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CN-121986499-A - Solid-state imaging element, range image imaging device, and control method

CN121986499ACN 121986499 ACN121986499 ACN 121986499ACN-121986499-A

Abstract

The solid-state imaging device includes a plurality of pixels, an adder switch, and a pixel driving circuit. The plurality of pixels each have a photoelectric conversion element that generates electric charges corresponding to incident light, a charge storage unit that stores the electric charges, and a reset switch that resets the charge storage unit to a predetermined reset potential supplied from a power supply line. The adder switch is connected in series with 2 or more stages between a connection line connecting the power supply line side of the reset switches of a predetermined number of pixels and the power supply line. The addition switch is capable of changing the region of the pixel to which the electric charges stored in the electric charge storage unit are added by changing the on state. The pixel driving circuit changes the on states of the reset switch and the addition switch of the 2-stage or more according to the region of the pixel to which the addition is performed.

Inventors

  • ISOBE KEIGO

Assignees

  • 凸版控股株式会社

Dates

Publication Date
20260505
Application Date
20241002
Priority Date
20231013

Claims (9)

  1. 1. A solid-state imaging element is provided with: A plurality of pixels each having a photoelectric conversion element that generates electric charges corresponding to incident light, a charge storage unit that stores the electric charges, and a reset switch that resets the charge storage unit to a predetermined reset potential supplied from a power supply line; An addition switch connected in series between a connection line connecting the power supply line side of the reset switch of a predetermined number of pixels and the power supply line for at least 2 stages, capable of changing a region of the pixels in which the charges stored in the charge storage unit are added by changing a conduction state, and And a pixel driving circuit for changing the on states of the reset switch and the addition switch of the 2-stage or more according to the region of the pixel to be added.
  2. 2. The solid-state imaging element according to claim 1, wherein, The adding switch above the 2 stages is as follows: A first addition switch arranged between a first connection line connecting the power supply line sides of the reset switches of N pixels and the power supply line, and configured to be capable of adding the charges stored in the N charge storage units via the first connection line and the reset switch, wherein N is an integer of 2 or more, and A second addition switch disposed between a second connection line connecting the power supply lines of the M first addition switches and the power supply lines, and configured to be capable of adding addition charges of an addition pixel region, which is a region of the N pixels connected by the first connection line, via the second connection line and the first addition switch, wherein M is an integer of 2 or more, The pixel driving circuit changes the on states of the reset switch, the first addition switch, and the second addition switch according to the region of the pixel to which the addition is performed.
  3. 3. The solid-state imaging element according to claim 2, wherein, The addition pixel regions are connected in a linear manner and function as a linear sensor.
  4. 4. The solid-state imaging element according to claim 2, wherein, The first connection line and the second connection line are connected in such a manner that non-adjacent pixels are added to each other.
  5. 5. The solid-state imaging element according to any one of claims 1 to 4, wherein, The pixel is a 4-transistor pixel, and the 4-transistor pixel includes a reset transistor serving as the reset switch, a source follower transistor that converts the charge into an electric signal, a transfer transistor that transfers the charge to the source follower transistor, and a selection transistor that selects readout of the electric signal of the pixel.
  6. 6. The solid-state imaging element according to any one of claims 1 to 4, wherein, The pixel is a 3-transistor pixel, which is provided with a reset transistor as the reset switch, a source follower transistor that converts the charge into an electric signal, and a selection transistor that selects the electric signal readout of the pixel.
  7. 7. The solid-state imaging element according to any one of claims 1 to 4, wherein, The pixel includes a plurality of charge accumulating sections, each of which is capable of distributing and accumulating a charge, The pixel driving circuit causes the electric charges to be distributed to and accumulated in each of the electric charge accumulating portions.
  8. 8. A range image capturing device is provided with: A light source unit that irradiates an object with a light pulse; A light receiving unit having the solid-state imaging device according to claim 7, and And a distance image processing unit that controls the pixel driving circuit to store electric charges in the electric charge storage units, and calculates a distance to the subject based on the electric charges stored in the electric charge storage units.
  9. 9. A control method is a control method of a solid-state imaging element, The solid-state imaging element is provided with: A plurality of pixels each having a photoelectric conversion element generating a charge corresponding to incident light, a charge storage unit storing the charge, and a reset switch resetting the charge storage unit to a predetermined reset potential supplied from a power supply line, and An addition switch in which a connection line connecting the power supply lines of the reset switches of a predetermined number of pixels is connected in series with the power supply lines at least 2 stages, and the area of the pixels in which the charges stored in the charge storage unit are added can be changed by changing the on state, The pixel driving circuit changes the on states of the reset switch and the addition switch of the 2-stage or more according to the region of the pixel to which the addition is performed.

Description

Solid-state imaging element, range image imaging device, and control method Technical Field The invention relates to a solid-state imaging element, a range image imaging device, and a control method. The present application claims priority based on japanese patent application No. 2023-177274 of the application of japan, 10/13 of 2023, the contents of which are incorporated herein by reference. Background A range image capturing apparatus of a Time of Flight (hereinafter referred to as "TOF") system has been realized that measures the distance between a measuring instrument and an object based on the Time of Flight of light in a space (measurement space) by using the fact that the speed of light is known (for example, refer to patent document 1). In an imaging device such as a range image imaging device, for example, imaging is performed using a solid-state imaging element including a photoelectric conversion element such as a photodiode. Prior art literature Patent literature Patent document 1 Japanese patent No. 4235729 Disclosure of Invention Problems to be solved by the invention However, pixels of the solid-state imaging element may be used in addition. In a conventional solid-state imaging device, a plurality of switches are provided in a pixel, and pixel values (charges) obtained by photoelectrically converting a plurality of photoelectric conversion elements are added to each other for use. Therefore, the conventional solid-state imaging device has a problem that the pixel size increases. In addition, in the conventional solid-state imaging device, it is difficult to flexibly change the pixel region in which charges are added according to the imaging scene. The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a solid-state imaging device, a range image imaging apparatus, and a control method, which can flexibly change a pixel region in which charges are added according to an imaging scene while suppressing an increase in pixel size. Means for solving the problems In order to solve the above-described problems, embodiment 1 of the present invention relates to a solid-state imaging device including a plurality of pixels each including a photoelectric conversion element that generates electric charges corresponding to incident light, a charge storage unit that stores the electric charges, and a reset switch that resets the charge storage unit to a predetermined reset potential supplied from a power line, an addition switch that is connected in series between a connection line that connects the power line side of the reset switch of a predetermined number of pixels and the power line by 2 or more stages, and that can change a region of the pixels in which the electric charges stored in the charge storage unit are added by changing an on state, and a pixel driving circuit that changes an on state of the reset switch and the addition switch of 2 or more stages according to the region of the pixels in which the addition is performed. In the solid-state imaging device according to aspect 2 of the present invention, the 2-stage or higher addition switch may be a first addition switch disposed between a first connection line connecting the power supply line sides of the N pixels to the power supply line, and may be a state in which the charges accumulated in the N charge accumulating portions can be added via the first connection line and the reset switch, wherein N is an integer of 2 or more, and a second addition switch disposed between a second connection line connecting the power supply line sides of the M first addition switches to the power supply line, and may be a state in which the added charges of the N pixels connected by the first connection line, that is, an added pixel region, can be added via the second connection line and the first addition switch, wherein M is an integer of 2 or more, and the pixel driving circuit may change the added pixel region, the reset switch, and the first addition switch, and the second addition switch on state according to the region of the pixel to which the addition is performed. In addition, in the solid-state imaging device according to embodiment 2, the additional pixel regions may be connected in a linear manner and function as a linear sensor. In addition, in the solid-state imaging device according to aspect 2, the first connection line and the second connection line may be connected so as to add pixels that are not adjacent to each other. In addition, in the solid-state imaging device according to any one of aspects 1 to 4, the pixel may be a 4-transistor pixel, and the 4-transistor pixel may include a reset transistor as the reset switch, a source follower transistor that converts the charge into an electric signal, a transfer transistor that transfers the charge to the source follower transistor, and a selection transistor that selects readout of the electric signal of the pixel. In