals are mosaic-like, by applying pulse voltages to each gate 7, 8, and 9, the red signal from the solid-state image sensor, The maximum output signal charge amount of the blue signal and green signal can be controlled respectively.

The present invention can be similarly applied to the solid-state imaging device using the frame transfer method shown in FIG.

"Effects of the Invention" As explained above, the present invention makes it possible to control the maximum output charge amount by configuring a conventional solid-state image sensor with an overflow drain having at least one gate, and is suitable for small-sized television camera devices. This has the effect of making it unnecessary to display the white clip circuit or clamp circuit on the camera side.

[Brief explanation of the drawing]

1 to 3 each show an embodiment of the present invention, FIG. 4 shows a conventional interline type solid-state image pickup device, and FIG. 5 shows a conventional frame transfer type solid-state image pickup device. 6 and 7 are diagrams each showing the configuration of a color filter. 1: Photoelectric conversion section, 2: Vertical transfer section, 3: Horizontal transfer section, 4
: Storage section, 5: Signal output section, 6: Overflow drain, 7, 8.9: Gate, 10: Aluminum wiring, R: Red filter, G: Green filter, B: Blue filter.

Claims (1)

[Claims] (1) In a solid-state imaging device consisting of a photoelectric conversion section consisting of a plurality of photoelectric conversion elements, a horizontal transfer section, and a signal output section, at least one photoelectric conversion section is provided adjacent to the horizontal transfer section on the opposite side from the photoelectric conversion section. A solid-state imaging device that is provided with an overflow drain having the gate as described above, and can control the maximum output signal charge amount from each photoelectric conversion element by controlling the voltage applied to the gate.