Variable aperture device for camera modules and products including the same

Abstract

The present invention relates to a variable aperture device 10 for a camera module 1a. The device 10 includes a base 100 having a base opening 110, a pair of blade guides 120a, 120b, a pair of main blades 200a, 200b guided by the blade guides 120a, 120b, a pair of secondary blades 300a, 300b guided by the blade guides 120a, 120b, a cover 400 fixed to the base 100 and having a cover opening 410, and an actuator 500 for moving the main blades 200a, 200b and secondary blades 300a, 300b relative to the base 100. Each of the main blades 200a, 200b has a recess 210a, 210b, respectively. The recesses (210a, 210b) cooperate to define a central opening (A1) and a fixed opening (A2). Each auxiliary blade (300a, 300b) has a recess (310a, 310b), respectively. The recesses (310a, 310b) cooperate to define a minimum opening (A3) and a maximum opening (A4). Each auxiliary blade (300a, 300b) is configured to protrude outward from a side edge (230a, 230b) of the main blade (200a, 200b) perpendicular to the longitudinal edge (130a, 130b) of the base (100) when the pair of main blades (200a, 200b) are closest to each other.

Description

Technical Field

[0001] The present invention relates to a variable aperture device used in camera modules and camera units in various products, and particularly to various portable electronic devices including smartphones and mobile phones. The present invention also relates to products including such variable aperture devices.

Background Art

[0002] In recent years, in camera modules mounted on portable devices such as smartphones, variable aperture devices have attracted attention in order to achieve higher image quality. In addition to this, some smartphones have started to adopt a "macro shooting function".

[0003] In macro shooting, the variable aperture device contributes to obtaining higher optical performance and a larger depth of field.

[0004] Regarding the specifications of cameras, the demand for a larger aperture (smaller F value) is increasing, and accordingly, a larger aperture is also required for variable apertures.

[0005] However, a large-aperture variable aperture causes the variable aperture device itself to become larger, leading to an increase in the size of the camera module.

[0006] As a structure of a variable aperture device suitable for the requirement of miniaturization, for example, a structure in which two blades are driven by one actuator, as disclosed in Japanese Patent Application Laid-Open No. 2017-167186, has been proposed. In this structure, the variable aperture is realized by controlling the opening and closing of two blades. Also, in this structure, the arm is mechanically connected to the drive unit, and the two blades can be driven simultaneously by the movement (particularly, rotation) of the arm. Therefore, the space for the actuator for opening and closing the two blades can be reduced, and the size (particularly, its width) of the variable aperture device can be reduced.

[0007] On the other hand, Japanese Patent Publication No. 2021-056448 proposes a structure using a shape memory alloy element (hereinafter referred to as "SMA element") as an actuator to drive the blades. Generally, SMA elements are known as small actuators. In Japanese Patent Publication No. 2021-056448, because the size of the actuator is sufficiently small, the SMA elements are arranged overlapping in the thickness direction of the blades. Therefore, the variable aperture device can be miniaturized.

[0008] Generally, a variable aperture device has a fixed aperture that determines the amount of light passing through the device when it is in the "open state." When the variable aperture device is in the "closed state," a central aperture is formed by driving the blades to obtain a predetermined amount of light. In this state, optically, the central aperture should be positioned at the center of the fixed aperture.

[0009] In the structure shown in Japanese Patent Publication No. 2017-167186, the blade back size must be sufficiently large so that no holes other than the central hole are exposed when the blade is closed. Therefore, it is necessary to increase the space for housing the blade when it is open, which in turn leads to an increase in the size of the variable aperture device.

[0010] On the other hand, in the structure shown in Japanese Patent Publication No. 2021-056448, a small SMA element is used as the actuator, as described above. However, due to the characteristics of the SMA element, it is difficult to obtain a large stroke. This means that the movable stroke of the blades is greatly limited. For this reason, it is difficult to apply the SMA element to large-diameter variable aperture devices that require a long blade stroke. In addition, the solution described in Japanese Patent Publication No. 2021-056448, like the solution described in Japanese Patent Publication No. 2017-167186, cannot solve the problem of increasing the size of the variable aperture device due to the size of the rear part of the blades.

[0011] In summary, the problem with the structure disclosed in Japanese Patent Publication No. 2017-167186 is that it requires a sufficiently large size for the rear of the blades, which leads to an undesirable increase in the size of the variable aperture device. The problem with the structure disclosed in Japanese Patent Publication No. 2021-056448 is that it requires a sufficiently large size for the rear of the blades, which not only leads to an undesirable increase in the size of the variable aperture device, but also significantly restricts the blade stroke.

[0012] For these reasons, there is a need for a variable aperture device for camera modules that is smaller than conventional devices, yet offers a higher level of reliability than larger conventional devices. [Overview of the Initiative]

[0013] In view of the above, an object of the present invention is to provide a novel variable aperture device for a camera module that can overcome or at least mitigate the problems described above in relation to prior art devices. In particular, a more specific object of the present invention is to provide a novel variable aperture device for a camera module that is smaller than a prior art device and has a higher reliability level than a larger prior art device. [Means for solving the problem]

[0014] To achieve these objectives, the present invention provides a variable aperture device for a camera module, comprising: (i) a base having a base opening and a pair of blade guides, the pair of blade guides being provided on the opposing longitudinal edges of the base having the base opening in between; (ii) a pair of main blades guided by the pair of blade guides of the base, the pair of main blades being slidably arranged relative to the base so as to approach and separate from each other, each of the main blades having a notch, the notches cooperating to define a central opening when the pair of main blades are closest to each other and cooperating to define a fixed opening when the pair of main blades are furthest apart from each other; and (iii) a pair of blade guides of the base A variable aperture device is provided, comprising: (iv) a cover fixed to a base and having a cover opening substantially matching the fixed opening, the cover being configured to restrain a pair of main blades and a pair of auxiliary blades in the space between the base and the cover; and (v) actuators for moving the pair of main blades and a pair of auxiliary blades relative to the base. The variable aperture device according to the present invention is characterized in that, when the pair of main blades are closest to each other and the pair of auxiliary blades are closest to each other, each of the auxiliary blades is configured to protrude outward from the side edge of the main blade perpendicular to the longitudinal edge of the base.

[0015] The present invention also provides a product including a camera module, the camera module comprising a variable aperture device as described above.

[0016] According to the present invention, a pair of auxiliary blades are further added to the variable aperture device. These auxiliary blades are configured to protrude outward from the side edges (i.e., vertical edges) of the main blades when the pair of main blades are closest to each other and the pair of auxiliary blades are closest to each other. Thus, the problem that arises when the size of the main blades is shortened in its sliding direction (i.e., longitudinal or horizontal), namely the creation of an undesirable hole that allows light to pass through around the central opening of the variable aperture device, can be avoided. This is because the auxiliary blades can cover such an undesirable hole when they are in a protruding state. In other words, according to the present invention, by shortening the longitudinal (horizontal) length of the rear of the main blades, the variable aperture device can be made smaller, particularly in the longitudinal or horizontal direction, compared to any conventional device, without creating an undesirable hole. This is because shortening the longitudinal length of the rear of the main blades effectively saves space in the device for housing the main blades when they are open.

[0017] According to one preferred embodiment of the present invention, a pair of auxiliary blades are interposed between the base and a pair of main blades. However, in another embodiment of the present invention, a pair of auxiliary blades may be interposed between the cover and a pair of main blades.

[0018] According to one preferred embodiment of the present invention, the actuator includes a pair of rotatable arms with bosses at their tips, a pair of main blades each having a cam groove, a pair of auxiliary blades each having a cam groove, the bosses of the rotatable arms are configured to be housed within the cam grooves of the main blades and the auxiliary blades, and the rotation of the rotatable arms is converted into linear motion of the main blades and auxiliary blades by the cam grooves of the main blades and the auxiliary blades. In this preferred embodiment of the present invention, the pair of rotatable arms may be rotatably supported by a base. This embodiment provides a particularly simple and reliable structure. In another preferred embodiment of the present invention, the cover may have a pair of cam grooves, and the bosses of the rotatable arms may be configured to enter into the cam grooves of the cover.

[0019] According to a preferred embodiment of the present invention, when a pair of auxiliary blades moves to a closed position in which the smallest opening is jointly defined by the recesses of the pair of auxiliary blades, the cam grooves of the auxiliary blades are covered by the pair of main blades, and the cam grooves of the main blades are covered by the pair of auxiliary blades.

[0020] In one preferred embodiment of the present invention, when a pair of auxiliary vanes moves to a closed position in which the recesses of the pair of auxiliary vanes cooperate to define a minimum opening, a pair of rotatable arms is positioned substantially parallel to the direction of movement of the pair of auxiliary vanes. In this preferred embodiment of the present invention, when the pair of rotatable arms is positioned substantially parallel to the direction of movement of the pair of auxiliary vanes, the pair of rotatable arms can be hidden behind the pair of auxiliary vanes. This embodiment enables a particularly small structure of the device.

[0021] According to a preferred embodiment of the present invention, when a pair of main blades and a pair of auxiliary blades move linearly, the first arm and the second arm of a pair of rotatable arms rotate in opposite directions to each other. This also contributes to miniaturization of the device.

[0022] According to a preferred embodiment of the present invention, the variable aperture device further comprises a pair of secondary auxiliary vanes guided by a pair of vane guides on a base, the pair of secondary auxiliary vanes slidably arranged relative to the base to move toward and apart from each other, each of the secondary auxiliary vanes having a recess, the recesses cooperating to define a minimum opening surrounding a central opening when the pair of secondary auxiliary vanes are closest to each other, and cooperating to define a maximum opening surrounding or substantially coinciding with a fixed opening when the pair of secondary auxiliary vanes are furthest apart from each other, and each of the pair of secondary auxiliary vanes is configured to project outward from the lateral edge (vertical edge) of the main vanes perpendicular to the longitudinal edge of the base when the pair of main vanes are closest to each other, the pair of auxiliary vanes are closest to each other, and the pair of secondary auxiliary vanes are closest to each other. According to this embodiment, the area of ​​the portion of the main vane opposite to the side on which the recess is formed (i.e., the "rear of the vane") can be reduced. This will contribute to further miniaturization of devices.

[0023] According to a preferred embodiment of the present invention, each of the pair of secondary auxiliary vanes has its own cam groove, and the boss of the rotatable arm is configured to be further accommodated within the cam groove of the secondary auxiliary vane. The rotation of the arm is converted into a linear motion of the secondary auxiliary vane by the cam groove of the secondary auxiliary vane. Also by this embodiment, a particularly small structure is realized.

[0024] According to a preferred embodiment of the present invention, the pair of secondary auxiliary vanes are interposed between the base and the pair of auxiliary vanes. However, in other embodiments of the present invention, the pair of secondary auxiliary vanes may be interposed between the cover and the pair of main vanes, or between the pair of main vanes and the pair of auxiliary vanes.

[0025] According to a preferred embodiment of the present invention, the central opening defined in cooperation by the recesses of the main vanes is circular. Further, in a preferred embodiment of the present invention, the base opening, the fixed opening defined in cooperation by the recesses of the main vanes, the minimum and maximum openings defined in cooperation by the recesses of the auxiliary vanes, and the cover opening may be non-circular, for example, they may be substantially elliptical. However, these openings may be set to any shape and dimensions as necessary, as long as they do not interfere with the central opening.

[0026] A product provided with a camera module according to a preferred embodiment of the present invention may be a device, apparatus, instrument, machine, equipment, tool, etc. provided with the camera module. In particular, the product may be a portable electronic device including the camera module.

[0027] Hereinafter, non-limiting and representative embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Brief Description of the Drawings

[0028] [Figure 1] It is a schematic diagram of a product incorporating a camera module including a variable aperture device according to an embodiment of the present invention, that is, a smartphone. [Figure 2]This is a perspective view of the variable aperture device of the camera module shown in Figure 1, in the open state. [Figure 3] This is a front view of the variable aperture device shown in Figure 2, in the open state. [Figure 4] This is a front view of the variable aperture device shown in Figure 2, in the closed state. [Figure 5] Figures 2 to 4 show exploded perspective views of the variable aperture device. [Figure 6] This diagram schematically shows the fixed and central apertures formed in a conventional variable aperture device; the device cover has been removed for clarity. [Figure 7] Figures 2 to 5 schematically show the fixed and central apertures formed in the variable aperture device, with the device cover removed for clarity. [Figure 8] This diagram schematically shows the relationship between the arm stroke and blade stroke in a conventional variable aperture device; the device cover has been removed for clarity. [Figure 9] Figures 2 to 5 schematically show the relationship between the arm stroke and blade stroke in the variable aperture device; the device cover has been removed for clarity. [Figure 10] These figures schematically show the variable aperture device in its open and closed states, as viewed from the rear side (i.e., the lens side of the camera module). [Figure 11] These figures schematically show the positional relationship of each blade of the variable aperture device shown in Figures 2 to 5 when it is in the closed state, as viewed from the front. [Figure 12] This diagram schematically shows the positional relationship of each blade in the closed state in a comparative example where the shape of the cam groove is inappropriate, as viewed from the front. [Figure 13] This is an exploded perspective view of a variable aperture device according to another embodiment of the present invention. [Figure 14] Figure 13 is a plan view showing the modified shape of the main blades of the variable aperture device. [Figure 15]Figure 13 is a front view of a reference example illustrating the effects of the variable aperture device shown. [Modes for carrying out the invention]

[0029] Hereinafter, several exemplary embodiments of the present invention will be described with reference to Figures 1 to 15.

[0030] The terms used in this book, such as "front," "back," "side," "up," "down," "top," "bottom," "upward," "downward," "right," "left," "longitudinal," "lateral," "horizontal," and "vertical," are understood in relation to the orientation of the device shown in the diagrams, and may or may not correspond to the actual orientation during use.

[0031] The following exemplary embodiments of the present invention relate to a variable aperture device used in a camera module of a portable electronic device, in particular, but not limited to, a product such as a smartphone. Furthermore, the following exemplary embodiments of the present invention relate to such a product, in particular a portable electronic device having a camera module including a variable aperture device, which is one exemplary embodiment of the present invention. However, such a product may be any device, any apparatus, any equipment, any machine, any facility, any tool, etc., including a camera module.

[0032] Figure 1 shows a portable electronic device 1, i.e., a smartphone, according to a preferred embodiment of the present invention. The portable electronic device 1 incorporates a camera module 1a. The camera module 1a includes a variable aperture device (hereinafter also referred to as a "VA device") 10, which will be described in detail below.

[0033] Figure 2 is a perspective view showing the VA device 10 built into the camera module 1a shown in Figure 1. Figure 3 is a front view showing the same VA device 10. In Figures 2 and 3, the VA device 10 is in the "open state". That is, in the state shown in Figures 2 and 3, the VA device 10 has a fixed opening A2 (details will be described later).

[0034] Figure 4 is also a front view showing the VA device 10. However, unlike Figures 2 and 3, the VA device 10 is in a "closed state" in Figure 4. That is, in the state shown in Figure 4, the VA device 10 has a central opening A1 (details will be described later).

[0035] Figure 5 is an exploded perspective view showing the VA device 10. As can be seen from Figure 5, the VA device 10 mainly comprises a base 100, a pair of main blades 200a and 200b, a pair of auxiliary blades 300a and 300b, a cover 400, and an actuator 500. The base 100 and the cover 400 cooperate to form a rectangular casing C for housing the pair of main blades 200a and 200b, the pair of auxiliary blades 300a and 300b, and the rotatable arm of the actuator 500 (details to be described later). The body of the actuator 500 (i.e., the drive unit) is not shown, but this can be embodied by, for example, a micromotor, particularly an ultrasonic micromotor or an electromagnetic micromotor.

[0036] The base 100 has a base opening 110 and a pair of blade guides (i.e., a pair of guide rails) 120a, 120b. The base opening 110 substantially matches the fixed opening A2 in terms of shape and size. The pair of blade guides 120a, 120b are provided on the opposing longitudinal (horizontal) edges 130a, 130b of the base 100, flanking the base opening 110. The pair of blade guides 120a, 120b extend parallel to each other.

[0037] A pair of main blades 200a and 200b are guided by a pair of blade guides 120a and 120b on the base 100. That is, the pair of main blades 200a and 200b are slidably positioned relative to the base 100 so as to move closer to and further apart from each other. Also, the pair of main blades 200a and 200b always partially overlap. As can be seen in Figure 5, each of the main blades 200a and 200b has a roughly U-shape overall. More specifically, each of the main blades 200a and 200b comprises a rear blade portion (i.e., a base portion) 240a and 240b, and a pair of fingers 250a1, 250a2, 250b1, and 250b2 extending from both ends of the respective rear blade portions 240a and 240b. As a result, each of the main blades 200a and 200b has recesses 210a and 210b, respectively. The recesses 210a and 210b include a broad area involved in forming a fixed opening A2 and a semicircular area involved in forming a central opening A1, which extends further from the broad area to the rear portions 240a and 240b of each blade. Therefore, these two recesses 210a and 210b cooperate to define the central opening A1 when the pair of main blades 200a and 200b are closest to each other. In this embodiment, the central opening A1 defined by the cooperation of the recesses 210a and 210b is circular. Furthermore, the recesses 210a and 210b cooperate to define a fixed opening A2 when the pair of main blades 200a and 200b are furthest apart from each other.

[0038] A pair of auxiliary blades 300a and 300b are also guided by a pair of blade guides 120a and 120b on the base 100. That is, the pair of auxiliary blades 300a and 300b are slidably positioned relative to the base 100 so as to move closer to and further apart from each other. Also, the pair of auxiliary blades 300a and 300b always partially overlap. As can be seen from Figure 5, each of the auxiliary blades 300a and 300b as a whole is roughly U-shaped. More specifically, each of the auxiliary blades 300a and 300b comprises a rear blade portion (i.e., base portion) 340a and 340b, and a pair of fingers 350a1, 350a2, 350b1, and 350b2 extending from both ends of each rear blade portion 340a and 340b. As a result, each of the auxiliary vanes 300a and 300b has recesses 310a and 310b, respectively. These two recesses 310a and 310b work together to define a minimum opening A3 (see Figures 7 and 10) surrounding the central opening A1 when the pair of auxiliary vanes 300a and 300b are closest to each other. Furthermore, the recesses 310a and 310b work together to define a maximum opening A4 (see Figure 7) when the pair of auxiliary vanes 300a and 300b are furthest apart from each other. The maximum opening A4 substantially coincides with the fixed opening A2.

[0039] The cover 400 is secured to the base 100, for example, by a snap fit. The cover 400 has a cover opening 410 that substantially coincides with the fixed opening A2. The cover 400 is configured to restrain a pair of main blades 200a, 200b and a pair of auxiliary blades 300a, 300b in a narrow space between the base 100 and the cover 400. In this embodiment, the pair of auxiliary blades 300a, 300b are interposed between the base 100 and the pair of main blades 200a, 200b. However, in another embodiment, the pair of auxiliary blades 300a, 300b may be interposed between the cover 400 and the pair of main blades 200a, 200b.

[0040] The actuator 500 is configured to move (slide) a pair of main blades 200a, 200b and a pair of auxiliary blades 300a, 300b relative to the base 100. More specifically, as shown in Figure 5, the actuator 500 has a pair of rotatable arms 510a, 510b. Bosses 511a, 511b are provided at the ends of each arm 510a, 510b. In this embodiment, the pair of rotatable arms 510a, 510b are rotatably supported by the base 100. However, in other embodiments, the pair of rotatable arms 510a, 510b may be rotatably supported by any member other than the base 100 in the camera module 1a. The base ends of the rotatable arms 510a, 510b are mechanically connected to a drive unit (not shown), such as a micromotor. By operating the drive unit, the rotatable arms 510a and 510b can be rotated clockwise or counterclockwise in Figure 5. In this embodiment, the first arm 510a and the second arm 510b of the pair of rotatable arms are configured to rotate in opposite directions to each other.

[0041] As can be seen from Figure 5, a pair of main blades 200a and 200b have their respective cam grooves 220a and 220b. Similarly, a pair of auxiliary blades 300a and 300b have their respective cam grooves 320a and 320b. Each of the cam grooves 220a and 220b consists of two straight sections connected at an angle to each other, although this is not limited to them. Of these two straight sections, the straight section that intersects the symmetrical central axis X1 of the main blades 200a and 200b is arranged parallel to the side edges (vertical edges) 230a and 230b of the main blades 200a and 200b. Each of the cam grooves 320a and 320b consists of one intermediate straight section and two end sections connected at an angle to both ends of this intermediate straight section, although this is not limited to them. The intermediate portions of the cam grooves 320a and 320b are positioned parallel to the side edges (vertical edges) 360a and 360b of the auxiliary blades 300a and 300b. In addition, the two end portions of the cam grooves 320a and 320b are inclined in the same direction.

[0042] The bosses 511a and 511b of the rotatable arms 510a and 510b are configured to accommodate both the cam grooves 220a and 220b of the main blades 200a and 200b and the cam grooves 320a and 320b of the auxiliary blades 300a and 300b. As will be described in more detail later, the rotation of the arms 510a and 510b is converted into linear motion (i.e., horizontal sliding motion in Figure 5) of the main blades 200a and 200b and the auxiliary blades 300a and 300b by the cam grooves 220a and 220b of the main blades 200a and 200b and the cam grooves 320a and 320b of the auxiliary blades 300a and 300b. In this embodiment, when a pair of main blades 200a, 200b and a pair of auxiliary blades 300a, 300b move in a linear direction, the first arm 510a and the second arm 510b of a pair of rotatable arms rotate in opposite directions to each other.

[0043] In addition to the main blades 200a, 200b and auxiliary blades 300a, 300b, the cover 400 also has a pair of cam grooves 420a, 420b. These cam grooves 420a, 420b extend substantially obliquely from the vicinity of the corners of the cover opening 410 of the cover 400. In particular, in this embodiment, the cam grooves 420a, 420b extend along a portion of an arc having a predetermined curvature. As can be seen in Figure 3, while the VA device 10 is operating, the bosses 511a, 511b of the rotatable arms 510a, 510b are configured to be able to enter the cam grooves 420a, 420b of the cover 400. On the other hand, the cam grooves 220a and 220b of the main blades 200a and 200b, and the cam grooves 320a and 320b of the auxiliary blades 300a and 300b, constantly house (restrain) the bosses 511a and 511b of the rotatable arms 510a and 510b.

[0044] As will be explained in more detail later, in this embodiment, when a pair of main blades 200a, 200b and a pair of auxiliary blades 300a, 300b are closest together, each of the auxiliary blades 300a, 300b protrudes outward beyond the side edges (vertical edges) 230a, 230b of the main blades 200a, 200b. Here, the side edges refer to edges perpendicular to the longitudinal or horizontal edges 130a, 130b of the base 100. Furthermore, in this embodiment, when the pair of auxiliary blades 300a and 300b move to the closed position (in this position, the minimum opening A3 is defined in cooperation with the recesses 310a and 310b of the pair of auxiliary blades 300a and 300b), the cam grooves 320a and 320b of the auxiliary blades 300a and 300b are covered by the pair of main blades 200a and 200b. Similarly, in this position, the cam grooves 220a and 220b of the main blades 200a and 200b are covered by the pair of auxiliary blades 300a and 300b.

[0045] In this embodiment, when the pair of auxiliary vanes 300a and 300b are moved to the closed position, the pair of rotatable arms 510a and 510b are positioned substantially parallel to the direction of movement of the pair of auxiliary vanes 300a and 300b, i.e., the longitudinal direction of the base 100. Furthermore, in this embodiment, when the pair of rotatable arms 510a and 510b are positioned substantially parallel to the direction of movement of the pair of auxiliary vanes 300a and 300b, the pair of rotatable arms 510a and 510b are hidden behind the pair of auxiliary vanes 300a and 300b.

[0046] As described above, the VA device 10 can be in an open state and a closed state. In the open state, all of the pair of main blades 200a, 200b and the pair of auxiliary blades 300a, 300b are positioned outside the cover opening 410 of the cover 400, and therefore outside the fixed opening A2, and the shape of the fixed opening is also determined by the cover opening 410 of the cover 400. When the VA device 10 is operated to the closed state, the rotation of the rotatable arm 510a drives the main blades 200a and auxiliary blades 300a to predetermined positions along the blade guides 120a, 120b of the base 100, and the rotation of the rotatable arm 510b drives the main blades 200b and auxiliary blades 300b to predetermined positions along the blade guides 120a, 120b of the base 100. On the other hand, when the VA device 10 is operated to open, the rotation of the rotatable arm 510a drives the main blade 200a and auxiliary blade 300a to predetermined positions along the blade guides 120a and 120b of the base 100, and the rotation of the rotatable arm 510b drives the main blade 200b and auxiliary blade 300b to predetermined positions along the blade guides 120a and 120b of the base 100. As described above, such linear sliding motion of the pair of main blades 200a, 200b and the pair of auxiliary blades 300a, 300b is caused by the interaction between the bosses 511a, 511b of the rotatable arms 510a, 510b and the cam grooves 220a, 220b, 320a, 320b of the blades 200a, 200b, 300a, 300b.

[0047] The operation, functions, and advantages of the VA device 10 described above will be explained below with reference to Figures 6 to 12.

[0048] Key Point 1 Figure 6 schematically shows the fixed opening and central opening formed in a conventional VA device 10', and Figure 7 schematically shows the fixed opening and central opening formed in the VA device 10 as described above. In Figure 6, the blades for forming the central opening A1' and fixed opening A2' are indicated by reference numerals "2000a" and "2000b", and in Figure 7, the blades for forming the central opening A1 and fixed opening A2 (i.e., the main blades) are indicated by reference numerals "200a" and "200b". Generally, in order to miniaturize a VA device, it is necessary to shorten the rear portion of the blades for forming the central opening in its sliding direction (i.e., the horizontal direction in Figures 6 and 7). By shortening the rear portions of these blades, the space required to house the open blades can be reduced, and as a result, the VA device can be miniaturized. However, in the conventional structure, if the rear portions of blades 2000a and 2000b are shortened, the VA device 10' cannot operate as intended. This is because, in the closed state of the VA device 10', an undesirable hole H appears in addition to the central opening A1'. This means that the rear portions of the blades 2000a and 2000b must be large enough to prevent this phenomenon. Therefore, in the conventional VA device 10', there was a limit to how much the VA device could be miniaturized. In contrast, in this embodiment, a pair of auxiliary blades 300a and 300b are added to the VA device 10. Basically, as with the conventional structure, in the closed state of the VA device 10 with shortened main blades 200a and 200b, an undesirable hole inevitably occurs in addition to the central opening A1. However, as can be seen from Figure 7, the pair of auxiliary blades 300a and 300b completely cover these undesirable holes. Therefore, in this embodiment, there is no problem caused by shortening the blades. For this reason, in this embodiment, the VA device 10 can be made smaller than in the conventional design.

[0049] Key point 2 Figure 8 schematically shows the relationship between arm stroke and blade stroke in a conventional VA device, and Figure 9 schematically shows the relationship between arm stroke and blade stroke in the VA device 10 described above. In the conventional structure, arms 5010a and 5010b rotate on the base 1000 about a rotation axis and drive blades 2100a and 2100b. Therefore, the line connecting the arm tips (i.e., bosses) 5011 in the open and closed states is approximately parallel to the direction of blade movement. This means that the arm stroke S1' from the open state to the closed state is approximately the same as the blade stroke S2' from the open state to the closed state. In contrast, in this embodiment, similar to the conventional structure, arms 510a and 510b rotate on the base 100 about a rotation axis, but as shown in Figure 9, the straight line L connecting the arm tips (i.e., bosses 511a and 511b) in the open and closed states forms a certain angle with respect to the direction of blade movement, for example, about 45 degrees. In addition, in this embodiment, the rotational motion of arms 510a and 510b is converted into linear motion of blades 200a, 200b, 300a, and 300b by cam grooves 220a, 220b, 320a, and 320b formed in the blades 200a, 200b, 300a, and 300b. By adopting such a structure, in this embodiment, the width (horizontal) component S of the arm stroke S1 from the open state to the closed state is... 1X This can be made shorter than the blade stroke S2 ​​from the open state to the closed state. Therefore, in this embodiment, the width dimension of the VA device can be made smaller than in conventional designs.

[0050] Key point 3 Figure 10 schematically shows the AV device 10 according to this embodiment in the open and closed states, as viewed from the rear side (i.e., the lens side of the camera module). In the open state, the opening shape is determined by the cover opening 410 of the cover 400 (which substantially coincides with the fixed opening A2). In this state, all of the blades 200a, 200b, 300a, 300b and the arms 510a, 510b are located outside the fixed opening A2. On the other hand, in the closed state, the blades 200a, 200b, 300a, 300b are driven inward from the fixed opening A2. In this state, the central opening A1, defined by the inner diameters of the recesses 210a, 210b of the main blades 200a, 200b, determines the opening shape in the closed state. Also in this state, the arms 510a, 510b are positioned inside the fixed opening A2. In this embodiment, a unique structure is adopted in which, when the device is closed, a portion of the actuator 500, namely the arms 510a and 510b that drive the blades 200a, 200b, 300a, and 300b, enters the inside of the fixed opening A2. This allows the arms 510a and 510b to be positioned closer to the center of the device 10. As a result, the size of the VA device can be made smaller. In addition, since the portion of the arms 510a and 510b that enters the inside of the fixed opening A2 when the device is closed is covered by the blades 200a, 200b, 300a, and 300b, the arms 510a and 510b do not affect the optical performance and other functions of the VA device. Furthermore, the arms 510a and 510b do not impair the appearance (cosmetic quality) of the VA device. This is because the arms 510a and 510b are covered by the blades 200a, 200b, 300a, and 300b and are therefore not visible from the front.

[0051] Key Point 4 Figure 11 schematically shows the positional relationship of each blade in the closed state of this embodiment as viewed from the front, and Figure 12 schematically shows the positional relationship of each blade in the closed state of a comparative example in which the shape of the cam groove is not appropriate, as viewed from the front. For clarity, the main blades 200a and 200b are made semi-transparent. As described above, the central opening A1, defined by the inner diameters of the recesses 210a and 210b of the main blades 200a and 200b, determines the shape of the opening in the closed state. Each blade has a cam groove formed therein, and a boss provided at the tip of the arm fits into each cam groove. In this embodiment, in the closed state, the cam groove 220a of the main blade 200a is covered by the auxiliary blade 300a located behind the main blade 200a. On the other hand, the cam groove 320a of the auxiliary blade 300a is covered by the main blade 200a located in front of the auxiliary blade 300a. Similarly, the cam groove 220b of the main blade 200b is covered by the auxiliary blade 300b located behind the main blade 200b. On the other hand, the cam groove 320b of the auxiliary blade 300b is covered by the main blade 200b located in front of the auxiliary blade 300b. Thus, in this embodiment, the shape and position of the cam grooves 220a, 220b, 320a, 320b of each blade are arranged so that one particular groove is reliably covered by the other blade. Therefore, in this embodiment, when closed, it is prevented that undesirable holes appear around the central opening A1. On the other hand, if the shape and / or position of the cam grooves are not appropriate, in other words, if the cam grooves are not covered by any blade, the VA device 10'' cannot function properly because undesirable holes H will be created when closed, as shown in Figure 12.

[0052] As can be understood from the above description, the larger aperture size and shape in the open state represent a significant contribution to miniaturization of VA devices, as achieved by the present invention. Therefore, the VA device according to the present invention is particularly suitable for large-aperture lenses (bright F-numbers). Furthermore, since the basic structure of the above embodiment, in which an actuator rotates the arm and the arm linearly drives each blade, is the same as that of conventional devices, the reliability of the VA device according to the embodiment of the present invention is equivalent to that of conventional devices. Therefore, a small VA device with sufficiently high reliability can be realized. Here again, the VA device according to a preferred embodiment of the present invention brings about the above advantages by having the following features. 1. The rear portion of the main blade that determines the opening shape in the closed state is shortened, and at the same time, an additional blade is positioned to cover the gap (hole) between the fixed opening (i.e., the opening in the open state) and the main blade. 2. The straight line connecting the boss at the tip of the arm in the open and closed states forms a certain angle with respect to the sliding direction of the blade. 3. A part of the actuator, such as an arm, enters the inside of a fixed opening (i.e., an opening in the open state) when it is closed. 4. The shape and position of the cam grooves of some of the blades are arranged so that they are covered by other blades when closed.

[0053] In the following, alternative embodiments of the present invention will be described in detail with reference to Figures 13 to 15. In Figures 13 to 15, components that are the same or substantially the same as those in the embodiments described above are denoted by the same reference numerals and their descriptions are omitted. Figure 13 is an exploded perspective view showing a VA device 10 according to an alternative embodiment of the present invention. As can be seen from Figure 13, the VA device 10 also comprises a base 100, a pair of main blades 200a, 200b, a pair of auxiliary blades 300a, 300b, a cover 400, and an actuator 500 including rotatable arms 510a, 510b.

[0054] In addition to these components, this alternative VA device 10 further comprises a pair of secondary auxiliary vanes 600a, 600b. These secondary auxiliary vanes 600a, 600b are also guided by a pair of vane guides 120a, 120b of the base 100. That is, the pair of secondary auxiliary vanes 600a, 600b are slidably positioned relative to the base 100 so as to move closer to and further apart from each other. Also, the pair of secondary auxiliary vanes 600a, 600b always partially overlap. In this embodiment, the pair of secondary auxiliary vanes 600a, 600b are interposed between the base 100 and the pair of auxiliary vanes 300a, 300b. However, in another embodiment, a pair of auxiliary blades 600a, 600b may be interposed between a pair of auxiliary blades 300a, 300b and a pair of main blades 200a, 200b, or between a pair of main blades 200a, 200b and the cover 400.

[0055] Each of the secondary auxiliary vanes 600a and 600b has a U-shaped recess 610a and 610b, respectively. The recesses 610a and 610b work together to define a minimum opening A5 surrounding the central opening A1 when the pair of secondary auxiliary vanes 600a and 600b are closest to each other (see Figure 15). These two recesses 610a and 610b also work together to define a maximum opening A6 that substantially coincides with (or surrounds, in another embodiment) the fixed opening A2 when the pair of secondary auxiliary vanes 600a and 600b are furthest apart from each other (see Figure 15).

[0056] As can be seen in Figure 13, in this embodiment, a pair of secondary auxiliary vanes 600a and 600b each have linear cam grooves 620a and 620b. Each of the cam grooves 620a and 620b is positioned parallel to the side edges (vertical edges) 630a and 630b of the secondary auxiliary vanes 600a and 600b. The bosses 511a and 511b of the rotatable arms 510a and 510b are further housed within the cam grooves 620a and 620b of the secondary auxiliary vanes 600a and 600b. The rotation of the arms 510a and 510b is converted into linear motion by the cam grooves 620a and 620b of the secondary auxiliary vanes 600a and 600b. In other words, a pair of secondary auxiliary blades 600a, 600b are driven together with a pair of main blades 200a, 200b and a pair of auxiliary blades 300a, 300b by rotatable arms 510a, 510b.

[0057] As can be seen from Figure 14, the pair of main blades 200a and 200b in this alternative embodiment are modified from the pair of main blades in the previously described embodiment. More specifically, in this alternative embodiment, a portion of the side edges (vertical edges) 230a and 230b of the aforementioned main blades 200a and 200b is cut at an angle. As a result, the length of the upper part in the longitudinal direction (horizontal direction) of each main blade 200a and 200b is shorter than the length of the lower part in the longitudinal direction. Furthermore, the cam grooves 220a and 220b of the main blades 200a and 200b are changed to a straight shape.

[0058] In this embodiment, each of the secondary auxiliary blades 600a and 600b is configured to protrude outward from the side edges 230a and 230b of the main blades 200a and 200b when the pair of main blades 200a and 200b, the pair of auxiliary blades 300a and 300b, and the pair of secondary auxiliary blades 600a and 600b are closest to each other. As a result of having such a distinctive configuration, this modified form has the following effects.

[0059] In this alternative embodiment, the rear portions 240a, 240b of the main blades 200a, 200b are shortened compared to the first embodiment to save more space for housing various blades in the open state (see Figure 14). The contour of the rear portion of the blades in the first embodiment is shown by dashed lines. However, simply shortening the rear portions 240a, 240b of the main blades 200a, 200b would prevent the main blades 200a, 200b from covering part of the cam grooves 320a, 320b of the auxiliary blades 300a, 300b. That is, an undesirable hole H is formed outside the central opening A1 that allows light to pass through (see the shaded area in Figure 15). In this state, the VA device 10 cannot perform its intended function. In this alternative embodiment, to overcome this incidental drawback, a pair of secondary auxiliary blades 600a, 600b are added to cover the undesirable hole H. By adapting this structure, the space required to house the various blades can be reduced compared to the first embodiment, and therefore the VA device 10 can be made even smaller.

[0060] Preferred embodiments of the present invention have been described above with reference to the relevant drawings. However, the present invention is not limited to these embodiments, and various modifications and changes can be made to the above embodiments without departing from the spirit of the invention, and these are also included within the scope of the present invention. [Explanation of symbols]

[0061] 1. Portable electronic devices, products 1a Camera module 10, 10', 10" Variable aperture device (VA device) 100 base 110 Base opening 120a, 120b blade guide 130a, 130b edges 200a, 200b Main blades 210a, 210b recess 220a, 220b cam groove 230a, 230b side edge 240a, 240b Rear of the wing 250a1, 250a2, 250b1, 250b2 fingers 300a, 300b auxiliary blades 310a, 310b recess 320a, 320b cam groove 340a, 340b Rear of the wing 350a1, 350a2, 350b1, 350b2 fingerings 360a, 360b side edge 400 Cover 410 Cover opening 420a, 420b cam groove 500 Actuators 510a Rotatable arm (first arm) 510b Rotatable arm (second arm) 511a, 511b Boss 600a, 600b Secondary auxiliary blades 610a, 610b recess 620a, 620b cam groove 630a,630b side edge 2000a, 2000b blades 2100a, 2100b blades 5010a, 5010b Arm A1, A1' center opening A2, A2' Fixed opening A3 minimum opening A4 maximum opening A5 minimum opening A6 maximum opening C Casing H hole L straight line S1, S1' Arm stroke S2, S2' Feather stroke S 1x Arm stroke width component

Claims

1. A variable aperture device (10) for a camera module (1a), A base (100) having a base opening (110) and a pair of blade guides (120a, 120b), wherein the pair of blade guides (120a, 120b) are provided on mutually opposing longitudinal edges (130a, 130b) of the base (100) having the base opening (110) between them, A pair of main blades (200a, 200b) are guided by the pair of blade guides (120a, 120b) of the base (100), wherein the pair of main blades (200a, 200b) are slidably arranged relative to the base (100) so as to move closer to and further apart from each other, and each of the main blades (200a, 200b) has a recess (210a, 210b), the recess (210a, 210b) having a central opening (A) when the pair of main blades (200a, 200b) are closest to each other. １ ) collaboratively define the fixed opening (A) when the pair of main blades (200a, 200b) are furthest apart from each other. ２ A pair of main blades (200a, 200b) work together to define the area, A pair of auxiliary blades (300a, 300b) are guided by the pair of blade guides (120a, 120b) of the base (100), wherein the pair of auxiliary blades (300a, 300b) are slidably arranged with respect to the base (100) so as to move closer to and further apart from each other, and each of the auxiliary blades (300a, 300b) has a recess (310a, 310b), the recess (310a, 310b) is such that when the pair of auxiliary blades (300a, 300b) are closest to each other the central opening (A １ The smallest opening (A) surrounding ) ３ ) collaboratively define the fixed opening (A) when the pair of auxiliary blades (300a, 300b) are furthest apart from each other. ２ The maximum opening (A) substantially coincides with ) ４ A pair of auxiliary blades (300a, 300b) work together to define the area, Fixed to the base (100), and the fixing opening (A ２ A cover (400) having a cover opening (410) substantially corresponding to the base (100), the cover (400) configured to restrain the pair of main blades (200a, 200b) and the pair of auxiliary blades (300a, 300b) in the space between the base (100) and the cover (400), An actuator (500) for moving the pair of main blades (200a, 200b) and the pair of auxiliary blades (300a, 300b) relative to the base (100), Equipped with, Each of the auxiliary blades (300a, 300b) is configured to protrude outward from the side edges (230a, 230b) of the main blades (200a, 200b) that are perpendicular to the longitudinal edges (130a, 130b) of the base (100) when the pair of main blades (200a, 200b) are closest to each other and the pair of auxiliary blades (300a, 300b) are closest to each other. Variable aperture device (10).

2. The variable aperture device (10) according to claim 1, wherein the pair of auxiliary blades (300a, 300b) are interposed between the base (100) and the pair of main blades (200a, 200b).

3. The actuator (500) includes a pair of rotatable arms (510a, 510b) with bosses (511a, 511b) at their tips, the pair of main blades (200a, 200b) each having cam grooves (220a, 220b), the pair of auxiliary blades (300a, 300b) each having cam grooves (320a, 320b), and the bosses (511a, 511b) of the rotatable arms (510a, 510b) are located at the cam grooves (220a, 220b) of the main blades (200a, 200b) A variable aperture device (10) according to claim 1, wherein the rotatable arms (510a, 510b) are configured to be housed in the cam grooves (320a, 320b) of the main blades (200a, 200b) and the auxiliary blades (300a, 300b), and the rotation of the rotatable arms (510a, 510b) is converted into linear motion of the main blades (200a, 200b) and the auxiliary blades (300a, 300b) by the cam grooves (220a, 220b) of the main blades (200a, 200b) and the cam grooves (320a, 320b) of the auxiliary blades (300a, 300b).

4. The variable aperture device (10) according to claim 3, wherein the pair of rotatable arms (510a, 510b) are rotatably supported on the base (100).

5. The variable aperture device (10) according to claim 3, wherein the cover (400) has a pair of cam grooves (420a, 420b), and the bosses (511a, 511b) of the rotatable arms (510a, 510b) are configured to enter the cam grooves (420a, 420b) of the cover (400).

6. The recesses (310a, 310b) of the pair of auxiliary blades (300a, 300b) create the minimum opening (A ３ The variable aperture device (10) according to claim 3, wherein when the pair of auxiliary blades (300a, 300b) move to a closed position defined by the cooperation of the two main blades (200a, 200b), the cam grooves (320a, 320b) of the auxiliary blades (300a, 300b) are covered by the pair of main blades (200a, 200b), and the cam grooves (220a, 220b) of the main blades (200a, 200b) are covered by the pair of auxiliary blades (300a, 300b).

7. When the pair of auxiliary vanes (300a, 300b) move to a closed position defined by the concave portions (310a, 310b) of the pair of auxiliary vanes (300a, 300b) and cooperate to define the minimum opening (A ３ ), the pair of rotatable arms (510a, 510b) are in a position substantially parallel to the moving direction of the pair of auxiliary vanes (300a, 300b). The variable aperture device (10) according to claim 3.

8. The variable aperture device (10) according to claim 7, wherein when the pair of rotatable arms (510a, 510b) are positioned substantially parallel to the direction of movement of the pair of auxiliary vanes (300a, 300b), the pair of rotatable arms (510a, 510b) are hidden behind the pair of auxiliary vanes (300a, 300b).

9. The variable aperture device (10) according to claim 3, wherein when the pair of main blades (200a, 200b) and the pair of auxiliary blades (300a, 300b) move in a straight line, the first arm (510a) and the second arm (510b) of the pair of rotatable arms (510a, 510b) rotate in opposite directions to each other.

10. The variable aperture device (10) further comprises a pair of secondary auxiliary vanes (600a, 600b) guided by a pair of vane guides (120a, 120b) of the base (100), the pair of secondary auxiliary vanes (600a, 600b) being slidably arranged relative to the base (100) to move toward and away from each other, each of the secondary auxiliary vanes (600a, 600b) having a recess (610a, 610b), the recess (610a, 610b) being the central opening (A) when the pair of secondary auxiliary vanes (600a, 600b) are closest to each other １ The smallest opening (A) surrounding ) ５ ) collaboratively define the fixed opening (A) when the pair of secondary auxiliary vanes (600a, 600b) are furthest apart from each other. ２ The largest opening (A) surrounding or substantially matching ) ６ The variable aperture device (10) according to claim 3, wherein the two secondary auxiliary vanes (600a, 600b) work together to define the two secondary auxiliary vanes (600a, 600b), and each of the two secondary auxiliary vanes (600a, 600b) is configured to protrude outward from the side edges (230a, 230b) of the two main vanes (200a, 200b) that are perpendicular to the longitudinal edges (130a, 130b) of the base (100) when the pair of main vanes (200a, 200b) are closest to each other, the pair of auxiliary vanes (300a, 300b) are closest to each other, and the pair of secondary auxiliary vanes (600a, 600b) are closest to each other.

11. The variable aperture device (10) according to claim 10, wherein the pair of secondary auxiliary vanes (600a, 600b) each have a cam groove (620a, 620b), and the bosses (511a, 511b) of the rotatable arms (510a, 510b) are configured to be further housed within the cam grooves (620a, 620b) of the secondary auxiliary vanes (600a, 600b), and the rotation of the rotatable arms (510a, 510b) is converted into linear motion of the secondary auxiliary vanes (600a, 600b) by the cam grooves (620a, 620b) of the secondary auxiliary vanes (600a, 600b).

12. The variable aperture device (10) according to claim 10, wherein the pair of secondary auxiliary vanes (600a, 600b) are interposed between the base (100) and the pair of auxiliary vanes (300a, 300b).

13. The central opening (A １ The variable aperture device (10) according to claim 1, wherein the diameter is circular.

14. An electronic device (1) including a camera module (1a), wherein the camera module (1a) comprises a variable aperture device (10) according to any one of claims 1 to 13.

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