JP2004198684A - Electronic equipment with built-in camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily incorporate a variable focus imaging optical system in electronic equipment at a low cost. <P>SOLUTION: First and second cam frames 26, 31 are arranged on both outsides of first and second lens holding frames 24, 25 and a spring 29 is arranged between the first and second lens holding frames 24, 25. The spring 29 energizes the first and second lens holding frames 24, 25 to directions which cause cam pins 33, 35 which are provided in the first and second lens holding frames 24, 25 to be respectively in contact with first and second cam surfaces 34, 36 which are provided in the first and second cam frames 26, 31. Ring-shaped permanent magnets 37, 38 are formed in circumferences of first and second lens holding frames 28, 30 and the frames 28, 30 rotate in synchronization by the attraction between the magnets 37, 38 and a magnet 39 provided in a rotating barrel 32 and move in accordance with the displacement of the first and second cam surfaces 34, 36. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a camera-equipped electronic device in which an electronic camera is built in an electronic device such as a mobile phone and a portable information terminal.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, there has been proposed a portable electronic device such as a mobile phone or a portable information terminal in which a small electronic camera is built in (Patent Document 1). The electronic camera includes a CCD or CMOS solid-state imaging device and an imaging optical system, and captures a subject image formed by the imaging optical system with the solid-state imaging device. The captured image can be checked on a liquid crystal monitor provided in the electronic device, and the captured image can be transmitted to another electronic device through a public line or the like. However, the imaging optical system is generally a pan-focus type using a single focus lens. Therefore, it is desired to incorporate an imaging optical system capable of changing the focal length.
[0003]
[Patent Document 1]
JP 2001-223924 A
[Problems to be solved by the invention]
However, in order to change the focal length, a mechanism for moving some of the taking lenses in the optical axis direction is required. 2. Description of the Related Art In a conventional photographic camera or the like, a cam barrel or the like is rotated by driving a motor, and a lens is moved to a predetermined position by displacement in the optical axis direction with respect to rotation of the cam. However, since the cylinder used for such a cam mechanism has a cam groove and a cam opening formed by injection molding using a plastic material, there is a problem that the production of the cylinder is not easy and the cost is high. In addition, accuracy is required, and the size of the cylinder is small in a photographing optical system used for a small electronic device, so that there is a problem that the operation becomes extremely difficult at the time of assembly.
[0005]
The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a low-cost electronic device that is devised so that a variable-focus imaging mechanism can be made compact and easily incorporated.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, in the camera-equipped electronic device according to claim 1, first and second lens holding members respectively holding at least two lens groups constituting a photographic lens, and the first and second lenses. A holding member for holding the holding member movably in the optical axis direction and rotatably in a rotational direction about the optical axis; and first and second cam pins provided on the first and second lens holding members, respectively. And first and second fixed cam members having first and second cam surfaces respectively contacting the first and second cam pins from the optical axis direction, and the first and second lens holding frames in synchronization with each other. And a synchronous rotating means for rotating.
[0007]
For example, when the focal length is changed by moving two adjacent lens groups, one urging means is provided between a pair of adjacent lens holding members, and a second urging means is provided on both outer sides of the pair of lens holding members. When the first and second cam members are disposed, and the first and second lens holding members are urged in opposite directions toward the first and second cam members by the urging means, respectively, the first and second lens members are urged. The second cam pin reliably contacts the first and second cam surfaces.
[0008]
As the synchronous rotating means, a rotating member which rotates in the circumferential direction around the optical axis by using the driving of a driving means such as a motor, and a transmitting means which synchronously transmits the rotation of the rotating member to the pair of lens holding members And As the transmitting means, a driving pin provided on the outer periphery of the first and second lens holding members may be directly rotated in association with the rotating member. Further, as another configuration, a pair of driven-side magnets provided on the first and second lens holding members, and a driven-side magnet provided on the rotating member and having magnetic poles attracting each of the driven-side magnets. May be.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
As shown in FIGS. 1 and 2, the mobile phone 10 includes a main body 11 and a folding part 12, and the folding part 12 can be raised and lowered with respect to the main body 11. The main unit 11 is provided with an operation unit 13, a shutter button 14, a zoom button 15, and the like. The operation unit 13 includes a large number of operation buttons for performing telephone and mail operations. The zoom button 15 is composed of two buttons for zooming to the tele end or the wide end. The zoom button 15 and the shutter button 14 are provided on the side surface of the main body 11 and can be operated even when the camera is lying down. On the back surface of the folding unit 12, a liquid crystal display unit 16 for displaying a captured image is provided. An imaging window 17 is provided on the surface of the folded portion exposed when the camera is lying down, and a camera unit is arranged behind the imaging window 17.
[0010]
The camera unit includes an imaging optical system 20 and a solid-state imaging device 21 as shown in FIG. The imaging optical system 20 includes first and second lens groups 22 and 23 that constitute a photographic lens, and continuously changes the focal length between the tele position and the wide position by changing the distance between each other. It is a zoom type optical system that can be used.
[0011]
The first and second lens groups 22 and 23 are held by first and second lens holding frames 24 and 25, respectively. The imaging optical system 20 is held by a lens barrel, and the lens barrel includes a first cam frame 26, a fixed cylinder 27, a first lens holding frame 28, a coil spring 29, a second lens holding frame 30, as shown in FIG. It comprises a second cam frame 31 and a rotary cylinder 32.
[0012]
The first and second lens holding frames 28 and 30 are incorporated in the inner surface of the fixed barrel 27 so as to be rotatable in the circumferential direction around the optical axis and movable in the optical axis direction.
[0013]
The first lens holding frame 28, the coil spring 29, and the second lens holding frame 30 are sequentially inserted into the inner surface of the fixed barrel 27. The first cam frame 26 is fixed to the front end of the fixed cylinder 27 in a state where rotation is stopped, and the second cam frame 31 is fitted and fixed to the rear end of the fixed cylinder 27 in a state where rotation is stopped. The coil spring 29 is disposed between the first lens holding frame 28 and the second lens holding frame 30 and urges the first and second lens holding frames 28 and 30 in directions away from each other. The coil spring 29 is a compression coil spring formed with an inner diameter that does not block the optical path of the subject.
[0014]
At the front end of the first lens holding frame 28, a cam pin 33 protruding forward in the optical axis direction is provided. The cam pin 33 comes into contact with a cam surface 34 provided at a rear end of the first cam frame 26. A cam pin 35 projecting rearward in the optical axis direction is also provided at the rear end of the second lens holding frame 30. The cam pin 35 contacts a cam surface 36 provided at the front end of the second cam frame 31. These cam surfaces 34 and 36 move the first and second lens holding frames 28 and 30 in the optical axis direction along a predetermined magnification locus. Note that three cam pins 33 and 35 and three cam surfaces 34 and 36 are provided at three divided positions in the rotation direction about the optical axis. The cam pins 33 and 35 may have any shape as long as they come into contact with the cam surface.
[0015]
First and second driven magnets 37 and 38 are attached to the outer periphery of the first and second lens holding frames 28 and 30, respectively. The first and second driven magnets 37 and 38 are ring-shaped permanent magnets having S poles on the outside and N poles on the inside so that the directions of the magnetic poles are the same.
[0016]
A rotating cylinder 32 is rotatably arranged on the outer periphery of the fixed cylinder 27. A driving magnet 39 is fitted on the inner periphery of the rotary cylinder 32. The driving magnet 39 is a ring-shaped permanent magnet having an S pole on the outside and an N pole on the inside so as to be magnetic poles for attracting the first and second driven magnets 37 and 38, respectively. The length is a length covering the first and second driven magnets 37 and 38. If the structure is such that the magnets can be rotated synchronously using the magnetism of the permanent magnet, for example, the first and second driven members having an N pole on the outside and an S pole on the inside so that the arrangement of the magnetic poles are different. It may be composed of magnets 37 and 38 and a driving magnet 39 having N poles on the outside and S poles on the inside, and two ring magnets having the same number of poles for both the driving and driven ring-shaped permanent magnets. A divided or multi-divided one may be used.
[0017]
A gear tooth row 40 is formed on the outer periphery of the rear end of the rotary cylinder 32. The drive of the motor 42 is transmitted to the gear train 40 via a gear train 41 for reduction. When the rotating cylinder 32 rotates, the driving magnets 37 and 38 attract the driven magnets 39, and the first and second lens holding frames 28 and 30 rotate in synchronization with each other. Note that, in order to ensure synchronization between the first and second lens holding frames 28 and 30, an engagement means that engages with the first and second lens holding frames 28 and 30 in the rotation direction may be provided. good.
[0018]
The control unit 43 controls each unit of the mobile phone 10 in a comprehensive manner, and controls the driving of the motor 42 via the driver 44 in accordance with the operation of the zoom button 15.
[0019]
The solid-state imaging device 21 is attached to a substrate 46 provided inside the folding section 12. The substrate 46 is attached to the rear end of the fixed barrel 27 via the holding member 47 such that the image plane of the imaging optical system 20 matches the imaging plane of the solid-state imaging device 21.
[0020]
In this embodiment, three cam surfaces 34 and 36 having the same displacement are provided at three divided positions around the optical axis, and three cam pins 33 and 35 are provided so as to abut on the respective cam surfaces 34 and 36. Provided. Therefore, the amount of rotation of the motor 42 is controlled so that the first and second lens holding frames 28 and 30 rotate within an angle of 120 degrees during zooming.
[0021]
The operation of the above configuration will be briefly described. The initial state of the imaging optical system 20 is a wide position where the first and second lens holding frames 28 and 30 approach each other.
[0022]
When photographing, the user operates the operation unit 13 to set the mobile phone 10 in the camera mode. As a result, the image of the subject image formed by the imaging optical system 20 by driving the solid-state imaging device 21 is displayed on the liquid crystal display unit 16. When the shutter button 14 is pressed after framing the surface of the folding section 12 toward the subject in this mode, the subject image captured at that time is stored in the memory. The imaging optical system 20 has a pan focus in which the foreground to the background are clearly focused.
[0023]
When zooming the imaging optical system 20 from the wide position to the tele position, the zoom button 15 is operated. In response to this operation, the control means 43 drives the motor 42 via the driver 44. The drive of the motor 42 is transmitted to the rotating cylinder 32 via the gear train 41, and the rotating cylinder 32 rotates with respect to the fixed cylinder 27. When the rotary cylinder 32 rotates, the driving magnets 37 and 38 attract the driven magnets 39 and the first and second lens holding frames 28 and 30 rotate relative to the first and second cam frames 26 and 31. . When the first and second lens holding frames 28, 30 rotate, the cam pins 33, 35 slide on the cam surfaces 34, 36. Accordingly, the first and second lens holding frames 28 and 30 move in the optical axis direction according to the displacement of the cam surfaces 34 and 36 in the optical axis direction with respect to the rotation amount. At this time, since the rotations of the first and second lens holding frames 28 and 30 are synchronized with each other, the first and second lens holding frames 28 and 30 can be respectively moved along a predetermined magnification locus. . Thereby, the focal length of the photographing optical system 20 is changed.
[0024]
In the above-described embodiment, as the synchronous rotation means, the first and second lens holding frames 28 and 30 are configured to rotate in synchronization with each other using the inquiries of the permanent magnets 37 to 39. Instead, the magnets 37 to 39 are omitted and drive pins 50 and 51 are provided on the first and second lens holding frames 28 and 30, respectively, as shown in FIG. Alternatively, the rotation of the rotary barrel 32 may be directly transmitted to the first and second lens holding frames 28 and 30 by linking the rotation to the first and second lens holding frames 28 and 30. In this case, a pair of insertion openings 52, 53 for inserting the drive pins 50, 51 into the fixed cylinder 27, and the rotating cylinder 32 for driving to transmit its own rotation to the drive pins 50, 51. Grooves or openings 54, 55 need to be provided.
[0025]
Each of the insertion openings 52 and 53 has a length along the optical axis direction that exceeds the moving length of the first and second lens holding frames 28 and 30 in the optical axis direction, and has a first length in the circumferential direction. In addition, the second lens holding frames 28 and 30 need to be formed with a length exceeding the length corresponding to the maximum rotation amount. The driving grooves or openings 54 and 55 have a width in the circumferential direction sandwiching the driving pins 50 and 51 and a length along the optical axis direction in the optical axis direction of the first and second lens holding frames 28 and 30. Make with a length that exceeds the maximum travel length of The insertion openings 52, 53 and the driving grooves or openings 54, 55 may be connected to each other to form one.
[0026]
In the above embodiment, the photographing optical system is constituted by the two adjacent lens groups 22 and 23. However, the present invention is not limited to this, and is constituted by three or more lens groups, of which at least two lens groups are included. It goes without saying that the present invention can also be applied to a photographing optical system in which the focal length can be changed by changing the interval.
[0027]
Further, in the above embodiment, the camera using the present invention is built in the mobile phone, but may be built in an electronic device such as a PDA (Personal Digital (Data) Assistants) (portable information terminal).
[0028]
【The invention's effect】
As described above, in the present invention, the fixed first and second cam members having the first and second cam surfaces that come into contact with the cam pins provided on the first and second lens holding members from the optical axis direction are provided. By rotating the first and second lens holding members synchronously, the first and second lens holding frames are moved in the optical axis direction according to the displacement of the first and second cam surfaces, respectively, so that the focal length is continuous. Since it is configured so as to be changed in terms of size, it is easier to manufacture and assemble and can be manufactured at low cost as compared with a cylinder having a cam surface on the outer periphery as described in the related art.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a mobile phone using the present invention, showing a lying state.
FIG. 2 is a perspective view showing the mobile phone in an upright state.
FIG. 3 is a cross-sectional view showing a lens barrel incorporated in a mobile phone.
FIG. 4 is an exploded perspective view showing an imaging optical system.
FIG. 5 is a sectional view showing another embodiment in which first and second lens holding frames are directly and synchronously rotated by a driving pin.
[Explanation of symbols]
Reference Signs List 10 mobile phone 21 solid-state imaging device 22 first lens 23 second lens 27 fixed barrel 28 first lens holding frame 29 coil spring 30 second lens holding frame 32 rotating barrel 33, 35 cam pins 34, 36 cam surface 50, 51 drive pin

Claims (3)

In a camera-equipped electronic device incorporating a variable-focus imaging optical system that changes a focal length by moving at least two lens groups of the imaging lens so that the distance between them is different,
First and second lens holding members for holding the lens groups, respectively, and the first and second lens holding members are held movably in the optical axis direction and rotatable in a rotation direction about the optical axis. A holding member, first and second cam pins provided on the first and second lens holding members, respectively, and first and second cam surfaces respectively contacting the first and second cam pins from the optical axis direction. An electronic device with a camera, comprising: fixed first and second cam members; and synchronous rotation means for synchronously rotating the first and second lens holding frames. The first and second lens holding frames are urged in the optical axis direction by urging means, and the cam pins abut against cam surfaces arranged in the urging direction of the urging means. Item 2. An electronic device with a camera according to Item 1. The synchronous rotating means includes: a pair of driven magnets provided on the first and second lens holding members; a driving magnet having magnetic poles attracting the pair of driven magnets; and a driving magnet. The camera-equipped electronic device according to claim 1, further comprising a rotating unit configured to rotate the electronic device.

Images