JP4153361B2 - Image display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image display device, and more particularly to an image display device that is used in a portable or vehicle-mounted electronic device and can easily display an image even in an environment with vibration or shaking.
[0002]
[Prior art]
Many portable electronic devices use small display devices. FIG. 5 shows an example of a portable electronic device using such a display device. 5A shows a portable video recorder provided with a display device 57 and a camera 59, FIG. 5B shows a mobile phone provided with a display device 61 and a camera 63, and FIG. A portable information terminal referred to as a so-called PDA (Portable Digital Assistant) including a display unit 65 and a camera 67 is shown. Many of these portable electronic devices are each provided with a relatively small and low-resolution display device, and are observed in a state relatively close to the eyes. For this reason, when these display devices are carried by humans or used on vehicles, it has not been a big problem even if the image is somewhat difficult to see due to shaking or vibration.
[0003]
Conventionally, in order to make it easy to see an image in an image display device used in an environment with vibration, a device using a gyro sensor, a magnetic sensor, or the like has been proposed. See JP-A 09-009179 and JP-A 10-069266.
[0004]
[Problems to be solved by the invention]
However, due to recent technological advances, relatively large and high-resolution display devices (displays) have come to be used also in portable or in-vehicle electronic devices. When such a relatively large and high-resolution display device is used in an environment with vibrations, it is difficult to accurately grasp the display content displayed on the screen of the display device, and the screen is very difficult to see. There was an inconvenience. Further, in the case of using a gyro sensor or the like to correct the shake of the display device, it is necessary to use a special sensor or the like, which has a disadvantage that the device configuration becomes complicated.
[0005]
Therefore, in view of the problems in the prior art, the object of the present invention is that a display device used in an environment with shaking or vibration has a large display screen with a large display screen with a simple device configuration. However, an easy-to-see display screen can be provided.
[0006]
[Means for Solving the Problems]
According to an aspect of the present invention, there is provided an image display device including an image memory that receives and temporarily stores image data to be displayed, and a display unit that displays an image based on read data from the image memory. Is an imaging unit that captures an image of an object at a fixed position with respect to an observer of the image display device or an observer of the image display device, and the display unit based on imaging data of the imaging unit And a movement vector calculation unit for calculating a movement vector indicating a relative movement amount and direction between the observer, an address control unit for controlling a read address of the image memory based on the movement vector from the movement vector calculation unit, It is characterized by comprising.
[0007]
Conveniently, the imaging unit is integrated with the display unit.
[0008]
Alternatively, it may be configured to include a level attached in front of the imaging lens of the imaging unit.
[0009]
In this case, the moving vector can be obtained by imaging the bubble of the level with the imaging unit.
[0010]
In addition, the imaging unit can be configured to image the observer's head of the display device.
[0011]
In this case, it is convenient that the observer's head is a part including the eyes of the observer.
[0012]
The imaging unit can also capture an image of an object fixed with respect to the ground where the observer is located.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a configuration of an image display apparatus provided with image stabilization or deviation correction means according to an embodiment of the present invention, and how a user observes such an image display apparatus. In FIG. 1, the image display device is indicated by reference numeral 1 and is configured as a portable electronic device. The image display device 1 generally includes a display unit 3 and a camera 5 attached to or integrated with the display unit 3. Note that the display device 1 is provided with an electronic circuit or the like necessary for a portable electronic device inside the display unit 3 or the like.
[0014]
In the image display device 1 of FIG. 1, image information necessary for the function of the image display device 1 is displayed on the display unit 3. The image display device 1 is held by a user, that is, an observer 7, and the screen of the display unit 3 is observed by the eyes 9 of the observer 7.
[0015]
Assume that the observer 7 is located on the ground 11, for example. In this case, the camera 5 of the image display device 1 captures the check pattern A (reference numeral 13) at the ground 11 or a position fixed with respect to the ground 11. The check pattern A can be, for example, an arbitrary object, pattern or other image on the ground 11.
[0016]
In such a situation, the image display device 1 held by the observer 7 is shaken or vibrated as schematically shown by the reference numerals 1a and 1b by the movement of the observer 7's hand, for example. Consider. In such a case, the image display device 1, and hence its display unit 3, also shakes or vibrates with respect to the eyes 9 of the observer 7. For this reason, it is difficult to see the image displayed on the display unit 3 and it is difficult to grasp the display contents. In particular, when the image displayed by the display unit 3 is a high-resolution image, the display image is difficult to see.
[0017]
In the present invention, in order to make it easy to see the display image and accurately grasp the display contents in such a case, the display image is made easy to see by the following method. That is, the check pattern A is imaged continuously or at predetermined time intervals by the camera 5. Thereby, data indicating the moving direction and moving amount of the check pattern A with respect to the camera 5, that is, a moving vector is obtained. And the position of the image displayed on the display part 3 is moved based on this movement vector.
[0018]
For example, in FIG. 1, assuming that the camera 5 has moved in the direction of the arrow, the check pattern A captured by the camera 5 moves as indicated by the movement vector indicated by reference numeral 15. The position of the image or character B displayed on the screen of the display unit 3 is moved in the direction of the arrow according to the movement vector obtained by such movement of the check pattern A, and the image B and the eye 9 of the observer 7 are moved. Eliminate or reduce relative movement. As a result, as indicated by reference numeral 19, even if the image display device 1 held by the observer 7 vibrates or shakes with respect to the eyes 9 of the observer 7, the eyes 9 of the observer 7 are displayed. Relative vibration or shaking with the display image displayed on the unit 3 is eliminated or extremely reduced. Therefore, for the observer 7, the images or characters displayed on the display unit 3 of the image display device 1 are very easy to see, and the display contents can be accurately grasped.
[0019]
FIG. 2 shows a schematic configuration of a portable electronic device provided with an image display device according to another embodiment of the present invention. As shown in FIG. 2A, the image display device 21 according to this embodiment includes a display unit 23 and a camera 25 attached to the display unit 23. The device 21 is held in the hand of the observer 7, and the display screen of the display unit 23 is observed by the eyes 9 of the observer 7. Reference numerals 21a and 21b schematically indicate that the device 21 held in the hand of the observer 7 vibrates or shakes.
[0020]
FIG. 2A shows a detailed configuration example of the camera 25 portion of the image display apparatus 21 according to this embodiment. The camera 25 includes a camera head 27 and a level 29 that is imaged by the camera head 27. Therefore, for example, the camera head 27 includes a wide angle macro lens (not shown), and a level 29 is disposed in front of the wide angle macro lens. The level 29 is configured by enclosing water or other liquid 29a in a sealed container 29c, and the liquid 29a is provided with bubbles 29b. The liquid 29a may be colored or the like as necessary in order to make the image of the bubbles 29b imaged by the camera head 27 clear.
[0021]
In the image display device shown in FIGS. 2 (a) and 2 (b), the bubble 29b of the level 29 is always located at the top of the sealed container 29c even if the device 21 moves or vibrates slightly, It remains in a fixed position relative to the ground. Therefore, by capturing an image of the bubble 29b of the level 29 with the camera 25, a movement vector indicating the movement state of the device 21 with respect to the ground, for example, can be obtained. Accordingly, by correcting the position of the image displayed on the display unit 23 using the movement vector information, the relative movement between the image displayed on the display unit 23 and the eyes 9 of the observer 7 is changed. It can be lost or reduced. Thereby, the observer 7 can easily see the display image and can accurately grasp the display contents.
[0022]
FIG. 3 shows a schematic configuration of a display device according to still another embodiment of the present invention. The display device 31 according to this embodiment is an in-vehicle navigation system mounted on a vehicle such as an automobile. The display device 31 includes a display unit 33 and a camera 35 fixed to the display unit 33. The display device 31 according to this embodiment is attached to a vehicle. In FIG. 3, the display device 31 is attached to the bearing portion of the handle 37, but can be attached to any location on the vehicle.
[0023]
In this embodiment, the camera 35 of the display device 31 is disposed so as to capture an image of the driver 9 of the vehicle as the observer 7 or an image of the head 9 a including the eyes 9. The camera 35 may image a portion that moves substantially the same as the eyes 9 other than the eyes 9 of the observer 7. In this embodiment, when the display device 31 moves relative to the observer 7 by driving the vehicle such as the observer 7, an image position such as the eye 9 of the observer 7 captured by the camera 35. Move to obtain a movement vector. By controlling the display position of the image displayed on the display unit 33 based on this movement vector, it is possible to compensate for the relative deviation between the observer 7 and the image displayed on the display unit 33, so that the display image is easy to see. And the contents can be easily grasped. Reference numerals 31 a and 31 b schematically show how the display device 31 moves with respect to the observer 7.
[0024]
FIG. 4 shows a schematic configuration of an electric circuit portion that can be used in the display device according to the present invention. 4 includes a movement correction unit 41 that detects a movement vector and corrects a display image, and a display unit that includes a display unit 53 that displays an image based on input image data, for example, RGB or YUV data. Consists of.
[0025]
The movement correction unit 41 includes a camera 47 that is integrated with or attached to the display unit 53. The camera 47 that is originally provided in the display device may be used, or a new camera 47 may be provided to correct vibration or shaking. The movement correction unit 41 further includes a memory 43 that temporarily stores image data obtained by the camera 47, a movement vector calculation unit 45, and a read address control unit 49. The movement vector calculation unit 45 obtains a signal indicating a movement vector using the image data stored in the memory 43 or the image data stored in the memory 43 and the image data output from the camera 47. The movement vector is a parameter indicating a relative movement direction and a movement amount between the display device and the observer's head obtained from image data captured by the camera 47. Therefore, in order to obtain the movement vector, the camera may be installed on the display device side or on the viewer's head side.
[0026]
Therefore, for example, in order to measure how the display device vibrates when viewed from the observer's head, the camera should be fixed on the display device side and the head or eyes should be vibrated. That is, it is sufficient to detect motion. In this case, for example, a camera having a viewing angle of about 46 degrees can be used. Further, as an example, the movement vector calculation unit 45 calculates how many pixels the image has moved in each of the horizontal and vertical directions in one frame = 1/60 seconds. Therefore, based on data captured by the camera 47 and / or data stored in the memory 43, it is possible to calculate how many pixels and in which direction each frame has moved.
[0027]
Data indicating such a movement vector is supplied from the movement vector calculation unit 45 to the read address control unit 49. Based on such movement vector data, the read address control unit 49 creates read address control data to control the read address of the image data stored in the image memory (memory 55) on the display device side, and performs memory control. Supplied to the unit 51.
[0028]
On the display device side, normally, input image data (RGB / YUV) is temporarily stored in the image memory 55 under the control of the memory control unit 51. Based on the image data read from the image memory 55, the display unit 53 displays an image. The memory control unit 51 includes a display device 51a called a normal RAMDAC including a random access memory (RAM) and a D / A converter (DAC). The RAMDAC 51 a is a device for converting digital data stored in the image memory 55 into an analog signal so that it can be displayed on the display unit 53.
[0029]
Movement correction data, that is, read address control data is input from the read address control unit 49 on the movement correction unit 41 side to the memory control unit 51 on the display device side as described above. This read address control data is, for example, a display position of an image displayed on the display screen of the display unit 53 by controlling the read start address of the image data from the image memory 55 according to the value of the movement vector. Control to be fixed with respect to the eyes.
[0030]
Further, when the time difference between the detection of the movement vector and the display on the display unit is significant, “motion prediction” may be performed. In this case, acceleration, that is, a change in motion is also required as a parameter of the movement vector. The unit of acceleration can be, for example, pixels per second. In this case, for example, data “how many pixels are expected to move in the horizontal and vertical directions” can be predicted from the past data after the movement vector is detected and before the image position is corrected. . This makes it possible to correct more accurately for various relative movement modes between the display device and the observer.
[0031]
As another application example of the present invention, the present invention can be applied to shake correction of a large display beside a railroad track viewed from a swinging train. For example, by installing a camera on the side of such a display, detecting the shaking of the train with this camera, and correcting the image displayed on the display, the passenger on the train can see the display image without shaking. It becomes possible.
[0032]
【The invention's effect】
As is clear from the above, according to the present invention, by using the camera provided in the display device, the display device is easy to see even if the display device is used in an environment with shaking or vibration by a simple device configuration. Can be provided. Further, even if the display screen of the display device is large and has a high resolution, it is possible to accurately correct the blur of the display image, and to accurately grasp the display contents.
[0033]
Further, when the image display device is, for example, a portable display device and originally provided with a camera, it is possible to perform blurring correction of the display image using image data obtained by the camera. Also in this case, it is possible to perform blurring correction of a display image with a simple device configuration without using a special device such as a gyro sensor.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing a configuration and a usage state of an image display apparatus according to an embodiment of the present invention.
2A and 2B are explanatory views showing an image display device according to another embodiment of the present invention, in which FIG. 2A shows the configuration and use state of the image display device, and FIG. 2B shows the camera part of the image display device; Details are shown.
FIG. 3 is an explanatory diagram showing a configuration and a usage state of an image display device according to still another embodiment of the present invention.
FIG. 4 is a block diagram showing an example of a circuit configuration of an image display apparatus according to the present invention.
FIG. 5 is an explanatory diagram showing an example of a conventional portable electronic device including an image display device.
[Explanation of symbols]
1, 21, 31 Image display device 3, 23, 33 Display unit 5, 25, 35 Camera unit 7 Observer 9 Observer eye 11 Ground 27 Camera head 29 Level 37 Handle 41 Movement correction unit 43 Image memory 45 Movement vector Calculation unit 47 Camera unit 49 Read address control unit 51 Memory control unit 53 Display unit 55 Image memory

Claims (7)

An image display device comprising: an image memory that receives and temporarily stores image data to be displayed; and a display unit that displays an image based on read data from the image memory,
An imaging unit that captures an image of an object at a fixed position with respect to at least a part of an observer of the image display device or an observer of the image display device;
A movement vector calculation unit that calculates a movement vector indicating a relative movement amount and direction between the display unit and the observer based on imaging data of the imaging unit;
An address control unit that controls a read address of the image memory based on a movement vector from the movement vector calculation unit;
An image display device comprising: The image display apparatus according to claim 1, wherein the imaging unit is integrated with the display unit. The image display device according to claim 1, further comprising a level attached in front of an imaging lens of the imaging unit. The image display apparatus according to claim 3, wherein a moving vector is obtained by imaging the bubble of the level with the imaging unit. The image display device according to claim 1, wherein the imaging unit images an observer's head of the display device. The image display apparatus according to claim 5, wherein the observer's head is a part including the eyes of the observer. The image display apparatus according to claim 1, wherein the imaging unit captures an image of an object fixed with respect to a ground on which the observer is positioned.

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