Abstract
Folded cameras and dual folded-upright cameras that reduce a mobile electronic device and specifically a smartphone bump footprint and height. In some examples, the bump footprint is reduced by reducing the height of a back focal plane section of the folded camera. In some examples, the bump footprint is reduced by reducing the height of a back focal plane section and a lens subsection of the folded camera.
Claims
1. A folded camera, comprising: an optical path folding element (OPFE) section including an OPFE for folding an optical path from a first direction to a second direction, the OPFE section having an OPFE height H.sub.P in the first direction; and a lens section positioned between the OPFE and an image sensor, the lens section having at least one lens section height H.sub.L in the first direction, wherein H.sub.L<H.sub.P.
2. The folded camera of claim 1, further comprising a back focal length (BFL) section extending between the lens section and the image sensor and having a BFL section height H.sub.BFL in the first direction, and wherein H.sub.BFL≤H.sub.L.
3. The folded camera of claim 2, wherein the lens section includes two subsections, wherein a lens subsection closer to the BFL section has a height H.sub.L2, and wherein H.sub.L2<H.sub.L.
4. The folded camera of claim 3, wherein H.sub.L2=H.sub.BFL.
5. The folded camera of claim 2, further comprising a flash element positioned on the BFL section and having a height H.sub.FLASH<H.sub.P.
6. A dual-aperture camera comprising a folded camera according to claim 1 together with an upright camera.
7. The dual-aperture camera of claim 6, wherein the upright camera has an upright camera optical axis parallel to the first direction.
8. A mobile electronic device comprising a folded camera according to claim 1.
9. The mobile electronic device of claim 8, comprising a bump on a surface thereof, wherein the bump surrounds an area including the folded camera and wherein at least one bump dimension is defined by a folded camera dimension.
10. The mobile electronic device of claim 9, wherein the bump has a length, L.sub.B, defined along the second direction, wherein the dual-aperture camera has a length, L.sub.DC, defined along the second direction, and wherein L.sub.B<L.sub.DC.
11. The mobile electronic device of claim 9, wherein the mobile electronic device is a smartphone.
12. A mobile electronic device comprising a dual-aperture camera according to claim 6.
13. The mobile electronic device of claim 12, comprising a bump on a surface thereof, wherein the bump surrounds an area including the folded camera and wherein at least one bump dimension is defined by a folded camera dimension.
14. The mobile electronic device of claim 13, wherein the bump has a length, L.sub.B, defined along the second direction, wherein the dual-aperture camera has a length, L.sub.DC, defined along the second direction, and wherein L.sub.B<L.sub.DC.
15. The mobile electronic device of claim 13, wherein the mobile electronic device is a smartphone.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0046] 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 may be labeled with the same numeral in 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.
[0047] FIG. 1A shows a known folded camera in a perspective view;
[0048] FIG. 1B shows the folded camera of FIG. 1A in a longitudinal cross section view;
[0049] FIG. 1C shows the folded camera of FIG. 1A in a side view;
[0050] FIG. 2A shows a known dual upright-folded camera in a perspective view;
[0051] FIG. 2B shows the dual upright-folded camera of FIG. 2A in a longitudinal cross section view;
[0052] FIG. 2C shows the dual upright-folded camera of FIG. 2A in a side view;
[0053] FIG. 3A shows a known dual upright-upright camera included in a smartphone in a back view;
[0054] FIG. 3B shows a known upright-upright camera with flash included in a smartphone in a back view;
[0055] FIG. 4A shows a dual folded-upright camera of FIGS. 1A-1C included in a smartphone in a perspective view, according to an exemplary embodiment disclosed herein;
[0056] FIG. 4B shows a cross section with enlarged details of the dual-camera and the smartphone of FIG. 4A;
[0057] FIG. 5A shows a folded camera in a perspective view according to another exemplary embodiment disclosed herein;
[0058] FIG. 5B shows the folded camera of FIG. 5A in a longitudinal cross section view;
[0059] FIG. 5C shows the folded camera of FIG. 5A in a side view;
[0060] FIG. 6A shows a dual folded-upright camera in a perspective view according to another exemplary embodiment disclosed herein;
[0061] FIG. 6B shows the dual folded-upright camera of FIG. 6A in a longitudinal cross section view;
[0062] FIG. 6C shows the dual folded-upright camera of FIG. 6A in a side view;
[0063] FIG. 7A shows the dual folded-upright camera of FIGS. 6A-6C included in a smartphone in a perspective view, according to an exemplary embodiment disclosed herein;
[0064] FIG. 7B shows a cross section with enlarged details of the dual folded-upright camera and the smartphone of FIG. 7A;
[0065] FIG. 8A shows a folded camera image sensor mounted on a board of a folded camera as in FIGS. 4A, 4B;
[0066] FIG. 8B shows a known folded camera image sensor mounted a board of a folded camera as in FIGS. 6A, 6B;
[0067] FIG. 9A shows a folded camera in a perspective view according to another exemplary embodiment disclosed herein;
[0068] FIG. 9B shows the folded camera of FIG. 9A in a longitudinal cross section view;
[0069] FIG. 9C shows the folded camera of FIG. 9A in a side view;
[0070] FIG. 10A shows a dual folded-upright camera in a perspective view according to another exemplary embodiment disclosed herein;
[0071] FIG. 10B shows the dual folded-upright camera of FIG. 10A in a longitudinal cross section view;
[0072] FIG. 10C shows the dual folded-upright camera of FIG. 10A in a side view;
[0073] FIG. 11A shows the dual folded-upright camera of FIGS. 10A-10C included in a smartphone in a perspective view, according to an exemplary embodiment disclosed herein;
[0074] FIG. 11B shows a cross section with enlarged details of the dual folded-upright camera and the smartphone of FIG. 11A.
[0075] FIG. 12A shows a folded camera with a flash element in a perspective view according to an exemplary embodiment disclosed herein;
[0076] FIG. 12B shows the folded camera of FIG. 12A in a longitudinal cross section view;
[0077] FIG. 13A shows a dual folded-upright camera with a folded camera as in FIG. 12 in a perspective view according to an exemplary embodiment disclosed herein;
[0078] FIG. 13B shows a dual folded-upright camera with a folded camera as in FIG. 12 in a perspective view according to another exemplary embodiment disclosed herein;
[0079] FIG. 14A shows a folded camera as in FIG. 9 with a flash element in a perspective view according to an exemplary embodiment disclosed herein;
[0080] FIG. 14B shows a folded camera as in FIG. 9 with a flash element in a perspective view according to another exemplary embodiment disclosed herein;
[0081] FIG. 14C shows a folded camera as in FIG. 9 with a flash element in a perspective view according to yet another exemplary embodiment disclosed herein;
[0082] FIG. 15A shows a dual folded-upright camera with a folded camera as in FIG. 14 in a perspective view according to an exemplary embodiment disclosed herein;
[0083] FIG. 15B shows the dual folded-upright camera of FIG. 15A in a side view.
DETAILED DESCRIPTION
[0084] Folded cameras described herein comprise an optical path folding element (OPFE), a lens and an image sensor. Folded cameras may further include other parts required for operation, including a focusing mechanism, an optical image stabilization (OIS) mechanism, a zooming mechanism, a mechanical shield, an infra-red (IR) filter, electronics to operate focusing, a gyroscope, a shutter and/or other parts. Folded cameras may further include additional optical elements between the OPFE and the object to be photographed. The lens of folded cameras described herein may have constant focal length, or may have varying focal length (also known as “zoom lens”).
[0085] A folded camera height is generally smaller than the height of an upright camera with a similar effective focal length (EFL). The decrease in the folded cameras height results from the fact that the folded camera height is not dependent on the lens height, which is correlated with the lens focal length. In an upright camera, its height is dependent on the lens height. Therefore, the lens focal length may be increased without sacrifice in the camera module height. However, the folded camera height is determined by lens assembly height and the height of other parts of the camera, for example an actuator (e.g. an actuator used to shift the lens for focus and\or optical image stabilization) and a shield height, and cannot be reduced beyond a certain minimum value, without sacrificing optical performance. In general, the height of folded cameras according to presently disclosed subject matter may be in the range of 3-8 mm.
[0086] It is desirable that smartphones and other mobile electronic devices having cameras with one (or more) folded camera(s) and/or one (or more) upright camera(s) have a bump footprint (width and length) as small as possible. Independently, it would be desirable in such smartphones and/or mobile electronic devices to have a bump height as small as possible
[0087] FIG. 4A shows a smartphone 400 comprising a dual folded-upright camera similar to camera 200 in a perspective view, according to an exemplary embodiment disclosed herein. FIG. 4B shows enlarged details of the dual-camera and the smartphone in a cross-section A-A. A bump 404 generally surrounding the dual-camera section protrudes above a surface of smartphone 402. The bump has a length L.sub.B1, a width W.sub.B1, and a height H.sub.B1. In some examples L.sub.B1 has a range of 5-50 mm, W.sub.B1 has a range of 1-20 mm and H.sub.B1 has a range of 0.05-3 mm. While its edges are shown as sharp, they are preferably rounded as in the bump of FIG. 3. By positioning the folded and upright cameras in a line (along a single axis), one can obtain a smaller bump footprint than, for example, positioning the folded and upright cameras in an arrangement in which the two do not share the same single axis. Note that everywhere except in the region of the bump, the phone has a thickness (height) between external surfaces H.sub.Phone. In the region of the bump, the phone thickness is larger and marked H.sub.PB.
[0088] The present inventors have found that the dimensions of a bump that accommodates a dual folded-upright camera may further be reduced by judicious design of the folded camera.
[0089] FIGS. 5A-5C show, in various views, a folded camera structure numbered 500 according to an exemplary embodiment disclosed herein. Like camera 100, camera 500 includes an OPFE section 502 with length L.sub.P and width W.sub.P, a lens section 504 with length L.sub.L and width W.sub.L and a back focal length (BFL) section 506 with length L.sub.BFL and width W.sub.BFL. Camera 500 may have a height H.sub.FL, a length L.sub.FL and a width W.sub.FL similar to that of camera 100. L.sub.FL is defined by the sum of L.sub.P+L.sub.L+L.sub.BFL. L.sub.P could basically be defined by the reflecting element height (for example a prism). In some examples according to presently disclosed subject matter, H.sub.FL is in the range of 3-8 mm, L.sub.FL is in the range of 10-30 mm and W.sub.FL is in the range of 3-15 mm. Note that the width of different folded camera sections may be different from each other and from W.sub.FL. These camera height, length and width dimensions apply in following disclosed embodiments even if not shown in figures.
[0090] Camera 500 may include other components with respective functionalities similar to or identical with the components of camera 100. Therefore, these components and their respective functionalities are not described in detail. Further, camera 500 may include two BFL sections or a split BFL section. Unlike in camera 100, BFL section 506 in camera 500 has a height H.sub.BFL that is smaller than the height of the lens section H.sub.L and a height of the OPFE (for example a prism) section H.sub.P. For example, H.sub.BFL may be smaller than H.sub.L by 0.05-3 mm. The reduction in height is expressed at a “shoulder” 508. In some examples, H.sub.L and H.sub.P may be substantially equal (up to 5% difference). In other examples, H.sub.L may be smaller than H.sub.P. In some embodiments, camera 500 may have a lens section width W.sub.L which is larger than the lens section height H.sub.L. In some embodiments, W.sub.L may be equal to H.sub.L. In some embodiments, a lens accommodated in the lens section may have a shape with radial symmetry (for example a cylindrical shape). In some embodiments, a lens accommodated in the lens section may have shape which does not have radial symmetry (for example a rectangular shape, a cylinder with chamfers, etc.).
[0091] Camera 500 can be included together with an upright camera 204 in a dual-camera 600 as shown in FIGS. 6A-6C. In the case of dual-camera, each of the two cameras may be called a “sub camera”. In some examples, upright camera may have an optical axis 110′ which is parallel to the first direction 110. The distance between optical axis 110′ and first direction 110 is defined a baseline of folded dual-camera 600. In some examples, the length L.sub.DC and width W.sub.DC of dual-camera 600 remain similar to those of dual-camera 200. However, dual-camera 600 has a lower height H.sub.BFL in the BFL section 506 of the folded camera. Therefore, when dual-camera 600 is incorporated in a mobile device such as a smartphone 700, the lower height of the BFL section enables a shorter bump length.
[0092] FIG. 7A shows the dual folded-upright camera of FIGS. 6A-6C included in a smartphone 700 in a perspective view. FIG. 7B shows a cross section with enlarged details of the dual folded-upright camera and the smartphone. Smartphone 700 has a bump 604 protruding over a surface 602. Bump 604 has a length L.sub.B2 and a height H.sub.B2. L.sub.B2 is smaller than L.sub.DC by about the length of BFL section 506. In this example, the dual-camera components that protrude and are visible include only the top of the lens of the upright camera and top parts of the OPFE. In some examples, lens sections of the folded camera may also be visible. In general, a bump may be needed only in areas of the camera where a height of the upright camera and a height of a section of the folded camera is larger than H.sub.phone.
[0093] Returning now to FIGS. 5A-5C, the reduction of height in the BFL section causes second direction 112 of the folded camera to be closer to a top surface 510 than to a bottom surface 512 of BFL section 506, creating asymmetry in the propagation of light rays exiting the lens into the BFL section. One result of the asymmetry is that an image sensor 514, which is normally mounted on a board 516 is asymmetrically positioned in the Y direction relative to the top and bottom sides of the BFL section and of the board itself.
[0094] FIG. 8A shows a known art image sensor 514 and board 516 as viewed in a +Z direction (along second direction 112). Sensor 514 is, for example, a silicon die that has an optically active part 802 (referred hereafter as active part 802) surrounded by a part (auxiliary silicon logic) 804 considered “non-active” in terms of image\light sensing and referred to therefore as non-active part 804. Active part 802 may be located in non-active part 804 in any position symmetrically or asymmetrically, as known in the art. Active part 802 is distanced from the top and bottom of board 516 (i.e. in the Y direction shown) by distances marked as D.sub.TOP and D.sub.BOT respectively. In FIG. 8A, D.sub.TOP=D.sub.BOT±Δ, where Δ is typically 0 to 200 m. This is a sensor-board arrangement in a known folded camera such as camera 100, where active part 802 is typically positioned symmetrically or slightly asymmetrically relative to board 516 (“slightly” referring to up to 200 μm out of the height (4-6 mm) or about 0-5% of the PCB height).
[0095] FIG. 8B shows an image sensor 514 and board 516 configuration 800 according to an embodiment disclosed herein. In configuration 800, active part 802 is positioned asymmetrically relative to board 516 in the Y direction, and A may be on the order of 100-1500 m. In this case, the asymmetry of active part 802 relative to board 516 may be on the order of 100 μm and up to 1-1.5 mm, or about 5%-30% of the PCB height.
[0096] The asymmetry results in a surface closer to the sensor's effective ray envelope and may cause stray light effects on the sensor. For example, in camera 500, top surface 510 is lower and closer to the sensor than a top surface of lens section 504, allowing for light that is entering to bounce off of top surface 510 and be redirected back to the sensor. To mitigate such effects, an internal surface 518 of top surface 510 of BFL section 506 is structured to prevent stray light. This may be provided, for example, by a yoke with a special structure and/or with an anti-reflective coating. Alternatively, an internal surface 520 of bottom 512 of BFL section 506 or both top and bottom internal surfaces 518 and 520 are structured to prevent stray light. In certain embodiments, internal surface 518 is uneven and/or has various ridges, so that it is not flat. Alternatively, FIG. 9B illustrates a method for absorbing or redistributing the light in other directions.
[0097] FIGS. 9A-9C show, in various views, a folded camera structure numbered 900 according to another exemplary embodiment disclosed herein. Like camera 500, camera 900 includes an OPFE section 902, a lens section 904 and a back focal length (BFL) section 906. The dimensions of the folded camera and the different sections may be in the same range as in cameras 100 and 500. Camera 900 may include other components with respective functionalities similar to or identical with the components of camera 500. Therefore, these components and their respective functionalities are not described in detail. Further, camera 900 may include two BFL sections or a split BFL section. Unlike in camera 500, lens section 904 in camera 900 has two different sub-sections 904a and 904b with two different heights marked H.sub.L and H.sub.L1. Height H.sub.L of lens sub-section 904a is larger than height H.sub.L1 of sub-section 904b, to accommodate at least one lens element 920 with a larger diameter D than the diameters of following (in the direction of the image sensor) lens elements (which, for example, have a smaller diameter D.sub.1) For example, H.sub.L1 may be smaller than H.sub.L by 0-3 mm.
[0098] While the exemplary embodiment in FIGS. 9A-9C shows a lens section with two different heights associated with two different subsections, a lens section may have more than two subsections with different heights. For example, if a lens includes N lens elements (typically N being between 1 and 6), then the lens section may include between 1 and N sub-sections. The N subsections may have the same height or different heights H.sub.LN. In some embodiments with different lens subsection heights H.sub.LN, the height may decrease in a step-wise manner from a subsection close to the OPFE (prism) section to a subsection close to the BFL section.
[0099] Camera 900 can be included together with an upright camera 204 in a dual-camera 1000 as shown in FIGS. 10A-10C. In some examples, the length L.sub.DC and width W.sub.DC of dual-camera 1000 remains similar to those of dual-camera 600. However, dual-camera 1000 has a lower height not only in the BFL section 906 of the folded camera, but also in sub-section 904b of the lens section. Therefore, when dual-camera 1000 is incorporated in a mobile device such as a smartphone, the lower height of the BFL section H.sub.BFL and of sub-section 904b H.sub.L2 enables an even shorter bump length L.sub.B3.
[0100] FIG. 11A shows the dual folded-upright camera of FIGS. 10A-10C included in a smartphone 1002 in a perspective view. FIG. 11B shows a cross section with enlarged details of the dual folded-upright camera and the smartphone. Smartphone 1100 has a bump 1104 protruding over a surface 1102. Bump 1104 has a length L.sub.B3 and a height H.sub.B2. To clarify, in smartphone 1100, L.sub.B3 is smaller than L.sub.B2 in FIG. 7 by about the length of lens sub-section 904b and is smaller than L.sub.FL by about the length of BFL section 906 plus the length of lens sub-section 904b. The marking of the bump height with “H.sub.B2” here and in FIG. 7B does not necessarily mean that bumps 604 and 1104 have the same height. In this example, the dual-camera components that protrude and are visible include only the top of the lens of the upright camera and top parts of the OPFE and lens sub-section 904a of the folded camera. In general, a bump may be needed only in areas of the camera where a height of the upright camera and a height of a section of the folded camera is larger than H.sub.phone.
[0101] Camera 500 can be provided with a flash (e.g. LED) element to obtain a folded camera with flash (or “flash folded camera”). FIG. 12A shows a perspective view, and FIG. 12B shows a side view of a flash folded camera 1200. A flash element 1204 may provide an external illumination source as needed by the photographed scene, as known in the art. The reduction of height in camera 500 BFL (H.sub.BFL) may be used to house flash element 1204, i.e. flash element 1204 may be placed on top of top surface 510. The combined height from the bottom of camera 500 to the top of flash element 1204 is marked by H.sub.FLASH, as seen in FIG. 12B. In some cases, H.sub.FLASH may be smaller than, or equal to camera 500 height (H.sub.FL), as seen in FIG. 12B.
[0102] Folded camera 1200 may be included with an upright camera 204 to form a dual camera. FIGS. 13A-13B show two embodiments of such a dual-camera. In FIG. 13A, a dual-camera 1302 includes an upright camera 204 positioned next to flash folded camera 1200 on the optical axis (+Z direction) toward the side of OPFE section 502. In FIG. 13B, a dual-camera 1304 includes an upright camera 204 positioned along camera 1200 on the optical axis closer to BFL section 506 side. In dual camera 1304, flash element 1204 is positioned between the optical aperture of camera 204 and the optical aperture of camera 500.
[0103] In other dual-camera embodiments, shown in FIGS. 14A-14C, a camera such as camera 900 may also be provided with a flash element such as flash element 1204, which may be positioned on top of BFL section 906 (FIG. 14A), on top of lens sub-section 904 (FIG. 14B), or on top of both of these sections (FIG. 14C) (partially on top of each section in some embodiments). In all these cases, H.sub.FLASH will mark the combined height of from bottom of camera 900 to top of flash element 1204. H.sub.FLASH may be smaller than or equal to camera height H.sub.FL. That is, the addition of a flash element does not lead to any protrusion above the largest height of the folded camera. Cameras 1400, 1402 or 1404 may be combined with an upright camera to form a dual camera (not shown).
[0104] In yet another dual-camera embodiment numbered 1500 and shown in FIGS. 15A and 15B, camera 900 may be combined with an upright camera 204 and flash element 1204, such that the flash element is positioned partially above camera 900 and partially above camera 204.
[0105] 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.
