Imaging device that generates multiple-exposure image data
An imaging device includes a unit pixel cell. The unit pixel cell captures first data in a first exposure period and captures second data in a second exposure period different from the first exposure period, the first exposure period and the second exposure period being included in a frame period. A sensitivity per unit time of the unit pixel cell in the first exposure period is different from a sensitivity per unit time of the unit pixel cell in the second exposure period. The imaging device outputs multiple-exposure image data including at least the first data and the second data.
1. An imaging device comprising a unit pixel cell that includes a photoelectric converter including a first electrode, a second electrode, and a photoelectric conversion film between the first electrode and the second electrode, the photoelectric converter generating signal charge through photoelectric conversion, wherein
the unit pixel cell captures first data in a first exposure period and captures second data in a second exposure period different from the first exposure period, the first exposure period and the second exposure period being included in a frame period,
a potential difference between the first electrode and the second electrode in the first exposure period is different from a potential difference between the first electrode and the second electrode in the second exposure period, and
the imaging device generates multiple-exposure image data including at least the first data and the second data.
2. The imaging device according to claim 1 , wherein
the unit pixel cell includes
a signal detection circuit electrically connected to the second electrode, the signal detection circuit detecting the signal charge.
3. The imaging device according to claim 1 , further comprising a voltage control circuit that supplies a first voltage to the first electrode in the first exposure period and supplies a second voltage to the first electrode in the second exposure period, the first voltage being different from the second voltage.
4. The imaging device according to claim 3 , wherein
the unit pixel cell includes a signal detection circuit electrically connected to the second electrode, the signal detection circuit detecting the signal charge, and
the voltage control circuit supplies a third voltage to the first electrode in a non-exposure period provided between the first exposure period and the second exposure period such that the signal detection circuit does not detect the signal charge.
5. The imaging device according to claim 3 , wherein a length of the first exposure period is the same as a length of the second exposure period.
6. The imaging device according to claim 3 , wherein
the unit pixel cell captures, in the frame period, a plurality of data in a plurality of exposure periods including the first and second exposure periods, the plurality of exposure periods being different from each other, and
a potential difference between the first electrode and the second electrode in an earlier exposure period among the plurality of exposure periods is less than a potential difference between the first electrode and the second electrode in a later exposure period among the plurality of exposure periods.
7. The imaging device according to claim 3 , further comprising a signal processing circuit that extracts, from the multiple-exposure image data, a first subject image based on the first data and a second subject image based on the second data, the first subject image and the second subject image corresponding to a moving subject.
8. The imaging device according to claim 7 , wherein the imaging device outputs at least one of first image data and second image data, the first image data including the first subject image and not including the second subject image, the second image data including the second subject image and not including the first subject image.
9. The imaging device according to claim 1 , wherein a length of the first exposure period is the same as a length of the second exposure period.
10. The imaging device according to claim 1 , wherein
the unit pixel cell captures, in the frame period, a plurality of data in a plurality of exposure periods including the first and second exposure periods, the plurality of exposure periods being different from each other, and
a potential difference between the first electrode and the second electrode in an earlier exposure period among the plurality of exposure periods is greater than a potential difference between the first electrode and the second electrode in a later exposure period among the plurality of exposure periods.
11. The imaging device according to claim 1 , wherein
the unit pixel cell captures, in the frame period, a plurality of data in a plurality of exposure periods including the first and second exposure periods, the plurality of exposure periods being different from each other, and
a potential difference between the first electrode and the second electrode in an earlier exposure period among the plurality of exposure periods is less than a potential difference between the first electrode and the second electrode in a later exposure period among the plurality of exposure periods.
12. The imaging device according to claim 1 , further comprising a signal processing circuit that extracts, from the multiple-exposure image data, a first subject image based on the first data and a second subject image based on the second data, the first subject image and the second subject image corresponding to a moving subject.
13. The imaging device according to claim 12 , wherein brightness of the first subject image is different from brightness of the second subject image.
14. The imaging device according to claim 13 , wherein the signal processing circuit performs a process for correcting, on the basis of the first subject image and the second subject image, brightness of the first subject image and the second subject image in the multiple-exposure image data to be same.
15. The imaging device according to claim 12 , wherein a color of the first subject image is different from a color of the second subject image.
16. The imaging device according to claim 15 , wherein the signal processing circuit performs a process for correcting, on the basis of the first subject image and the second subject image, colors of the first subject image and the second subject image in the multiple-exposure image data to be same.
17. The imaging device according to claim 12 , wherein the signal processing circuit performs a process for adding, on the basis of the first subject image and the second subject image, an indicator indicating a temporal transition to each of the first subject image and the second subject image in the multiple-exposure image data.
18. The imaging device according to claim 3 , wherein
the unit pixel cell captures, in the frame period, a plurality of data in a plurality of exposure periods including the first and second exposure periods, the plurality of exposure periods being different from each other, and
a potential difference between the first electrode and the second electrode in an earlier exposure period among the plurality of exposure periods is greater than a potential difference between the first electrode and the second electrode in a later exposure period among the plurality of exposure periods.
19. The imaging device according to claim 1 , wherein a plurality of exposures that include the first exposure and the second exposure and a single reading of data that includes the first data and the second data are performed in the frame period.
20. The imaging device according to claim 1 , wherein the first data and the second data are read out from the unit pixel cell together.
21. The imaging device according to claim 1 , wherein a sensitivity per unit time of the unit pixel cell in the first exposure period is different from a sensitivity per unit time of the unit pixel cell in the second exposure period.