CN116366974A

CN116366974A - Stereoscopic imaging system based on folding parallel light channel

Info

Publication number: CN116366974A
Application number: CN202210149212.0A
Authority: CN
Inventors: 郑楷先
Original assignee: Amec Video Technology Co ltd
Current assignee: Amec Video Technology Co ltd
Priority date: 2021-12-22
Filing date: 2022-02-18
Publication date: 2023-06-30

Abstract

The present invention provides a stereoscopic imaging system comprising a pair of folded-parallel-light-channel (FPLC) units arranged to provide a virtual left side view and a virtual right side view of a scene. Each FPLC cell includes a fixed lens cell adapted to focus reflected light comprising an image of the scene onto the image sensor, and a light redirecting cell including a reflector adapted to define parallel image reflection paths to the fixed lens cell via the collimated light beam.

Description

Stereoscopic imaging system based on folding parallel light channel

Technical Field

The present invention relates to stereoscopic/three-dimensional imaging. More particularly, the present invention relates to a compact folded-parallel-light-channel (FPLC) stereoscopic imaging system that synchronously generates left and right views of a scene that can be compiled into three-dimensional (3D) images. The disclosed stereoscopic imaging system may be used in a variety of devices, including compact mobile devices, such as cell phones and smart phones.

Background

A key point in designing an embedded imaging system for a handheld or other mobile device, such as a cell phone or smart phone, is to ensure that the height (thickness) of the imaging system is less than (or at least very close to) the thickness of the cell phone. The image sensor of the cell phone imaging system has a fixed dimension (4.80 mm x 3.60 mm). To ensure that an image of the same size as the image sensor is generated, the size of lenses used in the imaging system of the cell phone cannot be reduced without limitation. Thus, tele cameras cannot generally be used in mobile devices such as smartphones, because when equipped with a camera comprising a plurality of lenses arranged to refract light to form an image at a cell phone camera image sensor (cell phone camera image sensor, CPCIS), the height of such a camera needs to be at least 14 mm (see fig. 1 for example), whereas typical smartphones are only between 7 mm and 9 mm thick.

In order to allow embedding a CPCIS equipped tele camera in a smart phone, prior art devices are known (see FIG. 2), wherein the tele camera is "folded" by inserting a refractive lens in the lens system such that the optical axis (see dashed line) is redirected from vertical to horizontal once it reaches the refractive lens. The image sensor is mounted in an orientation defining a plane that is oriented perpendicularly with respect to the plane defined by the ground, rather than parallel to the plane defined by the ground. By folding the CPCIS equipped tele camera in this way, the height of the camera can be as small as 7 mm, which can be embedded in a smart phone. See, for example, U.S. patent No. 9,316,810 to Mercado and U.S. patent No. 9,172,856 to Bohn et al, the entire disclosures of each of which are incorporated herein by reference.

Theoretically, the hypothetical structure shown in fig. 3 could be defined by symmetrically arranging two identical imaging systems (such as those shown in fig. 2) to provide a stereoscopic imaging system. Such hypothetical stereoscopic imaging systems could potentially be embedded in mobile devices such as larger, thicker cell phones or smartphones. However, consumers prefer smaller, thinner handsets and smartphones that do not sacrifice characteristics such as processing power, camera quality, etc. due to such reduced size/thickness. Because of the vertical portion of the device, the stereoscopic imaging system shown in fig. 3 defines a larger vertical (x-axis) profile, thus requiring additional packaging space along the x-axis, which can be costly in smaller mobile devices, such as smaller, thinner cell phones and smartphones. Furthermore, as shown in fig. 3, each ray is reflected by the reflector at a respective angle and must be collected/rerouted to the image sensor to transmit the image. The relative spacing of the two refractive lens units with respect to each other and the relative spacing of the lenses and reflectors to define the parallax or interocular distance of the device is critical and cannot be altered without sacrificing image quality or requiring additional corrective measures. Accordingly, although the refractive lens unit arrangement shown in fig. 3 can be used to fold light to reflect an incoming 2D image to an image sensor to process the 2D image into a 3D image, the inter-ocular distance/spacing between the lens units cannot be changed due to the configuration of each lens unit and does not negatively affect the quality of the generated 3D image (i.e., the accuracy of the depth values of the combined 2D image).

Accordingly, there is a need in the art for improved imaging systems for smaller, thinner mobile devices, providing stereoscopic imaging systems that are capable of converting 2D images to 3D images and that can be implemented in smaller, thinner modern cell phones and smart phones. The following disclosure describes a folded parallel light channel stereoscopic imaging system for such a mobile device.

Disclosure of Invention

In order to solve the above-described problems and to seek to solve the needs identified in the art, in one aspect of the present invention, a stereoscopic imaging system includes: two Folded Parallel Light Channel (FPLC) units are arranged to provide a virtual two-dimensional left side view and a virtual two-dimensional right side view of the scene. Each FPLC cell includes: a) A fixed lens unit adapted to focus reflected light comprising an image of a scene onto the image sensor; and b) a refractive unit comprising a reflector adapted to define parallel image reflection paths along a y-axis of the stereoscopic imaging system to the fixed lens unit via the collimated light beam. The fixed lens units and refractive units of each FPLC cell are disposed at a predetermined separation distance from each other along the y-axis to provide a desired parallax or interocular function for the system. The stereoscopic imaging system is adapted to combine the virtual two-dimensional left side view and the virtual two-dimensional right side view into a single three-dimensional image.

In an embodiment, the reflector defines a planar reflective surface. The system may further include a concave lens disposed between the reflector and the imaging portal of each FPLC cell, the concave lens defining a lens field of view identical to the field of view of the stationary lens cell.

In other embodiments, the reflector defines an arcuate reflective surface. The arcuate reflective surface may be configured to define a reflector field of view that is the same as the field of view of the fixed lens unit.

In an embodiment, the fixed lens unit defines a wide angle lens unit or a tele lens.

In another aspect, a stereoscopic imaging system is provided comprising two Folded Parallel Light Channel (FPLC) units arranged to provide a virtual two-dimensional left side view and a virtual two-dimensional right side view of a scene. As previously described, the stereoscopic imaging system is adapted to combine the virtual two-dimensional left side view and the virtual two-dimensional right side view into a single three-dimensional image. The fixed lens unit and refractive unit of each FPLC cell are substantially as described above, and are disposed at predetermined separation distances along the y-axis to provide the desired parallax or eye distance function for the system. The stereoscopic imaging system is adapted to combine the virtual two-dimensional left side view and the virtual two-dimensional right side view into a single three-dimensional image. The fixed refractive unit comprises a planar reflector and may comprise a concave lens configured to define the same reflector field of view as the field of view of the fixed lens unit described above.

In a further aspect, a stereoscopic imaging system is provided comprising two Folded Parallel Light Channel (FPLC) units arranged to provide a virtual two-dimensional left side view and a virtual two-dimensional right side view of a scene. As previously described, the stereoscopic imaging system is adapted to combine the virtual two-dimensional left side view and the virtual two-dimensional right side view into a single three-dimensional image. The fixed lens unit and refractive unit of each FPLC cell are substantially as described above and are disposed at predetermined separation distances along the y-axis to provide the desired parallax or eye distance function for the system. The stereoscopic imaging system is adapted to combine the virtual two-dimensional left side view and the virtual two-dimensional right side view into a single three-dimensional image. The fixed refractive unit comprises a convex reflector and may comprise a concave lens configured to define the same reflector field of view as the field of view of the fixed lens unit described above.

These and other embodiments, aspects, advantages, and features of the invention will be set forth in the description which follows and in part will become apparent to those having ordinary skill in the art by reference to the following description and referenced drawings or by practice. The aspects, advantages, and features of the invention are realized and attained by means of the instrumentalities, procedures, and combinations particularly pointed out in the appended claims. Any patent and/or non-patent citations discussed herein are incorporated by reference in their entirety unless otherwise indicated.

Drawings

FIG. 1 depicts a prior art imager for a mobile device such as a cell phone or smart phone;

FIG. 2 depicts a prior art folded light path imager for a mobile device such as a cell phone or smart phone;

FIG. 3 shows a phantom stereoscopic imager derived from the imager of FIG. 2;

fig. 4 schematically illustrates a stereoscopic imaging system according to the invention;

fig. 5 shows a folded parallel light channel based camera unit used in the stereoscopic imaging system of fig. 4 in isolation;

FIG. 6 illustrates the operation of a convergence angle adjustment mechanism for the stereoscopic imaging system of FIG. 4;

fig. 7 shows separately a folded parallel light channel based camera unit for the stereoscopic imaging system of fig. 4, the camera unit comprising a folded unit with a curved reflective surface and a multi-lens block unit comprising three lenses;

FIG. 8 shows a curved reflector for use in the camera unit of FIG. 7;

fig. 9 shows separately a folded parallel light channel based camera unit for the stereoscopic imaging system of fig. 4, the camera unit comprising a folded unit with a curved reflective surface and a multi-lens block unit comprising five lenses;

fig. 10 shows separately a folded parallel light channel based camera unit for use in the stereoscopic imaging system of fig. 4, the camera unit comprising a folded unit having a planar reflective surface and a multi-lens block unit comprising three lenses;

fig. 11 shows separately a folded parallel light channel based camera unit for use in the stereoscopic imaging system of fig. 4, the camera unit comprising a folded unit having a planar reflective surface and a multi-lens block unit comprising five lenses;

fig. 12 shows a parallax adjustment mechanism for the stereoscopic imaging system of fig. 4; and is also provided with

Fig. 13 shows a stereoscopic imaging system comprising two fixed folded parallel light channel based camera units.

Detailed Description

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. In addition, it is to be understood that other embodiments may be utilized and that process, reagents, materials, software, and/or other changes may be made without departing from the scope of the present invention.

The present invention is directed to a stereoscopic imaging system 100 for a mobile device that not only has a small thickness dimension, but also has the capability of parallax and convergence angle control. Referring to fig. 4 and 5, the stereoscopic imaging system 100 includes two substantially identical FPLC-based camera units 102a, 102b symmetrically arranged to synchronously generate left and right views of a scene viewed by the stereoscopic imaging system. Each FPLC based camera unit 102a, 102b is contained in a separate

pivotable housing

103a, 103 b. The FPLC based camera units 102a, 102b each include a

refractive unit

104a, 104b for folding into the optical path (see dashed lines) of the FPLC based camera, and a

multi-lens block unit

106a, 106b for forming an image. Light rays entering the

refractive units

104a, 104b of the FPLC based cameras 102a, 102b on a first light path are redirected by folding elements 108a, 108b (not shown in this view) to a second light path, which is a collimated light beam comprising parallel oriented light rays (see solid lines). The folding elements 108a, 108b may comprise flat reflective surfaces or curved reflective surfaces. The parallel oriented rays of the collimated light beam are then refracted by lenses (not shown in this view) of the

multi-lens block unit

106a, 106b in the second optical path to form an image at the

image sensors

110a, 110b. As will be described, each FPLC-based camera 102a, 102b may be configured to provide a tele lens system embodiment or a wide lens system embodiment. Each of the embodiments satisfies the requirement of parallel oriented light transmission between the

refractive units

104a, 104b and the

multi-lens block units

106a, 106b.

As representatively shown in fig. 5, each FPLC-based camera unit 102a, 102b defines, by its configuration, a

virtual camera

112a, 112b, respectively (only virtual camera 112a is shown in the figure), which represents a left or right view, respectively, of a scene as transferred to each

image sensor

110a, 110b.

In either embodiment, the parallax of the left and right views of the stereoscopic imaging system 100 may be adjusted by adjusting the distance between the

refractive units

104a, 104b of the two FPLC based camera units 102a, 102 b. Likewise, the convergence angle of the left and right views of the stereoscopic imaging system 100 may be adjusted by adjusting the angle between the left and right FPLC-based camera units 102a, 102 b. The mechanism to achieve these adjustments will be described below.

Fig. 7, 8 and 9 illustrate embodiments of the FPLC based camera units 102a, 102b, the camera units 102a, 102b comprising folding elements 108a, 108b having curved reflective surfaces. In the embodiment shown in fig. 7, the multi-lens block unit 106a includes three

lenses

114a, 114b, 114c. In the embodiment shown in fig. 9, the multi-lens block unit 106a includes five

lenses

114a, 114b, 114c, 114d, and 114e. As will be appreciated, the curved folding elements 108a, 108b are arranged to have a curvature, whereby the field of view of the curved folding elements 108a, 108b is the same as the field of view of the

multi-lens block unit

106a, 106b. In this embodiment, the field of view of the curved folding elements 108a, 108b defines the field of view of the FPLC based camera units 102a, 102 b.

Fig. 10 and 11 illustrate embodiments of the FPLC based camera units 102a, 102b, the camera units 102a, 102b comprising folding elements 108a, 108b having planar reflective surfaces. Fig. 10 shows an FPLC based camera unit 102a having a multi-lens block unit 106a including three

lenses

114a, 114b, 114c, while fig. 11 shows an FPLC based camera unit 102a having a multi-lens block unit 106a including five

lenses

114a, 114b, 114c, 114d, and 114e. In these embodiments, concave lenses 116a, 116b (only lens 116a is shown in the figures) are provided as part of the

refractive units

104a, 104b in the optical path into the FPLC based camera unit. As will be appreciated, the concave lenses 116a, 116b are arranged to have curvature, whereby the field of view of the concave lenses 116a, 116b is the same as the field of view of the

multi-lens block unit

106a, 106b. In this embodiment, the field of view of the concave lenses 116a, 116b defines the field of view of the FPLC based camera units 102a, 102 b.

As will be appreciated, by ensuring that the field of view of the

refractive units

104a, 104b is the same as the field of view of the

multi-lens block units

106a, 106b as described above, the

multi-lens block units

106a, 106b are able to provide the same size image of the scene as the

image sensors

110a, 110b. Further, since the traveling paths of the light rays from the refractive elements 108a, 108b to the

multi-lens block units

106a, 106b as collimated light beams are parallel, the fields of view of the

refractive units

104a, 104b are independent of the pitch or distance of the refractive units from the

multi-lens block units

106a, 106b. With this feature, parallax can be adjusted by the mechanism described below without moving the

multi-lens block units

106a, 106b and/or the

image sensors

110a, 110b.

Fig. 7 and 10 show wide-angle

multi-lens block units

106a, 106b paired with curved refractive units and planar

refractive units

104a, 104b, respectively. In turn, fig. 9 and 11 show tele multi-lens

block units

106a, 106b paired with curved refractive unit 104a and planar refractive unit 104b, respectively. In each case, the field of view of the

refractive units

104a, 104b is the same as the field of view of the

multi-lens block units

106a, 106b. However, it should be understood that the described stereoscopic imaging system 100 is not limited to wide angle lens systems and tele lens systems, but may be configured with any suitable lens system, wherein the

refractive units

104a, 104b may be configured with the same field of view as the

multi-lens block units

106a, 106b so that the multi-lens block units may produce the same size scene image as the

image sensors

110a, 110b included in the stereoscopic imaging system.

As described above in the discussion of fig. 4 and 5, the

refractive units

104a, 104b define

virtual cameras

112a, 112b, described as left and right

virtual cameras

112a, 112b, respectively, with reference to the orientation of the stereoscopic imaging system 100. The distance D (see fig. 4 and 6) between the left virtual camera 112a and the right virtual camera 112b is variously referred to as an inter-eye distance, a virtual camera parallax, or simply parallax. It is this distance D that determines the disparity between the left and right views of the scene. In turn, each

virtual camera

112a, 112b has a line of sight, referred to as an optical axis O (see fig. 5, 7, and 9-11). The angle between the optical axes of the

virtual cameras

112a, 112b is referred to as convergence angle a (see fig. 6). Advantageously, the stereoscopic imaging system 100 described herein provides for adjustment of interocular distance/parallax and convergence angle.

With respect to the adjustment of the convergence angle, referring back to fig. 4 and 6, each FPLC based camera unit 102a, 102B housing 103a, 103B is pivotally (see fig. 6, arrow B) attached to the stereoscopic imaging system housing 118. In the depicted embodiment, the FPLC based camera units 102a, 102b are pivotally attached to the stereoscopic imaging system housing 118 by

rotational axes

120a, 120b, respectively. A convergence angle adjustment mechanism 122 is provided, which in the depicted embodiment includes a biasing actuator 124 and at least two biasing members 126. Rotating the biasing actuator 124 in a first direction will cause each

camera unit housing

103a, 103b to rotate about an axis defined by the

rotational axes

120a, 120b, thereby altering the angle between the optical axes O of the FPLC-based camera units 102a, 102b, thereby altering the convergence angle of the stereoscopic imaging system 100. Rotation of the biasing actuator 124 in a second opposite direction with the aid of the biasing action of the biasing member 126 will return the camera unit housing to its original orientation. In turn, the biasing action of the biasing member 126 ensures stability of the adjustment process.

Referring to fig. 4 and 12, a parallax adjustment mechanism 128 is also provided. In the depicted embodiment, the parallax adjustment mechanism 128 includes an arrangement of guide rods 130, with each

refractive unit

104a, 104b slidably attached to the guide rods 130. A cam array 132 is provided, disposed between each

refractive unit

104a, 104b and under the control of a parallax adjustment actuator 134. In the depicted embodiment, the cam array 132 includes a pair of

elliptical cams

136a, 136b that are configured to actuate the parallax adjustment actuator 134 to rotate the

cams

136a, 136b in opposite directions (see arrows). As will be appreciated, this will bias the

refractive units

104a, 104b to translate them laterally to increase the distance between them. In turn, a plurality of biasing members 138 (in the depicted embodiment, springs concentric about each guide rod 130) are provided to bias the

refractive units

104a, 104b toward each other in a direction opposite to the biasing force applied by the cam array. Thus, with such a parallax adjustment mechanism 128, the

refractive units

104a, 104b may be laterally translated to alter the distance therebetween, and with such a mechanism, the parallax for the stereoscopic imaging system 100 may be controlled. Also, the biasing member 138 provides stability to the parallax adjustment process.

In yet another embodiment of the disclosed stereoscopic imaging system, it is contemplated to provide a system that includes a pair of stationary FPLC cells as described above to allow for the incorporation of tele lenses or other lens devices into mobile devices such as cell phones or smartphones. As previously described, by configuring the pair of photo lens units shown in fig. 2 into the hypothetical arrangement disclosed in fig. 3 to allow for "folding" of the light/image, the stereoscopic imaging system may be configured to create a 3D image from the captured 2D scene image. This reduces the footprint of the stereoscopic imaging system, potentially allowing implementation in mobile devices such as larger cell phones/smartphones. However, implementing such stereoscopic imaging systems into mobile devices suffers from a number of drawbacks, mainly involving the need for additional packaging space that may be necessary and may not be available in smaller mobile devices (such as cell phones or smartphones) without sacrificing other required or desired functionality. Furthermore, such systems would be hindered by the relatively short focal length of small devices such as cell phone/smart phone cameras.

In the refractive lens unit depicted in fig. 2 and the virtual stereoscopic imaging system depicted in fig. 3, an image (light) is received through a first group of lenses and redirected through an interposed reflector to a second group of lenses. Therefore, these refractive lens units have three elements: a) A vertical (y-axis) portion comprising a first set of lenses; b) An intermediate reflector; and c) a horizontal (x-axis) portion comprising a second group of lenses. Due to the vertical portion, the phantom stereoscopic imaging system of fig. 3 will define a larger vertical (y-axis) profile, which requires additional packaging space along the y-axis that is relatively costly in smaller mobile devices such as cell phones and smartphones. Further, as shown in fig. 3, each light ray is reflected from the reflector at each angle. Thus, while the hypothetical system of fig. 3 can be used to refract light to reflect an incoming image to an image sensor, due to the configuration of lenses and reflectors of each refractive lens unit, the interocular distance/spacing between the individual refractive lens units cannot be altered without adversely affecting the quality of the created 3D image (i.e., the accuracy of the depth values of the combined 2D image).

To solve these and other problems, the present invention also relates to a stereoscopic imaging system 200 that does not require a refractive lens unit as shown in fig. 2 to 3 or parallax/convergence control as shown in fig. 4. For example, the stereoscopic imaging system 200 implements the configuration of the above-described FPLC-based camera units 102a, 102b (see fig. 4-5), whereby the functionality of folding and concentrating image light to the

image sensors

110a, 110b at a desired field-of-view size is provided by the respective

refractive units

104a, 104b and the plurality of

lens block units

106a, 106b (each arranged in a coplanar configuration along the device x-axis), in the depicted embodiment, tele lenses.

With reference to fig. 13, it is apparent that this configuration provides a more compact profile, particularly along the y-axis (i.e., depth of the device), as there is no need to provide lenses above the

refractive units

104a, 104b. Also, because all lenses are contained within the

multi-lens block units

106a, 106b, the distance D between the FPLC-based camera units 102a, 102b (and thus the parallax/interocular distance of the stereoscopic imaging system) may be altered depending on the particular mobile device (not shown) in which the stereoscopic imaging system 200 is to be implemented. This available increase in parallax further advantageously allows a larger range of optical axis settings of the FPLC-based camera units 102a, 102b, i.e. larger or smaller angles relative to each other as needed to alter the focus of the combined stereoscopic system 200 according to the dimensions and capabilities of the mobile device to be implemented therein. As will be appreciated, this feature allows the focus of the mobile device camera incorporating the presently described stereoscopic imaging system 200 to be extended beyond the focus available for conventional mobile device cameras.

This is because it is well known that a 3D image can be created from any device that includes a camera capable of capturing two 2D images of a scene and combining the two 2D images, such as by conventional triangulation algorithms. However, the quality of the created 3D image may differ according to the set parallax and focus (convergence angle) of the camera used. Due to the limitations of conventional cameras for mobile devices, this focus is placed very close to the device. Thus, for a conventional cell phone or smartphone camera, even with the hypothetical device of fig. 3, acceptable 3D image quality can only be achieved by taking 2D images at a distance very close to the set focus of the camera used.

On the other hand, the device of fig. 13, in addition to providing a reduced y-axis profile and thus allowing this y-axis profile to be implemented in a thinner device, allows the use of 2D images captured from a greater distance (than is possible using the hypothetical device of fig. 3), while still being able to create 3D images from such 2D images due to the enhanced focal distance that can be achieved. As described above, this is because for the device of fig. 13, the parallax/interocular distance can be changed by separating the individual FPLC-based camera units 102a, 102b to the greatest extent allowed in the dimensions of the selected mobile device. By this capability of increasing parallax, the optical axes of the cameras relative to each other can also be changed to a greater extent, allowing the longest possible focus of the cameras even without the features of adjustable parallax and convergence control. Furthermore, by separating the refraction and lens functions of the FPLC based camera units 102a, 102b into

discrete refraction units

104a, 104b and

multi-lens block units

106a, 106b, mechanisms such as tele lenses can be incorporated even in the integration of the camera units into modern, thinner mobile devices (such as cell phones/smartphones).

In summary, the present invention provides a

stereoscopic imaging system

100, 200 in which the width/height dimensions of the system are minimized, and thus the described stereoscopic imaging system is readily adaptable to small, thin mobile devices such as smartphones. Because the refractive and lens functions are separated into discrete units contained in the system, a lower profile along the y-axis of the device in which they are contained can be achieved. Further, since the

refraction units

104a, 104b reflect light/images to the plurality of

lens block units

106a, 106b as collimated light beams including parallel light rays, the fields of view of the

refraction units

104a, 104b are independent of any distance between the refraction units and the multi-lens block units. Accordingly, parallax control for the stereoscopic imaging system 100 is possible without moving the plurality of

lens block units

106a, 106b and/or the

image sensors

110a, 110b. This further contributes to the compact design of the described stereoscopic imaging system 100.

The images captured by the

image sensors

110a, 110b, which represent the left and right views, respectively, of the scene may then be processed to provide stereoscopic images and/or image deepened images (i.e., three-dimensional images). Also, it is contemplated to use the described system to provide stereoscopic and/or image plus depth still and video images. Many suitable methods, systems, and computer program products for processing images to provide stereoscopic images and/or image plus depth images are known and contemplated for use herein, including but not limited to the methods described in U.S. patent nos. 8,648,808, 8,964,004, 9,201,519, and 9,310,857, the disclosures of which are incorporated herein by reference in their entirety. The system described, in turn, is readily adaptable to other camera types including, but not limited to, compact dual lens reflex cameras.

Those of ordinary skill in the art will recognize that other embodiments of the present invention are possible without departing from the teachings herein. Thus, the foregoing description has been presented for the purpose of illustrating and describing various aspects of the invention, and those of ordinary skill in the art will recognize that additional embodiments of the present invention are possible without departing from the teachings herein. The detailed description, particularly specific details of the exemplary embodiments, are set forth primarily for the purpose of clarity of understanding and without unnecessary limitations being implied therefrom as such modifications will become apparent to those skilled in the art upon reading the disclosure and may be made without departing from the spirit or scope of the disclosure. Of course, relatively obvious modifications include combining various features of one or more of the drawings with features of one or more other drawings. 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.

This application is a partially continued utility patent application claiming priority from U.S. patent application Ser. No. 16/551,080, filed 8/26/2019, which is a continued patent application claiming the benefit of U.S. patent application Ser. No. 15/591,695, filed 5/10/2017, which in turn claiming priority from U.S. provisional patent application Ser. No. 62/407,754, filed 10/13/2016, the entire disclosure of each of which is incorporated herein by reference.

Claims

1. A stereoscopic imaging system, comprising:

two folded parallel light channel FPLC cells arranged to provide a virtual two-dimensional left side view and a virtual two-dimensional right side view of a scene, each FPLC cell comprising:

a) A fixed lens unit adapted to focus reflected light comprising an image of a scene onto the image sensor, an

b) A refractive unit comprising a reflector adapted to define parallel image reflection paths along an x-axis of the stereoscopic imaging system to the fixed lens unit via a collimated light beam;

wherein the stereoscopic imaging system is adapted to combine the virtual two-dimensional left side view and the virtual two-dimensional right side view into a single three-dimensional image.

2. The stereoscopic imaging system of claim 1, wherein the fixed lens unit and the refractive unit of each FPLC unit are disposed a predetermined separation distance from each other along an x-axis to provide a desired parallax or interocular function for the system.

3. The stereoscopic imaging system of claim 1, wherein the reflector defines a planar reflective surface.

4. A stereoscopic imaging system according to claim 3, further comprising a concave lens disposed between the reflector and the imaging portal of each FPLC cell.

5. The stereoscopic imaging system of claim 4, wherein the concave lens defines a lens field of view that is the same as the field of view of the stationary lens unit.

6. The stereoscopic imaging system of claim 1, wherein the reflector defines an arcuate reflective surface.

7. The stereoscopic imaging system of claim 6, wherein the arcuate reflective surface is configured to define a reflector field of view that is the same as a field of view of the fixed lens unit.

8. The stereoscopic imaging system of claim 1, wherein the fixed lens unit defines a wide angle lens unit or a tele lens.

9. A stereoscopic imaging system, comprising:

b) A refractive unit comprising a planar reflector adapted to define parallel image reflection paths along the x-axis of the stereoscopic imaging system to the fixed lens unit via a collimated light beam;

10. The stereoscopic imaging system of claim 9, wherein the fixed lens unit and the refractive unit of each FPLC cell are disposed a predetermined separation distance from each other along the x-axis to provide a desired parallax or interocular function for the system.

11. The stereoscopic imaging system of claim 9, further comprising a concave lens disposed between the planar reflector and the imaging portal of each FPLC cell.

12. The stereoscopic imaging system of claim 11, wherein the concave lens defines a lens field of view that is the same as the field of view of the stationary lens unit.

13. The stereoscopic imaging system of claim 9, wherein the fixed lens unit defines a wide angle lens or a tele lens.

14. A stereoscopic imaging system, comprising:

b) A refractive unit comprising a convex reflector adapted to define parallel image reflection paths along the x-axis of the stereoscopic imaging system to the fixed lens unit via a collimated light beam;

15. The stereoscopic imaging system of claim 14, wherein the fixed lens unit and the refractive unit of each FPLC unit are disposed a predetermined separation distance from each other along an x-axis to provide a desired parallax or interocular function for the system.

16. The stereoscopic imaging system of claim 14, further comprising a concave lens disposed between the convex reflector and the imaging portal of each FPLC cell.

17. The stereoscopic imaging system of claim 14, wherein the convex reflector is configured to define a reflector field of view that is the same as a field of view of the fixed lens unit.

18. The stereoscopic imaging system of claim 14, wherein the fixed lens unit defines a wide angle lens or a tele lens.