JP2005084605A - Imaging apparatus and personal digital assistant with the apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an imaging apparatus which has a shutter for intercepting light from a subject at the time of finishing exposure or reading image data, saves space, and has reduced total thickness including an armoring member disposed in front of the imaging apparatus. <P>SOLUTION: The imaging apparatus includes: a taking lens; the armoring member having an opening opposite the taking lens; and a shutter disposed between the taking lens and the armoring member. In the imaging apparatus, the operating parts of shutter vanes have curved faces. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an imaging apparatus, and more particularly to a small and thin imaging apparatus mounted on a portable terminal such as a mobile phone or a mobile computer.

  Conventionally, small and thin imaging devices have been mounted on small and thin portable terminals such as mobile phones and PDAs (Personal Digital Assistants), which allows not only audio information but also image information to a remote location. It is possible to transmit to each other.

  As an image pickup element used in these image pickup apparatuses, a solid-state image pickup element such as a charge coupled device (CCD) type image sensor or a complementary metal-oxide semiconductor (CMOS) type image sensor is used. In general, the front surface of the lens is provided with a dust-proof cover glass.

On the other hand, an ordinary digital camera or the like generally has a lens barrier disposed on the front surface of a photographing lens. Among these, a front aperture type photographic lens is used, and the turret type diaphragm mechanism arranged between the photographic lens and the exterior cover is used to switch the aperture value and also serve as a lens cover, thereby reducing costs. A camera is known (see, for example, Patent Document 1).
JP 2001-13542 A

  The dust-proof cover glass frequently used in the above-described imaging devices used for portable terminals such as mobile phones is easily stained due to fingerprints, dust adhesion, etc., and is equipped with an imaging device with a high pixel count that is increasing in recent years. When used in an imaging apparatus, there is a problem in that the high image quality is hindered by dirt, and sufficient image quality cannot be obtained.

  When an image sensor with a large number of pixels is mounted, it is desirable to shield the image sensor with a shutter when reading image data after shooting, regardless of whether the image sensor is an all-pixel readout method or an interlace readout method.

  On the other hand, when a method such as the above-mentioned patent document in which a light-blocking member such as a diaphragm or a lens cover is disposed between a front aperture type photographing lens and an exterior member is applied to an imaging apparatus used for a portable terminal, the following is performed. There is a problem.

  FIG. 6 is a cross-sectional view when a conventional shutter is applied to an imaging device used in a mobile terminal.

  In the figure, reference numeral 50 denotes an image pickup apparatus, which includes a taking lens, an image pickup element, and a lens barrel 3 for holding them. Reference numeral 2 denotes a lens, which is a lens located closest to the object side among the photographing lenses. A shutter 4 is disposed in front of the lens 2, and an exterior member 5 is further disposed. As can be seen from the drawing, the thickness d of the shutter 4 and the thickness t of the exterior member 5 are required in front of the lens 2. In recent years, portable terminals are required to further reduce space and thickness, and not only to reduce the size of the imaging apparatus but also to reduce the total thickness S including the thickness up to the exterior member. .

  In view of the above problems, the present invention has a shutter that shields subject light at the end of exposure or when reading out image data, and has a total thickness including a space-saving exterior member disposed on the front surface of the imaging apparatus. It is an object of the present invention to obtain an imaging device with a small thickness.

  Said subject is solved by the following structures.

  1) In an imaging device having a photographic lens, an exterior member having an opening facing the photographic lens, and a shutter disposed between the photographic lens and the exterior member, an operating region of a shutter blade of the shutter is An imaging device characterized by being formed on a curved surface.

  2) The imaging device according to 1), wherein when the shutter blade is closed, at least a part of the shutter blade enters the thickness of the exterior member.

  3) The imaging device according to 1) or 2), wherein the shutter blade is formed in a curved surface.

  4) The imaging device according to any one of 1) to 3), wherein the shutter blade has a dome shape.

  5) The imaging device according to any one of 1) to 4), wherein the shutter blades are composed of a plurality of sheets.

  6) The imaging device according to any one of 1) to 5), wherein the shutter blade also serves as a lens cover.

  7) A portable terminal including the imaging device according to any one of 1) to 6).

  According to the present invention, the volume necessary for shutter operation can be reduced by making the shutter operation region a curved surface, and an imaging apparatus that achieves space saving can be obtained.

  Further, when the shutter blades are in a closed state, by arranging at least a part of the shutter blades so as to enter the thickness of the exterior member, the total thickness including the exterior member disposed on the front surface of the imaging device is increased. A thin imaging device can be obtained.

  Furthermore, it is preferable that the shutter blade has a curved surface, for example, a dome shape formed of a part of a spherical surface, or a dome shape in which a cylindrical shape and a spherical surface are connected. An imaging apparatus having the smallest thickness can be obtained.

  In addition, it is preferable that the shutter blades are composed of a plurality of sheets, and the shutter operating space can be further reduced, and efficient use of the space inside the portable terminal becomes possible.

  Further, since the shutter blade also serves as the lens cover, the cost can be reduced.

  Furthermore, by setting it as the portable terminal provided with said imaging device, the portable terminal which has said effect can be obtained.

  Hereinafter, the present invention will be described in detail with reference to embodiments, but the present invention is not limited thereto.

  FIG. 1 is a diagram showing an example of a portable terminal equipped with the imaging apparatus of the present invention. As shown in the figure, the mobile terminal is, for example, a foldable mobile phone T (hereinafter referred to as a mobile phone T), and includes a top casing 71 as a case with a display screen D and a bottom with an operation button P. The casing 72 is connected via a hinge 73. The imaging device 100 is built below the display screen D in the upper housing 71, and is arranged so that the imaging device 100 can capture subject light from the outer surface side of the upper housing 71.

  Note that the portable terminal does not have to be foldable, and the position of the imaging device is not limited to this.

  FIG. 2 is a schematic cross-sectional view of the imaging apparatus 100 of the present invention cut along the line FF shown in FIG. FIG. 4A shows a state where the shutter is closed, and FIG. 4B shows a state where the shutter is opened.

  In FIG. 1A, an imaging apparatus 100 includes a photographic lens having a first lens 2, a second lens 6, and a third lens 7 from the object side and having an optical axis of O, and a mirror that holds the photographic lens. The body 3 includes an image pickup device 8, a printed circuit board 9 on which the image pickup device 8 is mounted, and shutter blades 4m and 4n. Reference numeral 5 denotes an exterior member. The above-described CMOS type or CCD type image sensor is used for the image sensor 8.

  As illustrated, the shutter blades 4 m and 4 n are disposed between the first lens 2 and the exterior member 5. In addition, the shutter blades 4m and 4n are composed of two in this example, and are formed in curved surfaces that approximate the light incident surface side of the first lens 2, respectively. In this example, the shape is divided into two dome shapes.

  The surface of the exterior member 5 facing the shutter blade 4 is arranged so that at least a part of the shutter blades 4m and 4n enters the thickness of the exterior member 5 when the shutter blade is closed. It has been enthralled by. A region where a photographing light beam indicated by a broken line is incident is an opening.

  When the image pickup apparatus 100 is not used, the opening portion closes the shutter blades 4m and 4n and functions as a lens cover as shown in FIG. By doing so, it is possible to prevent the finger and the like from being soiled and to reduce the cost.

  On the other hand, when used for photographing, opening / closing control is performed so as to function as a shutter according to an open state as shown in FIG. 5B and a closed state as shown in FIG.

  That is, in the imaging device of the present invention, by making the operating region of the shutter blades curved, it is possible to use the dead space around the first lens in the operating region of the shutter blades conventionally required in a plane, The occupied volume of the imaging device can be reduced, and space can be saved. Moreover, this effect can be enjoyed to the maximum when the shutter blades are formed in a curved surface.

  The operating region of the shutter blades is a region where the shutter blades 4m and 4n are operated by opening and closing the shutter as shown in FIGS. 4A and 4B, that is, the shape of the space in which the shutter blades move. That is.

  Further, when the shutter blades are closed, at least a part of the shutter blades is disposed so as to enter the thickness of the exterior member, so that the exterior member disposed on the front surface of the imaging device in addition to the space saving described above. It is possible to obtain an imaging device with a reduced total thickness including the above.

  Furthermore, as shown in FIG. 2A, when the shutter blades are in the closed state, it is most preferable that at least a part of the shutter blades and a part of the photographing lens are placed within the thickness of the exterior member. Desirably, it is possible to obtain an imaging device having a minimum total thickness including the exterior member disposed on the front surface of the imaging device.

  FIG. 3 is a perspective view of the imaging apparatus 100 of the present invention. In the following drawings, the same functional members are given the same reference numerals in order to avoid repeated description.

  As shown in the figure, on the outside of the image pickup apparatus 100 of the present invention, shutter blades 4n and 4m, a blade drive plate 17, a drive gear 18 for driving the blade drive plate 17, and a drive motor 20 are arranged. . The drive motor 20 is preferably a stepping motor, but may be a DC motor or the like. The drive motor 20 is electrically connected to the printed circuit board 9 and driven.

  In the drawing, two shutter blades 4n and 4m are pivotally fixed to support shafts 11 and 12 formed on the lens barrel 3, respectively. A spring 13 is hung on the shutter blade 4 n and urges the shutter blade 4 n to the support shaft 11 in the clockwise direction in the figure. The shutter blade 4n contacts the stopper pin 14 when the shutter is closed. Furthermore, a pin 15 is implanted in the shutter blade 4n and is engaged by a bifurcated portion 16 of the shutter blade 4m. By engaging the pin 15 and the bifurcated portion 16, the shutter blade 4m is configured to rotate in the opposite direction following the rotation of the shutter blade 4n.

  The blade drive plate 17 has a guide groove 17m formed in a direction orthogonal to the optical axis O, and two guide pins 19 formed in the lens barrel 3 are engaged with the guide groove 17m. . Further, the blade drive plate 17 has a gear portion 17 g and meshes with the drive gear 18. As a result, the blade drive plate 17 is movable in a direction orthogonal to the optical axis O (in the direction of the arrow in the drawing) with the rotation of the drive gear 18 provided continuously with the drive motor 20.

  The opening / closing operation of the shutter blades of the imaging apparatus 100 configured as described above will be described below.

  FIG. 4 is a view showing a shutter blade opening / closing mechanism of the imaging apparatus 100 of the present invention shown in FIG. This figure shows only the shutter blade opening / closing mechanism shown in FIG. FIG. 4A shows the closed state of the shutter blades, and FIG. 4B shows the open state of the shutter blades.

  In the closed state of the shutter blades 4m and 4n shown in FIG. 5A, the shutter blade 4n abuts against the stopper pin 14 by the biasing force of the spring 13, and the shutter blade 4m is also engaged by the engagement of the pin 15 and the bifurcated portion 16. The closed state is shown.

  From this state, when the drive motor 20 is driven, the drive gear 18 is rotated (see FIG. 3), and the meshing blade drive plate 17 is moved in the direction of the arrow in the figure, the inclined surface 17k formed on the blade drive plate 17 is When the blade driving plate 17 is further moved by coming into contact with the protrusion 4t of the shutter blade 4n, the protrusion 4t is rotated along the inclined surface 17k while resisting the biasing force of the spring 13. Accordingly, the shutter blade 4m rotates in the opposite direction to the shutter blade 4m in accordance with the rotation of the pin 15 implanted in the shutter blade 4n. As a result, the shutter is opened as shown in FIG.

  In order to change from the open state of FIG. 5B to the closed state of FIG. 4A, the drive motor is reversely rotated, and the blade drive plate 17 is moved in the reverse direction, so that the blade drive plate 17 is formed. The inclined surface 17k is disengaged from the protrusion 4t of the shutter blade 4n, and can be returned to the closed state by the biasing force of the spring 13.

  A schematic operation when the imaging apparatus configured as described above is mounted on a portable terminal will be described.

  FIG. 5 is a flowchart of an outline of the operation when the camera mode is set among the functions of the mobile terminal.

  In the flowchart, first, it is determined whether or not the camera mode is set (S101), and when it is determined that the camera mode is set, the shutter is opened (S102), that is, the shutter is closed in a mode other than the camera mode. It has the same function as a barrier. The mechanical operation for opening the shutter is as described with reference to FIG.

  Next, the imaging device is turned on, a through image is displayed on the display screen D (see FIG. 1), and exposure conditions at the time of shooting are determined in advance (S103). Thereafter, it is determined whether or not the camera mode is set again (S104). If the camera mode is canceled, the process returns to S101. If the camera mode is selected, the process proceeds to the next, and a button (for example, provided with a release function). It waits for any of the operation buttons P shown in FIG. 1 to be turned on (S105). When a button having a release function is turned on, the charge in the image sensor is cleared, and then charge accumulation for photographing is started (S106), and charge accumulation is performed until the exposure time predetermined in S103 is reached. Perform (S107).

  When the exposure time predetermined in S107 is reached, the shutter is closed (S108). The mechanical operation for closing the shutter is as described in FIG. As a result, the subject light flux for photographing to the image sensor is blocked.

  Thereafter, as is well known, the charge stored in the image sensor, that is, the image signal is read (S109), the image signal is A / D converted (S110), and the data after the A / D conversion is subjected to image processing. Thereafter, the image data is compressed (S111). Next, the compressed image data is stored in the recording memory (S112). This completes the shooting of one image.

  Thereafter, the process returns to S101 to confirm again whether the camera mode is selected. If the camera mode is selected, the process proceeds to S102. If the camera mode is canceled, the process proceeds to S121, and the camera mode end operation is performed. In S121 and S101, the end operation of S121 includes a shutter closing operation. In S112 and S101, the shutter is already closed, so that the closing operation is unnecessary. is there. After this end operation, the process proceeds to another predetermined mode (S122).

  The above is the outline of the operation when the mobile terminal equipped with the imaging apparatus of the present invention is set to the camera mode.

  Note that the opening / closing direction of the shutter blades is desirably set to open / close in the short side direction of the image sensor. By doing so, the shutter blade operating region can be reduced, but the present invention is not limited to this.

  The shutter blade is most preferably a curved surface approximating the first surface of the image pickup optical system, that is, a spherical dome shape. However, the shutter blade is not limited to this, but is not limited to this, and has a cylindrical shape or other cylindrical shape and spherical shape. It may be a connected dome shape or the like.

  In addition, in the case of the present invention, in addition to the decrease in the peripheral light amount of a known imaging optical system, the light amount unevenness due to a slight deviation between the entrance pupil surface and the shutter surface and the thickness when a plurality of shutter blades are configured. Shading may occur due to misaligned orientation. In such a case, in the image processing performed in S111, a light amount correction table or the like that uses the exposure time and the position of each point on the imaging surface as factors is prepared in advance, and image data is obtained based on the light amount correction table. By correcting, the above unevenness and shading can be eliminated.

It is the figure which showed an example of the portable terminal carrying the imaging device of this invention. It is a schematic sectional drawing of the imaging device 100 of this invention cut | disconnected by the FF line shown in FIG. It is a perspective view of the imaging device 100 of this invention. It is a figure which shows the opening-and-closing mechanism of the shutter blade | wing of the imaging device 100 of this invention shown in FIG. It is a flowchart of the operation | movement outline when it sets to camera mode among the functions of a portable terminal. It is sectional drawing at the time of applying the conventional shutter to the imaging device used for a portable terminal.

Explanation of symbols

2 First lens 3 Lens barrel 4 m Shutter blade 4n Shutter blade 5 Exterior member 6 Second lens 7 Third lens 8 Image sensor 9 Printed circuit board 13 Spring 17 Blade drive plate 18 Drive gear 20 Drive motor

Claims (7)

In an imaging device having a photographic lens, an exterior member having an opening facing the photographic lens, and a shutter disposed between the photographic lens and the exterior member,
An image pickup apparatus, wherein an operating area of a shutter blade of the shutter is formed in a curved surface. The imaging apparatus according to claim 1, wherein when the shutter blade is in a closed state, at least a part of the shutter blade is disposed so as to enter a thickness of the exterior member. The imaging apparatus according to claim 1, wherein the shutter blade is formed in a curved surface. The imaging apparatus according to claim 1, wherein the shutter blade has a dome shape. The imaging apparatus according to claim 1, wherein the shutter blade is configured by a plurality of sheets. The imaging device according to claim 1, wherein the shutter blade also serves as a lens cover. A portable terminal comprising the imaging device according to claim 1.

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