Image sensor and method of driving the same
View Patent ↗An image sensor is provided. An image sensor can include a plurality of unit pixels. Each of the unit pixels can include a photoelectric converter as a light receiving element. In each unit pixel, a transport switching unit can transport charges in the photoelectric converter to a floating diffusion region, and a first switching unit can selectively connect the floating diffusion region to a first sensing line. A second switching unit can selectively connect the floating diffusion region to a second sensing line, and a first sensing part can be connected to the first sensing line, and a second sensing part can be connected to the second sensing line.
1. An image sensor including a plurality of unit pixels, each of the unit pixels comprising:
a photoelectric converter as a light receiving element;
a transport switching unit transporting charges in the photoelectric converter to a floating diffusion region;
a first switching unit selectively connecting the floating diffusion region to a first sensing line;
a second switching unit selectively connecting the floating diffusion region to a second sensing line;
a first sensing part connected to the first sensing line and converting a photo-electrically converted analog signal, stored in the floating diffusion region, to a digital signal on the basis of a first offset value; and
a second sensing part connected to the second sensing line and converting a photo electrically converted analog signal, stored in the floating diffusion region, to a digital signal on the basis of a second offset value;
wherein the first sensing part and the second sensing part perform data processing on charge information obtained from a first row of pixels during a first integration period and a second row of pixels during a second integration period at a predetermined timing, and the first and second rows of pixels have different exposure times.
2. The image sensor according to claim 1 , wherein there is a delay by a preset time between a time when the charge information is obtained from the first row of pixels, and a time when the charge information is obtained from the second row of pixels, in the image sensor.
3. The image sensor according to claim 1 , wherein there is a delay by a data processing time of the first sensing part and the second sensing part between a time when the charge information is obtained from the first row of pixels, and a time when the charge information is obtained from a row of pixels adjacent to the first row of pixels, in the image sensor.
4. The image sensor according to claim 1 , wherein the transport switching unit comprises one or more transistors connected to the photoelectric converter.
5. The image sensor according to claim 1 , wherein the floating diffusion region is connected to the transport switching unit.
6. The image sensor according to claim 1 , further comprising a reset switching unit.
7. The image sensor according to claim 1 , wherein the reset switching unit comprises one or more transistors connected to the floating diffusion region, and the reset switching unit is configured to remove charges from the photoelectric converter.
8. The image sensor according to claim 1 , further comprising a drive switching unit.
9. The image sensor according to claim 1 , wherein the drive switching unit comprises one or more transistors connected to the floating diffusion region, and the drive switching unit is configured to produce a signal having charge information by amplifying charges stored in the floating diffusion region.
10. The image sensor according to claim 8 , wherein the first and second switching units are connected to the drive switching unit.
11. An image sensor comprising:
a photoelectric converter as a light receiving element;
a transport switching unit transporting charges in the photoelectric converter to a floating diffusion region;
a first switching unit selectively connecting the floating diffusion region to a first sensing line;
a second switching unit selectively connecting the floating diffusion region to a second sensing line;
a first sensing part connected to the first sensing line and converting a photo-electrically converted analog signal, stored in the floating diffusion region, to a digital signal on the basis of an offset value; and
a second sensing part connected to the second sensing line and converting a photo-electrically converted analog signal, stored in the floating diffusion region, to a digital signal on the basis of an offset value;
wherein the image sensor is configured such that, in a first timing, for detecting charges overflowed from the photoelectric converter, first charge information of the floating diffusion region is transported to the first sensing line and the first sensing part, due to operation of the first switching unit; and
wherein the image sensor is configured such that, in a second timing, the transport switching unit is operated, charges stored in the photoelectric converter are transported to the floating diffusion region, and second charge information in the floating diffusion region is transported to the second sensing line and the second sensing part due to operation of the second switching unit.
12. The image sensor according to claim 11 , wherein, in the first timing, the transportation of the first charge information of the floating diffusion region to the first sensing line and the first sensing part, is performed in a state where the transport switching unit is turned off.
13. The image sensor according to claim 11 , wherein the transport switching unit comprises one or more transistors connected to the photoelectric converter.
14. The image sensor according to claim 11 , wherein the floating diffusion region is connected to the transport switching unit.
15. The image sensor according to claim 11 , further comprising a reset switching unit.
16. The image sensor according to claim 15 , wherein the reset switching unit comprise one or more transistors connected to the floating diffusion region, the reset switching unit is configured to remove charges from the photoelectric converter.
17. The image sensor according to claim 11 , further comprising a drive switching unit.
18. The image sensor according to claim 17 , wherein the drive switching unit comprises one or more transistors connected to the floating diffusion region, and the drive switching unit is configured to produce a signal having charge information by amplifying charges stored in the floating diffusion region.
19. A method of driving an image sensor, the image sensor comprising:
a transport switching unit transporting charges in the photoelectric converter to a floating diffusion region;
a first switching unit selectively connecting the floating diffusion region to a first sensing line;
a second switching unit selectively connecting the floating diffusion region to a second sensing line;
a first sensing part connected to the first sensing line and converting a photo-electrically converted analog signal, stored in the floating diffusion region, to a digital signal on the basis of an offset value; and
a second sensing part connected to the second sensing line and converting a photo-electrically converted analog signal, stored in the floating diffusion region, to a digital signal on the basis of an offset value;
wherein the method comprises:
in a first timing, operating the first switching unit to transport first charge information of the floating diffusion region to the first sensing line and the first sensing part;
in a second timing, operating the transport switching unit to transport charges stored in the photoelectric converter to the floating diffusion region; and
in the second timing, operating the second switching unit to transport second charge information from the floating diffusion region to the second sensing line and the second sensing part.