KR20100012422A - Optical pointing device and operation method - Google Patents

Abstract

PURPOSE: An optical pointing device and an operating method thereof are provided to use arrangement of light emitting elements and light receiving elements, thereby performing cursor movement, button input and scroll operations in a small space. CONSTITUTION: A sensing unit comprises light emitting elements(12) and light receiving elements(13). A transparent cover(14) protects the light emitting elements and the light receiving elements. The transparent cover keeps a uniform distance between the elements and a subject(15). The light emitting devices and the light receiving elements are arrayed in sequence in the sensing unit. The location of the subject is recognized at a predetermined period. A cursor of a display unit moves as much as a moving distance of the recognized subject.

Description

Optical pointing device and operation method {OPTICAL POINTING DEVICE AND OPERATION METHOD}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical pointing device used as a user interface device of a personal portable terminal, and more particularly, in a small space such as a personal mobile terminal using an arrangement of light emitting and light receiving elements without a complicated optical system such as a lens module. The present invention relates to a two-dimensional optical pointing device that enables cursor movement, button input, and scroll operation of a display unit.

A typical representative optical pointing device is an optical mouse. 1 is a cross-sectional view of the optical mouse. When the light generated from the light source 2 reaches a specific portion of the cover glass 2 with the straightness through the light source guide 6, the light reflected from the object on the cover glass 2 passes through the lens 3. Noise light is filtered from the blocking film 5 and is incident on the image sensor 7 to recognize the pattern of the subject. At regular intervals, the image sensor 7 recognizes the pattern of the subject, calculates speed based on the direction and distance of the movement, and moves the cursor in the same direction by a distance proportional thereto. In addition, in order to perform an operation at a specific position of the display unit, a button prepared separately is operated. In some cases, up to two or three buttons may be provided, and a wheel may be provided to perform various operations such as a predetermined amount of scrolling.

However, such a device has a thick thickness of an imaging system, and it is difficult to employ various devices such as buttons and wheels in small and small devices such as mobile terminals. Representative conventional mobile terminals such as mobile phones utilize keypads, menu keys or function keys as an input module method, and support various functions such as phone number input or sentence creation using direction setting keys.

By the way, in recent years, it is possible to express a graphic function on the display unit of a personal portable terminal, so that it is possible to use the display unit in two dimensions as in a personal computer. Accordingly, a portable wireless information terminal having a two-dimensional pointing device for effectively using an application program using a graphical user interface (GUI) has been developed.

Korean Patent Registration No. 10-0636829 discloses an ultra-slim optical joystick using an integrated optical waveguide structure. The thickness of the imaging system is 4 mm or less, but the length thereof is increased by making the optical waveguide vertically and horizontally. Have Korean Patent Registration No. 10-0773807 discloses an optical pointing device using a diffraction grating. By using a diffraction grating, the optical diffraction grating enables optical pointing without using a complicated optical system such as a lens module or an optical waveguide. Although the light source is located between the grating and the second diffraction grating and the light reflected on the subject on the first diffraction grating is detected by the light receiving element through the second diffraction grating, the lens or the optical waveguide is not used. Relatively complex optics such as pairs will eventually be necessary and there will be limitations in reducing the thickness of the imaging system. Korean Patent Laid-Open Publication No. 10-2008-0032779 discloses an invention having an optical pointing device and a switch that performs a function by applying pressure to a light emitting portion thereof. The operation of inputting information when a pressure is applied to the switch is disclosed. However, there is a disadvantage in that the imaging system is thickened by disposing an optical system and a light source using a lens between the sensor and the light transmitting unit. Korean Patent Laid-Open Publication No. 10-2008-0000481 discloses a user input device and method using a fingerprint sensor, and sets an operation mode to a user's finger fingerprint according to a fingerprint input through a fingerprint sensor of a terminal. The user can select the operation mode that is frequently used by the user to select the set operation mode. However, it is advantageous to security by setting the operation mode only when a specific fingerprint is recognized, but it has the disadvantage that operation cannot be performed by using any subject. . Korean Patent Registration No. 10-0746874 discloses an apparatus and method for providing a service using a touch pad in a mobile terminal. Specifically, a method for implementing drag, scroll, etc. using the touch pad. The TouchPad is a small flat plate with a pressure sensor that differs in structure and basic operation from an optical pointing device. In addition, Korean Patent Registration Publication No. 10-2007-0001923 discloses a portable terminal equipped with an optical pointing device and a pointing method using the optical pointing device. When the cursor is moved to the area including the displayed scroll area, an icon and There is a way to scroll through the list, and there is a way to include additional buttons to move the icon when the button is clicked or to return to the cursor movement mode.

The above method requires an optical device such as a lens, an optical waveguide, and a diffraction grating in the case of an optical pointing device, which adds cost and has difficulty in assembly and fabrication. In addition, the touchpad is implemented to activate an operation by a button function of a mouse or to scroll a window screen like a wheel. However, the portable terminal has a small space for providing additional buttons or wheels, such as a mouse. For such a button operation, the above-mentioned document 3 is provided with a switch operated by pressure in the lower part of the optical pointing device, but there is a problem that the thickness becomes thick. As such, an object of the present invention is to provide an optical pointing device which can be applied to a portable terminal and which can perform a button input operation or a scrolling operation using only the optical pointing device without additional buttons or switches. It is done.

In order to achieve the above object, a structure of an optical pointing device according to an aspect of the present invention alternately arranges a light receiving and light emitting element on a substrate, and a transparent cover is mounted at a predetermined height. If the light receiving element acts as a noise due to a predetermined level of light when the light other than the light reflected by the light source is outside or no subject is added, an optical filter may be added to remove the noise light under the transparent cover. Alternatively, the optical filter layer may be formed on the bottom surface of the transparent cover to be used integrally. The light source passes through the transparent cover according to a predetermined radiation angle and then reflects back to the subject and then passes through the transparent cover and then enters the light-receiving element. When the light source is reflected from the same area of the same subject, the light source generates the same amount of light current. It should have a light output density pattern. In addition, the light receiving element should be disposed to cover as much as possible the surface other than the light source. In order to reduce the area of the light receiving element, a pattern such as a Fresnel lens may be put on the bottom surface of the cover glass so that light is reflected from each side by the subject and then incident on the light receiving element having a predetermined area. have.

As described above, the present invention generally utilizes an array of light-emitting and light-receiving elements having certain characteristics without complex optical systems such as a lens module required for an optical pointing device. Two-dimensional optical pointing in space, and can be a specific operation according to time, such as an input operation, a scroll movement in which the screen moves in proportion to the amount of movement of the subject in contact with the transparent cover, or a scroll movement in which the screen moves by a certain amount at a time. .

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention. 2 is a schematic side cross-sectional view showing the structure of an optical pointing device according to an embodiment of the present invention. An arrow indicates a path passing through the transparent cover 14 through the light emitting device 12, reflected from the subject 15 in contact with the transparent cover, and then transmitted through the transparent cover 14 to be incident on the light receiving device 13. When the light of the luminous flux, which is inversely proportional to the square of the transmittance of the transparent cover having a predetermined emission angle generated in the light emitting element and the light receiving sensitivity of the light receiving element, reaches the transparent cover, light is transmitted and emitted into the air when there is no subject such as a finger. . If the subject is in contact with the transparent cover to reflect light of a predetermined level or more and a light current of a predetermined level or more is generated in each light receiving element, it is confirmed that the subject is in contact with the cursor on the display device.

The arrangement distance S between the elements and the height T of the transparent cover from the transparent substrate are adjusted so that the luminous flux of the light emitting element covers and covers the transparent cover. 3, the cross section of the radiation pattern of the light emitting element required for the optical pointing device is shown in polar coordinates. One scale of radiation originating from the centrifugal circle, which is the origin of the semicircle, is represented by an angle of 10 degrees, and one scale represented by the small semicircle to the large semicircle is represented by 0.2 intervals as a relative value of the radiation density. In FIG. 3, the highest emission light density is located at an emission angle of about 15 degrees. The radiation angle with the highest emission light density is adjusted to a predetermined angle according to the manufacturing method and purpose. The radiation light density according to the radiation angle of the light source is such that the light of the light source passes through the transparent cover, the reflectance reflected by the subject, the light transmittance passes through the transparent cover, and reaches the light receiving element and enters the surface of the light receiving element. In consideration of the incident rate, the product must generate a constant photocurrent according to the emission angle of the light source, and therefore the light source must be radiated at a light flux density equal to the reciprocal ratio thereof. 3 covers 150 degrees in both directions when the range of radiation angle is 75 degrees in one direction. At this time, the ratio of the length in the lateral direction to give a uniform level of received current to height is 2 * tan (150 degrees) = 7.5. Therefore, if the thickness of the substrate is 0.1 mm, the height of the light source is 0.6 mm, the thickness of the transparent cover is 0.2 mm, and the length of one side of the optical pointing device is 15 mm, the height of the space is 15 mm / { Since (3-1) * 7.5} = 1.0mm is required, the overall optical pointing device can be made very thin, 0.1 + 0.6 + 1.0 + 0.2 = 1.9mm.

When the light reflected by the subject is incident on the light receiving element, when the subject is small, it is possible to recognize that the photocurrent is generated only in the specific light receiving element, so that the subject is positioned at the position. However, when the subject is similar to or larger than the size of the light receiving element, photocurrent occurs in one or more light receiving elements. At this time, the center position of the subject can be obtained as follows. For the purpose of explanation, in an embodiment, as shown in FIG. 5, when the transparent cover is divided into predetermined areas and nine light receiving elements having the same 3 × 3 corresponding to the respective areas are arranged, j, k = 1, 2, 3, the photocurrent I (j, k) generated in each light-receiving element corresponding to the two-dimensional index of (j, k) is detected and the photocurrent at each position is subtracted by the smallest photocurrent I _m . By multiplying the value of the position and dividing it by the sum of the photocurrent differences, the center position of the subject can be determined. When the position of the subject is expressed by an equation, equations 1 and 2 are obtained. That is, assuming that the center positions of the divided surfaces of the transparent cover are each (x _j , y _k ), the position x and y coordinates of the subject can be obtained as follows.

(식 1)

(Equation 1)

(식 2)

(Equation 2)

This value corresponds to the center of gravity coordinates obtained by multiplying the position of the center of the transparent cover determined by the spatial coordinates (x _j , y _k ) by the element I (j, k) from which the noise photocurrent I _m is removed. To implement this, a comparator or a multiplier can be used on a circuit, or after an AD (analog-digital) conversion, it can be implemented through a calculation in a microcomputer. By using this method, the center position of the subject higher than the accuracy of arrangement of the light receiving elements can be obtained.

The light source to be used can be both infrared and visible light, and in particular, in order to generate a light receiving current only in the infrared light, an optical filter for blocking the wavelength of light except for the infrared light can be used. However, as described above, when the smallest value of the photocurrent generated in each light receiving element is selected to subtract the value of the photocurrent of each light receiving element, the saturation phenomenon in which the photocurrent does not increase even if the light receiving characteristic of the light receiving element increases. As long as it does not occur, noise light can be removed without an optical filter. If the radiation pattern of the light source is not the same as above, it is inaccurate to determine the position using Equations 1 and 2 above. Therefore, a problem arises in that a large number of light receiving elements must be arranged, and only the position determination of the resolution level of the position of the light receiving element can be made by determining whether one of the light enters the light receiving element or not.

In addition, in order to reduce the area of the light receiving device, a pattern based on the principle of the Fresnel lens may be inserted into the transparent cover so that the reflected light by the subject may be incident on the light receiving device having a predetermined size. 4 illustrates a case where the size of the light receiving element is small. By doing in this way, the size of a light receiving element can be made small.

Use these optical pointing devices to locate the subject and move the cursor on the display, or activate an icon at a specific location for input operation, scroll the screen, or adjust the window screen or line by a certain amount. You can implement scrolling behavior.

First, an operation for initializing the cursor on the screen so that the cursor appears at a specific position on the display screen or a previous memory position is performed unconditionally when the portable device is placed in the cursor movement mode when there is no optical filter. If the subject is not in contact with the cover glass when using the optical filter, if the light reflected by the light source is below a certain level, the optical pointing device is not initialized immediately even if the portable device is placed in the input mode, and the subject is not in the cover glass. If the light that is contacted and reflected by the light source is above a certain level, a cursor appears on the display and the optical pointing device is initialized. If you do not want to be initialized to the cursor movement mode without the optical filter, you can specify the level of noise light so that the subject is in contact with the transparent cover so that it is initialized only when the light generated from the light source is further received.

The optical pointing device basically calculates the position of the subject at regular intervals by using Equations 1 and 2 above. In an embodiment, assume that the period updates the position of the subject every 1/1000 second. At this time, while the subject is in contact, the position one cycle before is stored, and when the state without the subject is detected, the center position of the last periodic state in which the subject is in contact is stored. As described above, the cursor of the display unit is moved by multiplying a coordinate of the position of the center of the previous subject with the position of the center of the current subject by a predetermined number to perform the optical pointing operation. Here too, of course, the accuracy of the operation is increased by increasing the number of arrays of light receiving elements.

As an embodiment for performing the button input operation, when the center position of the subject is updated by Equation 1 and Equation every 1 cycle (1/1000 sec.) As described above, if the subject is not in contact, it is 100 to 200 cycles. (100/1000 seconds to 200/1000 seconds), the x- and y-coordinates fall within a predetermined range compared to the previously memorized center of the subject, or accurately calculated by Pythagorean theorem. If it is within a predetermined range from the center position of the subject, it recognizes the same position in consideration of the error, and performs an operation of performing an icon or program of a specific position as a button operation.

According to an embodiment of the present invention, if the subject is in contact with the subject, the position of the subject is the center of the subject in consideration of the error as described above from the coordinates corresponding to the position (x ₃ , y ₁ ) of the center of the lower right region of the transparent cover. As a method of determining whether the positions coincide, if it is recognized that the position of the subject has been touched for a predetermined time, such as 500 cycles (500/1000 seconds), for example, 500 seconds (500 cycles) is changed. / 1000 seconds), if you move the center position by touching or non-contacting the subject until the subject is not approached for a certain time, the window of the display screen goes up or down instead of moving the cursor on the display. Scroll action to move left or right. If the subject does not touch for 500 cycles (500/1000 seconds), it exits the scroll mode and automatically moves the cursor to the moving mode.

The method of operation such as scrolling the screen only by a certain amount when the wheel of the mouse is rolled up or down is a predetermined distance from a specific area such that the position of the center of the subject is the position (x ₂ , y ₁ ) of the light receiving element on the bottom center side. If the contact is maintained within 500 cycles (500/1000 seconds), the mouse is switched to the wheel mode, and the position is touched non-contacted by the button method, and when it touches, the scrolling operation moves down a certain amount each time. If the subject does not touch for 500 cycles (500/1000 seconds), it exits the scroll mode and moves the cursor to the moving mode automatically. If the position of the center of the subject is to be kept in contact for 500 cycles (500/1000 seconds) within a predetermined distance in a specific area such as the center position of the transparent cover (x ₂ , y ₃ ) in order to scroll upward, When the wheel mode is switched to the non-contact or contacted position by the button method, a certain amount of scrolling is performed at this time.

The above embodiments are merely exemplary, and various modifications and equivalent other embodiments may be made by those skilled in the art. Therefore, the true technical protection scope of the present invention will be defined by the technical details of the invention described in the claims below.

1 is a schematic cross-sectional view of an optical mouse which is a conventional optical pointing device.

Figure 2 is a schematic cross-sectional view of the optical pointing device according to an embodiment of the present invention.

Figure 3 is an embodiment of the radiation pattern of the light emitting device for implementing the optical pointing device in the present invention.

Figure 4 is an embodiment of the transparent cover formation of the present invention for reducing the area of the light receiving element.

FIG. 5 is a view showing an array of light emitting and receiving elements and index coordinates for explaining the operation of the optical pointing device of the present invention; FIG.

<Description of the symbols for the main parts of the drawings>

1: optical mouse, 2: cover glass, 3: lens, 4: light emitting diode,

5: barrier film, 6: light source guide, 7: image sensor.

12: light emitting element, 13: light receiving element, 14: transparent cover, 15: subject (finger).

21: The position of the subject before a certain time, 22: The position of the current subject.

S: distance between a light emitting element and a light receiving element.

P: size of light receiving element, L: size of light emitting element.

T: distance from the substrate of the optical pointing device to the transparent cover.

Claims (12)

An optical pointing device for locating a subject in contact with a transparent cover through which a light source passes through a mobile device to move a pointer of a display unit, the optical pointing device comprising: a substrate for supporting and electrically connecting a sensing unit on which a light emitting element and a light receiving element are continuous; And a transparent cover configured to determine whether or not the contact is detected by the sensing unit by keeping the protection of the elements and the distance of the subject constant. The optical pointing device according to claim 1, wherein the sensing unit has an array of light emitting elements and light receiving elements in order. The light emitting device of claim 1, wherein the light output density according to the radiation angle is transmitted to the subject from the light emitting device according to the radiation angle, and the light emitting element is reflected from the subject of the transparent cover and then passed from the subject to the light receiving element again. And a radiation pattern inversely proportional to the product of the transmittance of the transparent cover and the sensitivity of the light receiving element. The optical pointing device according to claim 1, wherein the horizontal (x) and vertical (y) coordinates of the center of the subject are calculated to be expressed by the following Equations 3 and 4. Equation 3 and Equation 4 are as follows, and (x _j , y _k ) are the coordinates of the jth center in the x direction and the kth center position in the y direction of I divided into M horizontal and N vertical sections of the transparent cover. (j, k) is the light-receiving current of the light-receiving element corresponding to the section, and I _m is the minimum value of the light-receiving currents sampled at one period of time throughout the light-receiving element. However, M is the horizontal direction number of a light receiving element, and N is the vertical direction number of a light receiving element.

(Equation 3)

(Equation 4) The optical pointing device of claim 1, wherein the position of the subject is recognized at predetermined intervals, and the cursor is moved to move the cursor of the display unit in proportion to the recognized movement distance of the subject. The optical pointing device of claim 1, wherein the position of the subject is recognized at predetermined intervals, and the cursor is moved to move the cursor of the display unit in proportion to the recognized movement speed of the subject. The light of claim 1, wherein a pattern using a Fresnel lens principle is formed on a lower surface of the transparent cover so that the reflected light by the subject on the transparent cover is incident on a predetermined small light receiving element. Pointing device. The optical pointing device according to claim 1, wherein an optical filter is formed on a lower surface of the transparent cover to prevent light other than a light source from transmitting. The method of claim 1, wherein the subject enters the scroll operation mode when the subject comes into contact with a specific area (lower right corner) of the transparent cover for a predetermined time. And moving the cursor in proportion to the position of the subject on the transparent cover after a predetermined time, and exiting the scroll operation mode and entering the cursor movement mode when the contact is not made for a predetermined time. The method of claim 1, wherein the subject enters an operation mode that scrolls up or down by a certain amount when the subject comes into contact with another specific area of the transparent lid (middle of the lower side or the middle of the upper side) for a predetermined time. And a scrolling operation by a predetermined amount when the button is operated. The optical pointing device according to claim 1, wherein a menu is displayed when the subject is in contact with another specific area (bottom left corner) of the transparent cover for a predetermined time. The optical pointing device of claim 1, wherein a button operation is performed when the subject is not in contact for a predetermined time and then touches again.

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