CAMERAS WITH SCANNING OPTICAL PATH FOLDING ELEMENTS FOR AUTOMOTIVE OR SURVEILLANCE APPLICATIONS

Abstract

Systems including dual-aperture zoom digital cameras with scanning optical path folding elements (OPFEs) for automotive or surveillance applications and methods for operating and using same. In some embodiments, a dual-aperture zoom digital camera comprises a Wide camera with a Wide field of view FOV.sub.W, a Wide sensor and a Wide lens, wherein the Wide camera is operative to output Wide image information, a Tele camera with a Tele field of view FOV.sub.T smaller than FOV.sub.W and with a Tele sensor, a Tele lens with a Tele lens optical axis and a scanning OPFE, and a processing unit operative to detect an object of interest (OOI) from Wide and/or Tele image information and to direct the Tele camera to move FOV.sub.T to acquire Tele image information on the OOI.

Claims

1. A system, comprising: a) a Wide camera with a Wide field of view FOV.sub.W and comprising a Wide sensor and a Wide lens, wherein the Wide camera is operative to output Wide image information; b) a Tele camera with a Tele field of view FOV.sub.T smaller than FOV.sub.W and comprising a Tele sensor, a Tele lens with a Tele lens optical axis and a scanning optical path folding element (OPFE); and c) a processing unit operative to detect an object of interest (OOI) from Wide and/or Tele image information and to direct the Tele camera to move the FOV.sub.T to acquire Tele image information on the OOI.

2. The system of claim 1, wherein the system is installed in a vehicle and wherein the processing unit is further operative to calculate a required measure-of-action or response needed from the vehicle.

3. The system of claim 2, further comprising an actuator to tilt the OPFE to move or scan the FOV.sub.T.

4. The system of claim 2, wherein the processing unit is operative to direct the Tele camera to move the FOV.sub.T to substantially a center of the FOV.sub.W.

5. The system of claim 2, wherein the processing unit is operative to direct the Tele camera to move the FOV.sub.T to substantially a center of the OOI.

6. The system of claim 2, wherein the processing unit is operative to receive steering information from a steering wheel of the vehicle and to direct the Tele camera to move or scan the FOV.sub.T based also on the steering information.

7. The system of claim 3, wherein the processing unit is operative to receive steering information from a steering wheel of the vehicle and wherein the actuator tilts the OPFE to move or scan the FOV.sub.T based also on the steering information.

8. The system of claim 2, wherein the FOV.sub.W covers a road in front of the vehicle, wherein the OOI is a road curve and wherein the processing unit is operative to move the FOV.sub.T to follow the road curve.

9. The system of claim 2, wherein the vehicle comprises a vehicle cabin, wherein the OOI is located inside the vehicle cabin and wherein the OPFE may be tilted to provide an extended Tele camera FOV (FOV.sub.E) greater than FOV.sub.T.

10. The system of claim 2, wherein the OOI is a driver of the vehicle and wherein the required measure-of-action or response is based on a gaze of the driver.

11. The system of claim 2, wherein the OOI is a child and wherein the required measure-of-action or response is a warning that the child does not wear a seat belt.

12. The system of claim 2, wherein the required measure-of-action or response includes a measure-of-action or response selected form the group consisting of changing speed and/or course of the vehicle, operating an internal alarm to a driver of the vehicle, operating an external alarm, sending data information to, or calling Internet/cloud based service/police/road assistance services, and a combination thereof.

13. The system of claim 1, wherein the OOI is a human face.

14. The system of claim 13, wherein the processing unit is operative to instruct the Tele camera to move to a specific location of the human face for face recognition.

15. The system of claim 13, wherein the processing unit is operative to instruct the Tele camera to move FOV.sub.T to scan parts of FOV.sub.W in two directions.

16. The system of claim 15, wherein the scan is performed by the scanning OPFE with a tilting and settling time of the OPFE of between 5-50 msec.

17. The system of claim 1, wherein the processing unit is operative to detect the OOI from Wide and/or Tele image information and to direct the Tele camera to move FOV.sub.T to acquire information on the OOI in automatic tracking mode.

18. The system of claim 1, wherein the Wide and Tele image information may be fused together to form a composite image or a composite video stream.

19. The system of claim 18, wherein each composite image has the same field of view.

20. The system of claim 19, wherein a composite image is formed by stitching a plurality of Tele images.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Non-limiting examples of embodiments disclosed herein are described below with reference to figures attached hereto that are listed following this paragraph. Identical structures, elements or parts that appear in more than one figure are generally labeled with a same numeral in all the figures in which they appear. The drawings and descriptions are meant to illuminate and clarify embodiments disclosed herein, and should not be considered limiting in any way.

[0035] FIG. 1A shows an embodiment of a system disclosed herein;

[0036] FIG. 1B shows an example of elements of a dual-camera in a perspective view;

[0037] FIG. 2 shows schematically a use case of the system of FIG. 1A;

[0038] FIG. 3 shows a flow chart of a method in the use case of FIG. 2;

[0039] FIG. 4A shows another embodiment of a system disclosed herein;

[0040] FIG. 4B shows yet another embodiment of a system disclosed herein;

[0041] FIG. 5 shows schematically a use case of the systems of FIG. 4A or 4B;

[0042] FIG. 6A shows schematically a method of use of the systems in FIG. 4A or 4B;

[0043] FIG. 6B shows schematically another method of use of the systems in FIG. 4A or 4B;

[0044] FIG. 6C shows schematically yet another method of use of the systems in FIG. 4A or 4B;

[0045] FIG. 7A shows yet another embodiment of a system disclosed herein;

[0046] FIG. 7B shows yet another embodiment of a system disclosed herein;

[0047] FIG. 8 shows a vehicle cabin section and use case of a system in FIGS. 7A and 7B;

[0048] FIG. 9A shows schematically a method of use of the systems in FIG. 7A;

[0049] FIG. 9B shows schematically another method of use of the systems in FIG. 7B;

[0050] FIG. 10A shows yet another embodiment of a system disclosed herein;

[0051] FIG. 10B shows the resolution of an image obtained with known digital zoom,

[0052] FIG. 10C shows the resolution of an image obtained with “optical” zoom using the system of FIG. 10A.

DETAILED DESCRIPTION

[0053] FIG. 1A shows an embodiment of a system disclosed herein and numbered 100. System 100 may be installed in, or attached to a vehicle 102. System 100 includes a Tele camera 104, a Wide camera 106 and a processing unit (“processor”) 108. The vehicle may be for example a car, a bus, a truck, a motorcycle, a coach or any type of know vehicle. Processing unit 108 may be a CPU, GPU, ASIC, FPGA, or any other processor capable of graphic analysis. When used in conjunction with a vehicle, a system like system 100 may also be referred to as “advanced driver assistant system” or ADAS.

[0054] The combination of Tele camera 104 and Wide camera 106 may be referred as “dual-camera” and is numbered 110. FIG. 1B shows an example of elements of a dual-camera 110 in a perspective view. Wide camera 106 comprises a Wide sensor 132 and a Wide lens 134 with a Wide lens optical axis 136. Wide sensor 132 is characterized by a Wide sensor active area size and a Wide sensor pixel size. Wide lens 134 is characterized by a Wide effective focal length (EFL) marked EFL.sub.W. Optionally, in an embodiment, Wide lens 134 may have a fixed (constant) EFL.sub.W. Optionally, the Wide lens may be fixed at a constant distance from Wide image sensor 132 (fixed focus). Optionally, Wide lens 134 may be coupled to a focusing mechanism (e.g. an autofocus (AF) mechanism) that can change the distance of Wide lens 134 from Wide image sensor 132, thereby providing a non-fixed (variable) focus). The combination of Wide sensor area and EFL.sub.W determines the Wide FOV (FOV.sub.W). According to some examples, FOV.sub.W may be 50-100 degrees in the horizontal vehicle-facing direction.

[0055] Tele camera 104 comprises a Tele sensor 122 and a Tele lens 124 with a Tele lens optical axis 138. Tele sensor 122 is characterized by a Tele sensor active area size and a Tele sensor pixel size. Tele lens 124 is characterized by a Tele EFL, marked EFT.sub.T. Optionally, in an embodiment, Tele lens 124 may have fixed (constant) EFL. In some embodiments, the Tele lens may be fixed at a constant distance from Tele image sensor 122 (fixed focus). Optionally, the Tele lens may be coupled to a focusing mechanism (e.g. an AF mechanism) that can change the distance of Tele lens 124 from Tele image sensor 122 (non-fixed focus). The combination of Tele sensor area and Tele lens EFL.sub.T determines the Tele FOV (FOV.sub.T). According to some examples, FOV.sub.T may be between 10-30 degrees in the horizontal vehicle-facing direction. Thus, FOV.sub.T is smaller (narrower) than FOV.sub.W.

[0056] Tele camera 104 further comprises an OPFE 126, e.g. a mirror or a prism. OPFE 126 has a reflection surface tilted by 45 degrees at a rest point from the Tele lens optical axis 138. Tele camera 104 further comprises an actuator (motor) 128. Actuator 128 may tilt the reflecting surface of OPFE 126 by up to ±α degrees from the rest point (where exemplary α may be up to 10, 20, 40 or 70 degrees). That is, actuator 128 may tilt or scan the OPFE and with it FOV.sub.T. Actuator 128 may be for example a stepper motor, or a voice coil motor (VCM) as described for example in co-owned patent application PCT/IB2017/057706.

[0057] In some examples, Wide camera 106 and Tele camera 104 face a vehicle front side and share at least some of their respective FOVs. Typically, FOV.sub.W is directed away from the vehicle toward the front direction (driving direction) and is substantially symmetrical vs. the two sides of the vehicle. In one operational mode, the Tele camera is operational to scan the Tele FOV (FOV.sub.T) inside the Wide FOV (FOV.sub.W) using actuator 128. In some examples, the scanning of FOV.sub.T is for bringing the Tele camera to view more closely a detected potential object-of-interest (OOI), detected previously from Wide and/or Tele images, see in more detail below.

[0058] FIG. 2 shows schematically a use case of the system 100 of FIG. 1A. A dual-camera 110 is installed in a front part of a vehicle 102. For example, a triangle 204 represents FOV.sub.W in a horizontal plane, i.e. as a horizontal FOV.sub.W or “HFVO.sub.W”. In FOV.sub.W, an “observation distance” 206 is defined as the maximal distance that allows system 100 using an image from the Wide camera to detect a potential OOI. “OOI” may be for example a hazard, another vehicle, a hole or obstruction on a road, a pedestrian, a road curve, a road sign, etc. An “identification distance” 208 is defined as the minimal distance that allows system 100 using an image from the Wide camera to identify all the required information for making a decision, as known in the art. According to one example, the OOI may be a road sign observable but not readable in the observation distance. According to an example, an OOI may be observed in the observation distance, but identification or distinction between it being a road sign or a pedestrian is made only within the identification distance. In other words, if an OOI is located before (closer to the Wide camera than) the observation distance 206 but further than the identification distance 208, then system 100 may use an image from the Wide camera to calculate that the OOI is located in FOV.sub.W, but not to fully calculate required measures-of-action or response needed (see next).

[0059] According to some examples, measures-of-action or responses of system 100 may include one or more or a combination of the following: changing vehicle 102 speed and/or course, operating an internal alarm to the vehicle driver, operating an external alarm, sending data information to, or calling Internet/cloud based service/police/road assistance services, etc. For example, a triangle 210 represents FOV.sub.T in a horizontal plane, i.e. as a horizontal FVO.sub.T (HFVO.sub.T). According to one example, HFOV.sub.W may be in the range of 70-180 degrees and HFOV.sub.T may be in the range of 15-45 degrees. According to another example, HFOV.sub.W may be in the range of 140-180 degrees and HFOV.sub.T may be in the range of 15-70 degrees. Thus, the output images of the Tele camera may have higher resolution than the output images of the Wide camera. For example, the output image of the Tele camera may have 3 to 20 times more resolution than the output image of the Wide camera, and consequently identification distance 212 of the Tele camera may be 3 to 20 times further away than identification distance 208 of the Tele camera.

[0060] In an example shown in (a) of FIG. 2, vehicle 102 approaches OOI 202. OOI 202 is located between observation distance 206 and identification distance 208. While OOI 202 is observable by the Wide camera, it may not identifiable (namely the Wide camera captures OOI 202 with too low a resolution to identify, classify or handle, relative to the required by system 100). As shown in FIG. 2(b), POV.sub.T is then scanned to face OOI 202 such that the Tele camera may capture OOI 202 with more detail (e.g. “identify” it).

[0061] FIG. 3 shows a detailed flow chart of a method of operation of system 100 as in the example of FIG. 2: [0062] Step 302: Exemplarily, the Wide camera (e.g. 106) acquires Wide images. In some alternative embodiments, images may also or optionally be acquired by the Tele camera. [0063] Step 304: Exemplarily, the Wide camera sends Wide images acquired in step 302 to a processing unit (e.g. 108) for analysis. In some alternative embodiments, Tele images acquired in step 302 may also or optionally be to sent to the processing unit for analysis. [0064] Step 306: The processing unit detects the existence of OOI 202 in front of vehicle 102, but requires more details to address or decide on a course of action. [0065] Step 308: The processing unit directs the Tele camera (e.g. 104) to have FOV.sub.T face OOI 202 (i.e. by scanning the Tele camera), thereby acquiring and receiving images of OOI 202 with higher quality and/or higher resolution. The processing unit may then have more information on the OOI in order to fully calculate required measures-of-action or response needed.
In some examples, the Tele camera may be a camera equipped with a motor to drive the entire camera. In some examples, the Tele camera may be a folded camera as described in co-owned patent application PCT/IB2016/057366, in which the OPFE is operational to change (i.e. scan) a Tele camera point of view (POV). In some examples, the Tele camera may scan in one dimension (1D) only (i.e. along a line). In some examples, the Tele camera may scan in two dimensions (2D), namely scan an area. In some examples, the motor for scanning may be a VCM, a shape memory alloy (SMA) motor, a piezoelectric motor, a stepper motor or a DC motor. In some examples, the Tele camera and/or the Wide camera may be integrated with optical image stabilization (OIS) to compensate on vehicle vibrations.

[0066] FIG. 4A shows an embodiment of a system numbered 400 installed in, or attached to a vehicle 402. Optionally, vehicle 402 may have a steering wheel 416. In some vehicles, handlebars (not shown) may replace a steering wheel, with the following description being relevant to both. In contrast with system 100, system 400 comprises only a Tele camera 404 (similar to Tele camera 102) and a processing unit 408 (similar to processing unit 108).

[0067] FIG. 4B shows an embodiment of another system numbered 400′, similar to system 100 i.e. comprising a Wide camera 406 in addition to Tele camera 404. The description below refers to systems 400 and 400′. The Tele camera faces the vehicle front side. As seen in FIG. 5, in system 400, Tele camera 404 is operational to change angle/direction of POV.sub.T as marked by an arrow 502, thereby achieving an “effective” FOV marked FOV.sub.E, which is larger than FOV.sub.T. According to one optional use case of system 400 (FIG. 6A), a processing unit constantly commands the Tele camera to continually change the POV direction or angle from left to right and vice-versa (602), and the Tele camera rotates according to the commands received (604). In a second optional use case of system 400 (FIG. 6B), the processing unit follows the steering wheel or handle bars: when the user turns the steering wheel/handle bar to the left (612), the Tele camera POV (POV.sub.T) moves to the left, and when the user turns the steering wheel/handle bar to the right, POV.sub.T moves to the right. According to a third optional use case of system 400 (FIG. 6C), the processing unit may use image recognition algorithm to identify road curves and change FOV.sub.T to follow the road.

[0068] FIG. 7A shows another shows an embodiment of another system numbered 700 (similar e.g. to system 400) that may be installed in, or attached to a vehicle 702. Vehicle 702 comprises a vehicle cabin 716.

[0069] FIG. 7B shows an embodiment of yet another system numbered 700′, similar to system 100 and including a Wide camera 706 (like camera 106) in addition to Tele camera 704. Wide camera 706 may also be installed in vehicle cabin 716 to face OOI 802.

[0070] FIG. 8 shows a vehicle cabin section and use case of a system in FIGS. 7A and 7B. Wide camera 706 is not shown. Tele camera 704 with FOV.sub.T faces the interior of vehicle cabin 716 and an OOI 802, for example a passenger. Tele camera 704 may be scanned to allow the effective FOV (FOV.sub.E) larger than FOV.sub.T.

[0071] FIG. 9A shows in a flow chart main steps of a method of use of system 700. Tele camera 704 is operational to change angle/direction and scan vehicle cabin 716. Processing unit 708 is operational to identify an OOI 802 (e.g. passenger body, face, eyes, etc.). Processing unit 708 is further operational to direct Tele camera 704 to face OOI 802. The data obtained by the Tele camera is used for identifying hazards (e.g. driver not looking at the road, driver falling asleep, passengers without seatbelts, a child without a child seat, etc.). FIG. 9B shows in a flow chart main steps of a method of use of system 700′. The processing unit uses data from both Wide and Tele cameras to direct the Tele camera to OOI 802.

[0072] FIG. 10A shows an embodiment of yet another system disclosed herein and numbered 1000. System 1000 comprises a Tele camera 1002, a Wide camera 1004 and a processing unit 1006 and may be used for surveillance, thus being also named “surveillance camera”. Tele camera 1002 and Wide camera 1004 are part of a dual-camera 1010. These components may be similar to or even identical with Wide and Tele cameras and processors described in embodiments above. Surveillance camera 1000 and processing unit 1006 may include software and algorithms to detect OOIs (for example human faces) in FOV.sub.W and to steer the Tele camera in X and Y directions in Wide images to these OOIs to enhance the image or video quality of these objects and to enable their analysis (e.g. for face recognition in the case where the object is a face).

[0073] In an embodiment, processing unit 1006 may instruct Tele camera 1002 to continuously scan parts of FOV.sub.W. In an embodiment, processing unit 1006 may instruct Tele camera 1002 to move to a specific location (as in FIG. 9). The tilting and settling time of the prism may occur in 5-50 msec. Further, Tele camera 1002 may switch from pointing from one region of interest (ROI) to another every 1 sec, or at a faster or slower pace. FIG. 10B shows an example of an imaged scene acquired by Wide camera 1004 and then digitally zoomed, and FIG. 10C shows an example of an imaged scene acquired by Wide camera 1004 (left side) and then by a directed Tele camera 1002 to optically zoom on the ROI (right side). The zoomed image in FIG. OC shows significant resolution gain over the digitally zoomed image in FIG. 10B, allowing for example facial recognition of people in the ROI.

[0074] Wide and Tele images and/or video streams may be recorded during automatic tracking mode and may be fused together to form a composite image or a composite video stream, as known in the art. This fusion may be applied on a camera hosting device (e.g. a mobile electronic device of any type that includes a system or camera disclosed herein). Alternatively, Wide and Tele images or video streams may be uploaded to the cloud for applying this fusion operation. Each composite image may also have the same FOV, by scanning with the Tele camera, stitching a plurality of Tele images to provide a “stitched” Tele image, then fusing the stitched Tele image with a Wide image. This is advantageous in that the Wide image captures the entire scene simultaneously, while the Tele images to be stitched together are consecutive, so one can overcome motion or occlusions in the scene if required. The stitching of the Tele images and/or the fusion of the stitched Tele image with the Wide image may also be performed in a cloud.

[0075] While this disclosure has been described in terms of certain embodiments and generally associated methods, alterations and permutations of the embodiments and methods will be apparent to those skilled in the art. The disclosure is to be understood as not limited by the specific embodiments described herein, but only by the scope of the appended claims.