JP2009081616A - Projection type video display device and mobile electronic device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection type video display device capable of achieving easy-to-view projection video images with little image blurring by correcting the projection function of a mobile device which is small-sized and light in weight and is easily affected by camera shake and vibrations, and coping with further correction by providing a function of restoring a correction performance after correction. <P>SOLUTION: In the projection type video display device, by setting the projection position of a video image projected and displayed on a screen or the like by a projection means so as to use only a part of the center of a projectable range, even when the projectable range is shifted by the camera shake, the prior projection position can be settled within the projectable range after being shifted, and the projection position can be detained at the prior position. Also, after the correction is performed, by comparing the center of the projection position with the center of the projectable range, calculating a distance and a direction between the centers and gently moving the projection position to the center of the projectable range on the basis of the calculated result, the correction performance is restored without making a user feel the movement of the projection video image. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a projection-type image display device and a portable electronic device, and more particularly to camera shake correction of a mobile projector.

  In recent years, with the development of technologies such as light emitting diodes (LEDs), light sources that are small and generate little heat have been put into practical use. By adopting this LED as a light source, it became possible to provide a portable small projector. For example, Patent Document 1 discloses a projector that can be reduced in size and thickness.

  By the way, as a result of promoting the mobile use of projectors, the problem of camera shake during video projection has occurred. In order to solve these problems, for example, Patent Documents 2 to 5 disclose projectors having a function for correcting camera shake.

  In particular, Patent Document 2 discloses a projector that detects the direction and size of camera shake using a CCD sensor and performs correction using the detection result. Specifically, by setting the projection position of the image projected on the screen to use only a part of the projectable range, even if the projectable range is shifted due to camera shake, it is within the projectable range after the shift. The previous projection position can be stored, and the projection position can be kept at the previous position.

Further, in Patent Document 6, as having a complementary role to the above-described conventional technology, the distance between the projection device and the projection position is always measured with sufficiently high accuracy regardless of the distance to the projection position, and the projection is performed. A projection device capable of accurately focusing an image to be performed is disclosed.
JP 2005-107062 A JP 2005-128506 A JP 2007-36843 A JP 2005-292563 A JP 2005-326557 A Japanese Patent Laid-Open No. 2005-62455

  However, when correction as in Patent Document 2 is performed, there is a problem that the allowable range of correction after correction is narrowed. Specifically, once camera shake has been corrected, if further camera shake occurs in the same direction, the previous projection position will not fit within the possible projection range after camera shake, so the projection position should remain at the previous position. The problem that cannot be done.

  The present invention corrects the projection function of a mobile device that is small and lightweight and is easily affected by camera shake and vibration, thereby realizing a projected image with less screen blurring and providing a function for restoring correction performance after correction. Accordingly, it is an object of the present invention to provide a projection type video display apparatus that can cope with further correction.

  Invention of Claim 1 was made | formed in order to achieve the said objective, In a projection type video display apparatus, the projection means which projects video light on a part of projectable range via a projection lens, A blur detection unit that detects a direction and a size of a blur generated during projection of an image by the projection unit; and a control unit that controls a projection position of an image projected and displayed by the projection unit. Corrects the blur of the projected video based on the detection result of the blur detection means, and after the correction is made, if the projected position of the video is deviated from the center of the projectable range, the projected position is It is characterized by moving at a predetermined speed to the center of the projectable range.

  According to a second aspect of the present invention, in the projection display apparatus according to the first aspect, the control means compares the center of the projection position with the center of the projectable range, and the distance and direction between the centers. And the projection position is moved to the center of the projectable range at a predetermined speed based on the calculation result.

  According to a third aspect of the present invention, in the projection type image display device according to the first or second aspect, the control unit is configured to blur the projected video within the projectable range based on a detection result of the blur detection unit. When it cannot correct | amend, the said projection image | video is projected on the position which is settled in the said projectable range.

  According to a fourth aspect of the present invention, in the projection-type image display device according to any one of the first to third aspects, the shake detection unit is configured by an acceleration sensor that detects the direction and size of the shake. It is characterized by that.

  According to a fifth aspect of the present invention, in the projection type image display device according to any one of the first to fourth aspects, the projection means is composed of a light source composed of LEDs and a plurality of micromirrors. DMD, and the control means controls the inclination of the plurality of micromirrors to project the projected video onto a part of the projectable range.

  According to a sixth aspect of the present invention, in the projection-type image display device, the light source configured by the LED and the DMD configured by the plurality of micromirrors are provided, and the inclination of the plurality of micromirrors is controlled. Projection means for projecting image light onto a part of the projectable range via a projection lens, and an acceleration sensor for detecting the direction and size of blurring generated when the projection means projects and displays the image. Control means for controlling the projection position of the image projected and displayed by the projection means, wherein the control means corrects the shake of the projected image based on the detection result of the acceleration sensor, and the shake detection means Based on the detection result, if the blur of the projected image cannot be corrected within the projectable range, the projected image is projected at a position that falls within the projectable range, and the correction is not performed. After that, when the projection position of the image is deviated from the center of the projectable range, the center of the projection position and the center of the projectable range are compared, the distance and direction between the centers are calculated, Based on the calculation result, the projection position is moved to the center of the projectable range at a predetermined speed.

  According to a seventh aspect of the present invention, in the portable electronic device, the projection type video display device according to any one of the first to sixth aspects is provided.

  According to the present invention, by correcting the projection function of a mobile device that is small and light and easily affected by camera shake and vibration, it is possible to realize a projected image with less screen blur and easy to see. In addition, it is possible to provide a projection display apparatus capable of supporting further correction by providing a function of recovering correction performance after correction.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an external perspective view of a mobile phone with a projection display function (hereinafter referred to as a mobile phone) according to an embodiment of the present invention. As shown in FIG. 1, a mobile phone 100 according to the present embodiment is incorporated in a telephone unit 104 including a receiving unit 102 and a transmitting unit 103 that are foldably connected by a hinge unit 101, and the receiving unit 102. And the projection module 105.

  A liquid crystal display monitor 106 and a reception speaker 107 are provided on the inner surface side of the reception unit 102. On the inner surface side of the transmitter 103, a transmitter microphone 108 and an operation unit 4 are provided. The operation unit 4 constitutes a part of the projection module 105.

  The operation unit 4 includes a power button for turning on / off the power, a dial button for performing a dial operation during transmission, and a mode switching button for switching the operation mode of the mobile phone 100. . The mode switching button switches the operation mode of the mobile phone 100 to a call mode for making a call, a reproduction mode for displaying an image on the liquid crystal display monitor 106, and a projection display mode for projecting and displaying an image. When the projection display mode is selected, an image is projected and displayed from the projection module 105.

  FIG. 2 is a block diagram showing a schematic configuration of the projection module 105 of the mobile phone 100 according to the embodiment of the present invention. The projection module 105 of the mobile phone 100 according to the present embodiment is a device having a function of projecting image light onto a screen to display an image, and includes a projection unit 1, a correction unit 2, a video input unit 3, An operation unit 4 and a control unit 5 are provided.

  The projection unit 1 includes a projection signal processing unit 11, a light source lamp 12, a color wheel 13, a DMD (Digital Micromirror Device) 14, a projection lens 15, and a zoom lens 16.

  Specifically, the projection signal processing unit 11 generates a projection video signal based on the video data from the video input unit 3. The light source lamp 12 is, for example, a light source lamp in which white LEDs (light emitting diodes) are arranged in a matrix, or an ultra-high pressure mercury lamp, a metal halide lamp, a xenon lamp, etc., and a light source lamp with higher brightness and higher efficiency is desirable. . The color wheel 13 is a rotary divided color filter that switches the image light from the light source lamp 12 to one of R (red), G (green), and B (blue) monochromatic light. A synchronization circuit (not shown) is connected to the color wheel 13, and the rotation of the color wheel 13 is controlled by this synchronization circuit. The DMD 14 is, for example, a substantially rectangular optical device having an IC (Integrated Circuit) in which hundreds of thousands to millions of micromirrors are spread, and emits light based on video data from the video input unit 3. Image light is generated by reflection in dot units. At this time, the two states of “ON” and “OFF” can be controlled by controlling the inclination of the plurality of micromirrors. Each micromirror corresponds to one pixel of the display element. When the micromirror is “ON”, the light from the light source lamp 12 is reflected toward the outside (screen or the like) and projected onto the screen or the like through the projection lens 15. On the other hand, when the micromirror is “OFF”, the light is reflected to the internal absorber and is not projected to the outside. Therefore, the light projection can be controlled for each display pixel by individually driving each micromirror. Here, when all the micromirrors constituting the DMD 14 are “ON”, the size of the projected image is maximized, which is a so-called projectable range. On the other hand, in this embodiment, the ON / OFF state is controlled so that the projected image is projected onto a part of the projectable range. The projection lens 15 and the zoom lens 16 enlarge and project the light (optical image) modulated by the DMD 14 onto a screen or the like.

  That is, in the projection unit 1, the light emitted from the light source lamp 12 is switched to R, G, or B monochromatic light by the color wheel 13, and this monochromatic light is modulated by the DMD 14, and the modulated optical image is converted. The projection lens 15 and the zoom lens 16 are enlarged and projected onto a screen or the like.

  The direction and size of shaking of the mobile phone 100 due to camera shake is detected by the shake detection sensor 21. The shake detection sensor 21 is configured by an acceleration sensor, detects a shake of the mobile phone 100 due to a shake, and inputs a shake detection signal indicating a direction and a magnitude of the detected shake to the control unit 5.

The video input unit 3 is configured such that an external memory such as a microSD card can be attached and detached, and inputs video data of a video to be projected on a screen or the like.
The operation unit 4 has a plurality of operation keys related to ON / OFF of the apparatus power supply, dial operation during transmission, switching of operation modes, and the like, and allows operation commands from the user to be input.

The control unit 5 includes, for example, a CPU (Central Processing Unit) 51, a RAM (Random Access Memory) 52, a ROM (Read Only Memory) 53, and the like, and controls each unit of the mobile phone 100.
The CPU 51 reads the processing program stored in the ROM 53, develops it in the RAM 52, and executes it to control the entire mobile phone 100.
The RAM 52 expands the processing program executed by the CPU 51 in the program storage area in the RAM 52, and stores the input data and the processing result generated when the processing program is executed in the data storage area.
The ROM 53 is composed of, for example, a semiconductor memory and stores processing programs, data, and the like in advance. In the ROM 53, for example, a projection program 53A for projecting an image based on the image data input from the image input unit 3 onto a screen or the like, and when camera shake is detected, ON / OFF of each micromirror is controlled to detect camera shake. A correction program 53B for correction, a center movement program 53C for gently moving the projection position to the center of the projectable range, and the like are stored.

  Further, the control unit 5 tilts the mirror surface of each micromirror based on the shake detection signal from the shake detection sensor 21 so that the shake of the projected image due to the camera shake is corrected. Specifically, an LUT (Look Up Table) that associates the direction and size of camera shake due to camera shake with the ON / OFF control of each micromirror required to correct the shake of the projected image is obtained in advance. Then, based on the shake detection signal input to the control unit 5, the ON / OFF of each micromirror is controlled with reference to the LUT. As a result, even if camera shake occurs during projection display, the projection image projected and displayed on the screen or the like is not likely to be blurred and difficult to see.

  Since the projection display of the image by the mobile phone 100 is performed with the user holding the mobile phone 100 in his / her hand, the user is easily affected by vibration due to camera shake. it can.

  FIG. 3 is a flowchart showing an example of the projection display process executed by the CPU 51 of the mobile phone 100. FIG. 4 is a flowchart illustrating an example of correction processing that is executed when camera shake occurs during projection display. On the other hand, FIG. 5 is a flowchart illustrating an example of the center movement process executed when camera shake is not detected during projection display.

  In FIG. 3, after the user expands the reception unit 102 and the transmission unit 103 that are folded, the operation mode of the cellular phone 100 is switched to the projection display mode by operating the mode switching button of the operation unit 4 (step S11).

  In step S12, an image list of images read from an external memory such as a microSD card is displayed on the liquid crystal display monitor 106. Here, when the user selects an image to be projected and displayed from the image list, the image data of the selected image is read from the external memory, and the image data is acquired.

  In step S13, the light source lamp 12 is controlled to irradiate the color wheel 13 with illumination light. The monochromatic light switched by the color wheel 13 is modulated into image light by the DMD 14. The modulated image light is projected onto a screen or the like by the projection lens 15, and a projected image is displayed.

  In step S14, it is determined whether camera shake has occurred during projection display. If camera shake occurs during the projection display, the process proceeds to step S15, and correction processing is performed according to the flowchart of FIG. On the other hand, when camera shake is not detected during the projection display, the center movement process is performed according to the flowchart of FIG.

  In FIG. 4, in step S <b> 21, the shake detection sensor 21 detects a shake applied to the mobile phone 100, and a shake detection signal indicating the shake direction and magnitude is input to the control unit 5.

  In step S <b> 22, a movement amount is calculated based on the shake detection signal input to the control unit 5, and processing for controlling the tilt of the mirror surface of each micromirror is performed so that the projection position remains at b <b> 1.

  In step S23, the mirror surface of each micromirror is tilted based on the calculation result, and the projection position is corrected. With this processing, even if camera shake occurs during projection display, there is no possibility that the projected image projected and displayed on the screen or the like will be blurred and difficult to see.

  FIG. 6 is an explanatory diagram illustrating an example of an image for correcting the projection position when camera shake occurs during projection display. FIG. 6 shows a normal projectable range a1 and a projection position b1, and a projectable range a2 and a standard projection position b2 when camera shake occurs. When camera shake occurs during projection display, the projectable range moves from a1 to a2. On the other hand, since the projection position is originally set to be in the center of the projectable range, normally, the projection position should move from b1 to b2. However, if the projection position is moved from b1 to b2, the projected image will be blurred. Therefore, in the present embodiment, correction processing is performed to keep the projection position that should originally move to b2 at b1.

  As described above, in the present embodiment, even if camera shake occurs during the projection display, the shake detection sensor 21 detects the direction and size of the shake applied to the mobile phone 100, and based on the detection result, Since the blur is corrected, there is no possibility that the projected image projected and displayed on the screen or the like is blurred and difficult to see.

In FIG. 5, in step S31, it is determined whether or not the current projection position is in the center with respect to the projectable range. If the current projection position is in the center of the projectable range, it is not necessary to change the projection position, and the process ends.
On the other hand, when the current projection position deviates from the center of the projectable range, the process proceeds to step S32, and processing for bringing the projection position to the center of the projectable range is performed.

  In step S32, the center of the current projection position is compared with the center of the projectable range, and the distance and direction between the centers are calculated. Then, the projection position is calculated so that the projection position comes to the center of the projectable range.

  In step S33, a process of tilting the mirror surface of each micromirror based on the calculation result and moving the projection position to the center of the projectable range at a predetermined speed is performed. For example, in the present embodiment, the predetermined speed is a moderate speed that does not cause the user to feel the movement of the projected video. The speed setting may be left up to the user, or the speed may be set higher as the distance is longer in relation to the distance between the centers.

  FIG. 7 is an explanatory diagram illustrating an example of an image in which the projection position is moved to the center of the projectable range when the projection position is shifted from the center of the projectable range. FIG. 7A shows a case where the previous projection position b1 is within the projectable range a2 moved by camera shake. In this case, since the correction does not exceed the so-called correction limit position, the movement is gradually performed from b1 to b2. On the other hand, FIG. 7B shows a case where the previous projection position b1 does not fit within the projectable range a2 moved by camera shake. In this case, since the correction exceeds the so-called correction limit position, a process of once moving to a position c where the straight line connecting the centers of b1 and b2 and the projectable range a2 are in contact with each other and then gradually moving toward b2 is performed. Is called.

  As described above, in this embodiment, even when the projection position of the image is deviated from the center of the projectable range, the process of moving the image to the center of the projectable range at a moderate speed is performed. The correction performance can be recovered without causing the user to feel.

  As mentioned above, although concretely demonstrated based on embodiment which concerns on this invention, this invention is not limited to the said embodiment, It can change in the range which does not deviate from the summary.

  For example, in the above-described embodiment, the shake detection sensor 21 is used to detect the shake of the mobile phone 100 and the mirror surface of each micromirror is corrected based on the detection result. You may make it perform what is called optical camera-shake correction which moves a projection lens instead of inclining a mirror surface. In addition, for example, the mobile phone 100 is provided with an imaging function, and two projected images projected on a screen or the like are instantaneously captured and compared to detect blurring of the subject image so that the two subject images are the same. In other words, so-called electronic blur correction may be performed in which an effective pixel region is set so as to fit within the screen.

  Moreover, in the said embodiment, although the acceleration sensor is applied as the shake detection sensor 21, you may use an angular velocity sensor etc., for example.

  Moreover, in the said embodiment, although the mobile phone with a projection display function which incorporated the projection module was illustrated, for example, it applies to portable electronic devices, such as a digital camera, PDA, an electronic notebook, etc. which incorporated such a projection module. May be.

  Moreover, in the said embodiment, although DMD is applied to the projection module, you may apply LCD (Liquid Crystal Display), for example.

1 is an external perspective view of a mobile phone with a projection display function according to an embodiment of the present invention. It is a block diagram which shows schematic structure of the mobile telephone which is one Embodiment which concerns on this invention. It is the flowchart shown about an example of the projection display process performed by CPU of a mobile telephone. It is a flowchart which shows an example of the correction process performed when camera shake generate | occur | produces during a projection display. It is a flowchart which shows an example of the center movement process performed when camera shake is not detected during a projection display. It is explanatory drawing which shows an example of the image which correct | amends a projection position when camera shake generate | occur | produces during projection display. It is explanatory drawing which shows an example of the image which moves a projection position to the center of a projectable range when a projection position has shifted | deviated from the center of the projectable range.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projection part 11 Signal processing part for projection 12 Light source lamp 13 Color wheel 14 DMD
DESCRIPTION OF SYMBOLS 15 Projection lens 16 Zoom lens 2 Correction | amendment part 21 Shake detection sensor 3 Image | video input part 4 Operation part 5 Control part 51 CPU
52 RAM
53 ROM
DESCRIPTION OF SYMBOLS 100 Mobile telephone 101 with a projection display function Hinge part 102 Reception part 103 Transmission part 104 Telephone part 105 Projection module 106 Liquid crystal display monitor 107 Reception speaker 108 Transmission microphone

Claims (7)

Projection means for projecting image light onto a part of the projectable range via a projection lens;
A shake detection means for detecting the direction and size of the shake generated during projection of the video by the projection means;
Control means for controlling the projection position of the image projected and displayed by the projection means,
The control means includes
Based on the detection result of the blur detection means, the blur of the projected video is corrected, and after the correction is made, if the projected position of the video is deviated from the center of the projectable range, the projected position can be projected. A projection-type image display device, wherein the projection-type image display device is moved to the center of the range at a predetermined speed.   The control means compares the center of the projection position with the center of the projectable range, calculates the distance and direction between the centers, and moves the projection position to the center of the projectable range based on the calculation result. The projection type image display apparatus according to claim 1, wherein the projection type image display apparatus is moved at a predetermined speed.   The control unit projects the projection image at a position that falls within the projectable range when the blur of the projection image cannot be corrected within the projectable range based on the detection result of the blur detection unit. The projection type image display apparatus according to claim 1 or 2.   The projection type image display apparatus according to any one of claims 1 to 3, wherein the blur detection unit includes an acceleration sensor that detects a direction and a magnitude of the blur. The projection means includes a light source composed of LEDs and a DMD composed of a plurality of micromirrors,
5. The control unit according to claim 1, wherein the control unit causes the projection image to be projected onto a part of the projectable range by controlling the inclination of the plurality of micromirrors. 6. Projection-type image display device. A light source configured by an LED and a DMD configured by a plurality of micromirrors, and by controlling the inclination of the plurality of micromirrors, a part of a range in which image light can be projected through a projection lens Projection means for projecting to
An acceleration sensor that detects a direction and a size of a shake that is generated when an image is projected and displayed by the projection unit;
Control means for controlling the projection position of the image projected and displayed by the projection means,
The control means includes
While correcting the blur of the projected image based on the detection result of the acceleration sensor,
When the blur of the projected video cannot be corrected within the projectable range based on the detection result of the blur detection unit, the projected video is projected at a position that falls within the projectable range,
After the correction is made, if the projected position of the image is shifted from the center of the projectable range, the center of the projected position is compared with the center of the projectable range, and the distance and direction between the centers are calculated. A projection-type image display apparatus that moves the projection position to the center of the projectable range at a predetermined speed based on the calculation result.   A portable electronic device comprising the projection display apparatus according to claim 1.

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