JP4984601B2 - Projection device with zoom mechanism - Google Patents

Description

The present invention relates to a projection apparatus with a zoom mechanism, in particular, according to the setting of the zoom range.

  In a projection apparatus in which light from a light source is modulated by a video signal by a display element and projected onto a screen by a projection lens, zoom is set by moving the projection lens as disclosed in Patent Document 1. This zoom range is set so that it is equal to or larger than the resolution limit allowable value at the position closest to the end of the lens on the screen.

  That is, in the projection apparatus, as shown in FIG. 22, the projection lens 102 is arranged with respect to the display element 101. In the standard system, the aspect ratio of the screen is a horizontally long screen of (4: 3), and a display element having an aspect ratio (4: 3) is arranged horizontally long as the display element 101.

  The performance of the lens is best at its central part and tends to deteriorate as it reaches the end. Accordingly, the zoom range is set so that the required resolution performance allowable limit value is maintained at the diagonal end positions Pa101 and Pa102 where the end of the lens is used in the area A101 of the screen. Must be set. Other parts of the screen area A101 are closer to the optical axis than the positions Pa101 and Pa102. It can be said that the allowable resolution performance limit value is maintained. From this, it can be said that the zoom setting range depends on the distance from the center of the optical axis to the diagonal end, that is, the image height.

  Here, it is assumed that a vertically long screen having an aspect ratio (3: 4) is displayed on the display element 101 having an aspect ratio (4: 3) arranged horizontally. In this case, as shown in FIG. 23, the image height is smaller than when the image is displayed on the landscape screen. That is, as shown in FIG. 23, the maximum image height is the distance Ha101 in the area A101 when the screen is horizontally long. On the other hand, in the region B101 in the case of a vertically long screen, the maximum image height is the distance Hb101, and the image height is clearly reduced. Therefore, it is considered that the zoom range can be expanded when a vertically long screen is displayed with a horizontally long display element.

  This relationship applies not only to the projection apparatus but also to the imaging apparatus. In the imaging apparatus, a captured image is condensed on an imaging element by an imaging lens, photoelectrically converted by the imaging element to capture an image, and a lens barrel is moved to set zoom. This zoom range is set so that it is equal to or larger than the resolution limit allowable value at the position closest to the end of the lens on the screen.

  That is, in the imaging apparatus, as shown in FIG. 24, the imaging lens 112 is arranged with respect to the imaging element 111. In the standard system, a horizontally long image sensor is used as the image sensor 111.

  The performance of the lens is best at its central part and tends to deteriorate as it reaches the end. Accordingly, the zoom range is set so as to maintain the required resolution performance allowable limit value at the diagonal end positions Pa111 to Pa114 in which the end of the lens is used in the area A111 of the screen. Must be set. The other part of the screen area A111 is closer to the optical axis than the positions Pa111 to Pa114. Therefore, if the resolution performance allowable limit value required at the positions Pa111 to Pa114 is maintained, it is necessary at other positions. It can be said that the allowable resolution performance limit value is maintained. From this, it can be said that the zoom setting range depends on the distance from the center of the light source to the diagonal end, that is, the image height.

Here, it is assumed that a vertically long screen is imaged on the image sensor 111 arranged horizontally. In this case, as shown in FIG. 25, the image height is smaller than when the image is taken on the landscape screen. That is, as shown in FIG. 25, the maximum image height is the distance Ha111 in the area A111 in the case of a landscape screen. On the other hand, in the region B111 in the case of a vertically long screen, the maximum image height is the distance Hb111, and the image height is clearly reduced. Therefore, it is considered that the zoom range can be expanded when a horizontally long image pickup device is used to image a vertically long screen.
JP 2006-47683 A

  As described above, in the projection device, for example, when a vertically long screen is displayed on a horizontally long display element, the image height becomes small. From this, it is considered that the zoom range can be expanded when a vertically long screen is displayed. However, conventionally, the zoom range is set to be the same both when displaying a landscape screen and when displaying a portrait screen.

  Similarly, in an imaging apparatus, for example, when a vertically long screen is imaged on an image sensor arranged horizontally, the image height decreases. From this, it is considered that the zoom range can be expanded when capturing a vertically long screen. However, conventionally, the zoom range is set to be the same both when capturing a horizontally long screen and when capturing a vertically long screen.

  In view of the above-described problems, an object of the present invention is to provide a projection device with a zoom and an imaging device that can maximize the zoom range according to the mode.

  In order to solve the above-described problems, the present invention sets a display element that modulates light from a light source by a video signal, a projection lens that projects light from the display element onto a screen, and a zoom of the projection lens. A lens moving unit; a mode setting unit that selectively sets a plurality of modes having different image heights; and a control unit that sets a zoom range so as to expand a zoom range of the projection lens in a mode in which the image height decreases. And a zoom mechanism-equipped projection device.

According to the present invention, in the mode in which the image height is reduced, the image can be further enlarged by setting the zoom range so as to enlarge the zoom range. In the projection device, for example, the zoom range can be expanded at the time of a portrait screen, a wide screen, or a keystone correction .

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 1 shows the configuration of the projection apparatus according to the first embodiment of the present invention. In FIG. 1, an image signal is supplied to the input terminal 11. An image signal from the input terminal 11 is digitized by an A / D converter 12 and sent to a DMD (Digital Micromirror Device) drive circuit 13. The DMD driving circuit 13 performs video signal processing such as synchronization separation, YC separation, IP conversion, resolution conversion, color conversion, and keystone correction on various input image signals according to the form of the input image signal. Here, YC separation is processing for separating a luminance signal and a chroma signal. IP conversion is conversion from interlace scanning to progressive scanning. Then, the DMD driving circuit 13 forms an RGB frame sequential image signal based on the input image signal. This frame sequential image signal is supplied to the DMD element 14 as a DMD drive signal.

  The DMD element 14 is a spatial light modulation element in which a number of minute mirrors are arranged on the surface and the angle can be changed for each pixel. When the DMD drive signal from the DMD drive circuit 13 is applied to the DMD element 14, the angle of the minute mirror on the surface of the DMD element 14 is changed, thereby changing the light path, and turning on / off the light in pixel units. Is done.

  The vertical synchronization signal separated by the DMD drive circuit 13 is supplied to the timing generation circuit 15. In the timing generation circuit 15, a timing signal is formed based on the vertical synchronization signal of the input video signal. This timing signal is supplied to the motor drive circuit 16. The color wheel 17 is a wheel that is divided into three colors of R, G, and B. The color wheel 17 is rotated by the motor driving circuit 16 in synchronization with the vertical synchronizing signal of the input video signal.

  The light source 21 is driven by the light source driving circuit 20 under the control of the controller 1. Light from the light source 21 is applied to the DMD element 14 via the lens 22 and the color wheel 17. Thereby, the DMD element 14 is sequentially irradiated with RGB light in synchronization with the vertical synchronization signal of the input image signal.

  The DMD element 14 is supplied with a frame sequential image signal from the DMD driving circuit 13 as a DMD driving signal. The angle of the minute mirror on the surface of the DMD element 14 is changed by the DMD drive signal, and the light path is changed. For this reason, the reflected light of the DMD element 14 is modulated in units of pixels by the DMD drive signal from the DMD drive circuit 13. The light modulated by the DMD drive signal is enlarged as projection light through the projection lens 23 and projected onto the projection surface 24. As a result, an image is projected on the projection surface 24. The projection lens 23 is moved by a lens motor 25. The zoom is set by moving the projection lens 23 by the lens motor 25.

  The controller 1 controls the overall operation of the projection apparatus. The controller 1 is provided with various inputs from the input key 2 and inputs from the portrait / landscape mode switch 3 and the zoom switch 4. When the zoom switch 4 is operated, a lens drive signal is supplied from the controller 1 to the zoom motor drive circuit 26, whereby the lens motor 25 serves as a lens moving means, and zoom is set.

  The portrait / landscape mode switch 3 is a switch (mode setting means) for switching between the landscape mode and the portrait mode. In the landscape mode, as shown in FIG. 2A, a landscape screen with an aspect ratio of, for example, (4: 3) is projected. In the portrait mode, as shown in FIG. 2B, a portrait screen with an aspect ratio of, for example, (3: 4) is projected.

  In the first embodiment of the present invention, as described above, the projection apparatus has a zoom function and can set the landscape mode and the portrait mode. In the above example, a DLP (Digital Light Processing) type projection apparatus using a DMD element is used, but the present invention is not limited to such a type of projection apparatus. The present invention can be similarly applied to the case of a CRT type projection apparatus or a liquid crystal projection apparatus.

  In the first embodiment of the present invention, the horizontally long mode and the vertically long mode can be set using the horizontally long DMD element 14. When the portrait mode is set, the zoom movement range can be expanded compared to the case where the landscape mode is set. This will be described below.

  When designing a projection lens of a projection apparatus having a zoom function, the projection lens is designed so that the maximum image height due to the arrangement of the display element (in this case, the DMD element 14) is equal to or greater than the required resolution performance allowable value. ing. The performance of the lens is best at its central part and tends to deteriorate as it reaches the end. Therefore, it is necessary to set the zoom range so as to maintain the required resolution performance allowable limit value at the diagonal end where the end of the lens is used in the image.

  For example, a horizontally long element having an aspect ratio of, for example, (4: 3) is normally used as a display element, and a horizontally long screen of (4: 3) is projected in the horizontally long mode. On the other hand, in the case of the portrait mode, a portrait screen of (3: 4) is projected onto a landscape display element having an aspect ratio of (4: 3), for example. In this case, as shown in FIG. 2B, the image height is smaller than in the case of the landscape screen. From this, it is considered that the zoom movement range that can be set is wider in the portrait mode than in the landscape mode.

  FIG. 3 illustrates this in more detail. FIG. 3A shows the positional relationship between the projection lens and the projection screen, and FIG. 3B shows the relationship between the zoom magnification at each point on the lens and MTF (Modulation Transfer Function). MTF is an index for evaluating lens performance, and expresses as a spatial frequency characteristic how accurately the contrast of a subject can be reproduced in order to know the imaging performance of the lens.

  In FIG. 3A, when a landscape screen is projected, the relationship between the projection lens and the image is as shown by a region A11. That is, in the horizontally long screen, the diagonal end (end along the diagonal passing through the optical axis on the screen) is the position Pa11, and the short side end (end along the short side passing through the optical axis on the screen) is the position Pa12. The side end (end along the long side passing through the optical axis on the screen) is the position Pa13. The relationship between the zoom magnification of each position Pa11 to Pa13 of the region A11 and the MTF in the landscape display is as shown by curves Qa11 to Qa13 in FIG.

  In the region A11 of the landscape display screen, the diagonal end is at the end of the lens at the position Pa11, so that the MTF is the worst, and the characteristic Qa11 in FIG. Since the short-side end position Pa12 is next away from the center of the lens, the MTF at the short-side end position Pa12 is the next worst, as shown in the characteristic Qa12 in FIG. Since the position Pa13 of the long side end is closest to the center of the lens, the MTF is the best, and the characteristic Qa13 is obtained in FIG. In the horizontally long screen, it is necessary to set the zoom range so that the diagonal end closest to the end of the lens is the position Pa11 and a satisfactory MTF (greater than or equal to the allowable resolution limit) can be obtained.

  On the other hand, when a vertically long screen is projected, the relationship between the projection lens and the image is as shown by a region B11. In the vertically long screen, the MTF characteristic at the diagonal end position Pb11 farthest from the center of the lens is the characteristic Qb11 in FIG. In the portrait screen, the zoom range may be set so that the MTF at the diagonal end position Pb11 in the portrait display is satisfied.

  As can be seen by comparing the characteristics Qa11 and the characteristics Qb11, the MTF at the diagonal end is better in the case of the vertically long screen than in the case of the horizontally long screen. Accordingly, assuming that the zoom range La1 is set so that satisfactory image quality can be secured at the diagonal end position Pa11 that is closest to the end of the lens on the horizontally long screen, the same MTF characteristics are obtained when the vertically long screen is used. Can be expanded to Lb1.

  Therefore, in the first embodiment of the present invention, as shown in FIG. 4, the controller 1 (control means) determines whether the landscape mode or the portrait mode is set, and the portrait mode or landscape mode is set. The zoom range is set accordingly. That is, as shown in FIG. 4, it is determined whether the mode is the landscape mode or the portrait mode (step S11). In the landscape mode, the zoom range is set to La1 (step S12). In the case of the portrait mode, the zoom range is expanded to Lb1 (step S13).

  As described above, in the first embodiment of the present invention, the landscape mode and the portrait mode can be set. When the portrait mode is set, the zoom movement range is expanded compared to the case of the landscape mode. Is done. For this reason, it becomes possible to project a further enlarged screen in the portrait mode.

<Second Embodiment>
FIG. 5 shows a second embodiment of the present invention. In this embodiment, a mode switch 5 (mode setting means) for setting the standard screen mode and the wide screen mode is provided. In the standard screen mode, as shown in FIG. 6A, a standard screen with an aspect ratio of (3: 4) is projected. In the wide screen mode, as shown in FIG. 6B, a wide screen having an aspect ratio of (16: 9) is projected. In the second embodiment of the present invention, as shown in FIG. 6, when the wide screen is set, the image light is smaller than that of the standard screen. Therefore, when the wide screen mode is set, Compared to the standard screen mode, the zoom movement range is extended. About another structure, it is the same as that of the above-mentioned 1st Embodiment.

  FIG. 7 explains this. FIG. 7A shows the positional relationship between the projection lens and the projection screen, and FIG. 7B shows the relationship between the zoom magnification and the MTF at each point on the lens.

  In FIG. 7A, when the standard screen of (3: 4) is projected, the relationship between the projection lens and the projection screen is as shown by a region A21. That is, on the standard screen, the diagonal end is the position Pa21, the short side end is the position Pa22, and the long side end is the position Pa23. The relationship between the zoom magnification of each position Pa21 to Pa23 of the area A21 and the MTF in the standard screen is as shown by curves Qa21 to Qa23 in FIG. 7B.

  In the area A21 of the standard screen, the diagonal end is at the end of the lens at the position Pa21, so that the MTF is the worst, and the characteristic Qa21 in FIG. 7B is obtained. Since the short-side end position Pa22 is next away from the center of the lens, a characteristic Qa22 is obtained in FIG. Since the position Pa23 of the long side end is closest to the center of the lens, the MTF is the best, and the characteristic Qa23 is obtained in FIG. In the standard screen, it is necessary to set the zoom range so that the diagonally long display diagonal end closest to the end of the lens is at position Pa21 and a satisfactory MTF (greater than the resolution limit) is obtained.

  On the other hand, when a wide screen is projected, the relationship between the projection lens and the projection screen is as shown by a region B21. In the wide screen, the MTF characteristic at the diagonal end position Pb21 farthest from the center of the lens is as indicated by a characteristic Qb21 in FIG. 7B. In the wide screen, the zoom range may be set so that the MTF at the diagonal position Pb21 is satisfactory.

  As can be seen by comparing the characteristics Qa21 and Qb21, the MTF at the diagonal end is better in the case of the wide screen than in the case of the standard screen. Accordingly, if the zoom range La2 is set so that satisfactory image quality can be secured at the diagonal end position Pa21 closest to the end of the lens in a horizontally long image, the same MTF is set when the wide screen is set. Can be expanded to Lb2.

  Therefore, in the second embodiment of the present invention, as shown in FIG. 8, the controller 1 (control means) determines whether the standard screen mode or the wide screen mode is set, and the standard screen mode is set. The zoom range is set according to the wide screen mode. That is, as shown in FIG. 8, it is determined whether the screen mode is a standard screen mode with an aspect ratio of (4: 3) or a wide screen mode with an aspect ratio of (16: 9) (step S21). In the case of the standard screen mode, the zoom range is set to La2 (step S22). In the wide screen mode, the zoom range is extended to Lb2 (step S23).

  As described above, in the second embodiment of the present invention, the standard screen mode and the wide screen mode can be set. When the wide screen mode is set, the zoom is smaller than when the standard screen mode is set. The movement range is extended. For this reason, it becomes possible to project a further enlarged screen in the wide screen mode.

<Third Embodiment>
FIG. 9 shows a third embodiment of the present invention. In this embodiment, a trapezoidal correction setting switch 6 (mode setting means) is provided, and the trapezoidal correction correction according to the distortion can be performed by the trapezoidal correction setting switch 6.

  When trapezoidal distortion is performed, a screen distorted into a trapezoid as shown in FIG. 10A is corrected as shown in FIG. In the trapezoidal correction, a part of the screen is cut out and corrected, so that the image height of the screen is reduced as shown in FIG. For this reason, the zoom movement range that can be set can be expanded when keystone correction is performed. About another structure, it is the same as that of the above-mentioned 1st Embodiment.

  FIG. 11 explains this in detail. FIG. 11A shows the positional relationship between the projection lens and the projection image, and FIG. 11B shows the relationship between the zoom magnification and the MTF at each point on the lens.

  In FIG. 11A, when the projection is performed on the full screen (the screen on which the keystone correction is not performed), the relationship between the projection lens and the projection screen is as shown by a region A31. That is, on the full screen, the diagonal end is the position Pa31, the short side end is the position Pa32, and the long side end is the position Pa33. The relationship between the zoom magnification of each position Pa31 to Pa33 of the area A31 and the MTF in the standard screen is as shown by curves Qa31 to Qa33 in FIG.

  In the full-screen area A31, the diagonal end position Pa31 is at the end of the lens, so the MTF is the worst, and the characteristic Qa31 in FIG. 11B is obtained. Since the short-side end position Pa32 is next away from the center of the lens, a characteristic Qa32 is obtained in FIG. Since the position Pa33 of the long side end is closest to the center of the lens, the MTF is the best, and the characteristic Qa32 is obtained in FIG. In the full screen, it is necessary to set the zoom range so that a satisfactory MTF (greater than or equal to the allowable resolution limit) can be obtained at the diagonal position Pa31 closest to the end of the lens.

  On the other hand, when trapezoidal correction is performed, the relationship between the projection lens and the image is as shown by a region B31. In the trapezoidally corrected screen, the MTF characteristic at the diagonal end position Pb31 farthest from the center of the lens is the characteristic Qb31 in FIG. In a screen with trapezoidal correction, the zoom range may be set so that the MTF at the diagonal position Pb31 is satisfactory.

  As can be seen from a comparison between the characteristics Qa31 and the characteristics Qb31, the MTF at the diagonal end is better in the case of the screen with the trapezoidal correction than in the case of the full screen. Therefore, assuming that the diagonal end closest to the end of the lens in the landscape image is at position Pa31 and the zoom range La3 is set so that satisfactory image quality can be secured, in the case of a trapezoidally corrected screen, the same MTF is used. Can be expanded to Lb3.

  In the third embodiment of the present invention, as shown in FIG. 12, the zoom range is set according to whether or not the keystone correction has been performed by the controller 1 (control means). That is, as shown in FIG. 12, it is determined whether or not keystone correction is performed (step S31). In the case of a full screen without keystone correction, the zoom range is set to La3 (step S32). If trapezoidal correction is performed, the zoom range is expanded to Lb3 according to the correction rate (step S33).

  As described above, in the third embodiment of the present invention, when the keystone correction is performed, the zoom movement range is expanded compared to the display on the full screen. For this reason, it is possible to project a further enlarged screen on the screen subjected to the keystone correction.

<Fourth Embodiment>
FIG. 13 shows a fourth embodiment of the present invention. In the first to third embodiments described above, the present invention is applied to the projection apparatus. On the other hand, this embodiment is applied to an imaging apparatus.

  In FIG. 13, an optical image of the subject via the imaging lens 50 is formed on the imaging element 51. The image sensor 51 photoelectrically converts subject image light formed on the light receiving surface. As the image sensor 51, a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary MOS) image sensor is used. Color filters are arranged on the front surface of the image sensor. As the arrangement of the color filters, there are a case where R, G and B primary color filters are used and a case where a complementary color filter of Cy (cyan), Mg (magenta) and Ye (yellow) is used.

  An output signal of the image sensor 51 is supplied to an A / D converter 53 via a CDS (Correlated Double Sampling) and an AGC (Automatic Gain Control) circuit 52. The image signal is digitized by the A / D converter 53. The output signal of the A / D converter 53 is taken in via the image input controller 54.

  The output signal of the image sensor 51 is digitized by the A / D converter 53 via the CDS and AGC circuit 52 and then supplied to the process circuit 56. The process circuit 56 performs image processing such as gamma correction, edge enhancement, and white balance. This image signal is once taken into the memory 57. This image signal is supplied to the video encoder 58. A component color video signal is formed by the video encoder 58, this color video signal is supplied to the monitor 61, and the monitor image being shot is displayed on the monitor 61.

  When taking an image, the shutter button 70 is pressed. When the shutter button 70 is pressed, the image at that time is taken into the image sensor 51, and the image signal for one screen at this time is stored in the memory 57.

  The image signal for one screen captured in the memory 57 is supplied to the image compression / decompression circuit 59. The image compression / decompression circuit 59 compresses and encodes the image data. For example, JPEG (Joint Photographic Experts Group) is used as a compression method of image data. JPEG is a standard for compressing an image using DCT (Discrete Course Transform). Note that the image data compression method is not limited to JPEG.

  The compressed and encoded image signal is supplied to the recording medium 62 via the memory controller 60 and recorded on the recording medium 62. As the recording medium 62, a card-type removable memory using a flash memory is used.

  In the reproduction mode, an image file on the recording medium 62 is opened and image data is read out. The image data read from the recording medium 62 is supplied to the image compression / decompression circuit 59. The image compression / decompression circuit 59 performs image signal decompression processing. The output of the image compression / decompression circuit 59 is supplied to the video encoder 58. An output signal of the video encoder 58 is supplied to the monitor 61, and a reproduced image is displayed on the monitor 61.

  The controller 63 controls the entire imaging apparatus. The controller 63 is given a shutter input from the shutter button 70 and various inputs from the input key 64. The controller 63 is provided with a zoom switch 65. When the zoom switch 65 is operated, a control signal is supplied to the zoom motor drive circuit 66, whereby the motor 71 (lens moving means) is driven and the zoom is varied.

  In the fourth embodiment of the present invention, a landscape image sensor 51 is used, and a portrait / landscape mode switch 67 (mode setting means) for setting the portrait mode and landscape mode is provided. When the portrait mode is set, the zoom movement range is expanded as compared with the landscape mode.

  FIG. 14 explains this in detail. FIG. 14A shows the positional relationship between the imaging lens and the imaging screen, and FIG. 14B shows the relationship between the zoom magnification and the MTF at each point on the lens.

  In FIG. 14A, when shooting a landscape screen, the relationship between the photographic lens and the image is as shown by a region A41. That is, on the horizontally long screen, the diagonal end is the position Pa41, the long side end is the position Pa42, and the short side end is the position Pa43. The relationship between the zoom magnification of each position Pa41 to Pa43 of the area A41 and the MTF in the landscape screen is as shown by curves Qa41 to Qa43 in FIG.

  In the region A41 of the landscape screen, the diagonal end is at the end of the lens at the position Pa41, so that the MTF is the worst, and the characteristic Qa41 in FIG. 14B is obtained. Since the position Pa42 at the long side edge is next away from the center of the lens, the MTF at the position Pa42 at the long side edge is next worse, as shown in the characteristic Qa42 in FIG. Since the position Pa43 of the short side end is closest to the center of the lens, the MTF is the best, and the characteristic Qa43 is obtained in FIG. In the horizontally long screen, it is necessary to set the zoom range to a range where a satisfactory MTF (greater than or equal to the allowable resolution limit) can be obtained at the diagonal end position Pa41 closest to the lens end.

  On the other hand, when the image is taken on a vertically long screen, the relationship between the taking lens and the image is as shown by a region B41. In the vertically long screen, the MTF characteristic at the diagonal end position Pb41 farthest from the center of the lens is as shown by a characteristic Qb41 in FIG. In the vertically long screen, the zoom range may be set so that the MTF at the diagonal end position Pb41 in the vertically long display is satisfied.

  As can be seen by comparing the characteristic Qa41 and the characteristic Qb41, the MTF at the diagonal end is better when shooting on a vertically long screen than when shooting on a horizontally long screen. Accordingly, assuming that the diagonal end closest to the end of the lens on the landscape screen is at position Pa41 and the zoom range La4 is set so that satisfactory image quality can be ensured, the same MTF is obtained for the portrait screen. The zoom range that can be extended to Lb4.

  Therefore, in the fourth embodiment of the present invention, as shown in FIG. 15, the controller 63 (control means) determines whether the landscape mode or the portrait mode is set, and the landscape mode or portrait mode is set. The zoom range is set accordingly. That is, as shown in FIG. 14, it is determined whether the mode is the landscape mode or the portrait mode (step S41). In the landscape mode, the zoom range is set to La4 (step S42). In the case of the portrait mode, the zoom range is expanded to Lb4 (step S43).

  As described above, in the fourth embodiment of the present invention, the shooting in the landscape mode and the shooting in the portrait mode can be set. When the portrait mode is set, the zoom is compared with the case of the landscape mode. The movement range is extended. For this reason, it becomes possible to photograph a further enlarged screen in the portrait mode.

<Fifth Embodiment>
FIG. 16 shows a fifth embodiment of the present invention. In this embodiment, a panorama setting switch 68 (mode setting means) for setting the normal shooting mode and the panorama shooting mode is provided. When the panorama shooting mode is set, the zoom movement range is extended compared to the case where the normal shooting mode is set. Other configurations are the same as those in the fourth embodiment described above.

  FIG. 17 explains this in detail. FIG. 17A shows the positional relationship between the imaging lens and the imaging screen, and FIG. 17B shows the relationship between the zoom magnification and the MTF at each point on the lens.

  In FIG. 17A, in the case of normal shooting, the relationship between the shooting lens and the imaging screen is as shown by a region A51. That is, on the normal shooting screen, the diagonal end is the position Pa51, the long side end is the position Pa52, and the short side end is the position Pa53. The relationship between the zoom magnification of each position Pa51 to Pa53 of the area A51 and the MTF in the normal shooting mode screen is as shown by curves Qa51 to Qa53 in FIG.

  In the area A51 of the screen in the normal shooting mode, the diagonal end position Pa51 is closest to the end of the lens, so the MTF is the worst, and the characteristic Qa51 is as shown in FIG. Since the position Pa52 at the long side edge is next away from the center of the lens, the MTF at the position Pa52 at the long side edge is next worse, and the characteristic Qa52 is obtained in FIG. Since the position Pa53 of the short side end is closest to the center of the lens, the MTF is the best, and the characteristic Qa53 is obtained in FIG. In normal shooting, it is necessary to set a zoom range where a satisfactory MTF (greater than or equal to the resolution limit) is obtained at the diagonal end position Pa51 closest to the lens end.

  On the other hand, when a panorama is photographed, the relationship between the photographing lens and the imaging screen is as shown by a region B51. On the screen in the panoramic shooting mode, the MTF characteristic at the diagonal end position Pb51 farthest from the center of the lens is as indicated by a characteristic Qb51 in FIG. On the panorama shooting mode screen, the zoom range may be set so that the MTF at the diagonal position Pb51 of the region B51 is satisfied in the panorama shooting mode.

  As can be seen from the comparison between the characteristics Qa51 and Qb51, the MTF at the diagonal end is better in the panoramic shooting mode than in the normal shooting mode. Therefore, assuming that the diagonal end closest to the end of the lens in the normal shooting mode is at position Pa51 and the zoom range La5 is set so that satisfactory image quality can be secured, in the case of a panoramic screen, a similar MTF is obtained. The resulting zoom range can be extended to Lb5.

  Therefore, in the fifth embodiment of the present invention, as shown in FIG. 18, the controller 63 (control means) determines whether the normal shooting mode or the panoramic shooting mode is set, and normal shooting is performed. The zoom range is set according to the mode or panoramic shooting mode. That is, as shown in FIG. 18, it is determined whether the mode is the normal shooting mode or the panoramic shooting mode (step S51). In the normal shooting mode, the zoom range is set to La5 (step S52). In the case of panoramic shooting, the zoom range is extended to Lb5 (step S53).

  As described above, in the fifth embodiment of the present invention, the normal shooting mode and the panorama shooting mode can be set. When the panorama shooting mode is set, the zoom is smaller than when the normal shooting mode is set. The movement range is extended. For this reason, it is possible to shoot a further enlarged screen in the panoramic shooting mode.

<Sixth Embodiment>
FIG. 19 shows a sixth embodiment of the present invention. In this embodiment, a digital zoom re-enlargement switch 69 (mode setting means) is provided. The digital zoom re-enlargement switch 69 enables the optical zoom to be further expanded according to the set value of the digital zoom when set to the digital zoom. Other configurations are the same as those in the fourth embodiment described above.

  That is, the digital zoom cuts out a part of the screen and performs interpolation for enlargement. Therefore, when the digital zoom is used, the image height is reduced, and the zoom movement range is extended as compared with the case of normal photographing.

  FIG. 20 explains this in detail. FIG. 20A shows the positional relationship between the imaging lens and the imaging screen, and FIG. 20B shows the relationship between the zoom magnification and the MTF at each point on the lens.

  In FIG. 20A, when the digital zoom is not performed, the relationship between the photographing lens and the imaging screen is as shown by a region A61. That is, on a screen without digital zoom, the diagonal end is the position Pa61, the long side end is the position Pa62, and the short side end is the position Pa63. The relationship between the zoom magnification of each position Pa61 to Pa63 of the region A61 and the MTF in the landscape display is as shown by curves Qa61 to Qa63 in FIG.

  In the area A61 of the screen when the digital zoom is not performed, the diagonal end comes to the end of the lens most at the position Pa61, so the MTF is the worst, and the characteristic Qa61 in FIG. 20B is obtained. Since the position Pa62 at the long side edge is next away from the center of the lens, the MTF at the position Pa62 at the long side edge is next worse, as shown in the characteristic Qa62 in FIG. Since the position Pa63 of the short side edge is closest to the center of the lens, the MTF is the best, and the characteristic Qa63 is obtained in FIG. When the digital zoom is not performed, it is necessary to set the zoom range so that the diagonal end closest to the end of the lens is at position Pa61 and a satisfactory MTF (greater than or equal to the allowable resolution limit) can be obtained.

  On the other hand, when the image is taken with the digital zoom, the relationship between the taking lens and the cut-out screen is as shown by a region B61. In the screen cut out by digital zoom, the MTF characteristic at the diagonal end position Pb61 farthest from the center of the lens is the characteristic Qb61 in FIG. When the digital zoom is performed, the zoom range may be set so that the MTF at the diagonal position Pb51 of the cut-out area B61 of the screen is satisfied.

  As can be seen by comparing the characteristic Qa61 and the characteristic Qb61, in the case of a digital zoom screen, the MTF at the diagonal end increases as compared with the case of the screen length of normal shooting. Accordingly, if the zoom range La6 is set so that the diagonal end closest to the end of the lens on the normal screen is at position Pa61 and satisfactory image quality can be secured, in the case of the screen when the digital zoom is performed, The zoom range in which a similar MTF can be obtained can be expanded to Lb6.

  Normally, in an image pickup apparatus equipped with an optical zoom and a digital zoom, when zoom shooting is performed with a zoom switch, as shown in FIG. Above that, the optical zoom is constant and the zoom is set by digital zoom.

  On the other hand, in the sixth embodiment of the present invention, when the digital zoom re-enlargement mode is set, as shown in FIG. 21B, when zoom shooting is performed with the zoom switch, the optical zoom is set. Zooming is performed by optical zoom in a possible range, and zooming is set by digital zoom beyond that. When the zoom is set by digital zoom, the optical zoom range can be expanded according to the zoom ratio of the digital zoom. Thereby, when the digital zoom is performed, the photographing screen can be further enlarged by the optical zoom.

  For example, assuming that the normal optical zoom is 3 times and the digital zoom is 2 times, the zoom magnification is normally (3 × 2 = 6) times. However, when the digital zoom re-enlargement mode is set, when the digital zoom is set to 2 times, the optical zoom is enlarged 3 times or more, and the zoom can be enlarged to a total exceeding 6 times.

  The present invention is not limited to the above-described embodiments, and various modifications and applications are possible without departing from the spirit of the present invention.

  The present invention can be used for zoom setting of a projection apparatus such as a DLP projector or an imaging apparatus such as a digital camera.

It is a block diagram of a 1st embodiment of the present invention. It is explanatory drawing of landscape mode and portrait mode. It is explanatory drawing of the 1st Embodiment of this invention. It is a flowchart used for description of the 1st Embodiment of this invention. It is a block diagram of the 2nd Embodiment of this invention. It is explanatory drawing of standard screen mode and wide screen mode. It is explanatory drawing of the 2nd Embodiment of this invention. It is a flowchart used for description of the 2nd Embodiment of this invention. It is a block diagram of the 3rd Embodiment of this invention. It is explanatory drawing of trapezoid correction. It is explanatory drawing of the 3rd Embodiment of this invention. It is a flowchart used for description of the 3rd Embodiment of this invention. It is a block diagram of the 4th Embodiment of this invention. It is explanatory drawing of the 4th Embodiment of this invention. It is a flowchart used for description of the 4th Embodiment of this invention. It is a block diagram of the 5th Embodiment of this invention. It is explanatory drawing of the 5th Embodiment of this invention. It is a flowchart used for description of the 5th Embodiment of this invention. It is a block diagram of the 6th Embodiment of this invention. It is explanatory drawing of the 6th Embodiment of this invention. It is a graph used for description of the zoom setting by the 6th Embodiment of this invention. It is explanatory drawing which shows the relationship between the image height of the conventional projector, and zoom. It is explanatory drawing which shows the relationship between the image height of the conventional projector, and zoom. It is explanatory drawing which shows the relationship between the image height of the conventional imaging device, and zoom. It is explanatory drawing which shows the relationship between the image height of the conventional imaging device, and zoom.

Explanation of symbols

1: Controller,
13: DMD drive circuit,
14: DMD element,
23: Projection lens
25: Lens motor,
26: Zoom motor drive circuit,
50: Imaging lens,
51: Image sensor,
62: Recording medium
63: Controller
70: Shutter button
71: motor,

Claims (7)

A display element that modulates light from a light source by a video signal;
A projection lens that projects light from the display element onto a screen;
Lens moving means for setting the zoom of the projection lens;
Mode setting means for selectively setting a plurality of modes having different image heights;
In a mode in which the image height is reduced, control means for setting a zoom range so as to expand the zoom range of the projection lens;
A projection apparatus with a zoom mechanism, comprising:   2. The projection apparatus with a zoom mechanism according to claim 1, wherein the modes are a horizontally long mode and a vertically long mode, and the zoom range is expanded in the vertically long mode as compared with the horizontally long mode.   The zoom range in the portrait mode is set to a zoom range that can maintain a quality higher than the quality of the image maintained in the zoom range in the landscape mode. The projection apparatus with a zoom mechanism as described.   2. The projection with a zoom mechanism according to claim 1, wherein the mode includes a standard screen mode and a wide screen mode, and the zoom range is expanded in the wide screen mode as compared with the standard screen mode. apparatus.   The zoom range in the wide screen mode is set so as to maintain a quality that is higher than the quality of the image maintained in the zoom range in the standard screen mode. 5. A projection device with a zoom mechanism according to 4.   2. The mode according to claim 1, wherein the mode is a mode with a trapezoidal correction mode and a mode without a keystone correction, and the zoom range is expanded in the mode with the keystone correction compared to the mode without the keystone correction. The projection apparatus with a zoom mechanism as described. The enlargement of the zoom range in the mode with keystone correction is such that the zoom range can maintain a quality higher than the image quality maintained in the zoom range in the mode without keystone correction. The projection apparatus with a zoom mechanism according to claim 6.

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