KR100623039B1 - System for measuring coordinates using light - Google Patents

Abstract

The coordinate measuring system according to the present invention is a coordinate measuring system which grasps the position coordinate of the light source C in order to input the position coordinate of the light source C to a computer; At least two reflectors reflecting light emitted from the light source; Condensing lenses respectively installed in front of the reflector; A CCD for converting light reflected from the reflector into an electrical signal and outputting the electrical signal; Optical delay means provided between the reflector and the CCD such that the light reflected from the reflector is input with a time difference to the CCD; And the position of the pixel to which light is input by receiving the electrical signal output from the CCD, and the incident point of the reflector therefrom to determine the angle between the line segment and the light source at both end points of the line segment connecting the incident points. And a micom that calculates the coordinates of the light source using the theorem of the trigonometric function. According to the present invention, unlike a digitizer using a digital pen or tablet which reads a paper printed with a special pattern by an optical method and reads coordinates, the position coordinates can be read without requiring a separate paper or pad. .

Digital pen, light source, coordinates, CCD, digitizer, trigonometric function

Description

System for measuring coordinates using light}             

1 is a view for explaining the principle of the coordinate measuring system according to the present invention;

2 is a view for explaining a coordinate measuring system according to a first embodiment of the present invention;

3 is a view for explaining a coordinate measuring system according to a second embodiment of the present invention.

<Description of Reference Numbers for Main Parts of Drawings>

C: light source 10: scanner

22, 24: CCD 30: microcomputer

40: interface 52, 54: condenser lens

62, 64: reflector 70: optical delay means

The present invention relates to a coordinate measuring system, and more particularly to a coordinate measuring system using light.

In computers, the keyboard and mouse are the most basic components and the main input devices. However, in recent years, due to the rapid proliferation of computers, the generalization of the Windows operating system and the spread of the Internet, these keyboards and mice are not enough to satisfy various needs in input methods. In particular, as digitizers have been used to meet such demands as various complicated functions that cannot be implemented with a conventional keyboard or mouse, such as high-level graphics, complicated drawing design, and handwriting input, have been used until now.

However, these digitizers are not only portable but large in size, and are very expensive, so they are limited to very specific fields. Therefore, in response to these demands, digital pens, which are relatively inexpensive than digitizers, have recently appeared.

In the case of the existing mouse, the movement direction or the distance of the pointer can be known, but the position of the pointer is not actually applicable to drawing or entering a long text because only the operation of the relative coordinate concept is unknown. However, in the case of the digitizer or the digital pen, it operates not only in the direction of movement and the distance but also in the concept of absolute coordinates that can know the position of the pointer, thereby satisfying all the above complicated functions.

Compared to tablet-type digitizers, the digital pen is an optical method, and uses a specially coded paper using very fine points or shapes. Digitel Pen is an internally mounted image sensor that reads a pattern corresponding to a certain area of the surface of the paper with an image sensor and reads the coordinates of the part from a special code that is coded as a point or a figure on the surface. Take Therefore, when using a digital pen, the function corresponding to the tablet of the digitizer (Tablet) can be replaced with a simple paper printed with a special pattern, which is inexpensive and easy to carry. However, in the case of the digital pen, it is also a problem to use a sheet printed with such a special code.

Therefore, the technical problem to be achieved by the present invention is to provide a coordinate measuring system that can measure the coordinates of the digital pen without using a separate sheet printed with a special code.

delete

Coordinate measuring system according to the present invention for achieving the above technical problem, as a coordinate measuring system for grasping the position coordinates of the light source to input the position coordinates of the light source to the computer; At least two reflectors spaced apart from each other by a predetermined distance to reflect light emitted from the light source; A condenser lens installed in front of the reflector such that the light reflected by the reflector is focused; A CCD that receives light reflected from the reflector from a pixel and converts the light into an electrical signal; Optical delay means provided between the reflector and the CCD such that the light reflected by the reflector is input to the CCD with a time difference; And grasping the position of the pixel to which the light is input by receiving the electrical signal output from the CCD, and identifying the incident point of the reflector therefrom to form the line segment and the light source at both end points of the line segment connecting the incident points to each other. And a microcomputer for calculating coordinates of the light source by using the trigonometric theorem after determining the angles, respectively.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail. The following embodiments are only presented to understand the content of the present invention, and those skilled in the art may make many modifications within the technical spirit of the present invention. Therefore, the scope of the present invention should not be interpreted as being limited to these embodiments.

[principle]

1 is a view for explaining the principle of the coordinate measuring system according to the present invention. Referring to FIG. 1, when there are two points A and B at a constant distance, the coordinates of the point C can be known by measuring the angle between the straight line connecting the point A and the point B and the point C.

Specifically, θ _c = 180 °-(θ _A + θ _B ) and the relationship of b = (sin θ _B / sin θ _C ) × C is established by the sine law of the trigonometric function, The coordinates are X = (sin θ _B / sin θ _C ) × sin (90 ° − θ _A ), Y = (sin θ _B / sin θ _C ) × sin θ _A.

Example 1

2 is a view for explaining a coordinate measuring system according to a first embodiment of the present invention. Here, point C is a light source provided to a digital pen.

In the scanner 10 for reading the position coordinate value of the light source C, two CCDs 22 and 24, two condenser lenses 52 and 54, a microcomputer 30, and an interface 40 are provided. In the present invention, the light source is not limited to a self-luminous body such as an LED, but also includes reflecting means mounted on a digital pen to reflect light from the outside to the CCD. When the reflecting means is provided in place of the self-luminous body, the scanner 10 may emit light so that the light reflected by the reflecting means reaches the CCD.

The two CCDs 22 and 24 are spaced apart from each other by a predetermined distance, and the condenser lenses 52 and 54 are provided in front of each of the CCDs 22 and 24. Therefore, the light emitted from the light source C is incident on the pixels of the CCDs 22 and 24 via the condensing lenses 52 and 54. According to the position of the light source C, the positions of the pixels of the CCDs 22 and 24 to which light is incident vary. At this time, since the position of the focus by the condenser lenses 52 and 54 also varies according to the distance between the light source C and the CCDs 22 and 24, the depth of focus by the condenser lenses 52 and 54 should be as deep as possible. If the intensity of the light emitted from the light source C can be sufficiently detected by the CCDs 22 and 24, a pin hole may be applied instead of the condensing lenses 52 and 54.

When the light is input to the pixels, the CCDs 22 and 24 convert the light into an electrical signal and output the electrical signal. The microcomputer 30 receives the electric signal output to the CCDs 22 and 24 to determine the position of the pixel. After determining the angle between the line segment and the light source C, that is, θ _A and θ _B , respectively, at both end points of the line segments connecting the pixels where the position is determined, the light source C is determined using the trigonometric function. Calculate the coordinates of The position coordinates of the calculated light source C are transmitted to the computer through the interface 40.

Since the scanner 10 calculates the coordinate value of the digital pen based on the light source C, the position where the actual pen tip contacts the coordinate value calculated by the scanner 10 may not match according to the angle of the pen. Can be. Therefore, the light source C is preferably positioned closest to the tip of the pen tip.

According to FIG. 2, a coordinate value of a digital pen moving on a plane may be measured. Therefore, if two CCDs are further installed on the line segments perpendicular to the line segments connecting the two CCDs 22 and 24 and subjected to the same calculation process as described above, three-dimensional coordinates in space can be measured. For example, if four CCDs are installed in a rectangular shape, the three-dimensional coordinate values of the digital pen can be read.

Although only the CCD is used as an example of the light detecting means, the present invention is not limited thereto, and any other means capable of detecting light may be replaced with the CCD.

Example 2

3 is a view for explaining a coordinate measuring system according to a second exemplary embodiment of the present invention, wherein the same reference numerals as those of FIG. 2 indicate components that perform the same function. To install a plurality of CCDs in the scanner 10 is expensive and bulky, so to compensate for this, only one CCD may be used as shown in FIG. 3.

The difference from FIG. 2 is that reflecting lenses 62, 64, rather than CCDs, are provided behind the condensing lenses 52, 54. FIG.

The light reflected by the reflectors 62 and 64 is collected by the condenser lenses 52 and 54 to be incident on the pixels of the CCD 22. Depending on the position of the light source C, the incident point incident on the reflecting mirrors 62 and 64 will be different, and accordingly, the position of the pixel on which light is incident will also vary.

Depending on the number of pixels of the CCD 22, the resolution of the coordinates of the light source C will vary. As shown in FIG. 3, if the two reflectors 62 and 64 share one CCD 22, the entire pixel may be changed. The two should be dedicated to reflector 62 on one side and 64 on the other. In this case, the number of pixels involved in one reflector is reduced and the resolution is lowered. Of course, increasing the number of pixels will improve the resolution, but increasing the number of pixels in the CCD causes an increase in the volume and manufacturing cost of the CCD.

Thus, the light reflected from the two reflectors 62, 64 arrives at the CCD 22 with time difference in order to allow the two reflectors 62, 64 to share the entire pixel in one CCD 22. It is preferable to provide the optical delay means 70 between the CCD 22 and the reflecting mirrors 62 and 64. The optical delay means may be provided on either side or on both sides.

The microcomputer 30 receives the electrical signal output from the CCD 22 to grasp the coordinates of the pixel into which the light is input, and to determine the incidence points of the reflectors 62 and 64 therefrom to connect the incidence points to each other. After determining the angle between the line segment and the light source C at each end point, the coordinates of the light source C are calculated using the trigonometric theorem.

As described above, according to the present invention, unlike a digitizer using a digital pen or tablet which reads paper printed with a special pattern in an optical method and reads coordinates, the position coordinates are read without requiring a separate paper or pad. You can do it.                     

Therefore, it does not require a separate consumables (special printing paper) is easy to use and economical, and does not require a separate tablet, so it is easy to carry or move. In addition, in the coordinate recognition method, three-dimensional coordinate recognition in space as well as in the plane is possible, so that the future technology and application range is very wide.

Claims (5)

delete A coordinate measuring system for grasping a position coordinate of a light source for inputting a position coordinate of a light source into a computer, At least two reflectors spaced apart from each other by a predetermined distance to reflect light emitted from the light source; A condenser lens installed in front of the reflector such that the light reflected by the reflector is focused; A CCD that receives light reflected from the reflector from a pixel and converts the light into an electrical signal; Optical delay means provided between the reflector and the CCD such that the light reflected by the reflector is input to the CCD with a time difference; And The angle formed by the line segment and the light source at both end points of the line segment connecting the incidence points to each other by grasping the position of the pixel to which the light is input by receiving the electrical signal output from the CCD. And a microcomputer that calculates coordinates of the light source by using the theorem of the trigonometric function after determining each of the coordinates. The coordinate measuring system according to claim 2, wherein the light source is installed in a digital pen. The coordinate measuring system according to claim 2, wherein the light source is made of a self-illuminating body installed in a digital pen. The coordinate measuring system according to claim 2, wherein the light source is installed in a digital pen and comprises reflecting means for reflecting external light to the condensing lens.

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