JP2014224841A - Video projection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a video projection system that can adjust projection images to desired sizes without requiring a high-performance imaging device.SOLUTION: The present invention includes an optical sensor and a video projection device 4. The video projection device 4 projects a projection video 2 on a projection surface 3 including optical sensors. A projection unit 25 projects test signals on the projection video 2. An acquisition unit 20 acquires response signals to the test signals. A detection unit 21 detects positions of the optical sensors on the projection video 2. Adjustment units (zoom unit 22, and lens shift unit 23) adjust the size of the projection video 2 according to the positions of the optical sensors.

Description

  The present invention relates to a video projection system, and more particularly to a video projection system having a function of adjusting the size of a projected video.

  In recent years, video projection systems including a video projection device that projects a video on a screen (projection surface) have become widespread in meetings, educational sites, streets, homes, and the like. By using this video projection system, it becomes easy to view video on a large screen.

  Furthermore, by installing an optical zoom function, a geometric distortion correction function, or the like in the video projection device, it is possible to project the video in a size (including shape) desired by the viewer and appreciate the video.

  For example, in the video projection systems disclosed in Patent Documents 1 to 3, a projected image is captured in a range including the projected video and the projection plane, and the projected image is analyzed by analyzing the captured image. ).

Japanese Patent Laid-Open No. 8-292396 JP 2004-260785 A JP 2006-201673 A

  In the above-described video projection system, the image of the range including the projection video and the projection plane captured by the imaging device is analyzed, and the size of the projection video projected on the projection plane is automatically adjusted.

  In such a video projection system, it is necessary to first capture a projected image and a range of images including the projection plane using the imaging device, so that the projected video and the projection plane are within the range that can be captured by the imaging device. There must be.

  On the other hand, for example, when viewing a large screen image, the distance between the image projection device equipped with the image pickup device and the projection surface becomes long in order to ensure a wide image pickup range. The longer the distance between the two, the lower the projected image and the resolution of the projection plane in the obtained image. Therefore, in order to analyze the obtained image and grasp the positional relationship between the projection plane and the projected image, there has been a problem that an imaging device capable of capturing an image with a higher resolution is required.

  The present invention has been made to solve the above-described problems. Even when the distance between the image projection device and the projection surface is long, a high-performance imaging device is not required and projection is performed. An object of the present invention is to provide an image projection system capable of adjusting an image to a desired size.

  An image projection system according to an aspect of the present invention includes three or more sensors that are detachably disposed on a projection surface, and an image projection device that projects a projection image on a projection surface including the three or more sensors. The image projection device includes: a projection unit that projects a test signal on the projection image; an acquisition unit that acquires a response signal output from each sensor in response to the test signal; and And a detection unit that detects a position of each sensor on the projection image, and an adjustment unit that adjusts the size of the projection image in accordance with the detected position of each sensor.

  According to the above aspect of the present invention, the size based on the position of the sensor on the projected image is projected based on the response signal from the sensor arranged in the projected image by projecting the test signal on the actually projected image. Therefore, the projected image can be adjusted to the size desired by the viewer regardless of the distance between the image projection device and the projection plane.

It is a figure which shows the structure of the video projection system regarding 1st Embodiment. It is a figure which shows the functional structure of the image projection apparatus regarding 1st Embodiment. It is a figure which shows the test signal for optical sensor position detection. It is a figure which shows the test signal for optical sensor position detection. It is a figure which shows the coordinate which digitizes the position of the detected optical sensor. It is a figure which shows the structure of the video projection system regarding 2nd Embodiment. It is a figure which shows the coordinate which digitizes the position of the detected optical sensor. It is a figure which shows the structure of the video projection system regarding a base technology.

  Hereinafter, embodiments will be described with reference to the accompanying drawings.

  FIG. 8 is a diagram showing a configuration of a video projection system related to the base technology.

  As shown in FIG. 8, the video projection system includes a video projection device 40 and an imaging device 5.

  The imaging device 5 captures the projected video and the image of the projection plane 3. The video projection device 40 analyzes the image captured by the imaging device 5 and automatically adjusts the video size of the projection video 2 projected on the projection plane 3.

  In such a video projection system, since it is necessary to first capture an image in a range including the projected video and the projection plane using the imaging device 5, the projection video and the projection plane are within the range that the imaging device 5 can capture. Must be in place.

  On the other hand, for example, when viewing a large-screen image, the distance between the image projection device 40 including the image capture device 5 and the projection plane 3 is increased in order to ensure a wide image capture range. The longer the distance between 40 and the projection plane 3, the lower the projected image in the obtained image and the resolution of the projection plane 3. Therefore, in order to analyze the obtained image and grasp the positional relationship between the projection surface 3 and the projected image, there has been a problem that an imaging device capable of capturing an image with a higher resolution is required.

  The embodiment described below relates to an image display apparatus that solves the above-described problems.

<First Embodiment>
<Configuration>
FIG. 1 is a diagram illustrating a configuration of a video projection system according to the first embodiment.

  As shown in FIG. 1, the image projection system includes an optical sensor 11, an optical sensor 12, an optical sensor 13, an optical sensor 14, and an image projection device 4 that are detachably disposed on the projection surface 3. In addition, you may comprise including the element which is not illustrated here.

  The optical sensors 11 to 14 are detachably disposed on the projection plane 3. The arrangement is made, for example, in such a manner that a quadrangular surface having sides parallel to the respective sides of the projection surface 3 is cut, that is, arranged in the four corners of such a quadrilateral. The area surrounded by the optical sensors 11 to 14 corresponds to the size of the projection image desired by the viewer, and the projection image 2 is projected from the image projection device 4 in the projection range surrounded by the optical sensors 11 to 14. .

  The optical sensors 11 to 14 detect light and output the detected information. In the present embodiment, four photosensors are arranged. However, the invention can be applied to three or more photosensors because a desired projection range described later can be defined.

  FIG. 2 is a diagram showing a functional configuration of the video projection device 4.

  As illustrated in FIG. 2, the video projection device 4 includes an acquisition unit 20 that acquires information obtained by the optical sensors 11 to 14 and a detection unit 21 that detects the positions of the optical sensors 11 to 14 based on the acquired information. A zoom unit 22 that executes optical zoom (changes the focal length), a lens shift unit 23 that executes lens shift (correction according to the arrangement of the image projection apparatus with respect to the projection plane), and geometric distortion correction. A geometric distortion correction unit 24 to be executed and a projection unit 25 to project a test signal are provided. Among them, the zoom unit 22, the lens shift unit 23, and the geometric distortion correction unit 24 can be collectively used as an adjustment unit. The geometric distortion correction unit 24 may not be provided.

  These functions are realized by the CPU performing program processing based on software and controlling the control target.

  In addition, these functional units are illustrated as being mounted in the image projection device 4 in FIG. 2, but are conceptually provided by interacting with other functional units that are external functional units. Alternatively, it may function as a configuration in the video projection device 4.

<Operation>
First, the position of the projected image 2 is adjusted so that the optical sensors 11 to 14 arranged on the projection surface 3 are located inside the projected image 2 (within the projection range). Specifically, the zoom unit 22 of the image projection device 4 sets the zoom value to the maximum by the optical zoom function, and the lens shift unit 23 of the image projection device 4 adjusts the position of the projection image 2 by the lens shift function. To do. The zoom value does not necessarily have to be set to the maximum.

  Next, the projection unit 25 of the image projection device 4 projects a test signal (FIG. 3) for detecting the positions of the optical sensors 11 to 14 onto the projection image 2. The test signal is projected corresponding to each vertical line (white) with a width of 1 dot, and the projection destination is moved in the horizontal direction in the projected image 2 in time sequence (sequentially along the time axis). At that time, information detected by the optical sensors 11 to 14 is transmitted to the acquisition unit 20 of the video projection device 4 as a response signal. The transmission may be transmission via a wire or transmission by wireless communication.

  And the detection part 21 of the image projection apparatus 4 detects the position of the horizontal direction of the optical sensors 11-14 by comparing a response signal and the input signal of a test signal. Specifically, the timing at which the response signal is output is compared with the timing at which the test signal is projected, and the test signal at the time when the optical sensors 11 to 14 detect the test signal in the horizontal direction of the projection destination line. Detect position.

  Thereafter, projection is performed for each horizontal line (white) having a width of 1 dot (FIG. 4), and the projection destination is moved in the vertical direction in the projection image 2 in time order (sequentially along the time axis). At that time, information detected by the optical sensors 11 to 14 is transmitted to the acquisition unit 20 of the video projection device 4 as a response signal. The transmission may be transmission via a wire or transmission by wireless communication.

  And the detection part 21 of the image projection apparatus 4 detects the position of the vertical direction of the optical sensors 11-14 by comparing a response signal and the input signal of a test signal.

  Note that the above-mentioned “vertical” and “horizontal” are directions used for the sake of convenience, and do not necessarily coincide with the actual directions. The test signal projection method is not limited to the above method. For example, when different signals are simultaneously projected for each dot, and response signals that can identify each dot are transmitted from the optical sensors 11 to 14. It may be.

  FIG. 5 is a diagram showing coordinates for digitizing the position of the detected optical sensor. Here, the coordinate axes of the x axis and the y axis are taken as shown in FIG.

  Let the upper left corner of the projected image 2 be (0, 0) and the lower right corner be (X, Y). X and Y correspond to the number of pixels in the horizontal and vertical directions of the display device mounted on the video projector 4. The positions of the optical sensors 11 to 14 detected as described above can be expressed as (x1, y1), (x2, y2), (x3, y3), and (x4, y4) as coordinate points, respectively. .

  In addition, the coordinate value of each said optical sensor 11-14 may be the coordinate of the light-receiving part (not shown) of an optical sensor, and when a light-receiving part is detected with a specific area, The coordinates corresponding to the center position may be used.

  Each coordinate value acquired as described above indicates the size desired by the viewer for the projected image (horizontal X and vertical Y) when the zoom value is maximized. Therefore, it is possible to obtain a reduction ratio and a center point position of a desired size with respect to a projection image whose horizontal is X and vertical is Y, and the projection image 2 can be adjusted to a desired size in the adjustment unit.

<Effect>
According to this embodiment, the video projection system includes three or more sensors (photosensors 11 to 14) and the video projection device 4.

  The optical sensors 11 to 14 are detachably disposed on the projection plane 3. The image projection device 4 projects the projection image 2 on the projection surface 3 including three or more optical sensors.

  The video projection device 4 includes a projection unit 25, an acquisition unit 20, a detection unit 21, and an adjustment unit.

  The projection unit 25 projects a test signal on the projected image 2.

  The acquisition part 20 acquires the response signal output from each optical sensor 11-14 in response to a test signal.

  The detection unit 21 detects the position of each of the optical sensors 11 to 14 on the projection image 2 based on the response signal.

  The adjustment unit corresponds to the zoom unit 22 and the lens shift unit 23 and adjusts the size of the projected image 2 in accordance with the detected positions of the optical sensors 11 to 14.

  According to such a configuration, the test signal is projected onto the actually projected projection image 2, and the sensor position on the projection image 2 is determined based on the response signal from the sensor arranged in the projection image 2. Therefore, the projection image 2 can be adjusted to a size desired by the viewer regardless of the distance between the image projection device 4 and the projection plane 3.

Second Embodiment
FIG. 6 is a diagram illustrating a configuration of a video projection system according to the second embodiment. FIG. 6 shows a case where the projection image 2 from the image projection device 4 is projected from an oblique direction with respect to the projection plane 3. In the following, an example in which the projected image 2 is projected obliquely from below on the projection surface 3 will be described. In this case, the projected image 2 is a trapezoid having a short lower side and a long upper side.

  FIG. 7 is a diagram showing coordinates for digitizing the position of the detected optical sensor. Here, as shown in FIG. 7, the coordinate axes of the x axis and the y axis are taken. Since the position detection of the optical sensors 11 to 14 arranged on the projection surface 3 is the same as the method shown in the first embodiment, detailed description thereof is omitted.

  Let the upper left corner of the projected image 2 be (0, 0) and the lower right corner be (X, Y). X and Y correspond to the number of pixels in the horizontal and vertical directions of the display device mounted on the video projector 4. The positions of the optical sensors 11 to 14 detected as described above can be expressed as (x1, y1), (x2, y2), (x3, y3), and (x4, y4) as coordinate points, respectively. .

  In the present embodiment, since the shape of the projected image 2 is a trapezoid, when the trapezoid is converted into a rectangle so as to match the XY coordinate system, the positions of the optical sensors 11 to 14 in the XY coordinate system are on the projection plane 3. Unlike the actual positions of the optical sensors 11 to 14, it looks like a trapezoidal shape.

  Each acquired coordinate value (position that looks like a trapezoidal shape in the XY coordinate system) indicates the size desired by the viewer for the projected image (horizontal is X and vertical is Y) when the zoom value is maximized. Accordingly, the reduction ratio of the desired size, the position of the center point, and the geometric correction value are obtained for the projected image with the horizontal X and the vertical Y, and the projected image 2 is adjusted to the desired size (including shape). be able to.

  In the present embodiment in which the projected image 2 is projected from an oblique direction with respect to the projection plane 2, the geometric distortion correction unit 24 is aligned with the positions of the optical sensors 11 to 14 that appear at the respective vertex positions of the trapezoid in the XY coordinate system. Thus, by adjusting the shape of the projected image 2, the projected image 2 converted into, for example, a rectangle can be projected on the projection surface 2.

<Effect>
According to the present embodiment, the adjustment unit includes the geometric distortion correction unit 24, and the geometric distortion correction unit 24 adjusts the shape of the projection image 2 according to the detected positions of the respective optical sensors 11 to 14. To do.

  According to such a configuration, the test signal is projected onto the actually projected projection image 2, and the sensor position on the projection image 2 is determined based on the response signal from the sensor arranged in the projection image 2. Therefore, the projected image 2 can be adjusted to the size desired by the viewer regardless of the distance between the image projection device 4 and the projection surface 3, their positional relationship, and the projection angle. . Therefore, even a projected image projected obliquely can be adjusted to a size (including shape) desired by the viewer.

  In addition, within the scope of the present invention, the present invention can be freely combined with each embodiment, modified with any component in each embodiment, or omitted with any component in each embodiment.

  2 projection image, 3 projection surface, 4,40 image projection device, 5 imaging device, 11-14 photosensor, 20 acquisition unit, 21 detection unit, 22 zoom unit, 23 lens shift unit, 24 geometric distortion correction unit, 25 Projector.

Claims (5)

Three or more sensors each detachably arranged on the projection surface;
An image projection device for projecting a projection image on a projection plane including three or more sensors,
The image projection device
A projection unit that projects a test signal on the projected image;
An acquisition unit for acquiring a response signal output from each of the sensors in response to the test signal;
A detection unit that detects a position of each of the sensors on the projected image based on the response signal;
An adjustment unit that adjusts the size of the projected image in accordance with the detected position of each sensor;
Video projection system. The detection unit detects the position of each sensor on the projected image based on the timing at which the response signal is output.
The image projection system according to claim 1. The detection unit detects a position of each sensor on the projected image based on a timing at which the test signal is projected matches a timing at which the response signal is output. And
The video projection system according to claim 2. The projection unit projects the test signal in a time sequential manner onto a partial area on a projected image,
The video projection system according to claim 1. The adjusting unit includes a geometric distortion correcting unit;
The geometric distortion correction unit adjusts the shape of the projected image according to the detected position of each sensor,
The video projection system according to claim 1.

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