JPH0119178B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical scanning input device, and more particularly to an optical scanning input device that inputs coordinates by detecting a beam of light scanning a coordinate plane with a light pen.

In recent years, one type of coordinate input device is to scan a coordinate plane with light, detect this scanning beam with a light pen, or use a sensor to detect when the scanning beam is blocked by an obstacle to input coordinates.
Research and development of so-called optical scanning input devices is being actively conducted. This optical scanning input device is characterized by being resistant to electrical noise and capable of reliable coordinate input without requiring any special configuration on the tablet surface itself, which serves as a coordinate plane.

FIG. 1 shows an example of a conventional optical scanning input device. In the figure, Fresnel mirrors X1 and X2, Y1 and Y2 are provided facing each other on four sides of the input plane, and a rotating mirror (scanner) 1 and a sensor 2 are arranged diagonally. The rotating mirror 1 is a mirror 3.
It has a function of deflecting and scanning the beam light (laser light, etc.) sent from the light source 4 via the sensor 2 to the Fresnel mirrors X1 and Y1 placed on two adjacent sides. On the other hand, the Fresnel mirrors X1 and Y1 are
The angles of the Fresnel mirrors X2 and Y2 are adjusted so that the incident light sent from the rotating mirror 1 is reflected parallel to the y and x axes, and the angles of the Fresnel mirrors X2 and Y2 are adjusted so that the parallel rays are focused onto the sensor 2. has been done. By rotating the rotating mirror 1 at a constant speed, the beam light scans the coordinate plane, and this light beam is reflected by the Fresnel mirrors X1, X2 or Y1, Y2, and is all focused on the sensor 2. It is deployed in If an obstacle is placed at point P, the light beams BE, AB, and OA will pass through point P one after another, and the waveform of light received by the sensor will become as shown in Figure 2.
Therefore, from this waveform, P of each ray BE, AB, OA
If the point passing timings t ₁ to _{t 3} are determined and calculated, the position coordinates (x) can be detected.

However, in such conventional technology, calculation processing must be performed based on a plurality of detection timings to obtain position coordinates, which has the disadvantage of complicating the circuit configuration and requiring time to input the coordinates. .

The present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to provide an optical scanning input device that can quickly input coordinates with a simple configuration by using a single scanning beam on an input plane. , its purpose.

The present invention includes a light source that emits a beam of light, a rotating mirror that deflects and scans the beam of light emitted from the light source to two adjacent sides on the back side of the tablet, and a rotating mirror that deflects and scans the beam of light emitted from the light source to two adjacent sides of the tablet. The device is equipped with an X and Y reflecting mirror that reflects the incident light sent from the rotating mirror toward the surface of the tablet and scans in the x and y directions, and the light pen detects the scanning light from the X and Y reflecting mirror. The purpose is to achieve the above objective by inputting coordinates.

Hereinafter, one embodiment of the present invention will be described based on FIGS. 3 to 6.

FIG. 3 is a schematic diagram showing the input section of the optical scanning input device according to the present invention. In the figure, reference numeral 10 denotes a tablet surface that is formed into a rectangular plate shape and serves as an input plane.
reflective mirrors 1 in the x direction, each at an outer position close to
1 and y-direction reflecting mirrors 12 are arranged. Further, a rotating mirror 13 is provided on the outside of the lower left corner of the tablet board 10 in FIG. 3. A beam of light is incident on this rotating mirror 13 from a light source (a laser or an iodine lamp equipped with a condensing lens and a slit) 14 provided at the lower right of the tablet surface 10, and the rotating mirror 13 The mirror 13 is a mirror drive unit 13
By being rotated clockwise at a constant speed by A, the light beam incident from the light source 14 is directed radially toward the upper and right sides of the tablet surface 10, and the back side of the tablet surface 10 is rotated toward the surface of the tablet surface 10. The deflection is scanned parallel to the back surface from the top side to the right side. The light sent from the rotating mirror 13 is transmitted to the reflecting mirrors 11 and 1.
2 and is reflected by the reflecting mirrors 11 and 12 toward the surface of the tablet surface 10 in parallel with the y and x axes, respectively. To be more specific, the reflecting mirrors 11 and 12 include a large number of reflecting blocks 21, 21, . . . , 22, which are formed in substantially the same shape.
22, . . . are each linearly integrated with the rotating mirror 13 at a predetermined inclination angle. As shown in FIG. 5, the reflection block 21 has a height greater than the thickness of the tablet surface 10, is disposed spanning from the back surface to the front surface of the tablet surface 10, and is located at the top of the tablet surface 10. A corner reflecting section 23 consisting of two orthogonal reflecting planes 21A and 21B is formed on the side facing the left end surface 10A in FIG. 5 (see FIG. 4). This corner reflecting section 23 has the function of reflecting the beam light incident parallel to the back surface of the tablet surface 10 in parallel to the surface side of the tablet surface 10. By arranging this reflection block 21 at a predetermined angle in a horizontal plane (within the plane of the paper in FIG. 3), the light beam incident from the rotating mirror 13 is reflected in a direction parallel to the y-axis. (See arrow A in Figure 3). The other reflecting blocks 21, 21, . . . are formed in the same manner, and therefore, based on the action of the reflecting mirror 11, the surface side of the tablet surface 10 is sequentially scanned in the x direction with light rays parallel to the y axis. The reflecting mirror 12 is constructed in exactly the same way as the reflecting mirror 11, and is configured to sequentially scan the front side of the tablet board 10 in the y direction with light rays parallel to the x axis (see arrow B in FIG. 3). reference). Therefore, during one rotation (one scan) of the rotating mirror 13, the tablet surface 10 is scanned once in each of the x direction and the y direction. Here, by appropriately setting the block lengths 1 ₁ and 1 ₂ of the reflection blocks 21 and 22 and the narrowing down of the beam light, a predetermined resolution can be obtained.

In the input section configured in this way, the point Q(x,
The coordinates of y) are as follows: _x =L/tanθ _{x −X L y=M, where the deflection angle (with respect to the x-axis) of the rotating mirror 13 at the timing when the scanning light passes point Q is θ x} and _{θ y} /tanθ _y −Y _M (where L and M are reflection mirrors 1
1, 12 and the rotating mirror 13, X _L ,
_YM is the distance in the y and x directions between the origin O of the tablet surface 10 and the rotating mirror 13).

FIG. 6 is an electrical configuration diagram for performing coordinate detection according to this embodiment. In the figure, reference numeral 30 denotes a light pen, and by touching the light pen 30 to a desired coordinate position Q (see Fig. 3) on the tablet surface 10 and detecting the scanning light, the light pen 30 can be detected at the corresponding contact position. It is designed to allow coordinate input. The light pen 30 includes a cylindrical casing 31, a light guide 32 provided at the tip of the casing 31, and a sensor 33 provided opposite to the rear end of the light guide 32. When light is incident on the light guide 32, the light guide 32 undergoes diffuse reflection, scattering, etc.
For example, the light guide 32 is made of a transparent member mixed with a large number of air bubbles, and has a tip protruding from the casing 31, and when the scanning light hits the light guide 32, ,
The scanning light is guided toward the rear end by the scattering effect of air, and the scanning light is detected by the sensor 33. This scanning light detection operation is performed after the light pen 30 comes into contact with the tablet surface 10.
It is arranged that scanning of the tablet surface 10 starting from the beginning of the direction is carried out only during two scans. The detection signal of the sensor 33 is amplified to a predetermined level by an amplifier (not shown), then waveform-shaped by a waveform shaping circuit 38 and output to a gate circuit 39. The tablet surface 10
At the starting ends of the upper and right sides in FIG.
6,37 is equipped. These sensors 3
6 and 37 are conductive and “ON” while light is incident.
, output high signals to the S and R terminals of the R-S flip-flop (hereinafter simply referred to as "R-S [F/F]") 40, and output the high signals to the Q terminal of the R-S [F/F] 40. An x-direction scanning start signal and a y-direction scanning start signal, which is distinguished between high and low, are sent to the gate circuit 39. This gate circuit 39 converts the detection signal output from the waveform shaping circuit 38 into R-S
While a high signal is being input from the [F/F] 40, it is sent to the distribution circuit 51 of the X position information generating section 50, while while a low signal is being input from the R-S [F/F] 40. It has a function of sending the Y position information to a distribution circuit (not shown) of the Y position information generating section 60.

The X and Y position information generating sections 50 and 60 are configured in exactly the same way. Of these, the X position information generating section 50 will be explained as follows.
x obtained in the first scan of the tablet surface 10
The first detection signal related to the direction is outputted to the latch circuit 52 as a latch strobe signal, and the second detection signal obtained in the second scan is outputted to the comparison circuit 53 as a comparison strobe signal. The latch circuit 52 includes the mirror drive section 13A.
Deflection angle data (the angle between the positive direction of the x-axis and the deflected light beam) is constantly input from a deflection angle detector 70 attached to the deflection angle detector 70 . This latch circuit 5
2 latches the deflection angle data at that timing when the latch strobe signal is input from the distribution circuit 51 and outputs it to the output gate 54.
Further, the comparison circuit 53 compares the output data of the deflection angle detector 70 and the data latched by the latch circuit 52 at the timing when the comparison strobe signal is inputted from the distribution circuit 51. The output gate 54 is opened and the data of the latch circuit 52 is outputted to the arithmetic processing section 80 as correct deflection angle data θ _x in the x direction. In this comparison operation, the accuracy of the coordinate data touched by the light pen 30 is confirmed by scanning the tablet surface 10 twice, and the influence of noise etc. is removed to improve the reliability of data input. It is done for the purpose of

The arithmetic processing section 80 includes the X position information generation section 50
Based on the deflection angle data θ _x sent from the controller, the following calculation is performed: x=L/tan _θ x _−XL and output as x coordinate data to an information processing device or the like. By performing the above operation in the same way in the y direction,
It is possible to output x and y coordinate data related to the coordinates that the light pen 30 contacts.

According to this embodiment, while the tablet surface is scanned once, the light pen is moved once in each of the x and y directions.
The scanning light is only detected one time at a time, and therefore, complex arithmetic processing is not required for coordinate detection, making it possible to simplify the electrical configuration and to input coordinates quickly. Also, the detection signal from the light pen is x
Alternatively, detection signals related to scanning in the y direction can be reliably distinguished, and therefore highly reliable coordinate input can be performed.

Incidentally, in the above embodiment, the case where the reflecting mirror is formed by a reflecting block having corner reflecting portions has been explained, but the present invention is not limited to this in any way, and if the same effect is achieved, A Fresnel mirror, a plane mirror, etc. may be used alone or in combination. Further, a polygon mirror may be used as the rotating mirror, and furthermore, the output data of the deflection angle detector may be corrected based on the timing of incidence on the sensors 36 and 37 to enable accurate coordinate input.
Further, it may be configured such that graphic input can be performed by moving a light pen on the surface of the tablet board.

As described above, according to the present invention, it is possible to provide an optical scanning input device with a simple configuration and capable of quickly inputting coordinates.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of a conventional optical scanning input device, FIG. 2 is an explanatory diagram of the operation of FIG. 1, and FIG. 3 is a schematic diagram showing an input section of the optical scanning input device according to the present invention. , FIG. 4 is a perspective view showing a part of the reflection block shown in FIG. 3, FIG. 5 is an explanatory diagram of the operation of FIG. 4, and FIG. 6 is an electrical configuration diagram for performing coordinate detection. 1, 13... Rotating mirror, 4, 14... Light source,
X1, X2, Y1, Y2... Fresnel mirror, 10
... Tablet board surface, 11 ... Reflection mirror as X reflection mirror, 12 ... Reflection mirror as Y reflection mirror, 30 ... Light pen, 36, 37 ...
…sensor.

Claims (1)

[Scope of Claims] 1. A light source that emits a beam of light, a rotating mirror that deflects and scans the beam of light emitted from the light source to two adjacent sides of the back side of the tablet, and a rotating mirror that deflects and scans the beam of light emitted from the light source to the two adjacent sides of the tablet. X and Y reflecting mirrors are installed along the tablet surface and reflect the incident light sent from the rotating mirror toward the tablet surface side to scan in the x and y directions, and the light pen An optical scanning input device characterized by detecting and inputting coordinates. 2. A light source that emits a beam of light, a rotating mirror that deflects and scans the beam of light emitted from the light source to two adjacent sides on the back side of the tablet, and each is equipped along the two adjacent sides of the tablet, an X, Y reflection mirror that reflects the incident light sent from the rotating mirror toward the surface of the tablet and scans in the x and y directions;
a scanning direction identification sensor provided at the starting end of two adjacent sides of the tablet;
An optical scanning input device characterized in that a light pen detects scanning light from a Y reflecting mirror and inputs coordinates.