Two-channel reflector based single-lens 2D/3D camera with disparity and convergence angle control

Abstract

A single-lens two-channel reflector provides the capability to switch between two-dimensional and three-dimensional imaging. The reflector includes laterally displaceable outward reflectors and displaceable inward reflectors that can simultaneously provide left and right images of a scene to an imager, and controllers for controlling relative distance between the outward and the inward reflectors, and for controlling deflection angle of the inward reflectors, so as to enable the adjustment of disparity and convergence angle.

Claims

1. A single lens two-channel reflector providing disparity and convergence angle adjustability for two-dimensional and three-dimensional imaging, comprising: a reflector arrangement adapted to define a left imaging channel and a right imaging channel, each being defined by a laterally and horizontally displaceable outward reflector and a displaceable inward reflector; a first controller for laterally displacing each laterally and horizontally displaceable outward reflector in its entirety to alter a distance between each said laterally and horizontally displaceable outward reflector and each said displaceable inward reflector; and a second controller for pivoting each displaceable inward reflector to alter a deflection angle of light impinging on said each displaceable inward reflector.

2. The single lens two-channel reflector of claim 1, further including a housing defining left, central, and right imaging inlets, and an imaging outlet.

3. The single lens two-channel reflector of claim 2, wherein the first controller is an idler unit operatively contacting each said laterally displaceable outward reflector for simultaneously translating each said laterally displaceable outward reflector.

4. The single lens two-channel reflector of claim 3, further including at least one biasing element disposed between the housing and each said laterally displaceable outward reflector and adapted to return each said laterally displaceable outward reflector to an original position.

5. The single lens two-channel reflector of claim 2, further including a lens disposed at the imaging outlet.

6. The single lens two-channel reflector of claim 5, further including an adaptor for operatively connecting the single-lens two-channel reflector to an imager.

7. A single lens two-channel reflector-based imaging system providing disparity and convergence angle adjustability, comprising: a reflector arrangement adapted to define a left imaging channel and a right imaging channel, each said left and right imaging channel being defined by a laterally and horizontally displaceable outward reflector and a displaceable inward reflector; a first controller for laterally displacing each laterally and horizontally displaceable outward reflector in its entirety to alter a distance defined between each said laterally and horizontally displaceable outward reflector and each said displaceable inward reflector; a second controller for pivoting each displaceable inward reflector to alter a defined deflection angle of light impinging on said each displaceable inward reflector; a housing defining left, central, and right imaging inlets and an imaging outlet; and an imager operatively connected to the housing imaging outlet.

8. The imaging system of claim 7, wherein said laterally displacing and said pivoting may be selectively applied to orient said laterally displaceable outward reflectors and said displaceable inward reflectors to reflect light to provide one of: a single imaging channel between a scene and the imaging outlet; and said left imaging channel and said right imaging channel providing corresponding left and right views of the scene for comparison to define a disparity therebetween.

9. The imaging system of claim 7, wherein the first controller is an idler unit operatively contacting each said laterally displaceable outward reflector for simultaneously translating each said laterally displaceable outward reflector.

10. The imaging system of claim 9, further including at least one biasing element disposed between the housing and each said laterally displaceable outward reflector and adapted to return each said laterally displaceable outward reflector to an original position.

11. The imaging system of claim 7, further including a lens disposed at the imaging outlet.

12. A method for obtaining two-dimensional and/or three-dimensional images of a scene by a single imager, comprising: providing a single lens two-channel reflector-based imaging system according to claim 7; and manipulating each said laterally and horizontally displaceable outward reflector and said displaceable inward reflector to provide one of a single view or a left and a right view of the scene to the imager.

13. The method of claim 12, comprising pivoting each said displaceable inward reflector to define a single imaging channel between the scene and the imaging outlet to provide a single view of the scene to the imager to provide a two-dimensional rendering of the scene.

14. The method of claim 13, further including displacing each said displaceable inward reflector to contact an edge of each said displaceable inward reflector to said imaging outlet to define the single imaging channel.

15. The method of claim 12, comprising manipulating each said laterally and horizontally displaceable outward reflector and each said displaceable inward reflector to define the left imaging channel and the right imaging channel providing corresponding left and right views of the scene to the imager; comparing said left and right views of the scene to define a disparity between said views; and calculating a depth of objects shown in the scene from said disparity to provide a three-dimensional rendering of the scene.

16. The method of claim 15, including positioning each said displaceable inward reflector to provide a deflection angle of light reflecting from each said laterally and horizontally displaceable outward reflector and impinging on said each displaceable inward reflector.

17. The method of claim 16, further including calculating a location of a left virtual camera and a right virtual camera simulated by said left imaging channel and said right imaging channel.

18. The method of claim 17, further including calculating an original convergence point of said left virtual camera and said right virtual camera.

19. The method of claim 18, further including translating each said laterally and horizontally displaceable outward reflector to alter a distance defined between each said laterally and horizontally displaceable outward reflector and each said displaceable inward reflector to alter an intraocular distance between a first virtual camera and a second virtual camera defined by the left and right imaging channel.

20. The method of claim 19, further including calculating a next convergence point of said left virtual camera and said right virtual camera.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 depicts a prior art two-channel reflector based single lens multi-view imaging system;

(2) FIG. 2 depicts a two-channel reflector according to the present disclosure;

(3) FIG. 3 is a schematic drawing of the two-channel reflector of FIG. 2 showing displacement of the outward mirror units;

(4) FIG. 4 depicts an idler unit for displacing the outward mirror units of FIG. 3;

(5) FIG. 5 depicts actuation of the idler unit of FIG. 4;

(6) FIG. 6 depicts the idler unit of FIG. 3 having displaced the outward mirror units to maximum displacement;

(7) FIG. 7 is a schematic drawing of the two-channel reflector of FIG. 2 showing pivoting of the inward mirror units;

(8) FIG. 8 shows the inward mirror units disposed to define a convergence angle 1;

(9) FIG. 9 shows the inward mirror units pivoted to define a decreased convergence angle 2;

(10) FIG. 10 schematically depicts the two-channel reflector of FIG. 2, including a housing defining a central imaging inlet;

(11) FIG. 11A depicts an embodiment of the two-channel reflector of the present disclosure, placed in two-dimensional mode;

(12) FIG. 11B depicts the two-channel reflector of FIG. 11A configured to provide a central imaging inlet in two-dimensional mode;

(13) FIG. 12A depicts the two-channel reflector of FIG. 11A, placed in three-dimensional mode;

(14) FIG. 12B depicts the two-channel reflector of FIG. 12A, configured for passage of light to an imager through a left imaging channel and a right imaging channel but substantially blocking passage of light through the central imaging channel;

(15) FIG. 13A depicts the two-channel reflector of FIG. 12A, showing pivoting of the displaceable inward mirror units to adjust a light convergence angle;

(16) FIG. 13B illustrates passage of light through the two-channel reflector of FIG. 13A to define two virtual cameras; and

(17) FIG. 14 depicts an imaging system according to the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

(18) In the following detailed description of the illustrated embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration, specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. Also, it is to be understood that other embodiments may be utilized and that process, reagent, materials, software, and/or other changes may be made without departing from the scope of the present invention.

(19) FIG. 2 is a schematic drawing of the two-channel reflector with lens (TCRL) 1 of the present disclosure. As shown in the figure, the present invention two-channel reflector based single lens 2D/3D camera with disparity and convergence angle control uses a two-channel reflector 12 to form the imaging channel. Referring to the figure, a left image inlet 1211, a left laterally displaceable outward reflector such as mirror unit 1212, and a left displaceable inward reflector such as mirror unit 1213 define a left imaging channel 121 in the two-channel reflector 12. It will be appreciated that any suitable light reflector can be utilized. A rotation shaft 1214 assembles with one end of the left inward mirror unit 1213, so the left inward mirror unit 1213 can deflect or pivot around the rotation shaft 1214 as a center. On the other side, a right image inlet 1221, a right displaceable outward mirror unit 1222, and a right displaceable inward mirror unit 1223 form the right imaging channel 122. One end of the right inward mirror unit 1223 is connected to a rotation shaft 1224, so the right inward mirror unit 1223 can deflect around the rotation shaft 1224 as a center. As described above, the left imaging channel 121 and the right imaging channel 122, formed by respective image inlet (1211, 1221), respective outward mirror unit (1212, 1222), and respective inward mirror unit (1213, 1223), define the reflection paths of the images (or light rays).

(20) Referring to the figure, a first controller 123 actuates the outward mirror units (1212, 1222) to cause displacement, so as to change the relative distance between respective outward mirror unit (1212, 1222) and inward mirror unit (1213, 1223). The first controller 123 may comprise an idler unit 1231 such as a CAM unit connected to a rotation disc 1232. The end edges of the idler unit 1231 are operatively coupled to respective outward mirror units (1212, 1222), i.e., the idler unit 1231 can be actuated by operating the first controller 123, so that the outward mirror units (1212, 1222) can be pushed simultaneously to the left and to the right, respectively, by the idler unit 1231. Referring again to the figure, the left imaging channel 121 and the right imaging channel 122 allow the left image (or, left view) L1 and the right image (or, right view) R1 of the scene to enter the two-channel reflector 12 through these two channels (121, 122), then these left and right images (L1, R1) enter the camera through the lens 128 of the two-channel reflector after the reflection by respective outward mirror unit (1212, 1222) and respective inward mirror unit (1213, 1223). As shown in the figure, the configuration of the present reflector produces two virtual cameras (L1, R1), so as to achieve the effect of simultaneous multi-view capturing of a scene by a single camera.

(21) Further as shown in the figure, each unit can be accommodated in a housing 124, and the rotation disc 1232 and the idler unit 1231 of the first controller 123 can be assembled or axis located in the housing 124 so as to be easily operated by operators. One or more biasing elements such as coiled springs 125 may be provided between the housing 124 and respective outward mirror unit (1212, 1222) so the outward mirror unit (1212, 1222) can be returned to its original position by action of the springs 125. Optionally, in order for the present invention to be more compact, portable and functionally complete, a lens set can be disposed in its mechanism so that the whole device can be directly attached to a camera through an adapter ring 127, instead of being attached to the lens of a camera.

(22) As shown in FIG. 3, each outward mirror unit (1212, 1222) can be displaced from its original location (see arrows). After displacement, the relative distance between respective outward mirror unit (1212, 1222) and inward mirror unit (1213, 1223) will change. The relative distance between the two virtual cameras (L1, R1) will change accordingly. This provides adjustment of the intraocular distance.

(23) Referring to the figure, the original location of the left virtual camera L1 (assume it is LVC) can be calculated as set forth below.

(24) Assume and {right arrow over (U.sub.1)} and {right arrow over (U.sub.2)} are unit vectors in the directions of specular reflections of {right arrow over (I.sub.LE)} and {right arrow over (LB)} with respect to AB, respectively, where AB is the mirror surface of the left outward mirror unit (1212). The location LVC of the left virtual camera L1 can be calculated as
LVC=E+t{right arrow over (U.sub.1)}
where t=(.sub.2.sub.3)/.sub.1, with .sub.1, .sub.2 and .sub.3 being determinants of the following matrices

(25) $\left[\begin{array}{cc}{\left(\stackrel{.fwdarw.}{U_1}\right)}_x& {\left(\stackrel{.fwdarw.}{U_1}\right)}_y\\ {\left(\stackrel{.fwdarw.}{U_2}\right)}_x& {\left(\stackrel{.fwdarw.}{U_2}\right)}_y\end{array}\right],\left[\begin{array}{cc}{B}_x& B_y\\ {\left(\stackrel{.fwdarw.}{U_2}\right)}_x& {\left(\stackrel{.fwdarw.}{U_2}\right)}_y\end{array}\right],\left[\begin{array}{cc}{E}_x& E_y\\ {\left(\stackrel{.fwdarw.}{U_2}\right)}_x& {\left(\stackrel{.fwdarw.}{U_2}\right)}_y\end{array}\right],$
respectively. Location of the right virtual camera is symmetric to the left virtual camera about the optical axis of the camera (the y-axis).

(26) When the left outward mirror unit 1212 moves to the left (in x direction), the intersection of light ray {right arrow over (I.sub.LE)} with the left outward mirror unit 1212 changes from E to F, and the intersection of light ray {right arrow over (LB)} with the left outward mirror unit 1212 changes from B to G. New location of the left virtual camera L1 can be calculated by the following formula:
LVC=F+t.sub.1{right arrow over (U.sub.1)}
where t.sub.1=(.sub.2.sub.3)/.sub.1, with .sub.2 and .sub.3 being determinants of the following matrices:

(27) $\left[\begin{array}{cc}{G}_x& G_y\\ {\left(\stackrel{.fwdarw.}{U_2}\right)}_x& {\left(\stackrel{.fwdarw.}{U_2}\right)}_y\end{array}\right]\mathrm{and}\left[\begin{array}{cc}{F}_x& F_y\\ {\left(\stackrel{.fwdarw.}{U_2}\right)}_x& {\left(\stackrel{.fwdarw.}{U_2}\right)}_y\end{array}\right],$
respectively, and .sub.1 being defined as above.

(28) Changing the intraocular distance of the virtual cameras can change their convergence point. Let {right arrow over (U.sub.1)} and {right arrow over (U.sub.2)} be unit vectors in optical axes of the left and right virtual cameras, respectively, and they can be obtained as below:
{right arrow over (U.sub.1)}=({right arrow over (U.sub.1)}+{right arrow over (U.sub.2)})/{right arrow over (U.sub.1)}+{right arrow over (U.sub.2)}
{right arrow over (U.sub.x)}=(({right arrow over (U.sub.1)}).sub.x,({right arrow over (U.sub.1)}).sub.y)
RVC=((LVC).sub.x,(LVC).sub.y)

(29) The original convergence points CP of the right virtual camera RVC and the left virtual camera LVC can be calculated by the following formula:
CP=LVC+t.sub.2{right arrow over (U.sub.1)}
where t.sub.2=(.sub.5.sub.6)/.sub.4, .sub.4, .sub.5 and .sub.6 being determinants of the following matrices:

(30) $\left[\begin{array}{cc}{\left(\stackrel{.fwdarw.}{U_l}\right)}_x& {\left(\stackrel{.fwdarw.}{U_l}\right)}_y\\ {\left(\stackrel{.fwdarw.}{U_r}\right)}_x& {\left(\stackrel{.fwdarw.}{U_r}\right)}_y\end{array}\right],\left[\begin{array}{cc}{\left(\mathrm{RVC}\right)}_x& {\left(\mathrm{RVC}\right)}_y\\ {\left(\stackrel{.fwdarw.}{U_r}\right)}_x& {\left(\stackrel{.fwdarw.}{U_r}\right)}_y\end{array}\right],\left[\begin{array}{cc}{\left(\mathrm{LVC}\right)}_x& {\left(\mathrm{LVC}\right)}_y\\ {\left(\stackrel{.fwdarw.}{U_r}\right)}_x& {\left(\stackrel{.fwdarw.}{U_r}\right)}_y\end{array}\right]$
respectively. The new locations LVC and RVC of the virtual cameras can be obtained after changing the intraocular distance of the left and right virtual cameras. The formula for computing LVC is described as above. RVC and LVC are symmetric to the optical axis (y axis) of the camera. The new location of convergence point CP is calculated by:
CP=LVC+t.sub.3{right arrow over (U.sub.1)}
where t.sub.3=(.sub.5.sub.6)/.sub.4, and .sub.5 and .sub.6 being determinants of the following matrices:

(31) $\stackrel{.fwdarw.}{\left[\begin{array}{cc}{\left({\mathrm{RVC}}^{}\right)}_x& {\left({\mathrm{RVC}}^{}\right)}_y\\ {\left(\stackrel{.fwdarw.}{U_r}\right)}_x& {\left(\stackrel{.fwdarw.}{U_r}\right)}_y\end{array}\right]}\mathrm{and}\left[\begin{array}{cc}{\left({\mathrm{LVC}}^{}\right)}_x& {\left({\mathrm{LVC}}^{}\right)}_y\\ {\left(\stackrel{.fwdarw.}{U_r}\right)}_x& {\left(\stackrel{.fwdarw.}{U_r}\right)}_y\end{array}\right],$
while .sub.6 is defined as above.

(32) FIGS. 4 to 6 depict an embodiment of a first controller 123 for displacing the displaceable outward mirrors. FIG. 4 is a schematic showing each outward mirror unit (1212, 1222) located at its original position. In FIG. 5, when adjusting disparity during imaging, a user actuates a rotation disc 1232 of the first controller 123 to cause the idler unit 1231 to move. As shown in the figures, the idler unit 1231 rotation simultaneously displaces each outward mirror unit (1212, 1222) in opposite directions. FIG. 6 is a schematic showing each outward mirror unit (1212, 1222) at maximum displacement. Thus, adjusting the first controller 123 adjusts the intraocular distance and so the disparity when imaging.

(33) FIG. 7 shows adjustment of a convergence angle in the imaging process. When the convergence angle is changed by pivoting displaceable inward mirror units 1213, 1223, a suitable deflection angle is generated in respective inward mirror units (1213, 1223) so as to change a refraction angle between respective inward mirror units (1213, 1223) and the corresponding outward mirror units (1212, 1222), thus changing the convergence angle. FIG. 8 shows respective inward mirror units (1213, 1223) prior to deflection, assuming the original convergence angle is 1. FIG. 9 shows use of the inward mirror units 1213, 1223 to change the convergence angle in the imaging process (the convergence angle is to be decreased). The respective inward mirror units (1213, 1223) are pivoted by actuating the second controller (126) so as to further change its angle. Referring to the figure, when the left inward mirror unit 1213 generates clockwise deflection by the rotation shaft 1214 and the right inward mirror unit 1223 generates counterclockwise deflection by the rotation shaft 1224, the original convergence angle 1 will gradually decrease to 2 (as shown in the figure). On the contrary, the convergence angle will gradually increase. Again, the old and new convergence point locations can be obtained by the aforementioned method for computing CP and CP.

(34) FIG. 10 schematically shows a system structure (housing 124) which defines a central imaging inlet 1241. By this housing 124, the two channel reflector can be used for 2D or 3D imaging to extend its overall practical value. If only 2D imaging is needed in implementation, operators can drive the rotation shafts (1214, 1224) via second controller 126 to pivot the inward mirror units (1213, 1223) to cause a deflection. As shown in the figure, when two opposite inward mirror units (1213,1223) deflect to a suitable angle (that is, the left and right inward mirror units (1213, 1223) are overlapped with the left and right boundaries of the horizontal field of view (FOV) of the imager), a central imaging channel 13 is formed between these two units, and the image (or light rays) entering from the left and right imaging channel only conducts total reflection between the outward and the inward mirror units, thus being unable to reach the imager. In this way, the imager can only capture a single image, so it is suitable for 2D imaging. On the other hand, to switch to 3D mode to conduct imaging, the two opposite inward mirror units (1213, 1223) are first deflected or pivoted back to their original locations by the control of the second controller 126. In this manner, the present two channel reflector can be adapted for 2D or 3D imaging according to the operator's preference.

(35) In more detail (see FIGS. 11-13), an initial situation, the 2D mode, is depicted in FIGS. 11A-11B. In this situation, axis of the second controller 126 is at the right end of a slot switch (see FIG. 11A), and the left inward mirror unit 1213 and the right inward mirror unit 1223 are slightly behind the left boundary and the right boundary of the imager's horizontal field of view (FOV), respectively, and consequently a central imaging inlet 13 is formed (see FIG. 11B). When the second controller is pulled to the left (see FIGS. 12A-12B), the axis of the controller 126 pushes the mechanical part 130 upward which, in turn, forces arm of the left inward mirror unit 1215 and arm of the right inward mirror unit 1225 to rotate about the rotation shafts (1214, 1224) counterclockwise and clockwise, respectively (see FIG. 12A), so that the inward mirror units 1213, 1223 would be moved toward the positions shown in FIG. 12B. This is the initial stage of the 3D mode. In this situation, light rays can reach the imager through the left imaging channel 121 and the right imaging channel 122, but most of the light rays entering the central imaging channel 13 will be blocked by the inward mirror units. In this situation, the left inward mirror unit 1213 and the right inward mirror unit 1223 are close to each other, but not contacting (see FIG. 12B) and the mechanical part 130 is close to but not contacting the housing 124 (see FIG. 12A).

(36) The room left between the left inward mirror unit 1213 and the right inward mirror unit 1223 (also, the room left between the mechanical part 130 and the housing 124) can be used to adjust the convergence angle of the 3D mode. By adjusting the location of the second controller 126 between the left end of the slot switch and its location in FIG. 12 (see FIGS. 13A-13B), the operator can adjust the convergence angle accordingly.

(37) FIG. 14 depicts an imaging system according to the present disclosure. The imaging system 1 including a two channel reflector with lens 1 providing disparity and convergence angle control as described above is constructed in such a manner that, in its outside appearance, the first controller 123 and the second controller 126 are disposed on the housing 124 for easy access and operation. As to the figure, the present invention is assembled to the lens mount 301 of a camera 30 by an adapter ring 127. Operation can be conducted as described above after assembly is completed.

(38) Summarizing, the present disclosure provides an imaging system where the outward mirror unit location is changed to change the relative distance between the outward and the inward mirror unit to control the disparity. Further, the present disclosure provides an imaging system where the inward reflection unit deflection angle is adjusted in micro-scale to control the convergence angle. Moreover, the present disclosure provides an imaging system where the inward reflection unit deflection angle is adjusted so that a central image inlet is formed between two opposite inward mirror units. In this case, the opposite total-reflection is formed between the outward and the inward mirror unit to block the image (or light rays) from entering the right and the left imaging channel to form 2D image mode. In this manner, the present invention can provide an imaging system enabling the control of disparity, convergence angle, and the operation of 2D or 3D image mode operation.

(39) One of ordinary skill in the art will recognize that additional embodiments of the invention are also possible without departing from the teachings herein. Thus, the foregoing description is presented for purposes of illustration and description of the various aspects of the invention, and one of ordinary skill in the art will recognize that additional embodiments of the invention are possible without departing from the teachings herein. This detailed description, and particularly the specific details of the exemplary embodiments, is given primarily for clarity of understanding, and no unnecessary limitations are to be imported, for modifications will become obvious to those skilled in the art upon reading this disclosure and may be made without departing from the spirit or scope of the invention. Relatively apparent modifications, of course, include combining the various features of one or more figures with the features of one or more of other figures. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.