JP2009169079A - Camera with built-in projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent shading of a projected image without increasing costs or camera size or impairing camera stability. <P>SOLUTION: A projection window is provided on a side face of a camera, so that when a camera body 100 is supported by a portion of the camera body 100 and a portion of a photographic lens barrel 1, an optical projection axis X can be pointed diagonally upwards to control shading of a projected image. If shading still occurs, the lens barrel 1 is extended to further increase a projection angle to prevent shading. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a digital camera with a built-in projector.

  This type of camera with a built-in projector can project image data shot in the shooting mode to the outside by setting the projection mode (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 2002-369050

  In the projector built-in camera, considering that the projection is performed with the camera placed on the desk or floor, the projection window is set as high as possible so that part of the image is not vignetted on the placement surface. Therefore, it is necessary to consider that the image is projected at an angle upward rather than horizontally. However, when the projection distance becomes long, vignetting may occur despite this kind of consideration, and in this case, it is necessary to increase the projection angle. If the camera can be supported on the mounting surface in an oblique state, the projection angle can be increased. However, this is extremely difficult, and if the camera is projected by hand, the image is not stable. Thus, a configuration that can change the projection angle without impairing stability is desired, but has not yet been realized.

The camera with a built-in projector according to the present invention has a photographing lens barrel that extends and contracts with respect to the camera body, and when a part of the camera body and a part of the photographing lens barrel are brought into contact with the mounting surface And a projector unit that changes an image projection angle in accordance with a change in posture of the camera body due to expansion and contraction of the lens barrel.
Correction means for performing processing for correcting distortion of the projected image that may occur according to the projection angle based on the expansion and contraction state of the photographic lens barrel may be provided.
A camera with a built-in projector according to another aspect of the present invention provides an image according to a change in the height of the camera body due to expansion and contraction of the photographic lens barrel when the photographic lens barrel and the photographic lens barrel are brought into contact with the mounting surface. And a projector unit in which the height of the projection optical axis changes.
Projector unit so that the vertical direction of the projected image matches the vertical direction of the original image when projection is performed with a part of the camera body and a part of the taking lens barrel in contact with the mounting surface. May be determined.
The photographic lens barrel may be a zoom lens barrel that changes the photographic angle of view by the expansion and contraction.
In the telescopic movable range of the photographic lens barrel, at least two projection expansion / contraction states may be determined in advance, and any one of the projection expansion / contraction states may be selected by an operation. In this case, a mechanism for preventing the photographic lens barrel from contracting due to the weight load of the camera body in each projecting expansion / contraction state may be provided in the telescopic driving mechanism of the photographic lens barrel.
A plane portion for ensuring the stability of the camera may be formed at a position that contacts the mounting surface of the photographing lens barrel.

  According to the present invention, the expansion and contraction of the photographic lens barrel can be used to change the projection angle, so that the image vignetting is not accompanied by an increase in cost and an increase in the size of the camera, and without impairing the stability of the camera. Can be prevented.

An embodiment of the present invention will be described with reference to FIGS.
1 and 2 are perspective views of the projector built-in digital camera according to the present embodiment. A photographing lens barrel 1 is provided on the front surface of the camera body 100, a release button 2 is provided on the upper surface, and a projection window 3 of the projector is provided on the right side surface. On the back of the camera body 100, a liquid crystal monitor 4 capable of displaying an image, a zoom button 5, and various other operation members 6 are provided.

  The lens barrel 1 includes a first cylinder 1A that expands and contracts with respect to the camera body 100, and a second cylinder 1B that expands and contracts with respect to the first cylinder 1A. 1B holds an optical system. Then, zooming is performed by expansion and contraction (feeding / retracting) of the cylinders 1A and 1B, and the shooting angle of view is changed. When the power switch of the camera is turned off, the cylinders 1A and 1B are fully retracted into the main body 100 (collapsed state), and when the power switch is turned on, they are extended to the wide-angle end position. After that, shooting is allowed. The wide-angle end position is a position where the total extension amount of the lens barrel 1 is the smallest while photographing is allowed. Thereafter, the lens barrel is driven between the wide-angle end position and the telephoto end position in accordance with the operation of the zoom button 5. Note that the position where the total amount of feeding is the largest is not always the telephoto end position.

  In the camera body 100, a projector module 30 is built in one end side (here, the right end side). As shown in the sectional view of FIG. 3, the projector module 30 includes a light source 31 such as a high-intensity LED, a condenser lens 32, a polarization beam splitter (hereinafter referred to as PBS) 33, and a reflective liquid crystal panel 34 such as LCOS. The projection lens 35, the mirror 36, a case 37 for housing them, and a metal heat dissipation block 38 integrated with the light source 31. A configuration using a transmissive liquid crystal panel 34 may also be used.

  FIG. 4 shows a camera control system. The camera operation unit 21 performs basic operations as a digital camera, such as imaging, image processing, image recording, and image reproduction (in shooting mode and reproduction mode). The projector driving unit 22 controls the light source 31 and the liquid crystal panel 34 of the projector module 30 and projects image data recorded on a recording medium (not shown) to the outside (in the projection mode). The lens barrel drive unit 23 drives the lens barrel 1 (first and second cylinders 1A and 1B) to extend and contract by a zoom motor 24. The switches 25 are composed of switches that are turned on / off by the operation of the release button 2, the zoom button 5, the operation member 6, and the like. Based on the on / off signal of the switches 25, the CPU 26 controls each of the above parts to perform various operations.

Next, the operation in the projection mode will be described in detail.
In the projection mode, desired image data recorded on the recording medium can be projected to the outside using the projector module 30 described above. The CPU 26 sends the image data to the liquid crystal panel 34 via the projector driving unit 22 and displays it. When the light source 31 is turned on in this state, the light source light passes through the condenser lens 32 and the PBS 33 and enters the reflective liquid crystal panel 34, and the reflected light image is bent 90 degrees by the PBS 33. The bent light passes through the projection lens 35, is bent again by the mirror 36, and is projected to the right side of the camera through the projection window 3. According to this, an image can be projected on a wall or the like and viewed by a plurality of people. The size of the projected image increases as the projection distance increases.

  In this embodiment, as shown in FIG. 5, the projection is performed with the camera facing downward. Therefore, the orientation of the liquid crystal panel 34 and the like is determined so that the image projected in this state has an appropriate rotation angle. An appropriate rotation angle is an angle at which the top and bottom direction of an image taken at a normal lateral position matches the top and bottom direction of a projected image. Incidentally, when projection is performed with the camera standing as shown in FIG. 1, the projected image does not have an appropriate rotation angle.

  FIG. 2 and FIG. 5A show a state where the camera is faced down and placed on a horizontal surface (desk surface or floor surface). Since the lens barrel 1 is in the retracted position, the front surface of the camera body 100 is in surface contact with the mounting surface, and the projection optical axis X is in the horizontal direction. At this time, the power switch of the camera is turned off. However, if projection is performed in this posture, the lower part of the image is vignetted on the placement surface, and a complete projection image cannot be formed.

  When the power switch is turned on, as shown in FIG. 5B, the lens barrel 1 is automatically extended to the wide-angle end position, and the camera main body 100 is raised with the left end corner as a fulcrum accordingly. As can be seen from the figure, since the lens barrel 1 is provided to the right of the center of the camera body 100, the left end is always raised as a fulcrum from the point of weight balance, and the projection optical axis X is obliquely upward accordingly. Direction. Therefore, vignetting in the lower part of the image can be suppressed to some extent.

  However, if the projection distance is increased in order to enlarge the projected image, vignetting may occur even at the projection angle in FIG. In this case, the possibility that vignetting can be prevented increases by further extending the lens barrel 1 and increasing the projection angle as shown in FIG. The lens barrel 1 can be extended / retracted by operating the zoom button 5 in the same manner as normal zooming.

FIG. 7 shows an example of control when the zoom button is operated.
In step S1, the camera mode is determined. If it is a photographing mode, a normal zoom up or down operation is performed in steps S2 to S5. In either case, the zoom motor 24 is driven at a normal speed. It goes without saying that the motor 24 is stopped when the zoom limit is reached.

  When the camera mode is the projection mode, lens barrel driving for changing the projection angle (an angle formed by the projection optical axis X and the horizontal plane) is performed in steps S6 to S8. The figure shows an example in which two projection angles can be selected. The lens barrel 1 is driven to the maximum extended position by the tele side operation of the zoom button 5, and is driven to the wide angle end position by the wide side operation. In either case, one-touch operation is sufficient, and there is no need to keep pressing the zoom button 5. Further, when driving to the maximum extension position, the zoom motor 24 is driven at a lower speed than the normal speed.

  The reason why the zoom motor 2 is driven at a low speed in the projection mode is that the lens barrel extension in the camera posture of FIG. 5 acts as a load due to the weight of the camera body 100, and therefore there is a possibility that the torque will be insufficient at a normal speed. . If it is assumed that the lens barrel drive is always performed by holding the camera by hand (specify that in the instruction manual), it is not necessary to drive at a low speed.

  In FIG. 7, when the camera mode is the playback mode, processing such as increasing or decreasing the number of thumbnail images to be displayed or enlarging / reducing the display image is performed instead of driving the lens barrel.

  Here, since the projection plane is assumed to be a vertical plane, in the above projection method, the projection optical axis X is not orthogonal to the projection plane, and the projection image is distorted into a trapezoid as it is. In order to correct this type of distortion, so-called trapezoidal correction, in which the image displayed on the liquid crystal panel 34 is deformed according to the projection angle, may be performed. Since the projection angle is uniquely determined by the lens barrel 1 feed amount, for example, a table in which the feed amount and the trapezoidal correction amount are associated with each other is stored in the camera in advance, and the CPU 26 corrects the correction amount according to the lens barrel feed amount. Is read out from the table, and the display image is corrected based on the table, whereby a projection image without distortion can be formed regardless of the projection angle.

  As described above, in this embodiment, since the projection angle of the projector can be adjusted using the expansion and contraction of the lens barrel 1, an appropriate projection angle without image vignetting can be set. By using the lens barrel 1, a dedicated angle adjustment mechanism is not necessary, and it is possible to suppress an increase in cost and an increase in the size of the camera. Further, since the stability of the camera is not sacrificed, the shake of the projected image can be suppressed.

  In order to further improve the stability of the camera, for example, a flat cut portion P as shown in FIG. 6 may be formed at the tip of the cylindrical body 1B. The flat cut portion P is provided at a position and an angle at which it can come into surface contact with the placement surface when the projection angle is large as shown in FIG. 5C, and is in line contact in FIG. 5B. Therefore, the camera can be supported more stably. Incidentally, if the plane cut portion P is not provided, the cylindrical body 1B and the placement surface are always in point contact.

Further, when there is a concern that the lens barrel 1 is undesirably brought in due to the weight load of the camera body 100 during projection, the following prevention measures are required, for example.
FIG. 8 shows a part of a lens driving mechanism (cam mechanism). A cam follower CF provided on the cylindrical bodies 1A and 1B is engaged with a cam surface CP provided on the rotary cylinder, and the cylindrical body is rotated with the rotation of the rotary cylinder. In this structure, 1A and 1B are linearly driven. Undesirable retraction of the cylinders 1A and 1B occurs when a right force is applied to the cam follower CF due to the weight load of the camera body 100, and the cam surface CP is pushed down (rotates the rotating body). Therefore, when the cam follower CF reaches a position corresponding to the lens barrel feeding amount (for example, the wide-angle end position or the maximum feeding position) at the time of projection, it is undesirable to fall into the step of the cam surface CP. The movement of the cam surface CP, that is, the retraction of the cylinders 1A and 1B can be suppressed.

  In the above, an example in which the projection angle can be changed in two steps has been shown, but it may be three or more steps or stepless (can be projected at an arbitrary feeding position).

  FIG. 9 shows an example in which the height of the projection optical axis can be changed by expanding and contracting the lens barrel 1. In this case, although the vignetting prevention effect is lower than the change in the projection angle as described above, the projection window may be provided on either the side surface, the top surface, or the bottom surface of the camera, in addition to the high degree of freedom in arrangement. The trapezoidal correction control according to the projection angle is unnecessary. The projection direction may not be the horizontal direction. In addition, since the camera body 100 is supported only by the lens barrel 1, it is desirable to dispose the lens barrel 1 at the center of the camera body 100.

The perspective view of the digital camera with a built-in projector in one embodiment of the present invention. The perspective view which looked at the said camera from another angle. Sectional drawing which shows the structure of a projector module. The schematic block diagram which shows the control system of a camera. The figure explaining the projection method with a camera. The figure explaining the plane part provided in the front-end | tip of a lens-barrel. The flowchart explaining the process at the time of zoom button operation. The figure which shows a part of lens drive mechanism. The figure which shows an example of the camera which can change the height of a projection optical axis.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lens barrel 1A, 1B 1st, 2nd cylinder 3 Projection window 5 Zoom button 22 Projector drive part 23 Lens barrel drive part 24 Zoom motor 30 Projector module 100 Camera main body P Plane cut part X Projection optical axis

Claims (8)

A taking lens barrel that expands and contracts with respect to the camera body;
When a part of the camera body and a part of the photographic lens barrel are brought into contact with the mounting surface, the projection angle of the image is changed according to a change in the posture of the camera body due to expansion and contraction of the photographic lens barrel. A projector built-in camera comprising: a projector unit that changes. The camera with a built-in projector according to claim 1, further comprising a correcting unit that performs a process of correcting distortion of a projected image that may occur according to the projection angle based on an expansion / contraction state of the photographing lens barrel. . A taking lens barrel that expands and contracts with respect to the camera body;
A projector unit that changes the height of the projection optical axis of the image according to a change in the height of the camera body due to expansion and contraction of the photographing lens barrel when the photographing lens barrel is brought into contact with the mounting surface; A camera with a built-in projector. When projection is performed with a part of the camera body and a part of the photographing lens barrel in contact with the mounting surface, the top and bottom direction of the projected image matches the top and bottom direction of the original image. The projector built-in camera according to claim 1, wherein an arrangement of the projector unit is defined. 5. The projector built-in camera according to claim 1, wherein the photographing lens barrel is a zoom lens barrel that changes a photographing angle of view by the expansion and contraction. 6. The projecting lens barrel is configured such that at least two projection expansion / contraction states are determined in advance in the expansion / contraction movable range of the photographing lens barrel, and any of the projection expansion / contraction states can be selected by an operation. The camera with a built-in projector according to any one of the above. 7. The expansion / contraction drive mechanism of the photographing lens barrel is provided with a mechanism for preventing the photographing lens barrel from contracting due to a weight load of the camera body in each of the projection expansion / contraction states. The projector built-in camera as described. The flat surface part for ensuring the stability of a camera is formed in the location which contact | abuts the said mounting surface of the said taking lens-barrel, The any one of Claims 1-7 characterized by the above-mentioned. Camera with built-in projector.

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