JPH0542509Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a cursor used for specifying input coordinates in a two-dimensional coordinate input device, and particularly relates to an optically reflective input coordinate specifying cursor.

[Conventional technology]

Conventionally, various types of coordinate input devices for specifying and inputting two-dimensional coordinates have been known, such as magnetostrictive type, electromagnetic induction type, pressure sensitive type, and electrostatic induction type. All conventional coordinate input devices basically have a coordinate specifying section consisting of a combination of a tablet defining a two-dimensional coordinate plane and a cursor movable on the tablet. The cursor and the tablet are connected by electrical, magnetic, or mechanical signals, and through the exchange of these signals, the position of the cursor on the two-dimensional coordinate plane is detected, and input coordinates are designated.

[Problem that the invention attempts to solve]

However, in the conventional method described above,
The cursor is always used in combination with a dedicated tablet that can send and receive signals, and cannot be applied to any two-dimensional coordinate plane apart from the tablet. Furthermore, the planar dimensions of the dedicated tablet are physically limited, and the cursor cannot freely input a wide range of two-dimensional information.

In view of the above-mentioned problems with conventional cursors, the present invention provides a cursor that can be applied to any two-dimensional coordinate plane without being constrained by the tablet in principle, and that has virtually no restrictions on the designated coordinate input range. aim at something.

[Means for solving problems]

According to the present invention, the cursor has an optical reflective structure. The position of such a light-reflecting cursor on a two-dimensional coordinate plane is detected based on the principle of triangulation using a laser beam. In other words, a light-reflecting cursor receives two laser beams emitted from a pair of light sources arranged on an arbitrary two-dimensional coordinate plane and separated from each other by a predetermined distance, and reflects these laser beams to create a flat surface. The light is then returned to a pair of light sources through the same optical path. The position of the cursor is determined by the principle of triangulation based on the length of the reference line connecting the pair of light sources and the angle that each of the two laser beams makes with the reference line.

In order to enable triangulation using such a laser beam, a light reflective cursor must have the following two optical functions. In other words, it has a function that selectively reflects incident light rays directed toward the central axis representing the cursor position and returns the reflected light rays to the light source of the incident rays, and a function that allows continuous coordinate input by manually moving the cursor on a plane. This function is to keep the reflected light beam constant so that it does not substantially deviate from the optical path of the incident light beam even if the cursor is tilted with respect to the coordinate plane during movement. If the reflected light ray deviates from the predetermined optical path, detection becomes impossible and therefore coordinate input cannot be specified.

In order to ensure the above function, the light reflective cursor according to the present invention has an annular lens member. This annular lens member is composed of an optical material formed into an annular shape having a concentric inner circumferential surface and an outer circumferential surface, and the inner circumferential surface section is parallel to the concentric axis in a cross section cut along an arbitrary plane including the concentric axis. By forming a cylindrical inner circumferential surface so that the outer circumferential surface cross section curves outward with a predetermined curvature, a lens surface having an optical axis along the ring radial direction is formed. is provided, and the focal point of the lens is located on the inner circumferential surface. A reflective layer is provided along the inner circumferential surface of the annular lens member, and reflects an incident light beam incident along a plane including a concentric axis and a radial optical axis, and emits a reflected light beam parallel to the incident light beam. In addition, the light reflection type cursor according to the present invention includes a support member for supporting the annular lens member and moving the annular lens member on the coordinate plane while keeping the concentric axis perpendicular to the given coordinate plane, and the annular lens member. It has an aiming member for aligning the center point through which the concentric axes of the members pass with a specific point to be specified on the coordinate plane.

[Effect]

According to the present invention, incident light rays directed along the radial optical axis of the annular lens member toward its concentric axis pass through the outer circumferential surface and then perpendicularly enter the inner circumferential surface. This incident light beam is vertically reflected by the light reflection layer provided along the inner peripheral surface, and follows the same optical path as the incident light beam in reverse, as if it were emitted from a concentric axis, and is directed toward a distant light source where it is received. be done. Therefore, the incident rays directed toward the concentric axis are selectively reflected, and the optical path of the reflected rays coincides with that of the incident rays, thus ensuring the first function required of the cursor described above.

Also, even if the concentric axis of the cursor is slightly tilted during coordinate input operation, the incident light rays incident along the plane including the concentric axis and the radial optical axis will be directed onto the inner peripheral surface by the outer peripheral lens surface of the annular lens member. always converges to The converged incident light beam is reflected by a reflective layer along the inner circumferential surface, and is emitted while remaining parallel to the incident light beam, due to the so-called cat's eye effect, toward a distant light source. The incident ray and the reflected ray always maintain a parallel relationship even if the concentric axis is tilted with respect to the plane, so they will never separate from each other, and the reflected ray will always be effective due to the light receiving part adjacent to the distant light source. The second required function described above can be secured.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a light reflective cursor according to the present invention and an example of a two-dimensional coordinate input method using a light reflective cursor will be described in detail below with reference to the drawings.

FIG. 1A is a plan view of a light reflective cursor according to the present invention. The annular lens member 1 is made of an optical material, such as high refractive glass SLF-03 having a refractive index of 1.83, which is formed into an annular shape having a concentric inner circumferential surface 2 and an outer circumferential surface 3. A light reflective layer 4 along the inner circumferential surface 2
is formed. The light reflecting layer 4 is made of a metal vapor deposited film such as aluminum or metal foil.
This annular lens member 1 is supported by a support member 5 at its non-effective outer periphery, and
It is designed to be able to move on the coordinate plane while keeping the concentric axis perpendicular to the XY coordinate plane. In the center of the annular lens member 1, there is a center point P ₀ through which the concentric axis passes.
A aiming member 6 is arranged to align with a specific point to be designated and input on the XY coordinate plane. The member 6 has a hair cross line like a sight.

FIG. 1B is a cross-sectional view of the cursor shown in FIG. 1A taken along a plane including the concentric axis 7 of the annular lens member 1 and a line connecting the center point P ₀ and one light source P ₁ . A cross section of the inner peripheral surface 2 of the annular lens member 1 is parallel to the concentric axis 7. The cross-section of the outer circumferential surface 3 is polished and curved outward at a predetermined curvature, and the outer circumferential surface 3 constitutes a lens surface having an optical axis 8 along the radial direction of the ring.
The curvature is set so that the lens focal point is located on the inner circumferential surface 2. At this time, in order to reduce the wall thickness between the outer circumferential surface 3 and the inner circumferential surface 2 and to downsize the cursor, the optical material of the annular lens member 1 is preferably one with a high refractive index. An incident light beam 9 incident from a distant light source P ₁ is reflected by the reflective layer 4 and output as a reflected light beam 10 .

The aiming member 6 arranged at the center of the annular lens member 1 is composed of, for example, a fiber optic plate. In other words, the aiming member 6 is located on the XY coordinate plane 1
1 and a top surface 1 parallel to the bottom surface 12.
3, a parallel bundle of optical fibers 14 connecting the bottom and top parts, and a hair cross line mark aligned with the center point _P0 . Further, the support member 5 has a bottom surface portion 15 in sliding contact with the coordinate plane 11, and a lens member 1 on the bottom surface portion 15.
The annular lens member 1 has a fixing portion 16 for fixing and holding the non-effective outer circumferential surface portion of the annular lens member 1 so that the concentric axis 7 of the annular lens member 1 is vertical.

Next, the first method of using the cursor according to the present invention will be described.
This will be explained according to Figures A and B. First, hold the cursor support member 5 on a predetermined XY plane,
The aiming member 6 is used to align the center point of the cursor, that is, the center point P ₀ of the annular lens member 1, with the specific point to be designated as a desired input. At this time, since the aiming member 6 is composed of a fiber optic plate as described above, the aiming member 6 is in contact with the bottom part 12.
The image on the XY coordinate plane is transmitted through the intermediate optical fiber bundle 14, stored as it is, and focused on the corresponding upper surface portion 13. Since this image formation has virtually no parallax, while looking at this image formation, the intersection of the hair cross lines provided on the aiming member 6, that is, the center point.
You can aim at P ₀ and specify the desired point accurately.

Next, with the center point P ₀ of the cursor aligned with the coordinate point to be input, set the predetermined distance L.
A pair of light sources P ₁ and P ₂ separated by a distance emit incident light rays that are each angularly scanned along a coordinate plane. As shown in FIG. 1B, when the incident light ray 9 emitted from the other light source P ₁ coincides with the optical axis 8 connecting the center point P ₀ of the apex cursor and the light source P ₁ , the incident light ray 9 forms an annular shape. It is vertically reflected by the reflective film 4 of the lens member 1, and the reflected light beam 10 travels backward along the same optical path as the incident light beam 9 in plan view, returns to the light source _P1 , and is received and detected there. At this time, the angle φ ₁ between the optical path of the incident and reflected light rays 9 and 10 and the reference line connecting the pair of light sources P ₁ and P ₂ is determined. Similarly, for the other light source P ₂ , the angle φ ₂ between the optical path when the incident and reflected rays coincide when seen in a plan view and the reference line is determined. Based on these obtained angle values φ ₁ and φ ₂ and the distance L between the pair of light sources,
The coordinates of the center point P ₀ of the cursor are determined by the principle of triangulation, and the desired coordinate point is entered.

By the way, as shown in FIG. 1C, in the continuous coordinate designation mode, during continuous movement of the cursor, the bottom surface of the annular lens member 1 separates from the XY coordinate plane 11, and the concentric axis 7 temporarily moves away from the coordinate plane 11. A situation where the vehicle tilts may also occur. For example, this may be caused by blurring of the hand of the operator who grips the support member 5 of the cursor.
Even in such a tilted state, the reflected light beam 10 can substantially match the optical path of the incident light beam 9 in plan view and travel backward. That is, the incident light ray 9 traveling in a plane including the concentric axis 7 and the radial optical axis is refracted and converged by the lens surface formed by the outer circumferential surface 3 of the annular lens member 1, and is provided along the inner circumferential surface 2. An image is formed on the reflective layer 4. The focal point of the lens surface is the inner peripheral surface 2
This is because the curvature of the lens surface is set so that it exists on the top. Therefore, the reflected light ray 10 reflected by the reflective layer 4 is refracted by the outer peripheral surface 3 of the lens due to the so-called cat's eye effect, and then is emitted parallel to the incident light ray 9 and travels backward to return to the distant light source. Since the incident light ray 9 and the reflected light ray 10 are parallel to each other, they do not separate from each other.

Assuming that the cursor is simply made up of a cylindrical reflector, if the axis of the cylinder is tilted with respect to the coordinate plane, the incident ray will naturally not be perpendicular to the reflector, The reflected light beam then travels in a direction different from the optical path of the incident light beam, and never returns to the distant light source. Therefore, if the cylindrical axis is tilted, triangulation using optical path matching of incident rays becomes impossible, whereas with the cursor according to the present invention, even if the concentric axis is tilted, no substantial damage will occur. Triangulation can continue without being affected.

Finally, the configuration and operation of the two-dimensional coordinate input device using a light reflective cursor according to the present invention will be explained with reference to FIGS. 2A and 2B, 3, and 4.

FIG. 2A is an external perspective view of the two-dimensional coordinate input device, and FIG. 2B is a layout diagram of its optical system. In the figure, 17 is an optical system circuit housing part, 20 is an input board, and 3
0 is a two-dimensional XY coordinate input area, 110 is a light reflective cursor or position indicator of the present invention, 121, 12
2 is a laser light source, 123 and 124 are half mirrors, 125 and 126 are first and second rotating mirrors, and 127 and 128 are first and second optical sensors.

The laser light sources 121 and 122 are each composed of a semiconductor laser, and the laser light emitted from the laser light source 121 is arranged on the origin P ₁ of the XY plane via a half mirror 123 arranged on the X-axis. The rotation axis of the first rotating mirror 125
It is designed to be incident parallel to the XY plane.
The laser light emitted from the laser light source 122 is transmitted to the first rotating mirror 125 at a predetermined distance L, for example, 5 m, via a half mirror 124 arranged on the X-axis.
The beam is made incident parallel to the XY plane onto the rotation axis of the second rotating mirror 126, which is disposed on the X-axis _P2 with the beam spaced apart from the beam. Further, the first and second optical sensors 127 and 128 are each made of an NPN type phototransistor, and each collector is connected to a DC power supply. First optical sensor 127
is arranged at a position where the laser beam emitted from the laser light source 121 is reflected by the first rotating mirror 125 in the same direction as the incident light on the first rotating mirror 125 and can be detected via the half mirror 123. It is set up. The second optical sensor 128 is configured such that the laser beam emitted from the laser light source 122 is transmitted to the second rotating mirror 126 by the second rotating mirror 126.
The half mirror 124 is arranged at a position where the laser beam reflected in the same direction as the incident light can be detected via the half mirror 124.

FIG. 3 is an electrical circuit block diagram of the two-dimensional coordinate input device. In the figure, 131 is a first rotating mirror drive unit that rotates the first rotating mirror 125 shown in FIG. 2B in a counterclockwise direction at a constant angular velocity ω. Furthermore, when the normal line of the mirror surface of the first rotating mirror 125 coincides with the incident light path from the laser light source 121, the predetermined pulse width Tp _w becomes logic "1".
A pulse signal A is output. The pulse width _Tpw of the pulse signal A is smaller than the time Tf required for the first rotating mirror 125 to rotate once.
132 is a second rotating mirror drive unit that rotates the second rotating mirror 126 shown in FIG. 2B in a clockwise direction at a constant angular velocity ω. Furthermore, when the normal line of the mirror surface of the second rotating mirror 126 coincides with the incident light path from the laser light source 122, a predetermined pulse width is reached.
A pulse signal B of logic "1" of Tp _w is output. The pulse width _Tpw of the pulse signal B is smaller than the time Tf required for the second rotating mirror 126 to rotate once.

Reference numerals 141 and 142 indicate level detection circuits, each of which is configured identically by a resistor and an operational amplifier.
The level detection circuit 141 is connected to the first optical sensor 127
The photocurrent output from the emitter is converted into a voltage, and when this voltage exceeds a predetermined detection reference level, the output signal is set to logic "1". The level detection circuit 142 converts the photocurrent output from the emitter of the second photosensor 128 into a voltage, and sets the output signal to logic "1" when this voltage exceeds a predetermined detection reference level.

143 is a clock signal generation circuit, which generates a clock signal at a predetermined period.
Outputs the Tck clock signal CK.

Pulse shaping circuits 144 to 147 each consist of a flip-flop and a logic circuit, and output a pulse signal of one clock pulse width upon detecting that the input signal changes from logic "0" to logic "1". The pulse shaping circuit 144 receives the output signal A of the first rotating mirror drive section 131 and the clock signal.
Inputs CK and outputs signal C. The pulse shaping circuit 145 receives the output signal of the level detection circuit 141 and the clock signal CK, and outputs a signal E.
The pulse shaping circuit 146 receives the output signal B of the second rotating mirror drive section 132 and the clock signal CK, and outputs the signal D. Pulse shaping circuit 147
inputs the output signal of the level detection circuit 142 and the clock signal CK, and outputs the signal F.

Counters 148 and 149 perform free counting in response to the clock signal CK. Also,
Counter 148 is reset by pulse signal C output from pulse shaping circuit 144, and counter 149 is reset by pulse signal D output from pulse shaping circuit 146.

150 is an interrupt signal generation circuit, which is composed of a flip-flop and a logic circuit, and is connected to the pulse shaping circuit 1.
45, 147 output signals E, F and clock signal
CK is input, and the interrupt signal INT is set to logic “1” when one pulse signal of signals E and F is input and then the other pulse signal is input, or when two pulse signals are input at the same time. Then, the CPU 155, which will be described later, outputs the data. Also, CPU15
When a pulse-like reset signal R of logic "1" is input from 5, the interrupt signal INT is set to logic "0".

151 and 152 are registers, register 151
The input of the counter 148 is connected to the output of the counter 148, and the output data of the counter 148 is latched at the front end of the pulse signal E output from the pulse shaping circuit 145. The input of the register 152 is connected to the output of the counter 149, and latches the output data of the counter 149 at the front end of the pulse signal F output from the pulse shaping circuit 147. 153 and 154 are tri-state output type registers, the input of register 153 is connected to the output of register 151, and when the interrupt signal INT changes from logic "0" to logic "1", the output data of register 151 is output. Latch. The input of register 154 is connected to the output of register 152 and latches the output data of register 152 when interrupt signal INT changes from logic "0" to logic "1".

A CPU 155 is connected to the outputs of the registers 153 and 154 via a data bus DB, and inputs data held in the registers 153 and 154 when the interrupt signal INT becomes logic "1". Also, after inputting the data, output port P1
A pulse-like reset signal R of logic "1" is output to the output terminal.

The laser beam angle detection means includes first and second rotating mirror drive units 131 and 132, a clock signal generation circuit 143, and a pulse shaping circuit 144 and 14.
6. Consists of counters 148 and 149.
Further, the coordinate value calculation means is the level detection circuit 14.
1, 142, clock signal generation circuit 143, pulse shaping circuit 145, 147, interrupt signal generation circuit 150, registers 151 to 154, CPU 15
5 and a program to be described later that operates the CPU.

Next, the operation of the two-dimensional coordinate input device having the above-mentioned configuration will be explained based on the program flowchart shown in FIG.

As shown in FIG. 2B by the position indicator 110
A case will be described in which the position of a point P whose coordinates are to be input on the XY plane is input. position indicator 110
Move on the XY plane and find the intersection of hair cross lines P ₀
Align with point P.

When the laser light emitted from the laser light source 121 enters the first rotating mirror 125 at an incident angle θ1 via the half mirror 123, the reflected light is directed toward the concentric axis of the position indicator or cursor 110. Then, the laser beam reflected by the reflective layer of the cursor enters the first optical sensor 127 via the first rotating mirror 125 and the half mirror 123. At this time, the photocurrent output from the first optical sensor 127 increases, the output signal of the level detection circuit 141 becomes logic "1", and the pulse shaping circuit 14
5 outputs a pulse signal E. Further, if the laser light emitted from the laser light source 122 is incident on the second rotating mirror 126 through the half mirror 124 at an incident angle θ2, and the reflected light is directed toward the concentric axis of the cursor 110, the reflection of the cursor The laser beam reflected by the layer passes through the second rotating mirror 126 and the half mirror 124 to the second optical sensor 128.
incident on . At this time, the photocurrent output from the second photosensor 128 increases, and the level detection circuit 1
The output signal of 42 becomes logic "1", and the pulse signal F is output from the pulse shaping circuit 147.

In response to the pulse signal E, the output data of the counter 148 is latched in the register 151 and held as angle data D1 representing the incident angle θ1 of the laser beam on the first rotating mirror 125. Further, the output data of the counter 149 is latched in the register 152 by the pulse signal F, and is held as angle data D2 representing the incident angle θ2 of the laser beam on the second rotating mirror 126. Further, angle data D1 and D2 are latched in registers 153 and 154 by an interrupt signal INT.

The CPU 155 constantly monitors whether or not the interrupt signal INT is logic "1" (S1), and when the interrupt signal INT becomes logic "1", the CPU 155 outputs the angle data from the register 153 via the data bus DB. D1 is input (S2), and angle data D2 is input from the register 154 (S3). Next, output port P
1 for a predetermined period of time (S4),
It is determined whether the angle data D1 is 0 (S5). As a result of this determination, when the angle data D1 is 0, the process moves to S1, and when it is not 0, it is determined whether or not the angle data D2 is 0 (S6). As a result of this determination, when the angle data D2 is 0, the process moves to S1, and when it is not 0, the first rotating mirror 1 is
The incident angle θ1 of the laser beam to the second rotating mirror 125 and the incident angle θ2 of the laser beam to the second rotating mirror 126 are calculated by the following equation (S7).

θ1=2π・Tck・D1/Tf (radian) …(1) θ1=2π・Tck・D2/Tf (radian) …(2) Here, Tck is the period of the clock signal CK, and Tf is the first and second This is the time required for the rotating mirrors 125 and 126 to rotate once, and is set in advance as a constant in the program.

Furthermore, by doubling the incident angles θ1 and θ2, the first and second rotating mirrors 125 and 126
The angles φ1 and φ2 are found between the incident light and the reflected light at each point (S8).

φ1=2・θ1 …(3) φ2=2・θ2 …(4) Next, point P is determined by the principle of triangulation based on the following formula.
The X and Y coordinate values of are calculated (S9).

x=L・tanφ2/(tanφ1+tanφ2)...(5) y=L・tanφ1・tanφ2/(tanφ1+tanφ2)...(6) Here, L is the distance between the first rotating mirror 125 and the second rotating mirror 126. The distance is preset in the program as a constant.

After calculating the X coordinate value and Y coordinate value, the process moves to S1.

In this embodiment, as shown in FIG. 2A, the cursor is placed on an input board having a finite area. However, in principle, the cursor can be used without any restrictions as long as it is within the reach of the laser beam, and can be applied to any horizontal or vertical plane.
Further, in this embodiment, as shown in FIG. 2B, the optical system is composed of a rotating mirror, a half mirror, etc. However, this is only one example, and various other modifications are possible and are disclosed in Japanese Patent Application No. 63-270519.

[Effect of idea]

As explained above, the light-reflecting cursor according to the present invention uses an annular lens member, forms a light-reflecting film on the inner circumferential surface, and uses the outer circumferential surface as a lens surface with a predetermined curvature, and the lens focal point is set on the inner circumferential surface. Since the structure is set on a plane, the light rays incident on the concentric axis of the lens member are reflected by the reflective film, and then go backwards along the same optical path as the incident light rays when viewed from the plane and reach the light source. Since it returns, it can be used as an input indicator of a two-dimensional coordinate input device based on the triangulation method using laser light.

The cursor according to the present invention can be applied to any input coordinate board, and input coordinates can be specified over a wide range within the range covered by the laser beam.

Furthermore, even if, for example, the concentric axis of the cursor is tilted during movement of the cursor, the reflected ray is always retraced parallel to the incident ray, so that there is no risk of interrupting the continuous triangulation.

Further, since the reflective layer is provided along the inner circumferential surface of the annular lens member, there is less risk of damage or staining due to carelessness of an operator or the like.

In addition, since the outer circumferential surface of the annular lens member is not a reflective surface but merely a lens surface, even if it becomes dirty due to adhesion of foreign matter during use, it can be easily wiped off.

[Brief explanation of drawings]

Figure 1A is a plan view of the light reflective cursor, Figure 1B is a cross-sectional view, Figure 1C is an explanatory diagram of the functions of the light reflective cursor, and Figure 2A is coordinate input using the light reflective cursor. A perspective view of the external appearance of the device, FIG. 2B is a layout diagram of the optical system, FIG. 3 is a block diagram of the electrical circuit, and FIG. 4 is a program for controlling the operation of the electrical circuit shown in FIG. 3. It's a chat. 1... Annular lens member, 2... Inner peripheral surface, 3...
Outer peripheral surface, 4... reflective layer, 5... support member, 6...
Aiming member, 7... Concentric axis, 8... Optical axis.

Claims (1)

[Claims for Utility Model Registration] 1. Comprised of an optical material formed into an annular shape having a concentric inner circumferential surface and an outer circumferential surface, in a cross section cut along a plane including the concentric axis, the inner circumferential surface cross section is aligned with the concentric axis. By forming the inner circumferential surface so that they are parallel to each other and forming the outer circumferential surface so that the cross section of the outer circumferential surface curves outward at a predetermined curvature, a lens surface having an optical axis along the ring radial direction is created. an annular lens member provided along the inner peripheral surface of the annular lens member, the lens focal point of which is located on the inner peripheral surface; a reflective layer for emitting a reflected ray parallel to the incident ray; and a support member for supporting the annular lens member and moving it on the coordinate plane while keeping the concentric axis perpendicular to the given coordinate plane. and an aiming member for aligning a center point through which the concentric axis of the annular lens member passes with a specific point on a coordinate plane. 2. The cursor according to claim 1, wherein the annular lens member is made of high refractive index glass and has a polished outer peripheral surface. 3. Claim 1, wherein the reflective layer is composed of a metal thin film.
cursor as described in . 4. The support member according to claim 1, wherein the supporting member has a bottom surface that is in sliding contact with the coordinate plane and a fixing section for fixing the annular lens member so that the concentric axis is perpendicular to the bottom surface. cursor. 5. The aiming member is mounted inside the annular lens member, and has a bottom part in contact with the coordinate plane, a top part parallel to this, a parallel bundle of optical fibers connecting the bottom part and the top part, and a hair cross mark. 2. The cursor of claim 1, comprising a fiber optic plate.