JP2003076494A - Coordinate input device for projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coordinate input device for a projector with operational inconvenience eliminated by adding a function of optical image input. SOLUTION: The coordinate input device consists of a display element 2 for receiving light from a light source and outputting an image, a spectroscope 5 for passing the image from the display element 2, a zoom optical system 3 for optically zooming in the image from the spectroscope 5, a screen for displaying the image from the zoom optical system 3, an imaging element 2 which, through the spectroscope 5, fetches an image on the screen after zoomed out by the zoom optical system 3, a laser pointer 7 for displaying by a pointer an expected position on the screen, and a difference extraction and arithmetic part. The difference extraction and arithmetic part compares the image from the display device 2 with the image from the imaging element 2, extracts the difference, identifies the absolute coordinate of the pointer display on the screen, and outputs to a coordinate output part which transforms the absolute coordinate into a relative coordinate and makes signal conversion to fit the personal computer interface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate input device for a projector, and more particularly to a coordinate input device used when a pointer is displayed on a screen by a laser pointer in a presentation or the like.

[0002]

2. Description of the Related Art Generally, a projection display device includes a rear projection TV type in which a projection tube and a screen are arranged in one housing, and a projector type in which the projection tube and the screen are separated and a screen is separately prepared. Exists.

In the latter type of projector in which the projection tube and the screen are separated and the screen is separately prepared,
As a method of inputting coordinates to a personal computer and a projector used for presentations, etc., a method in which a sensor is spread over the entire screen to make this a huge coordinate input device, and a coordinate input device of the personal computer connected to the projector itself uses radio waves and infrared rays. A typical method is remote control by wire or the like and display.

[0004]

However, in the former method, the screen itself becomes very expensive,
Various maintenance (storage, operation, inspection) will also be very difficult. Also, in the latter method,
If the coordinate is not input while considering the direction, there is a usability that the pointer moves in a different direction.

Therefore, the present invention provides a coordinate input device for a projector in which a screen is separately prepared and projected onto the screen by adding an optical image input function to the projector, thereby eliminating the inconvenience. is there.

[0006]

According to the present invention, there is provided a coordinate input device for use in a projector for projecting an image from a projection tube onto a screen provided separately, the display being capable of receiving light from a light source and outputting the image. Element 2, spectroscope 5 that allows the image from display element 2 to pass through, enlargement / reduction optical system 3 that optically enlarges the image from spectroscope 5, and screen that displays the image of enlargement / reduction optical system 3. An image pickup element 2 that reduces an image on the screen by an enlargement / reduction optical system 3 and captures it via a spectroscope 5, a light beam type pointer (laser pointer) 7 for displaying a desired position on the screen as a pointer,
The image from the display element 2 and the image pickup from the image pickup element 2 are compared to extract the difference, the absolute coordinates of the pointer display on the screen are specified, the absolute coordinates are converted into relative coordinates, and the result is output to the coordinate output section of the personal computer. And a difference extraction / calculation unit.

As a preferred embodiment, the difference extracting / calculating section 8 is provided with a display image storage area 81 for storing an image from a display element that has received an image input, a screen, an enlarging / reducing optical system, and a spectroscope. An image capturing storage area 82 for capturing an image captured via the image sensor, a comparison calculator 83 for capturing an image in the display image storage area and an image in the image capturing storage area for extracting a difference and specifying an absolute coordinate, and a separate coordinate storage. A coordinate system converter 85 is provided for converting the absolute coordinates to the relative coordinates by taking the difference between the coordinates stored in the area 84 and the absolute coordinates from the comparison operator.

As a further preferred embodiment, it is possible to directly output the absolute coordinates from the comparison calculator to the coordinate input section of the personal computer without converting the absolute coordinates into relative coordinates by the coordinate system converter.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a principle diagram of an optical system of a general projector. In this example, an image on the projector is projected from a light source on a screen by a magnifying optical system including a combination of lenses and mirrors (not shown) to form a magnified image. In this type, the user views the screen from the projector side. In this example,
Since the case where a non-self-luminous element such as liquid crystal is used is shown, the position of the light source is far from the position of the image, but when a self-luminous element (not shown) is used, the position of the light source and the image are integrated. Has become.

FIG. 2 is a principle diagram when a subject is photographed by a general camera or the like. In this case, the image of the subject
An image of a subject is reduced by a reduction optical system including a combination of lenses and mirrors (not shown), and is formed on an image sensor.

FIG. 3 is a block diagram of a coordinate input device for a projector according to the present invention. The present invention is based on the principle configuration of FIG. 1 and FIG. 2 and performs image input with the configuration of FIG. In the figure, 1 is a light source, 2 is a display element, 3 is an enlarging / reducing optical system, 4 is a screen, 5 is a spectroscope, 6 is an image pickup element, 7 is a laser pointer, and 8 is a difference extracting / calculating section.

First, in the magnifying optical system shown in FIG.
The image displayed on the display element 2 by the light from the screen passes through the spectroscope 5 and the screen 4 through the enlargement / reduction display system 3.
It is enlarged and displayed. On the other hand, in the reduction optical system of FIG.
The image on the screen 4 is taken into the image pickup device 6 via the enlargement / reduction optical system 3 and the spectroscope 5.

As the function of the spectroscope 5 in FIG. 3, the information of the magnifying optical system, that is, the data (light) on the projection side passes through, and the information of the reducing optical system, that is, the data (light) on the photographing side is reflected. A half mirror function is required. Here, the captured image captured by the image sensor 6 is an actual image actually displayed on the screen 4.

For example, when the pointer is displayed on the screen 4 by the laser pointer 7, only the portion where the pointer is displayed should be different from the original display image (see FIG. 4).

FIG. 4 is an explanatory view of the position determination on the screen of the present invention. In order to extract the above-mentioned pointer-displayed portion, the difference extraction / calculation unit 8 compares the original image with the actual display image, calculates the difference, and specifies the coordinates P of the pointer-displayed place. As will be described later, the function as a coordinate input device can be realized by transferring this coordinate data to a personal computer. Further, it is possible to assign the blinking operation of the pointer to the operation of the existing input device such as click / tap.

FIG. 5 is a detailed block diagram of the difference extracting / calculating section shown in FIG. In the figure, 81 is a display image storage area,
Reference numeral 82 is an imaging storage area, 83 is a comparison calculator, 84 is a coordinate storage area, and 85 is a coordinate system converter.

Display image storage area 81 and imaging storage area 82
Is used by dividing a memory (not shown) into two areas. In this case, each area is at least 1 of the display image.
It has the capacity for an image. For example, in the case of VGA resolution, a capacity of 640 × 480 (pixels) × 3 (RGB) × 8 (color depth) = 7372800 (bits) is required.

As a basic operation of the difference extracting / calculating section 8, the image from the display element 2 which receives the image input is taken into the display image storage area 81. On the other hand, the image captured by the image sensor 6 from the screen 4 through the enlargement / reduction optical system 3 and further through the spectroscope 5 is captured from the image sensor 6 into the image storage area 82.

Next, the image in the display image storage area 81 and the image in the image pickup storage area 82 are fetched by the comparison calculator 83, and the difference extraction and the absolute coordinates of the point display are specified. That is, the comparison calculator 83 compares the display image with the captured image and extracts the absolute coordinates of the pixel having the difference. Next, coordinate system converter 8
Reference numeral 5 takes the difference between the coordinates stored in the separate coordinate storage area 84 and the absolute coordinates from the comparison calculator 83, and converts the absolute coordinates into relative coordinates.

FIG. 6 is an overall configuration diagram of the present invention. The relative coordinates obtained by the coordinate system converter 85 are sent to the coordinate output unit 86, and a signal conversion circuit (not shown) is used as an interface.
By using a PS / 2 mouse signal or a USB mouse signal, it can be used as a coordinate input device (mouse) of a personal computer (PC).

Further, without converting the coordinate system into relative coordinates by the coordinate system converter 85, the absolute coordinates in the comparison calculator 83 are also converted into interface signals by the coordinate output unit 87, and the RS232C cable or the USB cable is used. Then, by outputting to the coordinate input section of the personal computer, it can be used as an absolute coordinate input device such as a mouse or a tablet. That is, according to the present invention, when viewed from the personal computer side, it is a display device such as a display, and at the same time a coordinate input device such as a mouse or a tablet. There is an advantage not to.

[0022]

As described above, according to the present invention,
In a projector that prepares a screen separately and projects it on the screen, an optical coordinate input detection function was added to the projector itself, so there is no need for an expensive screen like the one covered with conventional sensors, and a laser that is normally used The pointer can be easily displayed with the pointer, which is very effective for presentations and the like.

[Brief description of drawings]

FIG. 1 is a principle diagram of an optical system of a general projector.

FIG. 2 is a principle diagram when a subject is photographed by a general camera or the like.

FIG. 3 is a block diagram of an image input device of a projector according to the present invention.

FIG. 4 is an explanatory diagram of position determination on a screen according to the present invention.

5 is a detailed block configuration diagram of a difference extraction / calculation unit shown in FIG.

FIG. 6 is an overall configuration diagram of the present invention.

[Explanation of symbols] 8 ... Difference extraction / calculation unit 81 ... Display image storage area 82 ... Imaging storage area 83 ... Comparison calculator 84 ... Coordinate storage area 85 ... Coordinate system converter

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Claims (4)

[Claims] 1. A coordinate input device used in a projector for projecting an image from a projection tube onto a screen provided separately, comprising: a display element for receiving light from a light source and outputting the image; and an image from the display element. A spectroscope that allows the light to pass therethrough, an enlargement / reduction optical system that optically enlarges the image from the spectroscope, a screen that displays an image of the enlargement / reduction optical system, and an image on the screen that is enlarged / reduced. An image pickup element that is reduced by an optical system and is captured through the spectroscope, a light ray pointer that displays a desired position on the screen by a pointer, and an image from the display element and an image pickup from the image pickup element are compared and different. And a difference extraction / calculation unit that specifies the absolute coordinates of the pointer display on the screen, converts the absolute coordinates into relative coordinates, and outputs the coordinates to the coordinate output unit to the personal computer. Coordinate input device of the projector. 2. The difference extraction / calculation unit, a display image storage area for storing an image from a display element receiving an image input,
An image capturing storage area for capturing an image captured from the screen through the enlargement / reduction optical system and further through the spectroscope, and an image in the display image storage area and an image in the image capturing storage area. A comparison operator for extracting and specifying the absolute coordinates of the pointer display on the screen, and the difference between the coordinates stored in a separate coordinate storage area and the absolute coordinates from the comparison operator is calculated to convert the absolute coordinates to relative coordinates. The coordinate input device for a projector according to claim 1, further comprising a coordinate system converter that performs conversion. 3. The projector coordinate input device according to claim 1, wherein the light beam type pointer is a laser pointer. 4. The coordinate input device for a projector according to claim 2, wherein the absolute coordinates are directly output from the comparison calculation unit to a coordinate output unit for a personal computer.