JPH0412844B2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an optical mouse.

(Prior art) Conventional optical mouse, for example, patent application No. 120426/1986
The mouse disclosed in the issue is a mouse that optically detects line patterns provided on two planes separated by a distance.The line pattern of the mouse pad used in this type of mouse is optically detected. A detectable line group, for example, a line group of a thin aluminum vapor-deposited film that reflects light, is configured as a line group provided on two surfaces of a transparent base material such as acrylic resin orthogonally.

A light source that emits light toward the mouse pad and a light receiving element that detects light reflected from the lines of the mouse pad are incorporated inside the mouse that moves around on a single plane according to the above configuration.

The lines formed from the aluminum vapor-deposited thin film reflect light strongly, and it is therefore possible to optically distinguish between those areas and areas where there is no line, where the reflection of light is weak, so the mouse is sensitive to the intensity of the light it receives. A corresponding change in the electrical signal is detected to identify the line.

(Problems to be Solved by the Invention) The line pattern of the mouse pad according to the conventional configuration described above is formed by, for example, a vacuum evaporation method.

This is a method in which a mask with holes in a line pattern is brought into close contact with a transparent substrate, and aluminum is evaporated to form a predetermined line pattern on the surface of the substrate.

By this method, a line pattern with high dimensional accuracy can be obtained.

However, the vacuum evaporation method requires a considerable amount of time for evacuation because the transparent substrate is placed in a vacuum chamber and the vapor deposition operation is performed after the evacuation operation.
There is a problem of low production efficiency.

In addition, the size of the transparent substrate used as a mouse pad is, for example, 180 mm x 230 mm, so in order to put a large amount of such a large substrate into the tank and to ensure uniform quality of the deposited thin film, a very large container is required. A vacuum evaporation device with a tank is required.

For these reasons, the conventional mouse pad described above requires a long manufacturing process and expensive manufacturing equipment, resulting in a problem of high manufacturing costs.

Furthermore, as the transparent base material used in the mouse pad, an expensive synthetic resin material such as acrylic resin is used from the viewpoint of ease of processing, light weight, safety, etc., so there is a limit to cost reduction.

(Means for Solving the Problems) An object of the present invention is to provide a mouse that solves the problems of the above-mentioned optical mouse and is inexpensive to manufacture.

In order to achieve the above object, the optical mouse according to the present invention has optically detectable line patterns provided on substantially the same plane.

Further, the line patterns are configured in different directions, one line pattern that specularly reflects light and the other line pattern that diffusely reflects light.

Then, each line pattern is distinguished and detected using a mouse pad based on the difference in the intensity of reflected light in each line pattern.

That is, a first line pattern that can be detected optically and a first line pattern for detecting a direction is formed by a specular reflection surface that specularly reflects light and a diffuse reflection surface that diffusely reflects light. the second detectable
a mouse pad having a second line pattern formed by a high diffuse reflection surface and a low diffuse reflection surface having relatively different diffuse reflectances, an irradiation light source for illuminating the mouse pad; It is characterized by comprising a line pattern reading device including a specular reflection light receiving element that receives specularly reflected light from the specularly reflecting surface and a diffusely reflecting light receiving element that receives the diffusely reflected light from the diffusely reflecting surface.

(Example) The principle of the optical mouse according to the present invention will be explained with reference to FIGS. 2 to 6.

Generally, how light irradiated onto a certain surface is reflected depends on the surface condition of that surface.

For example, light reflected from a mirror surface that is said to be shiny or glossy is strong, and as the law of reflection indicates, the reflection takes place at a reflection angle that is the same as the angle of incidence.

Such reflection is called specular reflection. By the way,
In FIG. 2 illustrating an example of regular reflection, the angle θ that the incident light 2 and the regularly reflected light 3 make with respect to the normal 0-0 on the mirror surface 1 is equal, and the intensity of each of these lights is also equal.

On the other hand, on a non-glossy surface, such as a surface of paper or wood, light is scattered and no specular reflection occurs as on the mirror surface. Such a dull surface has the property of reflecting light little by little in all directions. Light incident at a certain angle is reflected with a substantially conical (Gaussian distribution) intensity distribution with a rounded tip that is biased in the direction of the reflection angle and includes a slight specular reflection component. Such reflection is called diffuse reflection.

An example of diffuse reflection will be explained with reference to FIG. In the figure, reference numeral 4 indicates a paper-like surface as a diffuse reflection surface, and when this surface is irradiated with incident light 2, diffuse reflection occurs, and the intensity distribution of diffuse reflection light 8 is indicated by reference 5. The distribution becomes bell-shaped.

Here, on the paper surface where diffuse reflection occurs,
Try to form thin lines at appropriate intervals where specular reflection can occur.

As the thin wire, for example, a strip of polyester film (thickness 0.07mm) cut into a width th1 (=0.5mm)
~0.1mm) on the paper with an interval th2 (=0.5mm).

In this case, since the line surface of the polyester film is smooth and almost mirror-like, regular reflection occurs on the surface of the film.

The above example will be explained with reference to FIG. Number 6 in the figure
7 represents a paper whose surface is a diffuse reflection surface, and numeral 7 represents a polyester film whose surface is a mirror surface.

Here, the surface reflectance of the polyester film 7 due to the incident light 2 is approximately 6%.

This value defines the refractive index of the polyester film as n
= 1.66, and was calculated using the surface reflectance equation (1-n/1+n) ² .

Therefore, when light reflection occurs on the front and back surfaces of the polyester film 7, the reflectance per film is 6%×2=12%. This shows that the component of specularly reflected light 3 is about 12% of the incident light 2.

On the other hand, on the surface of the paper 6 without the polyester film 7, the incident light 2 is diffusely reflected and diffusely reflected light 8 is generated.

However, the reflectance component in the specular reflection direction is considerably smaller than the specular reflectance on the polyester film 7.

Therefore, if a suitable light-receiving element is placed in the direction in which the specularly reflected light comes, when the specularly reflected light is incident on the light-receiving element, a current corresponding to the amount of light will flow, and when the diffusely reflected light is incident, the current will flow. A corresponding current flows.

However, since the difference in light amount between the two is quite large, this difference in light amount can be determined by an electric circuit as a difference in current value. In other words, the lines formed by the polyester film 7 with an interval t (=0.5 mm) can be recognized.

Next, a method for determining lines on a diffuse reflection surface such as paper will be explained with reference to FIGS. 5 and 6.

For example, suppose that the entire original surface of the paper 6 shown in the figure is white.
The black line of TH1 (=0.5mm) is spaced TH2 (=0.5mm)
mm). The white part of the line pattern formed in this manner is indicated by reference numeral 9, and the black part is indicated by reference numeral 10.

When light is irradiated onto the surface of the paper 6, even if the angle of incidence of the incident light 2 is the same, the amount of reflected light will differ depending on whether the irradiated area is on a black line or a white line.
The latter outweighs the former.

This is because, in general, black has the property of absorbing light, and white has the property of reflecting light, and a diffuse reflection surface also has the same property. Therefore, for the same amount of incident light, the diffusely reflected light from the white portion appears strong, and the diffusely reflected light from the black portion appears weakly.

Incidentally, the magnitude of the reflected light component in the direction perpendicular to the plane of the paper in FIG. It appears smaller than the size of the reflected light component in the direction perpendicular to the plane of the drawing.

Therefore, if a light-receiving element that can detect reflected light is placed at an appropriate position, the black line on the white paper will be the difference in light intensity from the part without this line, that is, the part of the white paper (white line), that is, the current value on the electric circuit. It can be distinguished as the difference between Based on the output of the light receiving element, it is possible to recognize the black portions 10 on the white paper 6 at intervals of 0.5 mm.

The method for recognizing black and white areas described above is applied to an optical mouse.

A mouse is a device that controls the position of a cursor on a computer's CRT, and must accurately convert two-dimensional movements.

Therefore, it is necessary to distinguish and recognize the line pattern on the horizontal axis (x-axis) and the line pattern on the vertical axis (y-axis). Therefore, a mouse pad is constructed using the above-mentioned recognition method.

For example, as shown in FIG. 7, a first line pattern indicating the first direction (x-axis direction) appears on the surface of the white paper 6 between the transparent lines 7L that are the specular reflection surface and these transparent lines 7L. A second line pattern indicating the second direction (the y-axis direction perpendicular to the above x-axis) is formed by a line that is a diffuse reflection surface and a second line pattern indicating the second direction (the y-axis direction perpendicular to the above x-axis). If it is composed of a white line 9L and a black line 10L which is a low diffuse reflection surface, it can function as a mouse pad.

Embodiment 1 (See FIGS. 1, 7 to 12B) In FIGS. 7 and 8, a black line 10L, which is a low diffuse reflection surface, is placed on the surface of white matte paper 6.
is printed in the y-axis direction. As a result, white lines 9L, which are highly diffuse reflective surfaces, are inevitably formed alternately with black lines 10L.

The size of the paper 6 is, for example, about 200 mm x 250 mm, but the size is not limited to this size.

The material of the paper 6 is not particularly limited, but it is desirable that it be easy to print, have a uniform surface condition, and easily cause diffuse reflection. The thickness must be such that it is difficult to bend.

The printed black line 10L has a line width of 0.5
mm, and print in parallel in the y-axis direction with an interval of 0.5 mm.
These line widths and intervals are appropriate in terms of cursor control accuracy, but are not limited to these dimensions.

The black ink for printing is desirably made of a material that has as great an absorption characteristic as possible for the wavelength of light emitted from an LED (light emitting diode) used as a light source for illuminating the mouse pad constructed as in this example.

Note that an infrared LED (emission wavelength: 950 mm) is suitable for the LED used as the light source, as it causes less deterioration in luminous efficiency.

Then, on the paper with line 10L printed,
A transparent line 7L that causes regular reflection (specular reflection) along the x-axis direction perpendicular to the line 10L.
will be established.

The line width and spacing of this line 7L are 0.5 mm each, the same as the black line 10L. A transparent film such as the aforementioned polyester film is used as the material for the line 7L that causes this specular reflection, and this film is adhered with a transparent adhesive.
Another method is to print in lines with what is generally called a "glossy varnish", which is transparent and produces gloss on the printed surface, which is used on magazine covers and the like.

This film must be transparent to the wavelength of the light emitted from the LED, which is the light source.

Next, the mouse pad 10 configured as described above will be explained.
An optical system for detecting the 0 line will be explained.
In FIG. 1 illustrating the arrangement of various members constituting this optical system, reference numeral 11 is an LED as an irradiation light source that irradiates the mouse pad 100, and reference numeral 12 is an LED.
A lens that focuses the light from the LED 11 onto the surface of the mouse pad. Reference numeral 13 is a diffuse reflection light receiving element for receiving and detecting the light that is diffusely reflected from the diffuse reflection surface of the mouse pad. Reference numeral 14 is a diffuse reflection light receiving element that effectively diffuses the diffuse reflection light. a lens that focuses light on the reflective light-receiving element 13;
Reference numeral 15 indicates a specular reflection light receiving element for receiving and detecting light specularly reflected from the specular reflection surface of the mouse pad, and reference numeral 16 indicates a lens that effectively condenses the specularly reflected light onto the specular reflection light receiving element 15. . Here, the LED 11 is set so that its optical axis is inclined with respect to a vertical line drawn on the mouse pad 100.

Each of these members is fixedly arranged inside the mouse with an appropriate positional relationship designed such as the mounting angle and the distance between each member. Of course, each lens is designed to function most effectively in terms of size, focal length, aberration, etc. It should be noted that in each of the explanatory drawings, the thicknesses of the black line 10L and the transparent line 7L are emphasized for convenience of explanation.

Next, the optical system built into the mouse shown in FIG. 1 is attached to the mouse pad 100 shown in FIGS. 7 and 8.
The method for detecting each line will be explained.

In FIG. 1, light emitted from an LED 11 is focused onto the surface of a mouse pad 100 by a lens 12. The size of the condensing area is preferably a spot with a diameter of 0.5 to 0.8 mm, which is sufficient to brightly illuminate one line.

Light from LED 11 is reflected by the surface of mouse pad 100. As described above, this reflection occurs as regular reflection on the transparent line 7L and as diffuse reflection on the surface of the paper 6.

Since the light is specularly reflected on the transparent line 7L, this reflected light passes through the lens 16 and is received by the specular reflection light receiving element 15. Then, a current corresponding to the amount of light received flows through the specular reflection light receiving element 15.

Here, when the light irradiation part is on the transparent line 7L, the white line 9 below this line
Among the diffusely reflected light from the L and black lines 10L, the component in the specular reflection direction overlaps the reflected light from the transparent line 7L. However, the transparent line 7
Since the diffusely reflected light from the surface of the paper 6 is considerably smaller than the specularly reflected light from L, the specularly reflected light has little effect on the current.

In FIG. 9, when the mouse moves diagonally across the transparent line 7L from point A (time t=t1) to point X (time t=t2) on the mouse pad, light is emitted from the LED 11 during that time. The spot moves to a part where there is no transparent line 7L.
Diffuse reflection occurs in this part. Then, the component in the specular reflection direction of the diffusely reflected light passes through the lens 16 and is received by the specular reflection light receiving element 15 .

Since this diffusely reflected light is considerably smaller than the specularly reflected light on the transparent line 7L, less current flows through the specularly reflected light receiving element 15 than when the reflected light is received on the transparent line 7L.

By the way, there is a white line 9 on the surface of the paper 6.
Since there are the L and black lines 10L, a change corresponding to the difference in the amount of diffusely reflected light between white and black appears as the output of this light receiving element. However, since this amount of change is small compared to the specularly reflected photocurrent from the transparent line 7L, it does not affect the large change in current that corresponds to the presence or absence of the transparent line 7L.

Changes in the current flowing in accordance with the amount of light incident on the specularly reflected light receiving element 15 are processed by an electronic circuit, and the signal waveform converted into a change in voltage is shown in FIG. 10b.
Shown below.

In FIG. 10b, large voltage changes (indicated by broken lines) corresponding to the presence or absence of the transparent line 7L, and changes corresponding to the presence or absence of the white line 9L and black line 10L on the surface of the paper 6 result in ripples. ).

If this change in analog signal is converted into a digital signal using a circuit (for example, a hysteresis comparator) with TU and TL as threshold values, the 10th
As shown in Figure b, the ripple disappears and the line 7 becomes transparent.
Only the presence or absence of L can be extracted as a signal. That is, the specular reflection light receiving element 15 detects only the line in the y-axis direction.

On the other hand, the light reflected on the surface of the paper 6 is diffusely reflected with an intensity distribution such that it is strong on the white line (see FIG. 5) and weak on the black line (see FIG. 6). This diffusely reflected light also includes a component perpendicular to the plane of the paper. This vertical component is also reflected largely on the white line and small on the black line.

As explained in FIG. 1, since the lens 14 and the diffuse reflection light receiving element 13 are arranged at a position perpendicular to the paper surface, the vertical component of the diffuse reflection light passes through the lens 14 and is received by the diffuse reflection light receiving element 13. .
Therefore, a current flows through the diffuse reflection light-receiving element 13 that changes in accordance with the difference in the amount of reflected light from the white line and the black line.

This current is considerably smaller than the current corresponding to the specularly reflected light on the transparent line 7L. However, if the number of amplification stages of the amplifier circuit connected to the diffuse reflection light receiving element 13 is made larger than the number of amplification stages of the specular reflection light receiving element 15, the final signal levels of both can be made to be the same.

By the way, as the mouse moves, the point A1 of the mouse pad 100 (time t=
While the spot of light emitted from the mouse moves from point t3) to point V (time t=t4), the spot may be located on the transparent line 7L.

As described above, specular reflection occurs on the transparent line 7L, and the specularly reflected light enters the specular reflection light receiving element 15 and is converted into a signal for identifying the presence or absence of the transparent line 7L.

However, since this specularly reflected light component does not go in the direction perpendicular to the plane of the paper, the diffuse reflection light receiving element 13
It will not cause malfunction by entering the

On the other hand, the light transmitted through the transparent line 7L is
The light reaches the white part of the image and is diffusely reflected. Therefore, if the thickness of the transparent line 7L is uniform, the diffusely reflected light will be the fifth
The light is reflected with an intensity distribution having a substantially similar shape to that shown in FIGS. Strictly speaking, when light passes through the transparent line 7L and exits, the amount of light decreases by about 6%, so the diffusely reflected light that passes through the transparent line 7L is smaller than the diffusely reflected light from the area without the transparent line 7L. few.

Therefore, regardless of the existence of the transparent line 7L, a current flows through the diffuse reflection light receiving element 13, which corresponds to the difference in light amount between the white line and the black line.

A waveform obtained by converting this change into a voltage change signal using an electronic circuit is shown in FIG. 12b. In the figure, reference numeral 17 indicates ripples caused by the presence or absence of the transparent line 7L. Further, FIG. 12b shows a signal waveform converted into a digital signal using a hysteresis comparator with TU1 and TL1 as threshold values. Therefore, it can be seen that the diffuse reflection light receiving element 13 detects only the line in the x-axis direction.

As described above, the mouse according to the present example can distinguish and count the line patterns in the x-axis and y-axis directions on the mouse pad 100, so that the position of the cursor can be accurately controlled.

Example 2 (See Figures 13 and 14) The mouse of Example 1 moved around in contact with a printed mouse pad surface. Therefore, with use, the line pattern gradually wears out, and there is a risk that the mouse pad will eventually lose its function as a mouse pad.

If the mouse pad 100 in Example 1 can be manufactured at a very low cost, it can be considered a practical mouse pad since it can be treated as a disposable mouse pad.

However, even if it is a disposable mouse pad, it is desirable that the mouse pad has as long a lifespan as possible, so an example of producing a mouse pad with such a long lifespan will be described.

In this example, the mouse pad 10 in Example 1 is
The structure is such that a transparent plate is further provided on top of the transparent plate.

This transparent plate is suitably, for example, an acrylic resin plate with a thickness of about 1 mm or a polyester film with a thickness of about 0.2 mm. As shown in FIG. 13, this transparent plate 2
0 may be simply placed on the mouse pad 100 with an air layer in between. Of course, if they are overlapped, the transparent plate mouse pad 100 will be misaligned, so
As shown in the figure, glue a portion of width TH3 (= about 10 mm to 15 mm) inward from the outer edge of the mouse pad 100 with adhesive 2.
1, the adhesive is bonded all around the circumference. The thickness of the adhesive is preferably about the same as the thickness of the transparent line 7L that specularly reflects. Note that in the drawings, dimensions in the thickness direction are emphasized for convenience of explanation.

The detection method when the transparent plate 20 is placed will be explained.

In FIG. 13, when light 22 enters the transparent plate with 100% light intensity, light 23 is reflected at the surface with 4% light intensity. Therefore, on the front and back sides of the transparent plate 20, the light 24
In addition to the 4% light amount in , 8% of the light amount is generated as reflected light. This phenomenon is a transparent line 7
This affects when detecting the specularly reflected light of L.

For example, the total amount of specularly reflected light from a spot on the transparent line 7L is determined by the reflectance of the line surface plus the reflectance of the front and back sides of the transparent plate 20, so that the light 23,
The total amount of light 24 is 8%, and 5.1% of the amount of light 25 that is transmitted back and forth through the transparent plate 20 and emitted before and after being reflected on the line surface is added, resulting in a light amount of 13.1%.

Incidentally, the above 5.1% is a value obtained by multiplying the transmission loss (0.92×2) at the transparent plate 20 by 6% of the reflectance at the transparent line 7L.

On the other hand, when the spot falls outside the transparent line 7L, there is no regular reflection from the paper surface, so the light 26 is
Despite the incident light intensity of 100%, the transparent plate 20
The total light amount of each reflected light 27 and 28 from the front and back sides is 8%.

Therefore, the amount of specularly reflected light incident on the specularly reflected light-receiving element 15 varies between 8% and 13.1%, and the signal waveform associated with the change in the amount of light is the waveform shown in FIG. 10b in Example 1. It will be the same.

Therefore, if the threshold values TU and TL are appropriately determined, the signal as shown in FIG. 10 can be converted into a digital signal as shown in FIG. .

Next, when the diffusely reflected light from the black line 10L and white line on the paper passes through the transparent plate 20, 8% of the light amount is lost due to reflection, so 92
%, the shape of the intensity distribution of the reflected light and the ratio of the difference in light amount from the black line 10L and the white line remain unchanged. Therefore, as in the first embodiment, it is possible to detect lines related to diffusely reflected light.

The above method can extend the life of the mouse pad 100. In this embodiment, in order to improve the abrasion resistance of the transparent plate 20, a transparent plate may be provided with a hard film generally called a hard coat on the mouse pad contact surface of the mouse.

Providing this transparent plate will further extend the life of the mouse pad.

In the mouse pad used in this embodiment, there must be a layer of air between the transparent plate 20 and the surface (black line, white line printed surface) of the paper 6 serving as the base material of the mouse pad. The reason for this is that if a transparent adhesive material or the like is interposed between the transparent line 7L and the transparent plate 20, the difference in refractive index will become smaller, and the reflectance in this area will drop from 13.1% to 8%. This is because it becomes impossible to determine. Therefore, the transparent plate 20 is bonded only to the outer periphery of the paper 6.

Example 3 (See FIGS. 15 and 16) Even if the transparent line 7L in Example 1 is provided on the back side of the transparent plate 20 in Example 2, a mouse pad having the same function as that in Example 2 can be obtained. I can do it.

The present example relates to such an embodiment.

However, in this case, the reflectance of the transparent line 7L must be higher than the reflectance of the transparent plate 20.
The reason is that there is no air layer between the transparent plate 20 and the transparent line 7L, so the transparent line 7L
This is because unless the reflectance of the transparent line 7L is higher than the outer reflectance of 8%, it will be difficult to distinguish the line.

As a means for increasing the reflectance of the transparent line 7L portion, there is a method of depositing the portion using a vacuum evaporation method.

According to this method, the reflectance of the line can be changed arbitrarily.

FIG. 15 illustrates an example of this, in which an aluminum vapor-deposited thin film 30 is formed on the outer surface of the polyester film 7 that constitutes the transparent line 7L, making the entire film semitransparent. Therefore, hereinafter, this line will be referred to as a vapor deposition film line 30L.

In this example, in order to reduce the influence on the diffusely reflected light from the paper surface below, the vapor deposition film line 30L is
The reflectance was set to 20%. Therefore, when the light 30 with 100% light intensity is incident as shown in FIG. 17, the reflected light 31 is 24%, which is the sum of the 4% reflectance of the transparent plate 20 and the 20% reflectance at the vapor deposition film line 30L. The light is incident on the specular reflection light receiving element 15 with a reflectance of .

In addition, the amount of light is
With respect to 100% of the incident light 32, the reflected light 33 is emitted with a reflectance of 8% on the front and back sides of the transparent plate 20.

Therefore, the difference in light amount depending on the presence or absence of the vapor deposition film line 30L is 24% and 8%, and the lines can be distinguished. In addition, as another means of obtaining the 20% reflectance line achieved by the vapor deposition film line 30L, according to the content disclosed in Japanese Patent Application No. 1983-27713,
It is also possible to configure a line with a reflectance of 20% by adjusting the area ratio between a minute element pattern with high reflectance and the remaining light-shielding portion of this element pattern.

On the other hand, for the diffusely reflected light generated on the surface of the paper 6,
The existence of the vapor deposition film line 30L affects the recognition of the white line and the black line.

That is, when there is a spot on the vapor deposition film line 30L, 100-24-24=52%, and when there is a spot outside the vapor deposition film line 30L, it is 100-4-24.
Diffuse reflected light decreases to 4=92%.

Therefore, as shown in FIG. 16, a ripple 170 due to the vapor deposition film line 30L is added to the output signal waveform of the diffuse reflection light receiving element 13 that receives the diffuse reflection light from the white line, black line 10L, etc. on the paper surface. .

This ripple 170 appears larger than the ripple 17 in FIG. 12a. However, the threshold TU3 for converting into a digital signal,
Digital signal conversion is possible by appropriately setting the level of TL3.

For the above reasons, the mouse pad in this embodiment also functions as a mouse pad in the same manner as in the first embodiment.

The transparent plate 20 in this embodiment can also be configured as an acrylic plate or a polyester film with a hard coat layer provided on the surface that comes into contact with the mouse. As in Example 2, it is appropriate to adhere the transparent plate 20 and the paper pad base material at the outer peripheral edge of the mouse pad.

In order to prevent the mouse pad from slipping on the desk during mouse operation, it is necessary to take measures to prevent slipping, such as interposing a thin rubber plate between the bottom surface of the pad base and the desk top surface. Furthermore, in this example as well, the patent application
- As disclosed in No. 106115, aluminum vapor deposited thin film 30
In order to prevent glare, it is desirable to use a transparent plate that is colored in a way that allows infrared light of the LED emission wavelength to pass through but blocks visible light.

Embodiment 4 (See FIGS. 17 to 21) The above-described embodiments 1 to 3 had a structure in which a specular transparent transparent line was superimposed on a diffuse reflection surface.

In contrast, this embodiment has a configuration in which specularly reflective black minute portions and white minute portions, and diffusely reflective black minute portions and white minute portions are provided on the same plane.

That is, a black or white part with a very smooth surface and a glossy surface and a black or white part with a matte surface and almost no gloss are provided on the same plane by, for example, printing. As already explained, specular reflection occurs in glossy black and white parts.

Here, the black pigment has the property of absorbing light, and the white pigment has the property of reflecting light. Therefore, even on the same glossy surface, a difference in intensity of reflected light due to difference in pigment color and a slight diffusely reflected component are superimposed on specularly reflected light between black and white, resulting in an intensity distribution of reflected light.

These intensity distributions are shown in FIG. 17 for the specularly reflective white part C and in FIG. 18 for the specularly reflective black part D, respectively, as distributions in the regions shown by broken lines. In each figure, reference numeral 31 indicates incident light, and reference numeral 32 indicates reflected light.

Next, the diffuse reflective black and white parts are shown in Example 1.
is set up in the same way as. These intensity distributions are shown in FIG. 19 for the diffusely reflective white area A and in FIG. 20 for the diffusely reflective black area B, respectively, as distributions in the areas indicated by broken lines.

These four portions A, B, C, and D are arranged as a set of minimum pattern elements 35 as shown in FIG. Then, the parts C, D, arranged in the y-axis direction
The combination of C, D... becomes a specular reflection line, and the combination of adjacent portions A, B, A, B... forms a diffuse reflection line.

Therefore, if the specular reflection light receiving element 15 for detecting the x-axis direction is arranged in the mouse as shown in FIG.
Strong reflected light is obtained from the lines of parts C, 2, H, 2, etc., and only weak reflected light comes from the lines of parts A, B, A, 2, etc., so the specular reflection light receiving element 15 is used for the lines of parts C, 2, etc. , portions A and B can be distinguished based on the difference in light amount, and position detection in the x-axis direction becomes possible.

In this case, the difference in the amount of reflected light between parts C and D and the difference in the amount of reflected light between parts A and B are added to the output signal of the light-receiving element as ripples, but if the threshold value is selected appropriately, it can be read as in the previous embodiment. There will be no error.

On the other hand, regarding position detection in the y-axis direction, the combination of parts A, C, A, C, etc. becomes a white line with a high intensity of diffusely reflected light, and the combination of parts B, B, B, N, etc.
A combination of these results in a black line with low intensity of diffusely reflected light.

Therefore, in the x-axis direction, the diffusely reflecting white lines and black lines are arranged alternately in Example 1, and the diffusely reflecting light-receiving element 13 in FIG. It becomes possible to detect black lines.

In this case, the difference in light intensity between parts A and B and the difference in light intensity between parts B and D are added to the output signal of the light receiving element as ripples, but since the differences are small compared to parts A and H lines, parts B and N lines, hysteresis If the threshold value of the comparator is selected appropriately, reading errors will not occur.

In addition, in this embodiment, when constructing the mouse pad, the above-mentioned FIG. 13 for pattern protection,
It is desirable to provide a protective transparent plate in accordance with the configuration explained in FIG. 14.

Example 5 (See FIG. 22) Each of the examples described so far combined one light source and two light receiving elements.

In contrast, this embodiment uses two light sources and one light receiving element.

In this embodiment, as shown in FIG.
A, 11B and one light receiving element 135 are placed above the mouse pad 70.

This mouse pad 70 may be any of the mouse pads described in Examples 1 to 4. Reference numerals 42, 44, and 46 each indicate a condenser lens.

In this example, the light source 11A and the light source 11B are used by being turned on alternately. When the light source 11A is turned on, reflected light having different intensity distributions in the specular reflection direction is generated from the specular white and black portions and the diffuse white and black portions, respectively, as described above.

Here, since the amount of light from the specular reflective line is greater than the amount of light from the diffuse reflective line, the light receiving element 135 allows the specular reflective line and the diffuse reflective line to be distinguished.

On the other hand, when the light source 11B lights up, the light receiving element 1
35 receives only the diffuse reflection component directed toward the element 135. Therefore, only the black and white colors of the diffuse reflective line can be distinguished from each other based on the difference in light amount.

The electronic circuit for processing the electrical signals of this optical system is slightly more complex than in the first to fourth embodiments. That is, it is necessary to determine that a specular reflective line is being detected when the light source 11A is lit, and that a diffuse reflective line is being detected when the light source 11B is lit. However, it is technically possible, for example, by synchronizing the lighting time of the light source and the operating time of the light receiving element using a circuit.

(Effects and Functions of the Invention) According to the present invention, paper, which is easy to process, poses no particular danger, and is inexpensive, can be used as the base material for the mouse pad, and a line pattern can be formed on it by simple means such as printing paper. Therefore, it is possible to provide an optical mouse simply and at low cost.

[Brief explanation of drawings]

Figures 1 and 22 are diagrams explaining the optical system arrangement of the mouse, Figure 2 is a diagram explaining specular reflection on a mirror surface, and Figure 3 is a diagram explaining the state of diffuse reflection on a non-specular surface. Figure 4 is a diagram explaining an example of forming a transparent line, Figure 5 is a diagram explaining the intensity distribution of diffusely reflected light on a white surface, and Figure 6 is a diagram explaining the intensity distribution of diffusely reflected light on a black surface. FIG. 7 is a partial front view of the mouse pad, FIG. 8 is a partial cross-sectional view of the same as above, FIGS. 9 and 11 are diagrams explaining the trajectory of the mouse on the mouse pad, and FIG. 10a is a signal waveform diagram showing the output of a specular reflection light receiving element that receives specularly reflected light in response to the movement of the mouse, Figure 10b is a waveform diagram obtained by digitally converting the signal in the same figure as above, and Figure 12a is a waveform diagram showing the output of the specular reflection light receiving element that receives specularly reflected light in response to the movement of the mouse. FIG. 12b is a signal waveform diagram showing the output of the diffuse reflection light-receiving element which received the diffuse reflection light accordingly.
is a waveform diagram obtained by digitally converting the signal shown in the above figure, Figure 13 is a diagram explaining the optical path in a mouse pad with a transparent plate placed on it for surface protection, and Figure 14 is a cross-sectional view explaining the adhesion state of the transparent plate in the same figure. , FIG. 15 is a cross-sectional view of a mouse pad with specular reflective lines formed on the back surface of a transparent protective plate, FIG. 16 is a signal wave diagram showing the output of a diffuse reflection light-receiving element when the reflectance of the transparent line is large, and FIG. Figure 17 is a light intensity distribution diagram in a specularly reflective white area, Figure 18 is a light intensity distribution diagram in a specularly reflective black area, Figure 19 is a light intensity distribution diagram in a diffusely reflective white area, and Figure 20 is a diagram of the light intensity distribution in a specularly reflective white area. 21 is a light intensity distribution diagram in a diffusely reflective black part, and FIG. 21 is an explanatory diagram of a line pattern formed by a combination of minute parts having different reflection characteristics. 7L...Transparent line, 30L...Vapor deposited film line, 9L...White line, 10L...Black line, 11...LED, 13...Diffuse reflection light receiving element, 15...Specular reflection light receiving element.

Claims (1)

[Claims] 1. A first line pattern for detecting an optically detectable first direction is formed by a specular reflection surface and a diffuse reflection surface that performs diffuse reflection, while optically detecting the first line pattern. A mouse pad is provided in which a second line pattern for detecting a possible second direction is formed by a high diffuse reflection surface and a low diffuse reflection surface having relatively different diffuse reflectances, and irradiation is applied to the mouse pad. An optical mouse comprising: a light source; a line pattern reading device including a specular reflection light receiving element that receives specularly reflected light from the specularly reflecting surface; and a diffusely reflecting light receiving element that receives diffusely reflected light from the diffusely reflecting surface.