Optical imaging system and device for floating display, and surround-view display device

1 . An optical imaging system for floating display, the optical imaging system sequentially defining an object plane, a first image plane, and a second image plane along an optical axis thereof, the optical imaging system comprising:

at least one imaging unit comprising a main imaging unit, the main imaging unit being located downstream of the object plane and configured to converge a light beam from a point on the object plane on the first image plane to form a line image in the first direction, and the first image plane being located downstream of the main imaging unit; and

a main diffusor located downstream of the main imaging unit and configured to diverge light in a second direction that is different from the first direction,

wherein the second image plane is located downstream of the main diffusor and the first image plane, the at least one imaging unit is configured to converge a light beam from a point on the object plane on the second image plane to form a line image in the second direction, wherein the second image plane is a floating image plane,

wherein said main imaging unit, said first image plane and the second image plane are located at different axial positions along the optical axis, and

wherein the main imaging unit has different light-converging capabilities in the first direction and the second direction.

2 . The optical imaging system of claim 1 , further comprising an additional diffusor disposed at the object plane for diverging light in the first direction.

3 . The optical imaging system of claim 1 , wherein the main imaging unit is a one-dimensional retroreflector.

4 . The optical imaging system of claim 1 , wherein the at least one imaging unit further comprises an auxiliary imaging unit disposed between the object plane and the main diffusor, and the auxiliary imaging unit comprises a one-dimensional aperture stop for constraining light from the object plane in the second direction.

5 . The optical imaging system of claim 1 , wherein:

the at least one imaging unit further includes an auxiliary imaging unit such that the optical imaging system further defines one or more relay image planes that are located between the object plane and the main diffusor along the optical axis, and the optical imaging system further includes an additional diffusor disposed within the depth of focus of a particular one of the one or more relay image planes for diverging light in the first direction.

6 . The optical imaging system of claim 5 , wherein the auxiliary imaging unit is configured to cause a light beam from a point on the object plane to form a line image in the second direction at the particular relay image plane.

7 . The optical imaging system of claim 1 , wherein the main diffusor is positioned at an angle with respect to the optical axis.

8 . The optical imaging system of claim 1 , further comprising a louver mask structure for controlling the angle of the light.

9 . The optical imaging system of claim 1 , wherein the at least one imaging unit comprises one or more of the following:

a one-dimensional retroreflector for converging light in the first direction;

a toric mirror for modulating light in the first direction and the second direction simultaneously;

an optical waveguide for propagating light therein;

a cylindrical lens for converging light in one direction without changing the propagation of light in another direction orthogonal to said direction; and

a lens group located between the object plane and the first image plane along the optical axis, for propagating light therebetween.

10 . The optical imaging system of claim 1 , wherein the optical imaging system has an infinite depth of focus in the second direction for the first image plane, and wherein the first image plane is located at any position between the at least one imaging unit and the second image plane.

11 . The optical imaging system of claim 1 , wherein the main imaging unit comprises: a lens configured to be mechanically moved along the optical axis in the y-direction, with the movement being sufficiently rapid such that a movement cycle is less than 0.1 seconds to enable dynamic adjustment of the focal point, or a fast zoom function lens configured to enable adjustment of the focal length along the optical axis within less than 0.1 seconds.

12 . The optical imaging system of claim 1 , wherein the at least one imaging unit further includes a transflective lens disposed between the object plane and the main imaging unit and between the main imaging unit and the main diffusor along the optical path.

13 . The optical imaging system of claim 12 , wherein the imaging light from the object plane is incident on the main imaging unit via the transflective lens, and the imaging light emitted from the main imaging unit is reflected on the main diffusor through the transflective lens.

14 . The optical imaging system of claim 1 , wherein the object plane and the main diffusor are arranged parallel to each other.

15 . The optical imaging system of claim 1 , wherein the image height of the optical imaging system in the first direction is equal to the object height in the first direction.

16 . The optical imaging system of claim 1 , wherein the object plane and the second image plane are in an upright imaging relationship.

17 . A floating display device, comprising:

the optical imaging system of claim 1 ; and

an image display unit configured to emit light constituting an image toward the object plane of the optical imaging system.

18 . The floating display device of claim 17 , wherein:

the image display unit is a direct-view display source, and a display surface of the image display unit is provided at the object plane; or

the image display unit is a projection-based display source, and the projection surface of the image display unit is provided at the object plane.

19 . A surround-view display device, comprising:

a plurality of floating display devices according to claim 17 are arranged in a stitched manner.