Optical system for long-focus camera

Abstract

An optical system for a camera can include a lens group having a plurality of lenses, a prism, and an image sensor. The prism can be optically positioned between the plurality of lenses and the image sensor along an optical transmission path of light. The prism can include at least four surfaces that can fold the light within the prism at least four times to direct the light from the plurality of lenses through the prism to the image sensor. The prism can include a plurality of prisms joined together using an optical adhesive. The prism can include one or more aperture masks located inside the prism to reduce glare.

Description

background Technical Field

[0002] This disclosure relates generally to cameras, and more specifically to optical systems for small form factor cameras. Background Technology

[0004] Telephoto cameras typically have relatively long focal lengths and are well-suited for capturing scenes and subjects at a distance. However, the emergence of small, mobile multi-purpose devices such as smartphones, tablets, tablets, or wearable devices has created a demand for integrating high-resolution, small-form-factor cameras into these devices. Therefore, there is a need for optical systems suitable for small-form-factor, high-quality telephoto cameras. Attached Figure Description

[0005] Figure 1 An exemplary optical system according to some implementation schemes is shown.

[0006] Figure 2A Exemplary values ​​for some parameters of an optical system according to some implementation schemes are shown.

[0007] Figure 2B Exemplary values ​​for some additional parameters of an optical system according to some embodiments are shown.

[0008] Figures 3A to 3C An exemplary prism including an eyelet mask is shown according to some embodiments.

[0009] Figures 4A to 4H Exemplary design variations of an optical system according to some implementation schemes are shown.

[0010] Figure 5 Exemplary values ​​for some parameters of some exemplary optical systems according to some implementation schemes are shown.

[0011] Figures 6A to 6H Exemplary values ​​for some additional parameters for some exemplary optical systems according to some implementation schemes are shown.

[0012] Figure 7 A high-level flowchart of a method for capturing images using a camera including an optical system, according to some embodiments, is shown.

[0013] Figure 8 A high-level flowchart of an exemplary method for forming an optical system according to some implementation schemes is shown.

[0014] Figure 9 A schematic diagram of an exemplary device, which may include a camera with an optical system, is shown according to some embodiments.

[0015] Figure 10A schematic block diagram of an exemplary computer system, which may include a camera with an optical system, is shown according to some embodiments.

[0016] This specification includes references to "one embodiment" or "implementation". The use of the phrase "in one embodiment" or "in an embodiment" does not necessarily refer to the same embodiment. Specific features, structures, or characteristics may be combined in any suitable manner consistent with this disclosure.

[0017] The term "comprising" is open-ended. As used in the appended claims, it does not exclude additional structures or steps. Consider the following cited claim: "An apparatus comprising one or more processor units..." Such claims do not exclude the inclusion of additional components (e.g., network interface units, graphics circuitry, etc.).

[0018] "Configured as" refers to various units, circuits, or other components that can be described or stated as being "configured as" to perform one or more tasks. In such a context, "configured as" is used to imply a structure (e.g., a circuit) that includes a unit / circuit / component that performs one or more tasks during operation. Thus, a unit / circuit / component is allegedly configured to perform the task even when the specified unit / circuit / component is currently inoperable (e.g., not switched on). Units / circuits / components used with the language "configured as" include hardware—e.g., circuits, memory storing program instructions that can be executed to perform the operation, etc. Referring to a unit / circuit / component as being "configured as" to perform one or more tasks is explicitly intended to exclude reference to 35 U.S.SC §112(f) for that unit / circuit / component. Furthermore, "configured as" can include general structures (e.g., general-purpose circuits) manipulated by software and / or firmware (e.g., FPGAs or general-purpose processors executing software) in a manner capable of performing one or more tasks to be solved. "Configured to" may also include adjusting the manufacturing process (e.g., a semiconductor manufacturing facility) to manufacture equipment (e.g., an integrated circuit) suitable for performing one or more tasks.

[0019] "First," "second," etc. As used herein, these terms serve as labels for the nouns preceding them and do not imply any type of ordering (e.g., spatial, temporal, logical, etc.). For example, a buffer circuit may be described herein as performing write operations on a "first" value and a "second" value. The terms "first" and "second" do not necessarily imply that the first value must be written before the second value.

[0020] "Based on." As used herein, this term describes one or more factors that influence the determination. This term does not exclude additional factors influencing the determination. That is, the determination may be based solely on these factors or at least partially on them. Consider the phrase "A is determined based on B." In this case, B is the factor influencing the determination of A, and such phrases do not exclude the possibility that the determination of A may also be based on C. In other instances, A may be determined solely on B.

[0021] It will also be understood that while the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. For example, without departing from the intended scope, a first contact may be referred to as a second contact, and similarly, a second contact may be referred to as a first contact. Both the first contact and the second contact are contacts, but they are not the same contact.

[0022] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used in the specification and appended claims, the singular forms “a,” “an,” and “the” are intended to also cover the plural forms unless the context otherwise expressly indicates otherwise. It will also be understood that the term “and / or” as used herein refers to and covers any and all possible combinations of one or more of the items listed in connection with the description. It will also be understood that the terms “comprising” and / or “including” as used in this specification specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0023] As used herein, depending on the context, the term "if" can be interpreted as meaning "when..." or "in response to determination" or "in response to detection". Similarly, depending on the context, the phrase "if it is determined..." or "if [the stated condition or event] is detected" can be interpreted as meaning "when it is determined..." or "in response to determination..." or "when [the stated condition or event] is detected" or "in response to detection". Detailed Implementation

[0024] The various embodiments described herein relate to optical systems for cameras (specifically, small-form-factor telephoto cameras). In some embodiments, such telephoto cameras can be integrated into small, mobile, multi-functional devices (e.g., smartphones, tablets, tablet computers, wearable devices, etc.). In some embodiments, the optical system may include multiple lenses, prisms, and an image sensor. In some embodiments, the prism may be optically arranged between the multiple lenses and the image sensor along an optical transmission path of light captured by the multiple lenses to the image sensor. In some embodiments, the prism may have at least four surfaces. For example, the prism may include a parallelogram prism, with a first surface parallel to a third surface and a second surface parallel to a fourth surface. In some embodiments, the prism may be arranged such that the first surface is positioned facing the multiple lenses, while the third surface is positioned facing the image sensor. In some embodiments, the second and fourth surfaces of the prism may each include a reflective coating (or reflector) such that the second and fourth surfaces can reflect light at their respective surfaces, and the first and third surfaces of the prism can reflect light at their respective surfaces when the angle of incidence of light is close to or greater than a critical angle.

[0025] In some embodiments, the prism can fold light within the prism, thereby guiding light from the plurality of lenses through the prism to the image sensor. For example, for a parallelogram prism, light from the plurality of lenses can enter the prism through a first surface. At least some of the light can reach a second surface of the prism and then be reflected there, for example, the light is folded once. At least some of the light reflected from the second surface of the prism can be reflected back to the first surface of the prism. Total internal reflection (TIR) ​​can occur when the angle of incidence of the light is close to or greater than the critical angle of the prism, so the light can be reflected at the first surface of the prism, for example, the light is folded twice. At least some of the light reflected from the first surface can be transmitted to a third surface of the prism and reflected there, for example, the light is folded three times. Next, at least some of the light reflected from the third surface of the prism can reach a fourth surface of the prism and be reflected there, and then leave the prism to reach the image sensor, for example, the light is folded four times. In short, in the example of the parallelogram prism described above, light can be folded four times within the prism before reaching the image sensor. Given that a prism can have multiple surfaces, for example, at least four, it can be designed to have a thin thickness; for example, the length between the first and third surfaces of the parallelogram prism can have a small value, yet it can still fold light multiple times. Such a prism can reduce at least the Z-height (e.g., the height along the optical axis or Z-axis of the lens), and thus reduce the overall size of the optical system.

[0026] Figure 1 An exemplary optical system according to some embodiments is shown. In this example, optical system 100 may include lens group 105, prism 110, and image sensor 115. Figure 1 A global optical coordinate system defined by the Y-axis, Z-axis, and angle α is also shown, where angle α refers to the angle relative to the Z-axis in a plane perpendicular to the Y-axis. In some embodiments, lens group 105 may include multiple lenses. In some embodiments, lens group 105 may include at least three lenses, such as lens 105(1)L1, lens 105(2)L2, and lens 105(3)L3, as... Figure 1 As shown. The plurality of lenses (e.g., lens 105(1)L1, lens 105(2)L2, and lens 105(3)L3) may individually include at least a front surface facing the environment and a rear surface opposite to the front surface, for example, as... Figure 1 The lenses 105(1)L1, L1S1 and L1S2, 105(2)L2, L2S1 and L2S2, and 105(3)L3, L3S1 and L3S2 are indicated in the diagram. In some embodiments, the optical system 100 may include an aperture stop 120 that may limit and control the amount of light entering or captured by the lens group 105. In some embodiments, the optical system 100 may optionally include an infrared filter (IF) 125, such as... Figure 1 As shown, this IF can block or prevent at least some infrared light from reaching the image sensor 115. For example... Figure 1 As shown, the infrared filter (IF) may include at least a first surface (IFS1) facing the prism 110 and a second surface (IFS2) facing the image sensor 115.

[0027] In some implementation schemes, such as Figure 1 As shown, the optical system 100 may include a prism 110 optically arranged between the lens group 105 and the image sensor 115 along the optical transmission path of light from the lens group 105 to the image sensor 115. In some embodiments, the prism 110 may include at least four surfaces. For example, as Figure 1As shown, prism 110 may include a parallelogram prism, with a first surface (prism S1) of prism 110 parallel to a third surface (prism S3) of prism 110, and a second surface (prism S2) of prism 110 parallel to a fourth surface (prism S4) of prism 110. In some embodiments, prism 110 may be arranged such that the first surface (prism S1) faces the lens group 105, and the third surface (prism S3) faces the image sensor 115. In some embodiments, the front surface of the first lens of the lens group 105 (e.g., surface L1S1 of lens 105(1)L1) may be substantially parallel to the image plane of the image sensor 115, such that light incident on the front surface of the first lens 105(1)L1 may be parallel to light incident on the image plane of the image sensor 115.

[0028] In some embodiments, the second surface (prism S2) and / or the fourth surface (prism S4) of prism 110 may individually include a reflective coating (or reflector). For example, the reflective coating may include a mirror coating based on a thin metal layer, a film having a white inner surface, etc. Therefore, the second surface (prism S2) and the fourth surface (prism S4) of prism 110 may reflect light at their respective surfaces. The first surface (prism S1) and the third surface (prism S3) of prism 110 may transmit light or allow light to pass through their respective surfaces. Furthermore, the first surface (prism S1) and the third surface (prism S3) of prism 110 may reflect light under a phenomenon known as total internal reflection (TIR). TIR occurs when the angle of incidence of light approaches or exceeds a certain limiting angle (called the critical angle). The angle of incidence is the angle between light incident on a surface and a line perpendicular to the surface at the point of incidence (called the normal). Therefore, when the angle of incidence of light is less than the critical angle, the first surface (prism S1) and the third surface (prism S3) of prism 110 allow light to pass through. Conversely, when the angle of incidence of light is close to or greater than the critical angle, the first surface (prism S1) and the third surface (prism S3) of prism 110 reflect light at the corresponding surfaces. In some embodiments, the first surface (prism S1) and / or the third surface (prism S3) of prism 110 may also individually include an anti-reflective coating.

[0029] Re-reference Figure 1 Prism 110 can fold light within prism 110 multiple times to guide light from lens group 105 through prism 110 to image sensor 115. For example, for Figure 1 The parallelogram prism 110 shown allows light from lens group 105 to pass through its first surface (prism S1) and enter. At least some of the light reaches the second surface (prism S2) of prism 110 and is then reflected there, such as... Figure 1The edges of the prism indicate, for example, that the light is folded once. At least some of the light reflected from the second surface (prism S2) of prism 110 can bounce back to the first surface (prism S1) of prism 110, as shown in the image. Figure 1 The edges are indicated in the image sensor 110. When the angle of incidence of light is close to or greater than the critical angle of prism 110, the light can be reflected at the first surface (prism S1) of prism 110 under TIR, for example, the light is folded twice. Next, at least some of the light reflected from the first surface (prism S1) can be transmitted to the third surface (prism S3) of prism 110 and reflected at the third surface, for example, the light is folded three times. Finally, at least some of the light reflected from the third surface (prism S3) of prism 110 can reach the fourth surface (prism S4) of prism 110, be reflected at the fourth surface (prism S4), and leave prism 110 to be focused on the image plane on the image sensor 115, for example, the light is folded four times. Therefore, in Figure 1 In this example, at least some of the light passing through the lens group 105 may be folded four times within the prism 110 before leaving the prism 110 and reaching the image sensor 115.

[0030] The aforementioned light folding of prism 110 can effectively increase the focal length between lens group 105 and image sensor 115 of optical system 100. For example, in some embodiments, the ratio between the optical path length of light entering prism 110 through the first surface (prism S1) and exiting prism 110 through the third surface (prism S3) and the focal length of lens group 105 can be in the range of 0.6 and 1.0, for example, 0.6 < (optical path length in prism 110 × optical power of lens group 105) < 1.0, where optical power is the reciprocal of the focal length of lens group 105. Therefore, optical system 100 can use a thin prism 110 (e.g., with a small thickness approximately between the first surface (prism S1) and the third surface (prism S3) of prism 110) to still provide a long and effective focal length for telephoto cameras. For example, in some embodiments, such as Figure 1As shown, the ratio between a portion of the Z-height of the optical system 100 (e.g., measured approximately along the optical axis or Z-axis between the first surface (prism S1) and the image plane of the image sensor 115) and the total Z-height (e.g., measured approximately along the optical axis or Z-axis between the front surface of the first lens (L1S1) of the lens group 105 and the image plane of the image sensor 115) can be in the range of 0.2 to 0.6, for example, 0.2 < (partial Z-height / total Z-height) < 0.6, and the ratio between the thickness of the prism 110 (e.g., measured approximately from the first surface (prism S1) to the third surface (prism S3) of the prism 110) and the thickness of the lens group 105 (e.g., measured approximately from the front surface (L1S1) of the first lens and the rear surface (L3S2) of the last lens of the lens group 105) can be in the range of 0.2 to 0.8, for example, 0.2 < (thickness of prism 110 / thickness of lens group 105) < 0.8. If the Z-height ratio and / or thickness ratio is too high, the prism 110 may be too large and heavy and may not be able to effectively reduce the size of the optical system 100, or the lens group 105 may be too thin and may not be able to achieve good light-catching performance. Alternatively, if the Z-height ratio and / or thickness ratio is too low, the prism 110 may be too thin and may not be able to capture enough light from the entire field of view (FOV). Therefore, the optical system 100 is designed with appropriate parameters to reduce at least a portion of the Z-height and / or the total Z-height of the optical system 100, while still maintaining high-quality optical performance. In some embodiments, the reduction in Z-height can correspondingly reduce the size of the optical system 100, and thus is beneficial for the design and integration of small-form-factor telephoto cameras (using the optical system 100). In some embodiments, a portion of the Z-height of the optical system 100 may be in the range of 3.57 mm to 5.6 mm. In some embodiments, the thickness of the prism 110 of the optical system 100 may be in the range of 2.07 mm to 4.1 mm. In some embodiments, the effective focal length of the optical system 100 is in the range of 17.2 mm to 27.2 mm. In some embodiments, the aperture number of the optical system 100 is in the range of 2.2 to 2.8. Figure 1 More exemplary values ​​for some parameters of the optical system 100 can be found in Figure 2A middle.

[0031] It should be noted that, for illustrative purposes, prism 110 is... Figure 1 The prism 110 is shown as a parallelogram prism. In some embodiments, prism 110 may include other shapes, such as pentagons, hexagons, etc., and still provide the aforementioned light folding functionality and design benefits. For a given shape, the angles between the various surfaces of prism 110 can also be designed for desired performance. For example, in some embodiments, when prism 110 comprises a parallelogram prism, such as... Figure 1As shown, the angle θ between the first surface (prism S1) and the second surface (prism S2) of prism 110 can be in the range of 25 degrees and 35 degrees (e.g., 25 degrees < θ < 35 degrees). In some embodiments, the plurality of lenses of lens group 105 (e.g., lens 105(1)L1, lens 105(2)L2, and lens 105(3)L3) can be made of various light-transmitting materials. For example, lens group 105 may include a combination of both glass lenses and plastic lenses. In another example, all lenses of lens group 105 may be either glass lenses or plastic lenses. Similarly, prism 110 may also include various light-transmitting materials, such as one or more glass prisms, one or more plastic prisms, or a combination of both glass prisms and plastic prisms. Compared to glass, plastic offers less weight and lower material costs. In some embodiments, using a glass lens for the first lens of the lens group (e.g., 105(1)L1 of lens group 105) can mitigate thermal focusing shift within the optical system (e.g., optical system 100). For example, thermal focusing shift can be suppressed to less than 0.25 μm / degree. In some embodiments, axial chromatic aberration can be corrected by using a material with a high dispersion coefficient Vd (e.g., Vd > 60) for the first lens of the lens group (e.g., 105(1)L1 of lens group 105). In some embodiments, lens group 105 may include one or more rotationally symmetric lenses. A rotationally symmetric lens may refer to a lens that has symmetrical optical properties relative to the optical axis or Z-axis of the lens. In other words, rotation of the lens about the Z-axis will not affect the optical properties of the lens. In some embodiments, all lenses of lens group 105 may be aspherical lenses. In some embodiments, all lenses of lens group 105 may be spherical lenses. In some embodiments, lens group 105 may include a combination of both aspherical and spherical lenses. A spherical lens may refer to a lens that has the same curve having a similar spherical shape across at least one surface, while an aspherical lens may refer to a lens having a surface whose curvature gradually changes from the center of the lens outward to the edge. In some embodiments, aspherical lenses may help optical system 100 achieve a low aperture number. For a given focal length, a lower aperture number means that the optical system 100 can use a larger aperture stop 120, thus allowing the camera including the optical system 100 to have a fast shutter speed. In some embodiments, the aspherical surface of the lens may be designed according to the following formula:

[0032]

[0033] Where z refers to the sag of the aspherical surface parallel to the optical axis of the lens, h is the radial distance from the optical axis, r is the radius of curvature, k is the conic constant, and A, B and C refer to the 4th, 6th and 8th order aspherical coefficients, respectively. Figure 2B It shows Figure 1Exemplary values ​​for some additional parameters of the optical system 100 shown.

[0034] Figures 3A to 3C An exemplary prism including an eyelet mask is shown according to some embodiments. In some embodiments, an eyelet mask is provided to reduce or mitigate glare. For optical systems, glare can be caused when stray light from the environment (especially stray light brighter than the light from the scene or subject the camera is capturing) enters the optical system. Stray light from the environment can enter the optical system from various directions of the camera and / or other components (e.g., the sidewalls of the camera housing) and ultimately enter the image. Figure 3A As shown, stray light 310 may enter prism 305, for example, from the surface of prism 305 (e.g., prism S4). In some embodiments, the prism may include one or more eyelet masks located inside the prism and / or on the prism surface to reduce glare. In this example, prism 315 may include eyelet masks 325 and 330 located inside prism 315, such as Figure 3B As shown. Furthermore, in some embodiments, the aperture mask 325 and / or 330 may be designed to have various shapes and / or sizes in various spatial locations. The aim is for the aperture mask 325 and / or 330 to cover an area assumed to be illuminated by stray light from the environment. In this way, the aperture mask 325 and / or 330 can intercept and absorb stray light, thereby reducing glare, such as... Figure 3B As shown. For example, as Figure 3B As shown, aperture masks 325 and 330 can be positioned parallel to each other on opposite sides inside prism 315 to mitigate glare caused by stray light from opposite sides of prism 315 (e.g., surface prisms S2 and S4). In some embodiments, aperture masks 325 and 330 can have the same or different shapes. As shown in this example, aperture mask 325 can have a different shape than aperture mask 330, such that aperture mask 325 blocks stray light at the bottom and sides, while aperture mask 330 prevents stray light at the top and sides. Note that, for illustrative purposes, Figures 3A to 3B Provided for illustrative purposes only. When glare is caused by stray light from one or more other directions, the size, shape, and / or position of the aperture mask can be modified accordingly to achieve the desired anti-glare performance. In some embodiments, aperture masks 325 and / or 330 may individually include an anti-glare coating, a dark (e.g., black) mask, a dark (e.g., black) paint, a change in flange shape, etc.

[0035] In some implementations, the prism (e.g., Figure 1The prism 110 in the diagram may comprise a single, one-piece prism. In some embodiments, the prism can be formed by bonding several prisms together, for example, with an optically transparent adhesive. According to some embodiments, the latter method can be used to form an eyelet mask inside the prism. For example, as... Figure 3C As shown, prism 315 can be formed by bonding prisms 340, 345, and 350. In this example, prism 315 can be parallelogram-shaped, and therefore can be formed using a rectangular prism 340 and two triangular prisms 345 and 350. In some embodiments, to form eyelet masks 325 and / or 330 inside prism 315, eyelet masks 325 and / or 330 can first be formed at corresponding surfaces of the rectangular prism 340. For example, eyelet masks 325 and 330 can be formed on two opposing parallel surfaces of the rectangular prism 340, such as... Figure 3C As shown. Next, the rectangular prism 340 (with eyelet masks 325 and 330) can be bonded to the triangular prisms 345 and 350, such that the eyelet masks 325 and 330 can be positioned at the corresponding mating surfaces between the rectangular prism 340 and the triangular prisms 345 / 350.

[0036] Figures 4A to 4H Exemplary design variations of an optical system according to some implementation schemes are shown. For example... Figures 4A to 4H As shown, in some embodiments, the lens group of the optical system may include a variety of numbers of lenses. For example, Figure 4A The lens group 405a of the optical system 400a may include four lenses, while Figure 4D The lens group 405d of the optical system 400d may have three lenses. Furthermore, in some embodiments, the optical system may include lenses of various shapes and sizes, for example, by comparison... Figure 4A and Figure 4F These design variations also Figures 4B to 4C , Figure 4E and Figures 4G to 4H As shown in the diagram. Furthermore, in some embodiments, the optical system may include lenses and / or prisms of various materials (e.g., glass, plastic, etc.). Such design variations are found in... Figure 5 and Figures 6A to 6H This is further illustrated below. For example, Figure 5 and Figures 6A to 6H Examples of values ​​for some parameters are shown, such as Figures 4A to 4H The optical systems in the examples are 400a to 400h. It should be noted that, for illustrative purposes, Figure 1 Figures 6 to 6 illustrate the use of prisms (e.g., prisms 110, 315, and 410a to 410h) to achieve light folding in optical systems (e.g., optical systems 100 and 400a to 400h). In some embodiments, the optical system may not require prisms and may use any suitable light folding element.

[0037] Figure 7 A high-level flowchart of an exemplary method for capturing images using a camera including an optical system, according to some embodiments, is shown. Figure 7 As shown, in some embodiments, the optical system (e.g., Figure 1 Multiple lenses (e.g., in the optical system 100) Figure 1 Multiple lenses (L1 to L3) can receive light from a scene or subject in the environment, as indicated by box 705. As described above, in some embodiments, the multiple lenses may include at least three lenses having various materials, shapes, and / or sizes. In some embodiments, the optical system may include a prism (e.g., Figure 1 Prism 110 in the optical system, which can be optically arranged among the plurality of lenses and image sensor (e.g., Figure 1 Between the image sensor 115 in the image sensor. In some embodiments, the prism may include at least four surfaces (e.g., Figure 1 (The four surfaces of the parallelogram prism in the image sensor) can fold light within the prism at least four times to guide light from the multiple lenses through the prism to the image sensor.

[0038] As described above, in some embodiments, some surfaces of the prism (e.g., surface prism S2 and surface prism S4) may individually include a reflective coating (or reflector). Therefore, in some embodiments, light captured by the plurality of lenses can pass through the first surface of the prism (e.g., Figure 1The light enters the prism via a surface prism S1, as indicated by box 710. In some embodiments, at least some of the light passing through the first surface can reach a second surface of the prism (e.g., surface prism S2) and can be reflected at the second surface, as indicated by box 715. In some embodiments, at least some of the light reflected from the second surface can bounce back to the first surface. As described above, TIR can occur when the angle of incidence of light is close to or greater than the critical angle of the prism, and the light can be further reflected at the first surface of the prism, as indicated by box 720. In some embodiments, at least some of the light reflected from the first surface of the prism can be transmitted to a third surface of the prism (e.g., surface prism S3) and reflected at the third surface, as indicated by box 725. Similarly, when the angle of incidence of light is close to or greater than the critical angle, the light can be reflected at the third surface of the prism, as indicated by box 725. In some embodiments, at least some of the light reflected from the third surface may reach a fourth surface of the prism (e.g., surface prism S4) and be reflected at that fourth surface to leave the prism and reach an image sensor, as indicated by block 730. In some embodiments, the image sensor may detect the light and generate an image signal (e.g., an electrical signal) accordingly, based on which an image may be generated, as indicated by block 735.

[0039] Figure 8 A high-level flowchart of an exemplary method for forming an optical system according to some embodiments is shown. For illustrative purposes, Figure 8 Using a parallelogram prism as an example, the disclosed method can also be applied to prisms of other shapes and / or sizes. Figure 8 As shown, the method may include obtaining a rectangular prism (e.g., Figures 3B to 3C The rectangular prism 340 is shown in box 805. In some embodiments, one or more eyelet masks (e.g., eyelet masks 325 and / or 330) may be formed at the rectangular prism to reduce glare, as indicated in box 810. For example, the eyelet masks may be formed on two opposing parallel surfaces of the rectangular prism (e.g., Figures 3B to 3C (As shown). In some embodiments, the rectangular prism can be joined with one or more other prisms using an optical adhesive (e.g., two prisms (e.g., prisms 345 and 350)) to form a parallelogram prism (e.g., parallelogram prism 315), as indicated by box 815. In some embodiments, an eyelet mask can be positioned at the joint surface between the prism and the corresponding prism (e.g., ...). Figures 3B to 3C (As shown).

[0040] In some implementations, the parallelogram prism can be used with a lens group comprising multiple lenses (e.g., Figure 1The lens group 105 is assembled together, as indicated by box 820. For example, a parallelogram prism and the lens group can be assembled such that the first surface of the parallelogram prism (e.g., surface prism S1) can face the rear surface of the last lens in the lens group (e.g., surface L3S2 of lens 105(3)L3) (e.g.) Figure 1 (As shown). Therefore, the light captured by the lens group can pass through the lenses of the lens group (e.g., from lens 105(1)L1, through lens 105(2)L2, and to lens 105(3)L3), and then enter the prism through the first surface of the prism. In some embodiments, the lens group and the parallelogram prism can be assembled with an image sensor (e.g., image sensor 115) to form an optical system (e.g., optical system 100), as indicated by block 825. For example, the lens group and the parallelogram prism can be assembled with an image sensor such that the third surface of the parallelogram prism (e.g., surface prism S1) opposite (and parallel to) the first surface of the prism can face the image sensor (e.g., as shown). Figure 1 (As shown). Therefore, light from the lens group can enter the prism through the first surface, fold multiple times (e.g., at least four times) inside the prism, and pass through the third surface of the prism to reach the image sensor, as described above. In some embodiments, an infrared filter (e.g., infrared filter 125) may optionally be included between the prism and the image sensor in the optical system to block or prevent at least some infrared light from reaching the image sensor.

[0041] Figure 9 A schematic diagram of an exemplary device 900 according to some embodiments is shown. This exemplary device may include having an optical system (e.g., Figure 1 The optical system 100 and Figures 4A to 4H The camera (optical system 400a to 400h) is included. In some embodiments, device 900 may be a mobile device and / or a multi-functional device. In various embodiments, device 900 may be any of a variety of types of devices, including but not limited to: personal computer systems, desktop computers, laptops, notebook computers, tablet computers, all-in-one computers, tablet computers or netbooks, mainframe computers, handheld computers, workstations, network computers, cameras, set-top boxes, mobile devices, augmented reality (AR) and / or virtual reality (VR) headsets, consumer devices, video game controllers, handheld video game devices, application servers, storage devices, televisions, video recording equipment, peripherals (such as switches, modems, routers), or any type of computing or electronic device in general.

[0042] In some embodiments, device 900 may include display system 902 (e.g., including a display and / or a touch-sensitive surface) and / or one or more cameras 904. In some non-limiting embodiments, display system 902 and / or one or more forward-facing cameras 904a may be disposed on the front side of device 900, for example, as shown in the image. Figure 9 As indicated. Additionally or alternatively, one or more rear-facing cameras 904b may be located at the rear of the device 900. In some embodiments including multiple cameras 904, some or all of the cameras may be identical or similar to each other. Additionally or alternatively, some or all of the cameras may be different from each other. In various embodiments, the position and / or arrangement of the cameras 904 may vary. Figure 9 The cameras indicated in the document.

[0043] Among other things, device 900 may include memory 906 (e.g., including operating system 908 and / or application / program instructions 910), one or more processors and / or controllers 912 (e.g., including CPU, memory controller, display controller, and / or camera controller, etc.) and / or one or more sensors 916 (e.g., orientation sensor, proximity sensor, and / or position sensor, etc.). In some embodiments, device 900 may communicate with one or more other devices and / or services, such as computing device 918, cloud service 920, etc., via one or more networks 922. For example, device 900 may include a network interface (e.g., network interface 910) that enables device 900 to transmit data to and receive data from network 922. Additionally or alternatively, device 900 may be able to communicate wirelessly with other devices using any of a variety of communication standards, protocols, and / or technologies.

[0044] Figure 10 A schematic block diagram of an exemplary computing device, referred to as computer system 1000, is shown, which may include or host an implementation of a camera having an optical system, such as those referenced herein. Figures 1 to 9 As described above. Furthermore, the computer system 1000 can implement methods for controlling the operation of the camera and / or for performing image processing on images captured by the camera. In some embodiments, additionally or alternatively, the device 900 (referencing herein) Figure 9 The components described herein may include some or all of the functional components of the computer system 1000 described herein.

[0045] Computer system 1000 may be configured to perform any or all of the embodiments described above. In different embodiments, computer system 1000 may be any of a variety of types of devices, including but not limited to: personal computer systems, desktop computers, laptops, notebook computers, tablet computers, all-in-one computers, tablet computers or netbooks, mainframe computers, handheld computers, workstations, network computers, cameras, set-top boxes, mobile devices, augmented reality (AR) and / or virtual reality (VR) headsets, consumer devices, video game controllers, handheld video game devices, application servers, storage devices, televisions, video recording equipment, peripheral devices (such as switches, modems, routers), or any type of computing or electronic device in general.

[0046] In the illustrated embodiment, computer system 1000 includes one or more processors 1002 coupled to system memory 1004 via input / output (I / O) interface 1006. Computer system 1000 also includes one or more cameras 1008 coupled to I / O interface 1006. Computer system 1000 also includes a network interface 1010 coupled to I / O interface 1006 and one or more input / output devices 1012, such as cursor control device 1014, keyboard 1016, and display 1018. In some cases, it is conceivable that an embodiment may be implemented using a single instance of computer system 1000, while in other embodiments, multiple such systems or multiple nodes constituting computer system 1000 may be configured to host different parts or instances of the embodiment. For example, in one embodiment, some elements may be implemented via one or more nodes of computer system 1000 that are different from those nodes implementing other elements.

[0047] In various embodiments, computer system 1000 may be a single-processor system including one processor 1002, or a multiprocessor system including several processors 1002 (e.g., two, four, eight, or another suitable number). Processor 1002 may be any suitable processor capable of executing instructions. For example, in various embodiments, processor 1002 may be a general-purpose or embedded processor implementing any of a variety of instruction set architectures (ISAs) (such as x86, PowerPC, SPARC, or MIPS ISA or any other suitable ISA). In a multiprocessor system, each processor in processor 1002 may, but is not required to, implement the same ISA.

[0048] System memory 1004 may be configured to store program instructions 1020 accessible by processor 1002. In various embodiments, system memory 1004 may be implemented using any suitable memory technology, such as static random access memory (SRAM), synchronous dynamic RAM (SDRAM), non-volatile / flash memory, or any other type of memory. Furthermore, existing camera control data 1022 in memory 1004 may include any of the aforementioned information or data structures. In some embodiments, program instructions 1020 and / or data 1022 may be received, transmitted, or stored on a different type of computer-accessible medium or similar medium separate from system memory 1004 or computer system 1000. In various embodiments, some or all of the functions described herein may be implemented via such computer system 1000.

[0049] In one embodiment, I / O interface 1006 may be configured to coordinate I / O communication between processor 1002, system memory 1004, and any peripheral devices (including network interface 1010 or other peripheral device interfaces, such as input / output device 1012) within the device. In some embodiments, I / O interface 1006 may perform any necessary protocol, timing, or other data conversions to convert data signals from one component (e.g., system memory 1004) into a format suitable for use by another component (e.g., processor 1002). In some embodiments, I / O interface 1006 may include support for devices attached, for example, via various types of peripheral bus (e.g., variants of the Peripheral Component Interconnect (PCI) bus standard or the Universal Serial Bus (USB) standard). In some embodiments, the functionality of I / O interface 1006 may be divided among two or more separate components, such as a north bridge and a south bridge. Furthermore, in some embodiments, some or all of the functionality of I / O interface 1006 (such as an interface to system memory 1004) may be directly incorporated into processor 1002.

[0050] Network interface 1010 can be configured to allow data exchange between computer system 1000 and other devices (e.g., bearers or agent devices) attached to network 1024, or between nodes of computer system 1000. In various embodiments, network 1024 may include one or more networks, including but not limited to local area networks (LANs) (e.g., Ethernet or enterprise networks), wide area networks (WANs) (e.g., the Internet), wireless data networks, some other electronic data network, or some combination thereof. In various embodiments, network interface 1010 may support communication, for example, via wired or wireless general-purpose data networks (such as any suitable type of Ethernet network); via telecommunications / telephone networks (such as analog voice networks or digital fiber optic communication networks); via storage area networks (such as Fibre Channel SANs); or via any other suitable type of network and / or protocol.

[0051] In some implementations, input / output device 1012 may include one or more display terminals, keyboards, keypads, touchpads, scanning devices, voice or optical recognition devices, or any other device suitable for inputting or accessing data by one or more computer systems 1000. Multiple input / output devices 1012 may be present in the computer system 1000 or distributed across various nodes of the computer system 1000. In some implementations, similar input / output devices may be separate from the computer system 1000 and may interact with one or more nodes of the computer system 1000 via wired or wireless connections (such as through network interface 1010).

[0052] Those skilled in the art will understand that the computer system 1000 is merely illustrative and not intended to limit the scope of the embodiments. Specifically, the computer system and device may include any combination of hardware or software capable of performing the indicated functions, including computers, network devices, internet devices, personal digital assistants (PDAs), wireless telephones, pagers, etc. The computer system 1000 may also be connected to other devices not shown, or conversely, may operate as a stand-alone system. Furthermore, the functions provided by the illustrated components may, in some embodiments, be combined into fewer components or distributed across additional components. Similarly, in some embodiments, the functionality of some of the illustrated components may not be provided, and / or other additional functions may be available.

[0053] Those skilled in the art will also recognize that, although various items are shown as being stored in memory or on storage devices during use, these items, or portions thereof, may be transferred between memory and other storage devices for memory management and data integrity purposes. Alternatively, in other embodiments, some or all of these software components may be executed in memory on another device and communicate with the illustrated computer system via inter-computer communication. Some or all of the system components or data structures may also be stored (e.g., as instructions or structured data) on a computer-accessible medium or portable article of manufacture for reading by a suitable drive, various examples of which are described above. In some embodiments, instructions stored on a computer-accessible medium separate from computer system 1000 may be transmitted to computer system 1000 via a transmission medium or signal (such as electrical, electromagnetic, or digital signals transmitted via communication media such as networks and / or wireless links). Various embodiments may also include receiving, transmitting, or storing instructions and / or data implemented according to the above description on a computer-accessible medium. Generally, computer-accessible media may include non-transitory computer-readable storage media or memory media, such as magnetic or optical media, like discs or DVD / CD-ROMs, and volatile or non-volatile media, such as RAM (e.g., SDRAM, DDR, RDRAM, SRAM, etc.), ROM, etc. In some embodiments, computer-accessible media may include transmission media or signals, such as electrical signals, electromagnetic signals, or digital signals transmitted via communication media such as networks and / or wireless links.

[0054] In various implementations, the methods described herein can be implemented in software, hardware, or a combination thereof. Furthermore, the order of the blocks of the method can be changed, and various elements can be added, reordered, combined, omitted, modified, etc. Various modifications and changes will be apparent to those skilled in the art who benefit from this disclosure. The various implementations described herein are intended to be illustrative and not restrictive. Many variations, modifications, additions, and improvements are possible. Thus, multiple examples may be provided for a component described herein as a single example. The boundaries between various components, operations, and data repositories are somewhat arbitrary, and specific operations are shown in the context of a particular exemplary configuration. Other allocations of functionality are contemplated, which may fall within the scope of the appended claims. Finally, the structures and functions of discrete components presented in exemplary configurations can be implemented as combined structures or components. These and other variations, modifications, additions, and improvements may fall within the scope of the implementations as defined in the following claims.

Claims

1. A camera, the camera comprising: Multiple lenses; Image sensor; and A prism, wherein the prism is configured as follows: Light passing through the plurality of lenses is transmitted through the first surface to the prism; At least some of the light that has passed through the first surface of the prism is reflected at the second surface of the prism; At least some of the light reflected from the second surface of the prism is reflected at the first surface of the prism; At least some of the light reflected from the first surface of the prism is reflected at the third surface of the prism; as well as At least some of the light reflected from the third surface of the prism is reflected at the fourth surface of the prism so that it passes through the third surface, leaves the prism, and reaches the image sensor. The angle between the first and second surfaces of the prism is in the range of 25 degrees and 35 degrees; and The Z-height of the portion of the camera between the first surface of the prism and the image plane of the image sensor is in the range of 3.57 mm and 5.6 mm.

2. The camera of claim 1, wherein at least one of the second surface or the fourth surface of the prism comprises a reflective coating.

3. The camera of claim 1, wherein at least one of the first surface or the third surface of the prism comprises an anti-reflective coating.

4. The camera of claim 1, wherein the plurality of lenses comprises at least one of a glass lens or a plastic lens.

5. The camera according to claim 1, wherein each of the plurality of lenses is a spherical lens.

6. The camera of claim 1, wherein the ratio B / A is in the range of 0.2 and 0.6, wherein B represents a portion of the Z-height of the camera between the first surface of the prism and the image plane of the image sensor, and A represents the total Z-height of the camera between the front surface of the first lens of the plurality of lenses and the image plane of the image sensor.

7. The camera of claim 1, wherein the product CD is in the range of 0.6 and 1.0, wherein C represents the optical path length of light in the prism from the entry of the light into the prism to the exit of the prism, and D represents the optical power of the plurality of lenses.

8. The camera of claim 1, wherein the effective focusing path of the camera is in the range of 17.2 mm and 27.2 mm.

9. The camera of claim 1, wherein the ratio E / F is in the range of 0.2 and 0.8, wherein E represents the thickness of the prism between the first and third surfaces of the prism, and F represents the thickness of the plurality of lenses between the front surface of the first lens and the rear surface of the last lens of the plurality of lenses.

10. The camera of claim 1, wherein the prism comprises a parallelogram prism, and wherein the first surface of the prism is parallel to the third surface of the prism, and the second surface of the prism is parallel to the fourth surface of the prism.

11. The camera of claim 1, wherein the prism comprises a plurality of prisms joined together using an optical adhesive.

12. The camera of claim 1, wherein the prism includes one or more eyelet masks configured to reduce glare located inside the prism.

13. The camera of claim 12, wherein the one or more eyelet masks are positioned at corresponding mating surfaces between the rectangular prism and the two triangular prisms.

14. An electronic device comprising: One or more cameras; and One or more processors, the one or more processors being configured to process image signals generated from the one or more cameras, At least one of the one or more cameras includes: Multiple lenses; Image sensors; and A prism, wherein the prism is configured as follows: Light passing through the plurality of lenses is transmitted through the first surface to the prism; At least some of the light that has passed through the first surface of the prism is reflected at the second surface of the prism; At least some of the light reflected from the second surface of the prism is reflected at the first surface of the prism; At least some of the light reflected from the first surface of the prism is reflected at the third surface of the prism; and At least some of the light reflected from the third surface of the prism is reflected at the fourth surface of the prism so that it passes through the third surface, leaves the prism, and reaches the image sensor. The angle between the first and second surfaces of the prism is in the range of 25 degrees and 35 degrees; and The Z-height of the portion of the at least one camera between the first surface of the prism and the image plane of the image sensor is in the range of 3.57 mm and 5.6 mm.

15. The electronic device of claim 14, wherein at least one of the second surface or the fourth surface of the prism comprises a reflective coating.

16. The electronic device of claim 14, wherein the aperture number of the at least one camera is in the range of 2.2 and 2.8, and wherein the effective focal length of the at least one camera is in the range of 17.2 mm and 27.2 mm.

17. The electronic device of claim 14, wherein the prism comprises a parallelogram prism, wherein the first surface of the prism is parallel to the third surface of the prism, and the second surface of the prism is parallel to the fourth surface of the prism.

18. An optical system, the optical system comprising: Multiple lenses; and A prism having at least four surfaces, wherein the prism is configured as follows: Light passing through the plurality of lenses is transmitted through the first surface to the prism; At least some of the light that has passed through the first surface of the prism is reflected at the second surface of the prism; At least some of the light reflected from the second surface of the prism is reflected at the first surface of the prism; At least some of the light reflected from the first surface of the prism is reflected at the third surface of the prism; as well as At least some of the light reflected from the third surface of the prism is reflected at the fourth surface of the prism so that it passes through the third surface, leaves the prism, and reaches the image plane. The angle between the first and second surfaces of the prism is in the range of 25 degrees and 35 degrees; and This includes the portion of the camera in the optical system whose Z-height is between 3.57 mm and 5.6 mm, located between the first surface of the prism and the image plane of the camera's image sensor.

Images