Variable aperture device for camera module and product including 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 for use in a camera module or camera unit in a variety of products, and in particular to a variety of portable electronic devices including smartphones, mobile phones, etc. The present invention also relates to products including such a variable aperture device. [Background technology]

[0002] In recent years, variable aperture devices have been attracting attention in camera modules for smartphones and other mobile devices in order to achieve higher image quality. In addition, some smartphones have begun to adopt a "macro photography function."

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

[0004] With regard to camera specifications, there is an increasing demand for larger apertures (brighter F-numbers), and this has led to a demand for larger apertures in variable apertures as well.

[0005] However, a large-diameter variable diaphragm increases the size of the variable diaphragm device itself, leading to an increase in the size of the camera module.

[0006] As a variable aperture device structure that meets the demand for miniaturization, a structure in which one actuator drives two blades has been proposed, as disclosed in Japanese Patent Laid-Open Publication No. 2017-167186. In this structure, the variable aperture is achieved by controlling the opening and closing of the two blades. In addition, in this structure, an arm is mechanically connected to a drive unit, and the two blades can be driven simultaneously by moving (particularly, rotating) the arm. This makes it possible to save space for the actuator for opening and closing the two blades, and reduce the size (particularly, its width) of the variable aperture device.

[0007] On the other hand, Japanese Patent Application Laid-Open No. 2021-056448 proposes a structure using a shape memory alloy element (hereinafter referred to as "SMA element") as an actuator that drives the blade. SMA elements are generally known as small actuators. In Japanese Patent Application Laid-Open No. 2021-056448, the size of the actuator is sufficiently small so that the SMA elements are arranged overlapping each other in the thickness direction of the blade. Therefore, the variable aperture device can be miniaturized.

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

[0009] In the structure disclosed in JP 2017-167186 A, the size of the blade back must be large enough so that no holes other than the central hole are exposed in the closed state, which requires a large space to store the blades in the open state, resulting in an increase in the size of the variable aperture device.

[0010] On the other hand, the structure disclosed in JP 2021-056448 A uses a small SMA element 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 blade is greatly limited. For this reason, it is difficult to apply the SMA element to a large-diameter variable aperture device that requires a long blade stroke. In addition, the solution disclosed in JP 2021-056448 A, like the solution disclosed in JP 2017-167186 A, cannot solve the problem of the large size of the variable aperture device caused by the size of the rear blade of the blade.

[0011] In summary, the problem with the structure disclosed in JP 2017-167186 A is that the size of the rear blade portion of the blade must be sufficiently large, which not only causes the variable iris device to become undesirably large, but also significantly limits the blade stroke.

[0012] For these reasons, there is a need for a variable aperture device for a camera module that is smaller than prior art devices, but has a reliability level equal to or greater than that of the larger prior art devices. Summary of the Invention

[0013] In view of the above, it is an object of the present invention to provide a novel variable aperture device for a camera module that overcomes or at least mitigates the above-mentioned problems associated with prior art devices. In particular, it is a more specific object of the present invention to provide a novel variable aperture device for a camera module that is smaller than prior art devices and has a reliability level equal to or greater than that of larger prior art devices. [Means for solving the problem]

[0014] To achieve these objects, 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 opposing longitudinal edges of the base having the base opening therebetween; (ii) a pair of main blades guided by the pair of blade guides of the base, the pair of main blades being slidably disposed relative to the base so as to move toward and away from each other, each of the main blades having a recess (notch), the recesses cooperatively defining 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 from each other; and (iii) a pair of main blades guided by the pair of blade guides of the base. (iv) a cover fixed to the base, the cover having a cover opening substantially matching the fixed opening, the cover being configured to restrain the pair of main blades and the pair of auxiliary blades in a space between the base and the cover; and (v) an actuator for moving the pair of main blades and the 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 and the pair of auxiliary blades are closest to each other, each of the auxiliary blades is configured to protrude outward from a side edge of the main blade that is perpendicular to a longitudinal edge of the base.

[0015] The present invention also provides an article of manufacture 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. Therefore, it is possible to avoid a problem that occurs when the size of the main blade is shortened in its sliding direction (i.e., the longitudinal or horizontal direction), namely, the occurrence of an undesirable hole that allows light to pass around the central opening of the variable aperture device. This is because the auxiliary blades can cover such an undesirable hole in the protruding state. In other words, according to the present invention, by shortening the longitudinal (horizontal) length of the rear end of the main blade, the variable aperture device can be made smaller, particularly in the longitudinal or horizontal direction, compared to any conventional device without the occurrence of an undesirable hole. This is because shortening the longitudinal length of the rear end of the main blade effectively saves the space required for storing the main blade in the open state.

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

[0018] According to a preferred aspect of the present invention, the actuator includes a pair of rotatable arms with bosses at their tips, each of which has a pair of main blades and a pair of auxiliary blades, each of which has a cam groove, and the bosses of the rotatable arms are configured to be received in the cam grooves of the main blades and the auxiliary blades, and rotation of the rotatable arms is converted into linear motion of the main blades and the auxiliary blades by the cam grooves of the main blades and the cam grooves of the auxiliary blades. In this preferred aspect of the present invention, the pair of rotatable arms may be rotatably supported by a base. This aspect achieves a particularly simple and reliable structure. Also, in a 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 be able to enter the cam grooves of the cover.

[0019] According to a preferred embodiment of the present invention, when the pair of auxiliary blades move to a closed position in which the recesses of the pair of auxiliary blades cooperate to define a minimum opening, 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] According to a preferred embodiment of the present invention, when the pair of auxiliary blades are moved to a closed position in which the recesses of the pair of auxiliary blades jointly define a minimum opening, the pair of rotatable arms are positioned substantially parallel to the direction of movement of the pair of auxiliary blades. In this preferred embodiment of the present invention, when the pair of rotatable arms are positioned substantially parallel to the direction of movement of the pair of auxiliary blades, the pair of rotatable arms can be hidden behind the pair of auxiliary blades. This embodiment allows for a particularly compact structure of the device.

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

[0022] According to a preferred aspect of the present invention, the variable aperture device further includes a pair of secondary auxiliary vanes guided by a pair of vane guides on the base, the pair of secondary auxiliary vanes being slidably arranged relative to the base so as to move toward and away from each other, each having a recess that cooperatively defines a minimum opening surrounding the central opening when the pair of secondary auxiliary vanes are closest to each other and a maximum opening that surrounds or substantially coincides with the fixed opening when the pair of secondary auxiliary vanes are furthest from each other, and each of the pair of secondary auxiliary vanes is configured to protrude outward from a side edge (vertical edge) of the main vane that is 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 aspect, the area of the portion of the main vane opposite to the side where the recess is formed (i.e., the "blade rear portion") can be made smaller. This contributes to further miniaturization of the device.

[0023] According to a preferred embodiment of the present invention, each of the pair of secondary auxiliary blades has a cam groove, and the boss of the rotatable arm is further configured to be received in the cam groove of the secondary auxiliary blade, so that the rotation of the arm is converted into linear motion of the secondary auxiliary blade by the cam groove of the secondary auxiliary blade. This embodiment also realizes a particularly compact structure.

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

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

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

[0027] Non-limiting exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a schematic diagram of a product, namely a smartphone, incorporating a camera module including a variable aperture device according to an embodiment of the present invention; [Figure 2]2 is a perspective view of the variable aperture device of the camera module shown in FIG. 1 in an open state. [Figure 3] 3 is a front view of the variable aperture device shown in FIG. 2 in an open state. [Figure 4] 3 is a front view of the variable aperture device shown in FIG. 2 in a closed state. [Figure 5] FIG. 5 is an exploded perspective view of the variable aperture device shown in FIGS. 2 to 4. [Figure 6] 1 is a schematic diagram of a fixed aperture and a central aperture formed in a conventional variable aperture device, with the cover of the device removed for clarity; [Figure 7] FIG. 6 is a schematic diagram of the fixed apertures and central aperture formed in the variable aperture device shown in FIGS. 2 to 5, with the cover of the device removed for clarity. [Figure 8] FIG. 1 is a diagram illustrating the relationship between arm stroke and vane stroke in a conventional variable aperture device, with the cover of the device removed for clarity. [Figure 9] FIG. 6 is a diagram showing a schematic representation of the relationship between arm stroke and blade stroke in the variable aperture device shown in FIGS. 2 to 5, with the cover of the device removed for clarity. [Figure 10] 6A and 6B are diagrams schematically illustrating the variable diaphragm device shown in FIGS. 2 to 5 in an open state and a closed state, as viewed from the back side (ie, the lens side of the camera module). [Figure 11] FIG. 6 is a diagram schematically showing the positional relationship between the blades of the variable diaphragm device shown in FIGS. 2 to 5 in a closed state, as viewed from the front side. [Figure 12] FIG. 10 is a diagram showing, as viewed from the front side, a schematic view of the positional relationship of each blade in a closed state in a comparative example in which the shape of the cam groove is inappropriate. [Figure 13] FIG. 10 is an exploded perspective view of a variable aperture device according to another embodiment of the present invention. [Figure 14] FIG. 14 is a plan view showing a modified shape of the main blade of the variable aperture device shown in FIG. 13. [Figure 15]14 is a front view of a reference example for explaining the effect brought about by the variable aperture device shown in FIG. 13. FIG. DETAILED DESCRIPTION OF THE INVENTION

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

[0030] As used herein, directional terms such as "front," "back," "side," "up," "down," "superior," "lower," "upper," "lower," "upper," "lower," "right," "left," "longitudinal," "lateral," "horizontal," "vertical," and the like, are to be understood with reference to the orientation of the device in the figures, which may or may not correspond to the orientation in actual use.

[0031] The following exemplary embodiments of the present invention relate to portable electronic devices, particularly, but not limited to, variable aperture devices used in camera modules of products such as smartphones. Furthermore, the following exemplary embodiments of the present invention relate to such products, particularly portable electronic devices with camera modules including variable aperture devices, which is one exemplary embodiment of the present invention. However, such products may be any device, any apparatus, any equipment, any machine, any facility, any tool, etc. that includes a camera module.

[0032] 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] Fig. 2 is a perspective view showing a VA device 10 built into the camera module 1a shown in Fig. 1. Fig. 3 is a front view showing the same VA device 10. The VA device 10 is in an "open state" in Figs. 2 and 3. That is, in the state shown in Figs. 2 and 3, a fixed opening A2 (details of which will be described later) is realized in the VA device 10.

[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 of which will be described later).

[0035] Fig. 5 is an exploded perspective view showing the VA device 10. As can be seen from Fig. 5, the VA device 10 mainly includes a base 100, a pair of main blades 200a, 200b, a pair of auxiliary blades 300a, 300b, a cover 400, and an actuator 500. The base 100 and the cover 400 cooperate to form a rectangular casing C for storing the pair of main blades 200a, 200b, the pair of auxiliary blades 300a, 300b, and a rotatable arm of the actuator 500 (described in detail below). The main body (i.e., the drive unit) of the actuator 500 is not shown, but may be embodied by, for example, a micromotor, in particular 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 shape and size. The pair of blade guides 120a, 120b are provided on opposing longitudinal (horizontal) edges 130a, 130b of the base 100, sandwiching the base opening 110 therebetween. The pair of blade guides 120a, 120b extend parallel to each other.

[0037] The pair of primary blades 200a, 200b are guided by a pair of blade guides 120a, 120b on the base 100. That is, the pair of primary blades 200a, 200b are slidably arranged relative to the base 100 so as to move toward and away from each other. The pair of primary blades 200a, 200b always partially overlap each other. As can be seen from FIG. 5, each of the primary blades 200a, 200b has a generally U-shape as a whole. More specifically, each of the primary blades 200a, 200b includes a blade rear portion (i.e., base portion) 240a, 240b and a pair of fingers 250a1, 250a2, 250b1, 250b2 extending from both ends of the respective blade rear portions 240a, 240b. As a result, each of the primary blades 200a, 200b has a recess 210a, 210b, respectively. The recess 210a, 210b includes a wide region involved in forming the fixed opening A2 and a semicircular region involved in forming the central opening A1, the semicircular region extending from the wide region to the respective blade rear ends 240a, 240b. Therefore, these two recesses 210a, 210b cooperate to define the central opening A1 when the pair of primary blades 200a, 200b are closest to each other. In this embodiment, the central opening A1 jointly defined by the recesses 210a, 210b is circular. Furthermore, the recesses 210a, 210b cooperate to define the fixed opening A2 when the pair of primary blades 200a, 200b are farthest from each other.

[0038] The pair of auxiliary blades 300a, 300b are also guided by a pair of blade guides 120a, 120b on the base 100. That is, the pair of auxiliary blades 300a, 300b are slidably arranged relative to the base 100 so as to move toward and away from each other. The pair of auxiliary blades 300a, 300b always partially overlap each other. As can be seen from FIG. 5, each of the auxiliary blades 300a, 300b also has a generally U-shape as a whole. More specifically, each of the auxiliary blades 300a, 300b includes a blade rear portion (i.e., base portion) 340a, 340b and a pair of fingers 350a1, 350a2, 350b1, 350b2 extending from both ends of the respective blade rear portions 340a, 340b. As a result, each of the auxiliary vanes 300a, 300b has a recess 310a, 310b, respectively. These two recesses 310a, 310b cooperate to define a minimum opening A3 (see FIGS. 7 and 10) surrounding the central opening A1 when the pair of auxiliary vanes 300a, 300b are closest to each other. Furthermore, the recesses 310a, 310b cooperate to define a maximum opening A4 (see FIG. 7) when the pair of auxiliary vanes 300a, 300b are furthest from each other. The maximum opening A4 substantially coincides with the fixed opening A2.

[0039] The cover 400 is fixed to the base 100 by, for example, a snap fit. The cover 400 has a cover opening 410 that substantially coincides with the fixing opening A2. The cover 400 is configured to restrain the pair of main blades 200a, 200b and the 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) the pair of main blades 200a, 200b and the pair of auxiliary blades 300a, 300b relative to the base 100. More specifically, as shown in FIG. 5 , the actuator 500 has a pair of rotatable arms 510a, 510b. Bosses 511a, 511b are provided at the tip 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 of the camera module 1a other than the base 100. 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, 510b can be rotated clockwise or counterclockwise in Fig. 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.

[0041] As can be seen from FIG. 5 , each of the pair of main blades 200a, 200b has a respective cam groove 220a, 220b. Similarly, each of the pair of auxiliary blades 300a, 300b has a respective cam groove 320a, 320b. Each of the cam grooves 220a, 220b is composed of, but is not limited to, two straight line segments connected to each other at a certain angle. Of these two straight line segments, the straight line segment that intersects with the symmetrical central axis X1 of the main blades 200a, 200b is arranged parallel to the side edges (vertical edges) 230a, 230b of the main blades 200a, 200b. Each of the cam grooves 320a, 320b is composed of, but is not limited to, one intermediate straight line segment and two end segments connected to both ends of the intermediate straight line segment at a certain angle. The middle portions of the cam grooves 320a, 320b are arranged parallel to the side edges (vertical edges) 360a, 360b of the support blades 300a, 300b, and the two end portions of the cam grooves 320a, 320b are inclined in the same direction as each other.

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

[0043] In addition to the main blades 200a, 200b and the 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 near the corners of the cover opening 410 of the cover 400. Particularly, in this embodiment, the cam grooves 420a, 420b extend along portions of a circular arc having a predetermined curvature. As can be seen from FIG. 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, 220b of the main blades 200a, 200b and the cam grooves 320a, 320b of the support blades 300a, 300b always accommodate (restrain) the bosses 511a, 511b of the rotatable arms 510a, 510b.

[0044] As will be described in detail later, in this embodiment, when the pair of main blades 200a, 200b and the pair of auxiliary blades 300a, 300b are closest to each other, each of the auxiliary blades 300a, 300b protrudes outward from 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, 300b move to the closed position (at this position, the minimum opening A3 is defined by the recesses 310a, 310b of the pair of auxiliary blades 300a, 300b in cooperation with each other), the cam grooves 320a, 320b of the auxiliary blades 300a, 300b are covered by the pair of main blades 200a, 200b. Similarly, at this position, the cam grooves 220a, 220b of the main blades 200a, 200b are covered by the pair of auxiliary blades 300a, 300b.

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

[0046] As described above, the VA device 10 can be in an open state and a closed state. In the open state, the pair of main blades 200 a, 200 b and the pair of auxiliary blades 300 a, 300 b are all disposed 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 be in the closed state, the rotation of the rotatable arm 510 a drives the main blade 200 a and the auxiliary blade 300 a to predetermined positions along the blade guides 120 a, 120 b of the base 100, and the rotation of the rotatable arm 510 b drives the main blade 200 b and the auxiliary blade 300 b to predetermined positions along the blade guides 120 a, 120 b of the base 100. On the other hand, when the VA device 10 is operated to the open state, the rotation of the rotatable arm 510a drives the main blade 200a and the 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 the 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 and 200b and the pair of auxiliary blades 300a and 300b is generated by the interaction between the bosses 511a and 511b of the rotatable arms 510a and 510b and the cam grooves 220a, 220b, 320a, and 320b of the blades 200a, 200b, 300a, and 300b.

[0047] The operation, functions, and advantages of the above-described VA device 10 will be described below with reference to FIGS.

[0048] Key Point 1 FIG. 6 schematically illustrates the fixed openings and central openings formed in a conventional VA device 10′, and FIG. 7 schematically illustrates the fixed openings and central openings formed in the VA device 10 as described above. In FIG. 6, the blades forming the central openings A1′ and A2′ are designated by reference numerals “2000a” and “2000b.” In FIG. 7, the blades forming the central openings A1 and A2 (i.e., the main blades) are designated by reference numerals “200a” and “200b.” Generally, to reduce the size of a VA device, it is necessary to shorten the rear portions of the blades forming the central opening in the sliding direction (i.e., the horizontal direction in FIGS. 6 and 7). By shortening the rear portions of these blades, the space required to store the blades in an open state can be reduced, resulting in a more compact VA device. However, in the conventional structure, shortening the rear portions of the blades 2000a and 2000b prevents the VA device 10′ from operating as intended. This is because, when the VA device 10′ is in the closed state, 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, the conventional VA device 10′ had limitations on miniaturization. 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, when the VA device 10 is in the closed state with the main blades 200a and 200b shortened, an undesirable hole inevitably appears in addition to the central opening A1. However, as can be seen from FIG. 7 , the pair of auxiliary blades 300a and 300b completely cover these undesirable holes. Therefore, in this embodiment, there are no problems with shortening the blades. Therefore, in this embodiment, the VA device 10 can be made smaller than conventional devices.

[0049] Key point 2 FIG. 8 schematically illustrates the relationship between the arm stroke and the blade stroke in a conventional VA device, and FIG. 9 schematically illustrates the relationship between the arm stroke and the blade stroke in the VA device 10 described above. In the conventional structure, arms 5010a and 5010b rotate on base 1000 around a rotation axis to drive blades 2100a and 2100b. Therefore, the line connecting arm tips (i.e., bosses) 5011 in the open and closed states is approximately parallel to the direction of blade movement. This means that arm stroke S1' from the open state to the closed state is approximately the same as blade stroke S2' from the open state to the closed state. In contrast, in this embodiment, arms 510a and 510b rotate on base 100 around a rotation axis, as in the conventional structure. However, as shown in FIG. 9, line L connecting arm tips (i.e., bosses 511a and 511b) in the open and closed states forms a certain angle, for example, approximately 45 degrees, with respect to the direction of blade movement. In addition, in this embodiment, the rotational motion of the arms 510a and 510b is converted into the linear motion of the blades 200a, 200b, 300a, and 300b by the 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 Therefore, in this embodiment, the width of the VA device can be made smaller than that of the conventional VA device.

[0050] Key Point 3 FIG. 10 schematically illustrates 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, the blades 200a, 200b, 300a, and 300b and the arms 510a and 510b are all positioned outside the fixed opening A2. On the other hand, in the closed state, the blades 200a, 200b, 300a, and 300b are driven to the inside of the fixed opening A2. In this state, the central opening A1, defined by the inner diameters of the recesses 210a and 210b of the main blades 200a and 200b, determines the opening shape in the closed state. In this state, the arms 510a and 510b are positioned inside the fixed opening A2. In this embodiment, a unique structure is adopted in which a portion of the actuator 500, i.e., the arms 510a and 510b that drive the blades 200a, 200b, 300a, and 300b, are positioned inside the fixed opening A2 in the closed state. 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 further reduced. In addition, because the portions of the arms 510a and 510b that are positioned inside the fixed opening A2 in the closed state are 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 detract from the appearance (appearance quality) of the VA device. This is because the arms 510a and 510b are covered by the blades 200a, 200b, 300a, and 300b and cannot be seen from the front.

[0051] Key Point 4 FIG. 11 schematically illustrates the positional relationship of each blade in the closed state of this embodiment, as viewed from the front. FIG. 12 schematically illustrates the positional relationship of each blade in the closed state of a comparative example in which the cam groove shape is inappropriate, as viewed from the front. For clarity, the main blades 200a and 200b are 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 is formed with a cam groove, and bosses provided at the ends of the arms fit into the respective cam grooves. 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. As such, in this embodiment, the shape and position of the cam grooves 220a, 220b, 320a, and 320b of each blade are arranged so that a specific groove of one blade is reliably covered by the other blade. Therefore, in this embodiment, an undesirable hole is prevented from appearing around the central opening A1 in the closed state. On the other hand, if the shape and / or position of the cam groove is inappropriate, in other words, if the cam groove is not covered by any blade, the VA device 10″ will not function properly in the closed state due to the undesirable hole H, as shown in FIG. 12 .

[0052] As can be seen from the above description, the larger aperture size and shape in the open state are a significant contribution made by the present invention to the miniaturization of VA devices. 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-described embodiment, in which an actuator rotates an arm and the arm linearly drives each blade, is the same as that of a conventional device, the reliability of the VA device according to the embodiment of the present invention is equivalent to that of a conventional device. Therefore, a compact VA device with sufficiently high reliability can be realized. Again, the VA device according to the preferred embodiment of the present invention provides the above-mentioned advantages by having the following features: 1. The rear part of the main blade, which determines the opening shape in the closed state, is shortened, and at the same time, an additional blade is arranged 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 bosses at the end of the arm in the open and closed states forms a certain angle with the sliding direction of the blades. 3. A part of the actuator, for example an arm, enters inside the fixed opening in the closed state (i.e., the opening in the open state). 4. The shape and position of the cam grooves of some blades are arranged so that they are covered by other blades when closed.

[0053] An alternative embodiment of the present invention will be described in detail below with reference to FIGS. 13 to 15. In FIGS. 13 to 15, components that are the same or substantially the same as those in the above-described embodiment are denoted by the same reference numerals, and their description will be omitted. FIG. 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 FIG. 13, the VA device 10 also includes 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 includes a pair of secondary auxiliary blades 600a, 600b. These secondary auxiliary blades 600a, 600b are also guided by a pair of blade guides 120a, 120b on the base 100. That is, the pair of secondary auxiliary blades 600a, 600b are slidably arranged relative to the base 100 so as to move toward and away from each other. The pair of secondary auxiliary blades 600a, 600b always partially overlap. In this embodiment, the pair of secondary auxiliary blades 600a, 600b are interposed between the base 100 and the pair of auxiliary blades 300a, 300b. However, in another embodiment, the pair of auxiliary blades 600a, 600b may be interposed between the pair of auxiliary blades 300a, 300b and the pair of main blades 200a, 200b, or between the pair of main blades 200a, 200b and the cover 400.

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

[0056] As can be seen from Figure 13, in this embodiment, a pair of secondary support blades 600a, 600b each have a linear cam groove 620a, 620b. Each of the cam grooves 620a, 620b is arranged parallel to the side edges (vertical edges) 630a, 630b of the secondary support blades 600a, 600b. The bosses 511a, 511b of the rotatable arms 510a, 510b are configured to be further received within the cam grooves 620a, 620b of the secondary support blades 600a, 600b. Rotation of the arms 510a, 510b is converted into linear motion by the cam grooves 620a, 620b of the secondary support blades 600a, 600b. That is, the pair of secondary auxiliary blades 600a, 600b are driven by the rotatable arms 510a, 510b together with the pair of main blades 200a, 200b and the pair of auxiliary blades 300a, 300b.

[0057] As can be seen from Fig. 14, the pair of primary blades 200a, 200b in this alternative embodiment are modified from the pair of primary blades in the previously described embodiment. More specifically, in this alternative embodiment, portions of the side edges (vertical edges) 230a, 230b of the previously described primary blades 200a, 200b are cut obliquely. As a result, the length of the upper portion of each primary blade 200a, 200b in the longitudinal direction (horizontal direction) is shorter than the length of the lower portion in the longitudinal direction. Furthermore, the cam grooves 220a, 220b of the primary blades 200a, 200b are modified to be linear.

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

[0059] In this alternative embodiment, the blade rear portions 240a, 240b of the main blades 200a, 200b are shortened compared to the first embodiment to save more space for storing the various blades in the open state (see FIG. 14). The outline of the blade rear portions in the first embodiment is shown in phantom lines. However, simply shortening the blade 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. In other words, an undesirable hole H would be formed outside the central aperture A1 that allows light to pass through (see the shaded area in FIG. 15). In this state, the VA device 10 would not function as intended. In this alternative embodiment, to overcome this drawback, a pair of secondary auxiliary blades 600a, 600b are added to cover the undesirable hole H. This adapted structure allows for space savings for storing the various vanes compared to the first embodiment, thus allowing for a more compact VA device 10.

[0060] Although the preferred embodiments of the present invention have been described above with reference to the accompanying drawings, 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 present invention, and these modifications and changes are also included in the scope of the present invention. [Explanation of symbols]

[0061] 1. Portable electronic devices and 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 recesses 220a, 220b cam groove 230a, 230b side edge 240a, 240b rear of blade 250a1, 250a2, 250b1, 250b2 fingers 300a, 300b auxiliary blades 310a, 310b recesses 320a, 320b cam groove 340a, 340b rear of blade 350a1, 350a2, 350b1, 350b2 fingers 360a, 360b side edge 400 Cover 410 Cover opening 420a, 420b cam groove 500 Actuator 510a Rotatable Arm (First Arm) 510b Rotatable arm (second arm) 511a, 511b boss 600a, 600b Secondary auxiliary blades 610a, 610b recesses 620a, 620b cam groove 630a,630b side edge 2000a, 2000b feathers 2100a, 2100b blades 5010a, 5010b arms 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' blade stroke S 1x Width component of arm stroke

Claims

1. A variable aperture device (10) for a camera module (1a), comprising: a base (100) having a base opening (110) and a pair of blade guides (120a, 120b) disposed on opposing longitudinal edges (130a, 130b) of the base (100) with the base opening (110) therebetween; a pair of main blades (200a, 200b) guided by the pair of blade guides (120a, 120b) of the base (100), the pair of main blades (200a, 200b) being slidably arranged with respect to the base (100) so as to approach and move away from each other, each of the main blades (200a, 200b) having a recess (210a, 210b), respectively, the recess (210a, 210b) being such that a central opening (A) is formed when the pair of main blades (200a, 200b) are closest to each other; １ ) together, and the pair of main blades (200a, 200b) define a fixed opening (A) when they are farthest apart from each other. ２ a pair of main blades (200a, 200b) that cooperate to define a a pair of auxiliary blades (300a, 300b) guided by the pair of blade guides (120a, 120b) of the base (100), the pair of auxiliary blades (300a, 300b) being slidably arranged with respect to the base (100) so as to approach and move away from each other, each of the auxiliary blades (300a, 300b) having a recess (310a, 310b), respectively, the recess (310a, 310b) being in contact with the central opening (A) when the pair of auxiliary blades (300a, 300b) are closest to each other; １ ) the smallest opening (A ３ ) when the pair of auxiliary blades (300a, 300b) are farthest from each other, the fixed opening (A ２ ) ４ a pair of auxiliary vanes (300a, 300b) that cooperate to define a The fixed opening (A ２ a cover (400) having a cover opening (410) substantially aligned with the base (100) and configured to restrain the pair of main blades (200a, 200b) and the pair of auxiliary blades (300a, 300b) in a 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 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, and when the pair of auxiliary blades (300a, 300b) are closest to each other, A variable aperture device (10).

2. The variable iris 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 have cam grooves (220a, 220b), the pair of auxiliary blades (300a, 300b) each have cam grooves (320a, 320b), and the bosses (511a, 511b) of the rotatable arms (510a, 510b) are connected to the cam grooves (220a, 220b) of the main blades (200a, 200b). and the cam grooves (320a, 320b) of the auxiliary blades (300a, 300b), and 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) of claim 3, wherein the pair of rotatable arms (510a, 510b) are rotatably supported on the base (100).

5. 5. The variable aperture device (10) of claim 3 or 4, 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 be able to enter the cam grooves (420a, 420b) of the cover (400).

6. The minimum opening (A) is formed by the recesses (310a, 310b) of the pair of auxiliary blades (300a, 300b). ３ 6. 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 pair of 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. The minimum opening (A) is formed by the recesses (310a, 310b) of the pair of auxiliary blades (300a, 300b). ３ 7. The variable aperture device (10) according to claim 1, wherein when the pair of auxiliary blades (300a, 300b) move to a closed position defined by the cooperation of the pair of rotatable arms (510a, 510b), the pair of rotatable arms (510a, 510b) are in a position substantially parallel to the direction of movement of the pair of auxiliary blades (300a, 300b).

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

9. 9. The variable iris device (10) according to claim 1, wherein when the pair of main blades (200a, 200b) and the pair of auxiliary blades (300a, 300b) move linearly, 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 blades (600a, 600b) guided by the pair of blade guides (120a, 120b) of the base (100), the pair of secondary auxiliary blades (600a, 600b) being slidably arranged with respect to the base (100) so as to move toward and away from each other, and each of the secondary auxiliary blades (600a, 600b) has a recess (610a, 610b), respectively, and the recess (610a, 610b) is configured to be in a position where the central opening (A) is ... １ ) the smallest opening (A ５ ) when the pair of secondary auxiliary vanes (600a, 600b) are farthest from each other, the fixed opening (A ２ ) that surrounds or substantially coincides with the maximum opening (A ６ 10. The variable iris device (10) according to claim 1, wherein the secondary auxiliary vanes (600a, 600b) are configured to protrude outward from the side edges (230a, 230b) of the main vanes (200a, 200b) 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) of claim 10 when dependent on claim 3, wherein the pair of secondary auxiliary blades (600a, 600b) have respective cam grooves (620a, 620b), the bosses (511a, 511b) of the rotatable arms (510a, 510b) are further configured to be received in the cam grooves (620a, 620b) of the secondary auxiliary blades (600a, 600b), and rotation of the rotatable arms (510a, 510b) is converted into linear motion of the secondary auxiliary blades (600a, 600b) by the cam grooves (620a, 620b) of the secondary auxiliary blades (600a, 600b).

12. 12. The variable iris device (10) according to claim 10 or 11, 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) is defined by the recesses (210a, 210b) of the pair of main blades (200a, 200b) in cooperation with each other. １ 13. The variable iris device (10) according to any one of claims 1 to 12, wherein the aperture is circular.

14. 14. A product (1) including a camera module (1a), said camera module (1a) comprising a variable aperture device (10) according to any one of claims 1 to 13.

15. The product (1) according to claim 14, wherein the product (1) is a device, an apparatus, an instrument, a machine, a facility, a tool, etc., comprising the camera module (1a).

16. 16. The product (1) according to claim 15, wherein the product (1) is a portable electronic device comprising the camera module (1a).

Images