Dome cover, image pickup apparatus, and image pickup system
A dome cover for covering a camera, the dome cover includes a spherical part and an aspherical part. The spherical part and the aspherical part have a boundary, where the spherical part and the aspherical part are adjacent to each other, on each of a front surface and a back surface of the dome cover. The aspherical part has a shape symmetrical with respect to a rotation around a rotation axis including a center of a sphere of the spherical part. On a section including the rotation axis, a distance from the rotation axis to the aspherical part increases as a position of the aspherical part becomes more distant from the boundary, an angle formed between the rotation axis and a line segment connecting the center of the sphere and the boundary on the front surface is less than 90°. A predetermined condition is satisfied.
1. A dome cover for covering a camera, the dome cover comprising:
a spherical part and an aspherical part,
wherein the spherical part and the aspherical part have a boundary, where the spherical part and the aspherical part are adjacent to each other, on each of a front surface and a back surface of the dome cover,
wherein the aspherical part has a shape symmetrical with respect to a rotation around a rotation axis including a center of a sphere of the spherical part,
wherein on a section including the rotation axis, a distance from the rotation axis to the aspherical part increases as a position of the aspherical part becomes more distant from the boundary, an angle formed between the rotation axis and a line segment connecting the center of the sphere and the boundary on the front surface is less than 90°, and
wherein a conditional expression
1.12 <|fm/fd|< 1.80
is satisfied where fd is a focal length of the spherical part, and fm is a focal length of the aspherical part.
2. The dome cover according to claim 1 , wherein on the section, each of the front surface and the back surface of the aspherical part has an arc shape.
3. The dome cover according to claim 1 , wherein at the boundary, a tangential plane is common to the spherical part and the aspherical part.
4. The dome cover according to claim 1 , wherein a center of a sphere of the front surface and a center of a sphere of the back surface of the spherical part are disposed on the rotation axis.
5. The dome cover according to claim 1 , wherein the rotation axis is common to the front surface and the back surface of the aspherical part.
6. The dome cover according to claim 1 , wherein a material of the dome cover includes a thermoplastic resin.
7. A dome cover for covering a camera, the dome cover comprising:
a spherical part and an aspherical part,
wherein the spherical part and the aspherical part have a boundary, where the spherical part and the aspherical part are adjacent to each other, on each of a front surface and a back surface of the dome cover,
wherein the aspherical part has a shape symmetrical with respect to a rotation around a rotation axis including a center of a sphere of the spherical part,
wherein on a section including the rotation axis, a distance from the rotation axis to the aspherical part increases as a position of the aspherical part becomes more distant from the boundary, an angle formed between the rotation axis and a line segment connecting the center of the sphere and the boundary on the front surface is less than 90°, and
wherein a conditional expression
0.00<θ r2 −θ r1 <1.00
is satisfied where θ r1 (°) is an angle formed between the line segment and a plane orthogonal to the rotation axis, and θ r2 (°) is an angle formed between the plane and a line segment connecting the center of the sphere and the boundary on the back surface.
8. The dome cover according to claim 7 , wherein at the boundary, a tangential plane is common to the spherical part and the aspherical part.
9. The dome cover according to claim 7 , wherein a center of a sphere of the front surface and a center of a sphere of the back surface of the spherical part are disposed on the rotation axis.
10. The dome cover according to claim 7 , wherein the rotation axis is common to the front surface and the back surface of the aspherical part.
11. The dome cover according to claim 7 , wherein a material of the dome cover includes a thermoplastic resin.
12. The dome cover according to claim 7 , wherein on the section, each of the front surface and the back surface of the aspherical part has an arc shape, and
wherein a conditional expression
0.40 <|fm/fd|< 1.80
is satisfied where fd is a focal length of the spherical part, and fm is a focal length of the aspherical part.
13. An image pickup apparatus comprising:
the dome cover according to claim 1 ; and
a camera covered with the dome cover.
14. The image pickup apparatus according to claim 13 , further comprising a driving device configured to rotate the camera,
wherein a rotation center of the camera is located on the rotation axis.
15. An image pickup system comprising:
the image pickup apparatus according to claim 13 ; and
a controller configured to perform a control of the image pickup apparatus.
16. The image pickup system according to claim 15 , wherein the controller includes a transmitter configured to transmit a control signal for controlling the image pickup apparatus.
17. The image pickup system according to claim 15 , wherein the controller includes an operation unit configured to operate the image pickup apparatus.
18. The image pickup system according to claim 15 , further comprising a display configured to display information on the control.
19. An image pickup apparatus comprising:
the dome cover according to claim 7 ; and
a camera covered with the dome cover.
20. An image pickup system comprising:
the image pickup apparatus according to claim 19 ; and
a controller configured to perform a control of the image pickup apparatus.