Multi-camera panoramic image capture devices with a faceted dome
A low parallax imaging device includes a dome defining an interior volume in which a plurality of imaging lens elements are disposed. The dome includes a first outer optical element associated with a first of the imaging lens elements and a second outer optical element associated with a second of the imaging lens elements. Facets are provided at seams in the dome between the first outer optical element and the second outer optical element.
1. An imaging device, comprising:
a dome defining at least a portion of an interior volume, the dome comprising:
a first transparent lens element comprising a plurality of first edges forming a first polygonal shape,
a second transparent lens element comprising a plurality of second edges forming a second polygonal shape, wherein a second edge of the plurality of second edges abuts a first edge of the plurality of first edges of the first transparent lens element at a seam, and
a groove extending along the seam between the first transparent lens element and the second transparent lens element,
a first imaging lens comprising a first plurality of optical elements;
a first housing coupled to the first imaging lens and including a first mounting feature;
a second imaging lens comprising a second plurality of optical elements; and
a second housing coupled to the second imaging lens and including a second mounting feature,
wherein at least one of:
the first mounting feature cooperates with the groove to retain the first imaging lens in the interior volume to direct image light passing through the first transparent lens element to a first image plane, or
the second mounting feature cooperates with the groove to retain the second imaging lens in the interior volume to direct image light passing through the second transparent lens element to a second image plane.
2. The imaging device of claim 1 , wherein:
the seam comprises a gap between a first side of the plurality of first sides and a second side of the plurality of second sides.
3. The imaging device of claim 1 , wherein:
the dome further comprises a notch disposed in the groove; and
one of the first mounting protrusion or the second mounting protrusion is received in the notch.
4. The imaging device of claim 1 , wherein at least one of the first mounting projection or the second mounting projection comprise one or more mounting posts configured to be received in the groove.
5. The imaging device of claim 1 , further comprising a frame disposed in the interior volume, wherein the first lens housing and the second lens housing are coupled to the frame.
6. The imaging device of claim 5 , wherein the frame has a polygonal shape that nominally matches a polygonal shape of the imaging device.
7. The imaging device of claim 1 , wherein the groove is formed in an interior surface of the dome at the seam.
8. The imaging device of claim 1 , wherein the groove comprises a first facet and a second facet, the first facet directs a first portion of incident light entering the dome at the seam to the first imaging lens, and the second facet directs a second portion of the incident light entering the dome at the seam to the second imaging lens.
9. The imaging device of claim 8 , wherein the first facet comprises a first angled surface extending away from the seam toward the first transparent lens element and the second facet comprises a second angled surface extending away from the seam toward the second transparent lens element.
10. The imaging device of claim 9 , the dome further comprising:
a first mirrored surface configured to reflect image light directed by the first angled surface, wherein the first mirrored surface reflects image light to the first imaging lens; and
a second mirrored surface configured to reflect image light directed by the second angled surface, wherein the second mirrored surface reflects light to the second imaging lens.
11. The imaging device of claim 8 , wherein at least one of the first facet or the second facet directs light by total internal reflection.
12. The imaging device of claim 11 , further comprising a compensator that equalizes an optical path length for light directed by at least one of the first facet or the second facet.
13. The imaging device of claim 1 wherein:
the first imaging lens provides a first field of view comprising a first nominal field of view and a first extended field of view larger than the first nominal field of view,
the second imaging lens provides a second field of view comprising a second nominal field of view and a second extended field of view larger than the second nominal field of view;
the first extended field of view and the second extended field of view overlap at the seam; and
the first housing and the second housing configure the first imaging lens and the second imaging lens to reduce the overlap to two pixels or less.
14. The imaging device of claim 1 , wherein:
first projections of paraxial chief rays included in the incident light that enters the first lens element converge to an entrance pupil located behind the first image plane;
second projections of non-paraxial chief rays included in the incident light that enter the first lens element converge to a low parallax point, and
the first housing is coupled to the dome to reduce a distance between the entrance pupil and the low parallax point.
15. The imaging device of claim 1 , wherein the first imaging lens and the second imaging lens are coupled to the dome to reduce parallax errors for non-paraxial chief rays near the first edge and the second edge and to reduce center of perspective errors within at least a portion of a field of view associated with at least one of the first imaging lens or the second imaging lens.
16. The imaging device of claim 15 , wherein the first imaging lens and the second imaging lens reduce parallax errors or perspective errors by limiting a transverse component of a spherical aberration at a plane at or near the entrance pupil, or by limiting a longitudinal width of the low parallax volume, or by controlling an axial position of a center of perspective at or near the entrance pupil.
17. The imaging device of claim 1 , wherein the first imaging lens and the second imaging lens provide reduced front color experienced by the imaged non-paraxial chief rays from at or near the seam.
18. An imaging device comprising:
a dome defining at least a portion of an interior volume, the dome comprising:
a first lens element,
a second lens element adjacent the first lens element, and
one or more facets formed at a seam between the first lens element and the second lens element, the one or more facets directing a first portion of light rays at the seam to a first imaging lens and directing a second portion of light rays at the seam to a second imaging lens.
19. The imaging device of claim 18 , further comprising:
the first imaging lens disposed in the interior volume and configured to direct light passing through the first lens element to a first image plane; and
the second imaging lens disposed in the interior volume and configured to direct light passing through the second lens element to a second image plane.
20. The imaging device of claim 18 , wherein the one or more facets define a groove extending along the seam, the groove configured to receive a mounting feature on a housing of the first lens element or the second lens element.