Image pickup system with overlap and non-overlap exposure period
At least one image pickup system that acquires distance information and prevents missing, or loss of, information while taking countermeasures against flicker, includes a first image pickup apparatus, a second image pickup apparatus, and a signal processing unit configured to process signals acquired from the first image pickup apparatus and the second image pickup apparatus. An exposure period of the first image pickup apparatus and an exposure period of the second image pickup apparatus are repeated a plurality of times in one frame. The exposure period of the first image pickup apparatus is overlapped with a non-exposure period of the second image pickup apparatus, and a non-exposure period of the first image pickup apparatus is overlapped with the exposure period of the second image pickup apparatus.
1. An image pickup system, comprising:
a first image pickup apparatus;
a second image pickup apparatus; and
a signal processing unit configured to process signals acquired from the first image pickup apparatus and the second image pickup apparatus, wherein
an exposure period of the first image pickup apparatus is repeated a plurality of times for each pixel row in the one frame,
an exposure period of the second image pickup apparatus is repeated a plurality of times for each pixel row in the one frame,
the exposure period of the first image pickup apparatus is overlapped with a non-exposure period of the second image pickup apparatus, and a non-exposure period of the first image pickup apparatus is overlapped with the exposure period of the second image pickup apparatus, and
the signal processing unit acquires information of a distance to a subject, from the signals acquired from the first image pickup apparatus and the second image pickup apparatus.
2. The image pickup system according to claim 1 , wherein the exposure period of the first image pickup apparatus is different in length from the exposure period of the second image pickup apparatus.
3. The image pickup system according to claim 1 , wherein the exposure period of the first image pickup apparatus is overlapped with the exposure period of the second image pickup apparatus.
4. The image pickup system according to claim 1 , wherein the exposure period of the first image pickup apparatus is not overlapped with the exposure period of the second image pickup apparatus.
5. The image pickup system according to claim 1 , wherein the non-exposure period of the first image pickup apparatus is not overlapped with the non-exposure period of the second image pickup apparatus.
6. The image pickup system according to claim 1 , wherein the non-exposure period of the second image pickup apparatus corresponds to the exposure period of the first image pickup apparatus, and the non-exposure period of the first image pickup apparatus corresponds to the exposure period of the second image pickup apparatus.
7. The image pickup system according to claim 1 , wherein a first period in which the exposure period of the first image pickup apparatus is overlapped with the exposure period of the second image pickup apparatus is longer than a second period in which the non-exposure period of the first image pickup apparatus is overlapped with the exposure period of the second image pickup apparatus and a third period in which the non-exposure period of the second image pickup apparatus is overlapped with the exposure period of the first image pickup apparatus.
8. The image pickup system according to claim 1 , wherein the exposure period of the first image pickup apparatus corresponds to an opening period of a mechanical shutter included in the first image pickup apparatus, and the exposure period of the second image pickup apparatus corresponds to an opening period of a mechanical shutter included in the second image pickup apparatus.
9. The image pickup system according to claim 1 , wherein
each of the first image pickup apparatus and the second image pickup apparatus further includes a plurality of pixels two-dimensionally arranged, and
each of the plurality of pixels includes a photoelectric conversion portion and a charge holding portion configured to hold electric charges transferred from the photoelectric conversion portion.
10. The image pickup system according to claim 9 , wherein a start and an end of the exposure period of the first image pickup apparatus are performed collectively for the plurality of pixels.
11. The image pickup system according to claim 9 , wherein a start and an end of the exposure period of the second image pickup apparatus are performed collectively for the plurality of pixels included in the second image pickup apparatus.
12. The image pickup system according to claim 9 , wherein
the charge holding portion includes a first charge holding portion and a second charge holding portion,
each of the plurality of pixels includes a first transfer switch and a second transfer switch, the first transfer switch being configured to transfer electric charges from the photoelectric conversion portion to the first charge holding portion, and the second transfer switch being configured to transfer electric charges from the photoelectric conversion portion to the second charge holding portion, and
electric charges are transferred from the photoelectric conversion portion to the first charge holding portion a plurality of times in a first frame, and electric charges are transferred from the photoelectric conversion portion to the second charge holding portion a plurality of times in a second frame that is different from the first frame.
13. A moving body comprising:
the image pickup system according to claim 1 ;
a distance information acquiring unit configured to acquire information of a distance to an objective, from a parallax image based on the signals acquired from the first image pickup apparatus and the second image pickup apparatus; and
a control unit configured to control the moving body, based on the distance information.