Illumination for Zonal Time-of-Flight Imaging

Abstract

A zoned time-of-flight (ToF) arrangement includes a sensor and a steerable light source that produces an illumination beam having an angular range that is less than a field of view (FoV) of the sensor. The illumination beam is steerable within the sensor's FoV to optionally move through the sensor's FoV or to reside in a specific region of interest. Steering the illumination beam and subsequently generating a depth map of the illuminated area permits advantageous operation of the ToF arrangement by simultaneously illuminating the entire sensor's FoV. For example, ambient performance, maximum range, and jitter are improved. A variety of steering alternative configurations are disclosed, including mechanical, electro-optical, and electrowetting solutions.

Description

Background Art

[0001] Three-dimensional (3D) time-of-flight (ToF) cameras use a cost-effective pixel array and an active modulated light source to provide 3D imaging for applications including gesture detection and 3D scanning. The ToF camera illuminates a scene, senses the reflected light, and converts the phase-shift data into distance. In some examples, a solid-state laser or LED operating in the near-infrared range (~850 nm) provides illumination, and a sensor responsive to the same spectrum is used. The light picked up by the sensor has an ambient component and a reflected signal component. The distance (depth) information is only available in the reflected component, and thus the ambient component is noise.

[0002] When the power density of the ambient component is high relative to the power density of the reflected component, the signal-to-noise ratio (SNR) is affected, which may lead to degradation of distance accuracy and range. One solution is to narrow the field of view (FoV) of the ToF camera, which requires scanning the FoV to capture the entire scene. An alternative solution is to increase the illumination power, which increases power consumption and requires a more expensive light source. Both solutions have drawbacks. Summary of the Invention

[0003] The disclosed examples are described in detail below with reference to the following listed drawings. The following summary of the invention is provided to illustrate some of the examples disclosed herein. However, this does not mean that all examples are limited to any specific configuration or order of operations.

[0004] Some aspects disclosed herein relate to a system for zoned time-of-flight imaging, the system including an illumination module, the illumination module including: a light source; a diffusing element operable to diffuse light emitted from the light source; and a directing element operable to direct the light emitted from the light source, wherein the diffusing element and the directing element are configured such that the light emitted from the light source passes through the diffusing element and is directed by the directing element as an illumination beam in a defined direction. Brief Description of the Drawings

[0005] The disclosed examples are described in detail below with reference to the following listed drawings:

[0006] Figure 1 is a block diagram of an example zoned time-of-flight (ToF) imaging arrangement;

[0007] Figure 2 is a diagram of another example zoned ToF imaging arrangement;

[0008] Figure 3 is a diagram of an example zoned ToF illumination module;

[0009] Figure 4 is a diagram of another example ToF illumination module;

[0010] Figure 5A is a diagram of another example ToF illumination module;

[0011] Figure 5B is one that can be used with Figure 5A top view of a segmented optical diffuser that can be used with the ToF illumination module;

[0012] Figure 6 is a diagram of another example ToF illumination module;

[0013] Figure 7 is a diagram of another example ToF illumination module;

[0014] Figure 8 is a diagram of another example ToF illumination module;

[0015] Figure 9 is a diagram of another example ToF illumination module;

[0016] Figure 10 is a diagram of an example segmented ToF imaging arrangement for generating a depth map;

[0017] Figure 11 is a flowchart illustrating exemplary operations involved in segmented ToF imaging that can be used with any arrangement in the Figures 1 - 10 arrangement;

[0018] Figure 12 is a block diagram of an example computing environment suitable for implementing some of the various examples disclosed herein;

[0019] Throughout the figures, corresponding reference numerals indicate corresponding parts. Detailed Description

[0020] Various examples will be described in detail with reference to the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts. However, the references associated with specific examples and implementations throughout this disclosure are provided for illustrative purposes only and do not imply a limitation on all examples unless otherwise indicated.

[0021] Three-dimensional (3D) time-of-flight (ToF) cameras use a cost-efficient pixel array and an active modulated light source to provide 3D imaging for applications including gesture detection and 3D scanning. The ToF camera illuminates a scene, senses the reflected light, and converts the phase-shift data into distance. In some examples, a solid-state laser or LED operating in the near-infrared range (~850 nm) provides illumination, and a sensor responsive to the same spectrum is used. The light picked up by the sensor has an ambient component and a reflected signal component. The distance (depth) information is available only in the reflected component, and thus the ambient component is noise.

[0022] When the power density of the ambient component is high relative to the power density of the reflected component, the signal-to-noise ratio (SNR) is affected, which may lead to a degradation in distance accuracy and range.

[0023] Accordingly, a partitioned ToF arrangement is introduced that includes a sensor and a steerable light source that generates an illumination beam having an angular range less than the FoV of the sensor, thereby providing a greater power density for the same peak laser. The illumination beam is steerable within the FoV of the sensor to optionally move through the FoV of the sensor or reside in a particular region of interest. Steering the illumination beam, and subsequently generating a depth map of the illuminated region, permits advantageous operation of illuminating the entire sensor FoV simultaneously through the ToF arrangement. For example, ambient performance, maximum range, and jitter are improved. A variety of steering alternative configurations are disclosed, including mechanical, electro-optical, microelectromechanical systems (MEMS), and electrowetting prisms. The steering techniques in various embodiments depend on system and application size, power consumption, frequency, angle, position repeatability, and drive voltage requirements, as further described herein. Although in some examples, moving the illumination beam through the FoV of the sensor can be accomplished by raster scanning, many examples will reside in certain regions of interest, or at least move based on scene content.

[0024] The region containing the object of interest can be selectively illuminated instead of illuminating the entire FoV of the sensor. Different operating modes can include moving through the FoV and dwelling in a particular region for an additional imaging period. This allows for more efficient use of the laser and, with a smaller illuminated area, can save power. Alternatively, for the same power level, there will be more intense illumination since the light is more focused. This can compensate for the effects of high ambient light levels and improve the SNR. Also, for the same power level, a longer range for depth imaging can be supported since the more intense illumination compensates for beam divergence at greater distances. In this way, the optical architecture proposed in the present disclosure provides a compact, low-cost solution that supports advantageous zoned ToF operation. In some examples, different regions of the sensor's FoV are imaged with different exposure times, or to compensate for directionally dependent light sources for ambient light, based on bright and dark objects in the same scene. This is a way to customize the dynamic range of the illuminated region.

[0025] Figure 1 is a block diagram of an example zoned time-of-flight (ToF) imaging arrangement that includes a zoned ToF imager 100. The ToF imager 100 includes an illumination module 102 and a sensor module 202. The illumination module 102 generates an illumination beam 106 having an angular range 104, and the sensor module 202 has a FoV 206 with an angular range 204. The illumination beam 106 has an angular range 104 that is less than the angular range 204 of the sensor FoV 206. Thus, the sensor module 202 has a FoV 206 with an angular range 204 that is larger than the angular range 104 of the illumination beam 106. It should be understood that Figure 1 is a side view, and the ToF imager 100 operates in a 3D environment. In some examples, the FoV 206 of the sensor module 202 has an angular range 204 in each of two dimensions (azimuth and elevation), and the angular range 204 is a multiple (e.g., three times wider) of the angular range 104 of the illumination beam 106. For example, if the FoV 206 extends 120 degrees in each azimuth and elevation, the illumination beam 106 extends 40 degrees as measured according to the common 3dB beam width measurement convention.

[0026] In a ToF arrangement, distances are measured for pixels in a two-dimensional (2D) addressable array, resulting in a depth map. The depth map is a collection of 3D points or voxels. In some examples, a 2D representation of the depth map is a grayscale image, where higher brightness indicates closer voxels. In some examples, the depth map can be plotted as a collection of points or a point cloud in 3D space. ToF is useful for scene understanding, such as recognizing gestures, which requires segmenting the subject of interest (foreground) to distinguish it from the rest of the image (background).

[0027] Both the illumination module 102 and the sensor module 202 are coupled to a Time-of-Flight Controller (TFC) 1200a. Some examples of the TFC 1200a include a computing device 1200, which is described in more detail with reference to Figure 12 The TFC 1200a synchronizes the operation of the illumination module 102 with the operation of the sensor module 202, including controlling the modulation of the light and imaging periods, directing the illumination beam 106, and combining with the sensor module 202 to generate a depth map (see Figure 10 ). In some examples, the sensor module 202 incorporates some or all of the TFC 1200a. In some examples, the point cloud data stored on the TFC 1200a can be accessed by an external node for additional processing.

[0028] Figure 2 is a diagram of another example partitioned ToF imaging arrangement, showing an exemplary layout of the ToF imager 100. It should be understood that Figure 2 and other figures in this document are not necessarily drawn to scale, and for illustrative purposes, some dimensions may be exaggerated or compressed. As explained with respect to Figure 1 both the illumination module 102 and the sensor module 202 are coupled to the TFC 1200a. The illumination module 102 includes a light source 110 that generates a light beam 112, which is focused by a focusing element 114 onto a guiding element 116 that is operable to direct the light emitted from the light source 110 such that the light is directed as an illumination beam 106 in a defined direction.

[0029] The sensor module 202 has a sensor element 210 and a lens 214 that focuses the light that has been emitted from the light source 110 and then reflected from an imaging scene within the FoV 206 onto the operating sensor element 210. The sensor module 202 is thus able to sense the light emitted from the light source 110 and reflected from the scene, and then is also able to (either in conjunction with the TFC 1200a or by incorporating the functionality of the TFC 1200a) use the sensed light to generate a depth map for at least the illuminated area within the FoV 206.

[0030] Figure 3 is a diagram of an example partitioned ToF illumination module 102a, which is the illumination module 102 ( Figure 1 and Figure 2) a version of. The lighting module 102a includes a light source 110; a collimating element 302, a diffusing element 304, a focusing element 306, and a guiding element 308. The light source 110, the collimating element 302, the diffusing element 304, the focusing element 306, and the guiding element 308 are arranged in the order in which the emitted light encounters them as: the first light source 110, then the collimating element 302, then the diffusing element 304, then the focusing element 306, and then the guiding element 308.

[0031] In operation, a light beam 300a is emitted from the light source 110 and impinges on the collimating element 302. The collimating element 302 operates to collimate the light emitted from the light source 110, converting the light beam 300a into a collimated light beam 300b. The collimated light beam 300b impinges on the diffusing element 304, forming an illumination profile. The diffusing element 304 is operable to diffuse the light emitted from the light source 110, thereby converting the collimated light beam 300b into a diffused light beam 300c. The diffusing element 304 provides eye safety, a desired angular range, and / or a desired beam profile (e.g., a uniform or Gaussian power profile). The diffused light beam 300c impinges on the focusing element 306, and the focusing element 306 forms an image of the diffusing element 304 on the guiding element 308 via a focused light beam 300d. In some examples, the guiding element 308 includes a movable mirror, providing a mechanical guiding assembly. Focusing the light rays permits the use of a smaller mirror. In some examples, the mirror is flat to avoid phase distortion of the light wavefront. In some examples, the mirror has an optical profile for focusing. Ensuring a specific surface profile over a larger surface is generally more expensive. Additionally, a smaller mirror can generally be guided faster and requires less power to move. Thus, focusing of the light provides cost and operational advantages.

[0032] The guiding element 308 is operable to guide the light emitted from the light source 110, thereby guiding the focused light beam 300d into a guided illumination beam 106a (guided towards a first illuminated area) and a guided illumination beam 106b (guided towards a second illuminated area). In this arrangement, the collimating element 302, the diffusing element 304, and the guiding element 308 are configured such that the light emitted from the light source 110 passes through the collimating element 302 and the diffusing element 304 and is guided by the guiding element 308 into a guided illumination beam (106a or 106b) in a defined direction. In some examples, the TFC 1200a controls the guiding element 308. In some examples, the TFC 1200a is incorporated within the sensor module 202.

[0033] Representative dimensions of an exemplary version of the illumination module 102a are: D1 is 2 millimeters (mm); D2 is 1 mm; D3 and D4 are 15 mm (the focal length of the focusing element 306), and D5 is 1 mm or less. In some examples, the focusing element 306 is a biconvex lens, where f = 7.5 mm. In some examples, the guiding element 308 moves in only a single dimension, and in other examples, the guiding element 308 moves in two dimensions (up / down and in / out in the Figure 3 plane). A static folding mirror can be placed between the collimating element 302 and the diffusing element 304.

[0034] Figure 4 is a diagram of an exemplary partitioned ToF illumination module 102b, which is a version of the illumination module 102( Figure 1 and Figure 2 ). The illumination module 102b includes a light source 110, a focusing element 306, a first guiding element 410 or translation element, a collimating element 302, a diffusing element 304, and a second guiding element 408. The second guiding element 408 is stationary in that it does not move; rather, based on the position on the second guiding element 408 where light impinges, the second guiding element 408 directs the light by refracting it into different angular directions. The illustrated elements are arranged in the order in which the emitted light encounters them: light source 110, focusing element 306, first guiding element 410, collimating element 302, diffusing element 304, and second guiding element 408. In some examples, the first guiding element 410 includes a movable mirror (e.g., a micromirror). In such examples, the mirror does not act as a guiding element for the ultimately transmitted illumination beams 106a and 106b, but rather translates the light laterally (one- or two-dimensionally) across the collimating element 302. To achieve this, the first guiding element 410 (inside the ToF illumination module 102b) directs the light to strike a specific portion of the collimating element 302 such that after passing through the collimating element 302, the light strikes a portion of the second guiding element 408 that refracts the beam to shape and direct the beam as desired. In some examples, the mirror used as the first guiding element 410 in the illumination module 102b can be made smaller than the mirror used as the guiding element 308 in the illumination module 102a. In some examples, a film with optical power (e.g., a Fresnel surface) can be added to the first guiding element 410.

[0035] In operation, a light beam 300a is emitted from a light source 110 and impinges on a focusing element 306, which focuses an image of the light source 110 onto a first guiding element 410 via a focused light beam 400a. In some examples, the TFC 1200a controls the first guiding element 410; in some examples, the TFC 1200a is incorporated within the sensor module 202. The focused light beam 400a is redirected as a translated light beam 400b or a translated light beam 400e by moving the first guiding element 410. The translated light beam 400b passes through a collimating element 302, which is operable to collimate light, converting the translated light beam 400b into a collimated light beam 400c. The collimated light beam 400c impinges on a diffusing element 304, which is operable to diffuse light, thereby converting the collimated light beam 400c into a diffused light beam 400d. The diffused light beam 400d impinges on a second guiding element 408. The second guiding element 408 is operable to direct light, thereby guiding the diffused light beam 400d into a directed illumination light beam (106a) that is directed toward a first illuminated area. Although laterally translated, a similar path causes the translated light beam 400e to pass through the collimating element 302 to become a collimated light beam 400f, then through the diffusing element 304 to become a diffused light beam 400g, and then ultimately through the second guiding element 408 to become a directed illumination light beam (106b) that is directed toward the first illuminated area. In this arrangement, the collimating element 302, the diffusing element 304, and the second guiding element 408 are configured such that light emitted from the light source 110 passes through the collimating element 302 and the diffusing element 304 and is directed by the second guiding element 408 into a directed illumination light beam (106a or 106b) in a defined direction.

[0036] In some examples, the second guiding element 408 includes a refractive lens (e.g., Fresnel, prism, etc.) having a non-uniform surface that directs or guides light in different directions based on the lateral position at which the light impinges. Thus, for the purpose of directing the illumination light beam (106a or 106b), the first guiding element 410 is utilized to horizontally translate the light, causing different refraction angles of the light passing through the second guiding element 408. The translated light beam 400b and the translated light beam 400e are divergent light beams collimated by the collimating element 302 to permit a version of the light that impinges on the diffusing element 304 at nearly normal incidence. In some examples, the ToF illumination module 102b can advantageously use fewer mirrors than the ToF illumination module 102a because the image of the light source 110 focused onto the first guiding element 410 can be smaller than the image of the diffusing element 304 formed on the guiding element 308. Figure 3 than) the ToF illumination module 102a because the image of the light source 110 focused onto the first guiding element 410 can be smaller than the image of the diffusing element 304 formed on the guiding element 308.

[0037] Figure 5Ais a diagram of an exemplary ToF illumination module 102c, which is a version of the illumination module 102 of ( Figure 1 and Figure 2 ). The illumination module 102c includes a light source 110, a collimating element 302, a guiding element 308, and a diffusing element 504. They are arranged in the order in which the emitted light encounters them: the light source 110, the collimating element 302, the guiding element 308, and the diffusing element 504. The diffusing element 504 and the guiding element 308 are configured such that the light emitted from the light source 110 passes through the diffusing element 504 and is guided by the guiding element 308 into an illumination beam in a defined direction, although in the illumination module 102c, the light encounters the guiding element 308 before encountering the diffusing element 504. In some examples, the guiding element 308 includes a mirror. In some examples, the TFC 1200a controls the guiding element 308; in some examples, the TFC 1200a is incorporated within the sensor module 202.

[0038] In operation, a light beam 300a is emitted from the light source 110 and impinges on the collimating element 302, which is operable to collimate the light, converting the light beam 300a into a collimated light beam 500a. The collimated light beam 500a impinges on the guiding element 308, which is operable to guide the light, thereby guiding the collimated light beam 500a into a guided light beam 500b or a guided light beam 500c. The guided light beam 500b passes through the diffusing element 504 to become a guided illumination beam 106a (guided towards a first illuminated area). The guided light beam 500c passes through the diffusing element 504 to become a guided illumination beam 106b (guided towards a first illuminated area).

[0039] Figure 5A The diffusing element 504 is shown from the side, while Figure 5B is a top view of the diffusing element 504. In the example shown in Figure 5A and 5B , the diffusing element 504 includes a segmented optical diffuser. As can be seen from Figure 5B , the diffusing element 504 is divided into nine segments (regions), which are identified as Z1 - Z9. Due to the guiding, in the case of some angles deviating from the normal, the light impinging on the diffusing element 504 is substantially perpendicular to Figure 5Bis incident on the diffuser element 504 in a plane. Each of the segments Z1-Z9 provides a diffractive optical element designed for a specific angle of incidence. This permits separating the collimating element 302 from the diffuser element 504 and placing the steering element 308 therebetween. In some examples, instead, the collimating element 302 may narrowly focus the light such that a smaller mirror may be used as the steering element 308 rather than the collimating element 302 producing fully collimated light. In some examples, the diffuser element 504 compensates for partially collimated light.

[0040] Figure 6 is a diagram of an example ToF illumination module 102d, which is a version of the illumination module 102 of ( Figure 1 and Figure 2 ). The illumination module 102d is similar to the illumination module 102c, except that a domed optical diffuser is used as the diffuser element 604 instead of the segmented optical diffuser used for the diffuser element 504. With a dome configuration of the diffuser element 604 that can be domed in two dimensions ( Figure 6 in the plane of up / down and in / out), light impinges on each part of the diffuser element 604 at near-normal incidence. Although the domed nature of the diffuser element 604 is illustrated as segmented flat segments, some examples of the diffuser element 604 have curvature in the dome structure. The domed optical diffuser may also be three-dimensional (e.g., polyhedral).

[0041] The illumination module 102d includes a light source 110, a collimating element 302, a steering element 308, and a diffuser element 604. They are arranged in the order in which the emitted light encounters them: the light source 110, the collimating element 302, the steering element 308, and the diffuser element 604. The diffuser element 604 and the steering element 308 are configured such that the light emitted from the light source 110 passes through the diffuser element 604 and is directed by the steering element 308 into an illumination beam in a defined direction, although in the illumination module 102d, the light encounters the steering element 308 before it encounters the diffuser element 604. In some examples, the steering element 308 includes a mirror. In some examples, the TFC 1200a controls the steering element 308; in some examples, the TFC 1200a is incorporated within the sensor module 202.

[0042] In operation, a light beam 300a is emitted from a light source 110 and impinges on a collimating element 302, which is operable to collimate the light, converting the light beam 300a into a collimated light beam 500a. The collimated light beam 500a impinges on a steering element 308, which is operable to steer the light, thereby guiding the collimated light beam 500a into a steered light beam 500b or a steered light beam 500c. In some examples, alternatively, the collimating element 302 may narrowly focus the light such that a smaller mirror may be used as the steering element 308 instead of the collimating element 302 producing fully collimated light. In some examples, a diffusing element 604 compensates for the partially collimated light. The steered light beam 500b passes through the diffusing element 604 to become a steered illumination light beam 106a (directed toward a first illuminated area). The steered light beam 500c passes through the diffusing element 604 to become a steered illumination light beam 106b (directed toward the first illuminated area).

[0043] Figure 7 is a diagram of an example ToF illumination module 102e, which is a version of the illumination module 102 of ( Figure 1 and Figure 2 ). The illumination module 102e includes a light source 110, a collimating element 302, a steering element 708, and a diffusing element 504. They are arranged in the order in which the emitted light encounters them as: the light source 110, the collimating element 302, the steering element 708, and the diffusing element 504. The diffusing element 504 and the steering element 708 are configured such that light emitted from the light source 110 passes through the diffusing element 504 and is steered by the steering element 708 into an illumination light beam in a defined direction, although in the illumination module 102e, the light encounters the steering element 708 before encountering the diffusing element 504.

[0044] In some examples, the steering element 708 includes a switchable polarization grating, providing an electro-optical steering assembly. In some examples, a TFC 1200a controls the steering element 708. In some examples, the TFC 1200a is incorporated within the sensor module 202. In the illustrated example, the illumination module 102e further includes a folding mirror 710. The folding mirror 710 is used when the manufacturing options of the illumination module 102e tend to orient the light source 110 in a different plane from the intended illumination direction. For example, manufacturing a laser that produces a light beam parallel to the circuit board may be more cost-effective, even if the intended illumination direction is primarily perpendicular to the plane of the circuit board.

[0045] In operation, a light beam 300a is emitted from a light source 110 and impinges on a collimating element 302, which is operable to collimate the light, converting the light beam 300a into a collimated light beam 500a. The collimated light beam 500a impinges on a folding mirror 710, which redirects the light as a redirected light beam 700a towards a guiding element 708. In some examples, instead, the collimating element 302 may narrowly focus the light such that a smaller folding mirror 710 may be used rather than the collimating element 302 producing fully collimated light. The guiding element 708 guides the redirected light beam 700a into a guided light beam 700b or a guided light beam 700c. The guided light beam 700b passes through a diffusing element 504 to become a guided illumination light beam 106a (directed towards a first illuminated area). The guided light beam 700c passes through the diffusing element 504 to become a guided illumination light beam 106b (directed towards a second illuminated area).

[0046] Figure 8 is a diagram of an example ToF illumination module 102f, which is a version of the illumination module 102 of ( Figure 1 and Figure 2 ). The illumination module 102f includes a light source 110, a collimating element 302, a diffusing element 304, and a guiding element 808. They are arranged in the order in which the emitted light encounters them as: light source 110, collimating element 302, mirror, diffusing element 304, guiding element 808. The diffusing element 304 and the guiding element 808 are configured such that light emitted from the light source 110 passes through the diffusing element 304 and is guided by the guiding element 808 as an illumination light beam in a defined direction.

[0047] In some examples, the guiding element 808 includes a switchable polarization grating providing electro-optical guidance. In some examples, a TFC 1200a controls the guiding element 808. In some examples, the TFC 1200a is incorporated within the sensor module 202. In the illustrated example, the illumination module 102f also includes an optional folding mirror 710, which is used when the manufacturing options of the illumination module 102f tend to orient the light source 110 in a different plane from the intended illumination direction.

[0048] In operation, a light beam 300a is emitted from a light source 110 and impinges on a collimating element 302, which is operable to collimate the light, converting the light beam 300a into a collimated light beam 500a. The collimated light beam 500a impinges on a folding mirror 710, which redirects the light as a redirected light beam 700a towards a diffusing element 304. The element 304, which is operable to diffuse the light, converts the redirected light beam 700a into a diffused light beam 800a. The diffused light beam 800a impinges on a directing element 808. The directing element 808 is operable to direct the light, thereby guiding the diffused light beam 800a into a directed illumination light beam 106a (directed towards a first illuminated area) or a directed illumination light beam 106b (directed towards a second illuminated area).

[0049] Figure 9 is a diagram of an example ToF illumination module 102g, which is a version of the illumination module 102 of ( Figure 1 and Figure 2 ). The illumination module 102g includes a light source 110, a collimating element 302, a diffusing element 304, and a directing element 908. They are arranged in the order in which the emitted light encounters them as: light source 110, collimating element 302, mirror, diffusing element 304, directing element 908. The diffusing element 304 and the directing element 908 are configured such that light emitted from the light source 110 passes through the diffusing element 304 and is directed by the directing element 908 as an illumination light beam in a defined direction.

[0050] In some examples, the directing element 908 includes a liquid crystal lens (e.g., a pair of liquid crystal lenses), and in some versions, the directing is provided by electrowetting a guiding solution (electrowetting component). The directing element 908 is illustrated as a set of tandem lens arrays 908a and 908b. In some examples of the lens arrays 908a and 908b, the microlens arrays are suspended in a liquid crystal that can be electrically adjusted to direct the light. In some examples of the lens arrays 908a and 908b, the horizontal translation of the lens array 908a relative to the lens array 908b directs the light. In some examples, a TFC 1200a controls the directing element 908. In some examples, the TFC 1200a is incorporated within the sensor module 202. In the illustrated example, the illumination module 102g also includes an optional folding mirror 710, which is used when the manufacturing options of the illumination module 102g tend to orient the light source 110 in a plane different from the intended illumination direction.

[0051] In operation, a light beam 300a is emitted from a light source 110 and impinges on a collimating element 302, which is operable to collimate the light, converting the light beam 300a into a collimated light beam 500a. The collimated light beam 500a impinges on a folding mirror 710, which redirects the light as a redirected light beam 700a towards a diffusing element 304. The element 304, which is operable to diffuse light, converts the redirected light beam 700a into a diffused light beam 800a. The diffused light beam 800a impinges on a guiding element 808. The guiding element 908 is operable to guide the light, thereby guiding the diffused light beam 800a into a guided illumination light beam 106a (guided towards a first illuminated region) or a guided illumination light beam 106b (guided towards a second illuminated region).

[0052] Figure 10 is a diagram of an example partitioned ToF imaging arrangement that utilizes a ToF imager 100 to generate a depth map 1002 of a scene 1004. In some examples, the ToF imager 100 calculates the depth for each pixel in the depth map 1002, which involves anti-aliasing. As previously described (see Figure 1 and Figure 2 ), the ToF imager 100 includes a sensor module 202 that is operable to generate a depth map 1002 of the scene 1004 within at least a portion of a sensor FoV 206 by sensing light that is emitted from the light source 110 and reflected from the scene 1004. That is, the ToF imager 100 is capable of imaging any part of the scene 1004 within an angular range 204 of the FoV 206. In some examples, the sensor module 202 uses the internal functionality of the TFC 1200a to generate the depth map 1002. In some examples, the sensor module 202 uses the external functionality of the TFC 1200a in combination with the TFC 1200a to generate the depth map 1002.

[0053] As Figure 10 shown, the illumination light beam 106 illuminates an area of the FoV 206. Thus, the illumination light beam 106 can be the guided illumination light beam 106a ( Figures 3 - 9 of) or the guided illumination light beam 106a. One advantage of imaging only the area within the FoV 206 is that the dynamic range of the ToF imager 100 can be customized for the conditions within the illuminated region (e.g., a customized response based on ambient light and distance conditions).

[0054] Figure 11 is an illustration of what can be associated with Figures 1 - 10Flowchart of exemplary operations involved in partitioned ToF imaging for use in conjunction with any arrangement in the arrangement of. In operation 1102, light is emitted from a light source (e.g., light source 110), and operation 1104 includes collimating at least in part the light emitted from the light source. Operation 1106 includes diffusing the light emitted from the light source, and operation 1108 includes focusing the light. In some examples, operation 1108 involves forming an illumination profile on a guiding element, while in some examples, operation 1108 involves focusing an image of the light source onto the guiding element. Operation 1110 then includes using the guiding element to direct the illumination beam to a selected region within the field of view of the sensor. It should be understood that operations 1104 - 1110 can occur in a different order; according to various examples described herein, some of operations 1104 - 1108 can be omitted, and some of operations 1104 - 1110 can be combined.

[0055] In some examples, guiding includes illuminating different segments of a segmented diffuser. In some examples, guiding includes moving a mirror. In some examples, guiding includes irradiating at least one element selected from the list consisting of a refractive lens, a polarization grating, and a liquid crystal lens. In the case of any of these items, operation 1110 includes using the guiding element to direct the illumination beam to a selected region within the field of view of the sensor module, wherein the field of view of the sensor module has an angular range greater than that of the illumination beam, and wherein the illumination beam includes the light emitted from the light source. In a first pass through operation 1110, the selected region is a first region within the field of view of the sensor module.

[0056] Operation 1112 includes customizing the dynamic range for the illuminated region. One way to achieve this is by adjusting the illumination power (e.g., the power of the light emitted from the light source). Another way to achieve this is to customize the exposure time for different regions of the FoV of the sensor. For example, the exposure time in a particular illuminated region can be based on bright and dark objects within that region, or be set to compensate for direction - dependent light sources of ambient light. Thus, there are various ways to customize the dynamic range for the illuminated region. Operation 1114 includes using the sensor module to sense the light emitted from the light source and reflected from the scene, and operation 1116 includes using the sensed light to generate a depth map for at least the illuminated region. In a first pass through operation 1110, the illuminated region is the first region.

[0057] Operation 1120 includes determining the next region of interest for illumination and imaging. Instead of illuminating the entire sensor's FoV, a region containing the object of interest can be selectively illuminated. In some examples, certain passes through operation 1120 include avoiding directing the illumination beam to a second region within the FoV of the sensor module to save power. Different operating modes can include moving through the FoV and dwelling for additional imaging periods at specific regions. This allows for more efficient use of the laser, as power may be saved with a smaller illuminated area. Alternatively, for the same power level, there will be stronger illumination as the light is more focused. This can compensate for the effects of high ambient light levels and improve the SNR. Also, for the same power level, a longer range for depth imaging can be supported as the stronger illumination compensates for beam divergence at greater distances. In this way, the optical architecture proposed in the present disclosure provides a compact, low-cost solution that supports advantageous zonal ToF operation. Decision operation 1122 determines whether the illumination module will dwell in the same region.

[0058] If decision operation 1122 determines that the illumination module will dwell in the same region, the illumination beam will remain for an additional imaging period in the first region before returning to operation 1110 as flowchart 1100 directs the illumination beam to a second region within the FoV of the sensor module. However, if decision operation 1122 determines that the illumination module will not dwell in the same region, operation 1110 includes using the directing element to direct the illumination beam to a second region within the FoV of the sensor module. Continuing, operation 1112 includes customizing the dynamic range for the second region. In this way, different dynamic ranges can be used for different regions within the same sensor FoV, such as by using different illumination powers and / or different exposure (integration) times. Operation 1114 includes using the sensor module to sense the light emitted from the light source and reflected from the scene, and operation 1116 includes using the sensed light to generate a depth map for at least the second region. In a second or subsequent pass, operation 1118 includes generating a composite depth map by combining depth maps for different regions (e.g., different regions illuminated during multiple passes through operations 1110 - 1116).

[0059] Additional examples

[0060] Some aspects and examples disclosed herein relate to a system for zonal time-of-flight imaging, including an illumination module that includes: a light source; a diffusing element operable to diffuse light emitted from the light source; a directing element operable to direct light emitted from the light source, wherein the collimating element, diffusing element, and directing element are configured such that light emitted from the light source passes through the collimating element and the diffusing element and is directed by the directing element as an illumination beam in a defined direction.

[0061] Additional aspects and examples disclosed herein relate to a system for zonal time-of-flight imaging, including an illumination module and a sensor module: The illumination module includes: a light source; a collimating element operable to collimate light emitted from the light source; a diffusing element operable to diffuse light emitted from the light source; and a directing element operable to direct light emitted from the light source, wherein the collimating element, the diffusing element, and the directing element are configured such that light emitted from the light source passes through the collimating element and the diffusing element and is directed by the directing element as an illumination beam in a defined direction; wherein the directing element includes at least one element selected from the list consisting of: a mirror, a refractive lens, a polarization grating, a liquid crystal lens; The sensor module is operable to generate a depth map of a scene within at least a portion of a sensor field of view by sensing light emitted from the light source and reflected from the scene, wherein the field of view of the sensor module is a multiple of the angular extent of the illumination beam in each of two dimensions, and wherein the illumination beam is steerable within the field of view of the sensor module.

[0062] Additional aspects and examples disclosed herein relate to a process for zonal time-of-flight imaging, including: using a directing element to direct an illumination beam to a first region within the field of view of a sensor module, wherein the sensor module has a field of view with an angular extent greater than that of the illumination beam, and wherein the illumination beam includes light emitted from a light source; diffusing light emitted from the light source; using the sensor module to sense light emitted from the light source and reflected from the scene; and using the sensed light to generate a depth map for at least the first region.

[0063] Alternatively, or in addition to the other examples described herein, examples include any combination of the following:

[0064] - A sensor module operable to generate a depth map of a scene within at least a portion of a sensor field of view by sensing light emitted from a light source and reflected from the scene;

[0065] - The sensor module has a field of view with an angular extent greater than that of the illumination beam, and wherein the illumination beam is steerable within the field of view of the sensor module;

[0066] - The field of view of the sensor module is a multiple of the angular extent of the illumination beam in each of two dimensions;

[0067] - The illumination module further includes a collimating element operable to collimate light emitted from the light source, wherein the collimating element, the diffusing element, and the directing element are configured such that light emitted from the light source passes through the collimating element and the diffusing element and is directed by the directing element as an illumination beam in a defined direction;

[0068] - The illumination module further includes a focusing element, wherein the light source, the collimating element, the diffusing element, the focusing element, and the guiding element are arranged in sequence as: the light source, the collimating element, the diffusing element, the focusing element, and the guiding element;

[0069] - The guiding element includes a mirror;

[0070] - The illumination module further includes a focusing element and a translation element, wherein the light source, the focusing element, the translation element, the collimating element, the diffusing element, and the guiding element are arranged in sequence as: the light source, the focusing element, the translation element, the collimating element, the diffusing element, and the guiding element;

[0071] - The translation element includes a mirror;

[0072] - The guiding element includes a refractive lens;

[0073] - The light source, the collimating element, the guiding element, and the diffusing element are arranged in sequence as: the light source, the collimating element, the guiding element, and the diffusing element;

[0074] - The diffusing element includes a segmented optical diffuser;

[0075] - The diffusing element includes a dome optical diffuser;

[0076] - The guiding element includes a polarization grating;

[0077] - The illumination module further includes a mirror;

[0078] - The light source, the collimating element, the mirror, the diffusing element, and the guiding element are arranged in sequence as: the light source, the collimating element, the mirror, the diffusing element, and the guiding element;

[0079] - The guiding element includes a liquid crystal lens;

[0080] - An illumination profile is formed on the guiding element;

[0081] - Focus the image of the light source onto the guiding element;

[0082] - Guiding includes illuminating different segments of the segmented diffuser;

[0083] - At least partially collimate the light emitted from the light source;

[0084] - Use the guiding element to direct the illumination beam to a second region within the field of view of the sensor module; and use the sensed light to generate a depth map for at least the second region;

[0085] - Before directing the illumination beam to a second region within the field of view of the sensor module, retain the illumination beam in the first region for an additional imaging period;

[0086] - Avoid directing the illumination beam to a second region within the field of view of the sensor module to save power;

[0087] - Generate a synthetic depth map by combining depth maps for different regions;

[0088] And

[0089] - Customize the dynamic range of the illuminated region.

[0090] In some examples, a system for zonal time-of-flight (ToF) imaging includes an illumination module. The illumination module includes: a light source; a diffusing element operable to diffuse light emitted from the light source; and a directing element operable to direct light emitted from the light source. The diffusing element and the directing element are configured such that light emitted from the light source passes through the diffusing element and is directed by the directing element as an illumination beam in a defined direction. The illumination module further includes a collimating element operable to collimate light emitted from the light source. The collimating element, the diffusing element, and the directing element are configured such that light emitted from the light source passes through the collimating element and the diffusing element and is directed by the directing element as an illumination beam in a defined direction. The illumination module further includes a focusing element. The light source, the collimating element, the diffusing element, the focusing element, and the directing element are arranged in sequence from the light source as the collimating element, the diffusing element, the focusing element, and the directing element. The directing element includes a mirror.

[0091] In some examples, a system for zonal time-of-flight (ToF) imaging includes an illumination module. The illumination module includes: a light source; a diffusing element operable to diffuse light emitted from the light source; and a directing element operable to direct light emitted from the light source. The diffusing element and the directing element are configured such that light emitted from the light source passes through the diffusing element and is directed by the directing element as an illumination beam in a defined direction. The illumination module further includes a collimating element operable to collimate light emitted from the light source. The collimating element, the diffusing element, and the directing element are configured such that light emitted from the light source passes through the collimating element and the diffusing element and is directed by the directing element as an illumination beam in a defined direction. The illumination module further includes a focusing element and a translation element. The light source, the focusing element, the translation element, the collimating element, the diffusing element, and the directing element are arranged in sequence from the light source as the focusing element, the translation element, the collimating element, the diffusing element, and the directing element. The translation element includes a mirror.

[0092] In some examples, a system for sectional time-of-flight (ToF) imaging includes an illumination module. The illumination module includes: a light source; a diffusing element operable to diffuse light emitted from the light source; and a guiding element operable to guide the light emitted from the light source. The diffusing element and the guiding element are configured such that the light emitted from the light source passes through the diffusing element and is guided by the guiding element into an illumination beam in a defined direction. The illumination module further includes a collimating element operable to collimate the light emitted from the light source. The collimating element, the diffusing element, and the guiding element are configured such that the light emitted from the light source passes through the collimating element and the diffusing element and is guided by the guiding element into an illumination beam in a defined direction. The illumination module further includes a focusing element and a translation element. The light source, the focusing element, the translation element, the collimating element, the diffusing element, and the guiding element are arranged in sequence starting from the light source as the focusing element, the translation element, the collimating element, the diffusing element, and the guiding element. The guiding element includes a refractive lens.

[0093] In some examples, a system for sectional time-of-flight (ToF) imaging includes an illumination module. The illumination module includes: a light source; a diffusing element operable to diffuse light emitted from the light source; and a guiding element operable to guide the light emitted from the light source. The diffusing element and the guiding element are configured such that the light emitted from the light source passes through the diffusing element and is guided by the guiding element into an illumination beam in a defined direction. The illumination module further includes a collimating element operable to collimate the light emitted from the light source. The collimating element, the diffusing element, and the guiding element are configured such that the light emitted from the light source passes through the collimating element and the diffusing element and is guided by the guiding element into an illumination beam in a defined direction. The light source, the collimating element, the guiding element, and the diffusing element are arranged in sequence starting from the light source as the collimating element, the guiding element, and the diffusing element. The guiding element includes a mirror.

[0094] In some examples, a system for sectional time-of-flight (ToF) imaging includes an illumination module. The illumination module includes: a light source; a diffusing element operable to diffuse light emitted from the light source; and a guiding element operable to guide the light emitted from the light source. The diffusing element and the guiding element are configured such that the light emitted from the light source passes through the diffusing element and is guided by the guiding element into an illumination beam in a defined direction. The illumination module further includes a collimating element operable to collimate the light emitted from the light source. The collimating element, the diffusing element, and the guiding element are configured such that the light emitted from the light source passes through the collimating element and the diffusing element and is guided by the guiding element into an illumination beam in a defined direction. The light source, the collimating element, the guiding element, and the diffusing element are arranged in sequence starting from the light source as the collimating element, the guiding element, and the diffusing element. The guiding element includes a polarization grating. The illumination module further includes a mirror.

[0095] Although aspects of the present disclosure have been described in connection with various examples and their associated operations, those skilled in the art will understand that combinations of operations from any number of different examples are also within the scope of aspects of the present disclosure.

[0096] Examples of the operating environment

[0097] Figure 12 is a block diagram of an example computing device 1200 for implementing aspects disclosed herein and is generally designated as computing device 1200. Computing device 1200 is only one example of a suitable computing environment and is not intended to imply any limitation as to the scope of use or functionality of the examples disclosed herein. Some examples of computing device 1200 include TFC1200a. Computing device 1200 should also not be construed as having any dependency or requirement on any one of the illustrated components / modules or combinations of components / modules. The examples disclosed herein may be described in the general context of computer code or machine-usable instructions, including computer-executable instructions, such as program components, executed by a computer or other machine (such as a personal data assistant or other handheld device). Generally, program components include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types. The disclosed examples may be practiced in a variety of system configurations, including personal computers, laptop computers, smart phones, mobile tablets, handheld devices, consumer electronics, professional computing devices, etc. The disclosed examples may also be practiced in a distributed computing environment when tasks are performed by remote processing devices linked through a communications network.

[0098] Computing device 1200 includes a bus 1210 that directly or indirectly couples the following devices: computer storage memory 1212, one or more processors 1214, one or more presentation components 1216, input / output (I / O) ports 1218, I / O components 1220, power supply 1222, and network components 1224. Computing device 1200 should not be construed as having any dependency or requirement associated with any single one of the components shown therein or combinations of components. Although computing device 1200 is depicted as seemingly a single device, multiple computing devices 1200 may work together and share the depicted device resources. For example, computer storage memory 1212 may be distributed across multiple devices, (multiple) processors 1214 may be located on different devices, and so on.

[0099] Bus 1210 represents what may be one or more buses (such as an address bus, a data bus, or a combination thereof). Although, for clarity, Figure 12The various boxes are shown by lines, but in reality, demarcating the various components is not so clear, and metaphorically, the lines would more accurately be gray and fuzzy. For example, one can consider a rendering component such as a display device as an I / O component. Similarly, the processor has a memory. This is the nature of the art, and to reiterate Figure 12 the illustration is merely an illustration of an exemplary computing device that can be used in conjunction with one or more of the disclosed examples. No distinction is made between categories such as "workstation", "server", "laptop computer", "handheld device", etc., as all of these are contemplated within Figure 12 the scope, and the reference to "computing device" herein. The computer storage memory 1212 can take the form of the following computer storage media references and operably provides a storage means for computer-readable instructions, data structures, program modules, and other data for the computing device 1200. For example, the computer storage memory 1212 can store an operating system, a general application platform, or other program modules and program data. The computer storage memory 1212 can be used to store and access instructions configured to perform the various operations disclosed herein.

[0100] As mentioned below, the computer storage memory 1212 can include computer storage media in the form of volatile and / or non-volatile memory, removable or non-removable memory, data disks in a virtual environment, or a combination thereof. And the computer storage memory 1212 can include any number of memories associated with or accessible by the computing device 1200. The memory 1212 can be inside the computing device 1200 (as Figure 12 shown), outside the computing device 1200 (not shown), or both (not shown). Examples of the memory 1212 include, but are not limited to, random access memory (RAM); read-only memory (ROM); electrically erasable programmable read-only memory (EEPROM); flash memory or other memory technologies; CD-ROM, digital versatile disc (DVD), or other optical or holographic media; cassette tapes, magnetic tapes, disk memories, or other magnetic storage devices; memories wired into an analog computing device; or any other medium for encoding desired information and accessible by the computing device 1200. Additionally or alternatively, the computer storage memory 1212 can be distributed across multiple computing devices 1200, for example, in a virtualized environment where instruction processing is performed on multiple devices 1200. For the purposes of this disclosure, "computer storage media", "computer storage memory", "memory", and "memory device" are synonymous terms for the computer storage memory 1212, and none of these terms include carrier waves or propagated signals.

[0101] (Multiple) processors 1214 may include any number of processing units that read data from various entities, such as memory 1212 or I / O components 1220. Specifically, (multiple) processors 1214 are programmed to execute computer-executable instructions for implementing aspects of the present disclosure. The instructions may be executed by a processor, by multiple processors within computing device 1200, or by a processor external to client computing device 1200. In some examples, (multiple) processors 1214 are programmed to execute instructions such as those illustrated in the flowcharts and depicted in the figures discussed below. Additionally, in some examples, (multiple) processors 1214 represent an implementation of analog techniques for performing the operations described herein. For example, the operations may be performed by an analog client computing device 1200 and / or a digital client computing device 1200. (Multiple) presentation components 1216 present data indications to a user or other device. Exemplary presentation components include display devices, speakers, printing components, vibration components, and the like. Those skilled in the art will appreciate and understand that computer data may be presented in a variety of ways, such as visually in a graphical user interface (GUI), audibly through speakers, wirelessly between computing devices 1200, across wired connections, or otherwise. Ports 1218 allow computing device 1200 to be logically coupled to other devices including I / O components 1220, some of which may be built-in. Example I / O components 1220 include, for example but not limited to, microphones, joysticks, gamepads, satellite dishes, scanners, printers, wireless devices, and the like.

[0102] Computing device 1200 may operate in a networked environment using a logical connection to one or more remote computers via network component 1224. In some examples, network component 1224 includes a network interface card and / or computer-executable instructions (e.g., drivers) for operating the network interface card. Communication between computing device 1200 and other devices may occur using any protocol or mechanism and over any wired or wireless connection. In some examples, network component 1224 is operable to transfer data using a public, private, or hybrid (public and private) transport protocol, transfer data between devices using short-range communication technologies (e.g., near field communication (NFC), Bluetooth TM brand communication, etc.), or a combination thereof. For example, network component 1224 communicates with network 1230 via communication link 1232.

[0103] Although the example computing device 1200 is described, the examples of the present disclosure can be implemented in many other general-purpose or special-purpose computing system environments, configurations, or devices. Examples of well-known computing systems, environments, and / or configurations suitable for use with aspects of the present disclosure include, but are not limited to, smart phones, mobile tablets, mobile computing devices, personal computers, server computers, hand-held or laptop devices, multiprocessor systems, gaming consoles, microprocessor-based systems, set-top boxes, programmable consumer electronics, mobile phones, mobile computing and / or communication devices in the form of wearables or accessories (e.g., watches, glasses, headphones, or earbuds), network PCs, minicomputers, mainframe computers, distributed computing environments including any of the above systems or devices, VR devices, holographic devices, etc. Such systems or devices can receive input from a user in any manner, including from input devices such as keyboards or pointing devices, via gesture input, proximity input (such as by hovering), and / or via voice input.

[0104] Examples of the present disclosure can be described in the general context of computer-executable instructions, such as program modules, being executed by one or more computers or other devices in software, firmware, hardware, or a combination thereof. The computer-executable instructions can be organized into one or more computer-executable components or modules. Generally, program modules include, but are not limited to, routines, programs, objects, components, and data structures that perform particular tasks or implement particular abstract data types. Aspects of the present disclosure can be implemented with any number and organization of such components or modules. For example, aspects of the present disclosure are not limited to the specific computer-executable instructions or the specific components or modules shown in the figures and described herein. Other examples of the present disclosure can include different computer-executable instructions or components that have more or less functionality than those shown and described herein. In examples involving general-purpose computers, aspects of the present disclosure transform the general-purpose computers into special-purpose computing devices when configured to execute the instructions described herein.

[0105] By way of example and not limitation, computer-readable media includes computer storage media and communication media. Computer storage media includes volatile and non-volatile, removable and non-removable memory implemented in any method or technology for storing information such as computer-readable instructions, data structures, program modules, etc. Computer storage media is tangible and mutually exclusive with communication media. Computer storage media is implemented in hardware and does not include carrier waves and propagated signals. Computer storage media for the purposes of this disclosure is not a signal per se. Exemplary computer storage media includes hard disks, flash drives, solid state memories, phase change random access memories (PRAMs), static random access memories (SRAMs), dynamic random access memories (DRAMs), other types of random access memories (RAMs), read only memories (ROMs), electrically erasable programmable read only memories (EEPROMs), flash memory or other memory technologies, compact disc read only memories (CD-ROMs), digital versatile discs (DVDs) or other optical storage devices, cassette tapes, magnetic tapes, magnetic disk storage devices or other magnetic storage devices, or any other non-transmission medium that can be used to store information for access by a computing device. In contrast, communication media typically includes computer-readable instructions, data structures, program modules, etc. in a modulated data signal such as a carrier wave or other transmission mechanism, and includes any information delivery medium.

[0106] The execution or order of execution of the operations in the examples of the present disclosure shown and described herein is not necessary and can be performed in different order manners in various examples. For example, it is within the scope of the aspects of the present disclosure to consider performing or executing a particular operation before, simultaneously with, or after another operation. When introducing elements of aspects of the present disclosure or its examples, the articles "a", "an", "the", and "said" are intended to mean that there is one or more elements. The terms "comprising", "including", and "having" are intended to be inclusive and mean that there may be additional elements in addition to the listed elements. The term "exemplary" is intended to mean "an example of...". The phrase "one or more of the following: A, B, and C" means "at least one of A and / or at least one of B and / or at least one of C".

[0107] Aspects of the present disclosure have been described in detail, and it will be apparent that modifications and variations are possible without departing from the scope of the aspects of the present disclosure as defined in the appended claims. Since various changes can be made to the above-described structures, products, and methods without departing from the scope of the aspects of the present disclosure, all of the content included in the above description and shown in the accompanying drawings should be construed as illustrative rather than restrictive.

Claims

1. A system for zoned time-of-flight (ToF) imaging, the system comprising: Lighting module, comprising: light source; a focusing or collimating element operable to focus or collimate light emitted from the light source; a diffusing element operable to diffuse light emitted from the light source; and a guiding element operable to guide light emitted from the light source, wherein the focusing or collimating element, the diffusing element and the guiding element are configured such that the light emitted from the light source passes through the focusing or collimating element and the diffusing element and is guided by the guiding element into an illumination beam in a defined direction; wherein the guiding element comprises at least one element selected from the group consisting of: a mechanical guiding component, a refractive lens, an electro-optical component, and an electro-wetting component; wherein the focusing or collimating element is located between the light source and the guiding element; and A sensor module operable to generate a depth map of a scene by sensing light emitted from the light source and reflected from the scene within at least a portion of a field of view of the sensor, wherein the sensor module has a field of view having an angular extent greater than the illumination beam, and wherein the illumination beam is steerable within the field of view of the sensor module.

2. A system for zoned time-of-flight (ToF) imaging, the system comprising: Lighting module, comprising: light source; a diffusing element operable to diffuse light emitted from the light source; a collimating element operable to collimate light emitted from the light source, wherein the collimating element is located between the light source and the guide element; and the guide element being operable to guide the light emitted from the light source, wherein the diffusion element and the guide element are configured such that the light emitted from the light source passes through the diffusion element and the collimating element and is guided by the guide element into an illumination light beam in a defined direction; and A sensor module is operable to generate a depth map of the scene by sensing light emitted from the light source and reflected from the scene within at least a portion of a field of view of the sensor.

3. The system of claim 2, wherein the sensor module has a field of view having an angular extent greater than the illumination beam, and wherein the illumination beam is steerable within the field of view of the sensor module. 4 . The system of claim 3 , wherein the sensor module is further operable to generate a composite depth map by combining depth maps for different areas.

5. The system of claim 2, wherein the lighting module further comprises: Focusing element, The light source, the collimating element, the diffusing element, the focusing element and the guiding element are arranged in order starting from the light source: The collimating element, the diffusing element, the focusing element and the guiding element.

6. The system of claim 5, wherein the lighting module further comprises: Translation element, The light source, the focusing element, the translation element, the collimating element, the diffusion element and the guiding element are arranged in order starting from the light source: The focusing element, the translation element, the collimating element, the diffusing element and the guiding element.

7. The system of claim 2, wherein the light source, the collimating element, the guiding element, and the diffusing element are arranged in order from the light source as follows: The collimating element, the guiding element and the diffusing element.

8. The system of claim 7, wherein the diffusing element comprises a segmented optical diffuser or a dome optical diffuser.

9. The system of claim 7, wherein the guiding element comprises a polarization grating.

10. The system of claim 2, wherein the lighting module further comprises: Reflector, The light source, the collimating element, the reflector, the diffusing element and the guiding element are arranged in order starting from the light source: The collimating element, the reflector, the diffusing element and the guiding element.

11. The system of claim 10, wherein the directing element comprises a polarization grating or a pair of liquid crystal lenses.

12. A method for zoned time-of-flight (ToF) imaging, the method comprising: directing an illumination beam to a first area within a field of view of a sensor module using a directing element, wherein the sensor module has a field of view having an angular extent greater than the illumination beam, and wherein the illumination beam comprises light emitted from a light source; focusing or collimating the light sent from the light source before the light reaches the guide element; diffusing the light emitted from the light source; sensing, using the sensor module, light emitted from the light source and reflected from a scene; as well as The sensed light is used to generate a depth map for at least the first area.

13. The method of claim 12, further comprising forming an illumination profile on the guide element.

14. The method of claim 12, further comprising focusing an image of the light source onto the guide element.

15. The method of claim 12, wherein directing comprises illuminating different segments of a segmented diffuser.

16. The method according to claim 12, further comprising: Avoid directing the illumination beam to a second area within the field of view of the sensor module to save power.

17. The method according to claim 12, further comprising: The illumination beam is retained in the first area for an additional imaging period before directing the illumination beam to a second area within the field of view of the sensor module.

18. The method of claim 12, further comprising customizing a dynamic range for the illuminated area.

Images