KR20100035968A - Optical pointing device and portable terminal having the same - Google Patents

Abstract

PURPOSE: An optical pointing device and a portable terminal with the same are provided to remove a lens system which needs accurate alignment and a large space. CONSTITUTION: A light source(160) applies light with coherence to an object surface. An image sensor(170) receives light scattered from the object surface. The image sensor converts the received light into an electrical image signal. The image sensor outputs the converted image signal. A controller receives the image signals from the image sensor. The controller calculates displacement of a speckle pattern showing the image signals according to movement of the object.

Description

Optical pointing device and portable terminal having the same {OPTICAL POINTING DEVICE AND PORTABLE TERMINAL HAVING THE SAME}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an input device of a portable terminal, and more particularly, to an optical pointing device that supports a user to move a pointer or perform a click operation on a screen through the movement of a finger.

As high-speed portable Internet services such as wireless broadband (WiBro) become popular, the need for a pointing device such as a mouse for a computer is increasing in portable terminals such as mobile phones and personal digital assistants (PDAs).

Korean Patent Publication No. 2006-94066 (pointing device with a built-in photo matching filter) invented by Ju Sung-chul and published on August 28, 2006 includes: a light source for emitting light; A lens unit for guiding light emitted from the light source to an object surface and condensing the light reflected from the object surface to a sensor unit; A sensor unit for sensing light reflected from the object surface and focused through the lens unit; And a light matching filter for removing the stray light flowing into the sensor unit.

However, since such a conventional optical pointing device has a large volume, there is a problem of inhibiting the slimming of a portable terminal. As in the above patent, the optical pointing device using the lens portion has to maintain the distance between the objective surface, the lens portion and the sensor portion to a certain size or more, and because the volume of the lens portion itself is large, it is difficult to miniaturize. Moreover, in the case of further including a switch for a click action in such an optical pointing device, its volume becomes more problematic.

Therefore, there is a need for an optical pointing device capable of simultaneously implementing a pointing function and a click function with a minimized volume.

According to an aspect of the present invention, there is provided an optical pointing device and a portable terminal having the same that can implement a pointing function and a click function with a minimized volume.

An optical pointing device according to an aspect of the present invention, the light source for irradiating the surface of the object with coherent light; An image sensor which receives light scattered from the surface of the object, converts the received light into an electrical image signal, and outputs the converted light; And a controller configured to receive image signals from the image sensor and calculate displacement of speckle patterns appearing on the image signals according to the movement of the object.

According to another aspect of the present invention, a portable terminal includes a light source for irradiating light having coherence to an object surface, an image for receiving scattered light from the object surface, and converting the received light into an electrical image signal and outputting the image. An optical pointing device having a sensor; A display unit which displays an image according to the input image data on a screen; And a controller configured to receive image signals from the optical pointing device, calculate displacement of speckle patterns appearing on the image signals according to movement of the object, and output image data according to the calculated displacement result to the display unit. do.

The optical pointing device and the portable terminal having the same according to an aspect of the present invention detect the object movement through the displacement of the speckle pattern according to the roughness of the object surface, thereby eliminating the lens system requiring precise alignment and large space. This has the advantage that the volume and manufacturing cost of the optical pointing device or portable terminal can be reduced and the assembly efficiency can be improved.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention; In describing the present invention, detailed descriptions of related well-known functions and configurations are omitted in order not to obscure the subject matter of the present invention.

1 is a cross-sectional view showing an optical pointing device according to a preferred embodiment of the present invention. The optical pointing device 100 includes a button 110 including a housing 110, a substrate 120 and a cover 130, an image sensor 170, and a light source. source 160, stud 150, and switch circuit 180.

The housing 110 has a generally open top cylindrical shape, and includes a base portion 112 in the form of a disc and a side wall 114 extending upwardly in a direction substantially perpendicular to the edge of the base portion 112.

The substrate 120 is accommodated in the housing 110 and has a generally open top cylindrical shape, a base portion 122 having a disc shape, and a sidewall extending upwardly in a direction perpendicular to an edge of the base portion 122. 124 and a cylindrical projection 126 protruding downward from the base 122. The substrate 120 is disposed in the housing 110 such that the lower end of the protrusion 126 is spaced apart from the base 112 of the housing 110.

The cover 130 is accommodated in the housing 110 and has a generally circular cap shape, and has a disc shaped base portion 132 and a downward direction in a generally perpendicular direction from an edge of the base portion 132. An extended sidewall 136 and a hole 134 formed in a central portion of the base 132. The side wall 136 is spaced apart from the outer circumference of the base 132 at predetermined intervals, and the hole 134 is provided with a transparent window 140. The side wall 124 is fitted around the side wall 136 of the cover 130 such that the inner surface of the side wall 124 and the outer surface of the side wall 136 of the cover 130 are in close contact with each other. The combination of the substrate 120 and the cover 130 (ie, the button) moves integrally.

The image sensor 170 is accommodated in a space inside the buttons 120 and 130, and is mounted on the base 122 of the substrate 120. The image sensor 170 has a light receiving circuit 172 exposed on its top surface, which receives light scattered from the surface of the finger 10 in contact with the window 140. It is arranged to face directly to the window 140 to receive. As the image sensor 170, a charge-coupled device (CCD) image sensor, a complementary metal-oxide semiconductor (CMOS) image sensor, or the like may be used.

The stud 150 is accommodated in a space inside the buttons 120 and 130, has a generally round rod shape, and is mounted on the base 122 of the substrate 120. The stud 150 has an upper surface 152 that is inclined at a predetermined angle with respect to the base 122.

The light source 160 is accommodated in a space inside the buttons 120 and 130 and is mounted on the inclined top surface 152 of the stud 150. The light source 160 outputs light having coherence, and the light source 160 is aligned such that its optical axis faces the window 140. As the light source 160, a conventional laser diode capable of outputting coherent light may be used. For example, a vertical cavity surface emitting laser (VCSEL) commonly referred to as a bicell may be used. .

The switch circuit 180 is accommodated in a space between the buttons 120 and 130 and the base 112 of the housing 110, is disposed on the base 112 of the housing 110, and a printed circuit board. (printed circuit board: PCB, 182) and dome sheet (186).

The printed circuit board 182 includes a conductive contact member 184 formed on an upper surface thereof, and the contact member 184 constitutes a switch together with the dome 188. In addition, the switches 184 and 188 are axially aligned with the protrusion 126. At this time, the axis alignment means that the central axes of each other are aligned to coincide with each other.

The dome sheet 186 is attached to an upper surface of the printed circuit board 182 and includes a conductive dome 188 having a hemispherical shape, and the dome 188 completely covers the contact member 184.

The optical pointing device 100 outputs a click signal or an image signal according to a user's manipulation.

When the user presses the buttons 120 and 130 with the finger 10, the buttons 120 and 130 move downward, and the protrusion 126 presses the dome 188. The pressed dome 188 is in electrical contact with the contact member 184, and the printed circuit board 182 outputs a click signal generated by the electrical contact.

When the user touches the finger 10 with the window 140 and the coherent light output from the light source 160 is irradiated on the finger 10 of the user, the rough surface of the finger 10 Light scattered at is incident on the light receiving circuit 172. In the image detected by the image sensor 170, an interference pattern, which is viewed as irregular spots called a speckle pattern, is formed.

2 is a diagram illustrating an image detected by the image sensor 170. Referring to FIG. 2, it can be seen that bright and dark pixels form an interference pattern that is seen as irregular spots. As an overview of the interference phenomenon, when the coherent light output from the light source 160 is incident on the surface of the finger 10, one of the light receiving circuits 172 may be caused due to the step of the surface of the finger 10. The light rays incident on the pixels have different light paths. When such a path difference corresponds to an integer multiple of the wavelength of light, constructive interference occurs, and when an integer multiple + 0.5 times, destructive interference occurs. The surface of every object has some degree of step, and if these steps are not very small relative to the wavelength, speckle pattern by the surface occurs.

When the user moves the finger 10 while the finger 10 is in contact with the window 140, the speckle pattern detected by the image sensor 170 also moves. The present invention determines the pointing displacement intended by the user by measuring the moving direction and the moving distance (ie, displacement) of the speckle pattern.

3 is a view for explaining the displacement of the speckle image according to the movement of the finger. FIG. 3A shows an image detected before finger movement, and FIG. 3B shows an image detected after finger movement. Referring to FIG. 3A, it can be seen that a specific pixel constituting the speckle pattern is located at a1 on the x axis and b1 on the y axis. Referring to FIG. 3B, it can be seen that the specific pixel constituting the speckle pattern moves from the position a1 on the x axis to the position a2 as the finger moves, and there is no change in position on the y axis. In other words, it can be seen that as the finger moves, the entire speckle pattern is moved by 2 pixels in the -x axis direction.

4 is a diagram illustrating a portable terminal having the optical pointing device illustrated in FIG. 1, and FIG. 5 is a diagram illustrating a main circuit configuration of the portable terminal 200 illustrated in FIG. 4.

Referring to FIG. 4, a display unit 210, a keypad 220, and the like are disposed on a front surface of the portable terminal 200, and the optical pointing device 100 is located together with the keypad 220. The front surface of the display unit 210 is disposed below.

Referring to FIG. 5, the portable terminal 200 includes a keypad 220, an optical pointing device 100, an image signal processor (ISP) 230, a display unit 210, and a controller 240. do.

The keypad 220 provides keys for inputting numeric and text information and function keys for setting various functions, and outputs a key signal S1 generated by a user to the controller 240.

The optical pointing device 100 outputs the click signal S2 from the switch circuit 180 generated by the user's finger press to the controller 240, and the image signal S3 from the image sensor 170. Is output to the image signal processor 230.

The image signal processor 230 processes the image signal S2 input from the optical pointing device 100 in units of frames, and temporarily stores the processed image frame.

The controller 240 calculates the displacement of the speckle pattern by reading and comparing the image frames S4 stored in the image signal processor 230, and moves a cursor on the screen according to the calculated displacement result. Image data for controlling the display unit 210 may be output.

The display unit 210 displays an image according to the image data input from the controller 240 on the screen. As the display unit 210, a conventional liquid crystal display including a liquid crystal unit and a backlight unit for irradiating light to the liquid crystal unit may be used.

The optical pointing device according to the present invention may be variously modified depending on whether or not the stud is used, the position and shape of the stud, the position of the light source, and the like. In the following modifications of the present invention, the same reference numerals are used for the same elements, and overlapping descriptions will be omitted.

6 to 8 are views showing various modifications of the optical pointing device according to the present invention.

6 is a view showing a first modification of the optical pointing device according to the present invention.

The top surface 152a of the stud 150a mounted on the base 122 of the substrate 120 is parallel to the base 122, and the light source 160 is mounted on the top surface 152a of the stud 150a. do. Since the light source 160 has a predetermined divergence angle, the optical axis of the light source 160 does not necessarily have to be aligned to face the window 140, but the light source 160 does not have to be aligned within the divergence angle of the light source 160. At least part of it needs to be located. Since the optical axis of the light source 160 does not face the window 140, the position where the light scattered from the surface of the finger 10 is concentrated also moves in the lateral direction as compared with the case of FIG. 1. To increase, the light receiving circuit 172 of the image sensor 170 is arranged to be placed in the concentrated position.

7 is a view showing a second modification of the optical pointing device according to the present invention.

The stud 150b is mounted on the top surface of the image sensor 170 and is disposed beside the light receiving circuit 172. The top surface 152b of the stud 150b is inclined with respect to the top surface of the image sensor 170, and the light source 160 is mounted on the inclined top surface 152b of the stud 150b. The light source 160 is aligned such that its optical axis faces the window 140.

8 is a view showing a third modification of the optical pointing device according to the present invention.

A flexible printed circuit board (FPCB) 150c is attached to an upper surface of the image sensor 170, a light source 160 is mounted on the flexible printed circuit board 150c, and the light source 160 is a light receiving circuit. It is disposed next to 172. The optical axis of the light source 160 does not face the window 140, but at least a part of the window 140 is positioned within the divergence angle of the light source 160.

On the other hand, in the detailed description of the present invention has been described with respect to specific embodiments, it will be apparent to those skilled in the art that various modifications are possible without departing from the scope of the present invention.

For example, although the optical pointing device 100 is illustrated as not including a control unit, the optical pointing device 100 may include a control unit as shown in FIG. 5, and in this case, the optical pointing device may be provided. The device 100 may output a pointing signal according to a user's finger movement to the portable terminal.

In addition, the pointing signal is not only used to move the cursor on the screen but may be used for various control operations such as zoom-in or zoom-out of the screen.

In addition, the optical pointing device 100 may further include elastic means for providing a restoring force to the buttons 120 and 130. For example, the optical pointing device 100 may include an elastic body such as a spring in a space next to the switch circuit 180, or Ordinary elastic means for providing a restoring force to the button, such as forming the connecting portion of the button (120, 130) and the housing may be applied.

In addition, the controller 240 may include a memory for storing data such as an operating program, or the portable terminal 200 may further include a separate memory.

1 is a cross-sectional view showing an optical pointing device according to a preferred embodiment of the present invention,

FIG. 2 is a diagram illustrating an image detected by the image sensor illustrated in FIG. 1;

3 is a view for explaining the displacement of the speckle image according to the finger movement,

4 is a view showing a portable terminal having the optical pointing device shown in FIG.

5 is a view showing the main circuit configuration of the portable terminal shown in FIG.

6 to 8 show various modifications of the optical pointing device according to the present invention.

Claims (7)

In the optical pointing device, A light source for irradiating the surface of the object with light having coherence; An image sensor which receives light scattered from the surface of the object, converts the received light into an electrical image signal, and outputs the converted light; And a controller configured to receive image signals from the image sensor and calculate displacement of speckle patterns appearing on the image signals according to movement of the object. The method of claim 1, A button to receive the light source and the image sensor; And a switch substrate disposed below the button, the switch substrate having a switch operated by pressing the button. The method of claim 2, And the button has a transparent window formed on top thereof. The method of claim 3, And a stud for tilting the light source such that the optical axis of the light source faces the window. In a portable terminal, An optical pointing device having a light source for irradiating light having coherence to an object surface, an image sensor for receiving the light scattered from the object surface, converting the received light into an electrical image signal, and outputting the light; A display unit which displays an image according to the input image data on a screen; And a controller configured to receive image signals from the optical pointing device, calculate displacement of speckle patterns appearing on the image signals according to movement of the object, and output image data according to the calculated displacement result to the display unit. Portable terminal, characterized in that. The portable terminal of claim 5, wherein the image data is data for moving a cursor on the screen. The method of claim 5, wherein the optical pointing device, A button to receive the light source and the image sensor; And a switch substrate disposed below the button and having a switch operated by pressing the button, and outputting a click signal generated by pressing the button to the controller.

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