TOUCH PANEL PROVIDING TACTILE FEEDBACK IN RESPONSE TO VARIABLE PRESSURE AND OPERATION METHOD THEREOF

• US 20140111480A1
• Filed: 09/03/2013
• Published: 04/24/2014
• Est. Priority Date: 10/19/2012
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: KIM, Young Sung, Kyung, Ki-Uk, Park, Suntak, Park, Bong Je, Yun, Sung Ryul, Lee, Han Saem, Choi, Mi Joeng
• Granted Patent: US 9,323,328 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 2203/04109 FTIR in optical digitiser, i.e. touch detection by frustrating the total internal reflection within an optical waveguide due to changes of optical properties or deformation at the touch location
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen

Abstract

A touch panel according to an embodiment of the present invention includes: a pressure detection unit including a light-source unit configured to generate an optical signal, an optical waveguide configured to transfer the optical signal, a sensing unit contacting with the optical waveguide to receive the optical signal according to an intensity of pressure applied externally, and a light-receiving unit configured to receive the optical signal transferred through the optical waveguide from the sensing unit; and an actuator contacting with the pressure detection unit to cause a deformation of a material according to the pressure intensity, wherein the actuator provides a tactile feedback through a vibration according to the pressure intensity.

Claims

1. A touch panel comprising:

a pressure detection unit configured to receive a first optical signal in response to pressure applied externally and detect location information or pressure intensity according to an intensity of the received first optical signal; and

an actuator contacting with the pressure detection unit to cause a deformation of a material in proportion to the pressure intensity,

wherein the actuator provides a tactile feedback through a vibration according to the pressure intensity.

2. The touch panel of claim 1, further comprising a substrate for supporting the pressure detection unit and the actuator.

3. The touch panel of claim 1, wherein the pressure detection unit comprises:

a light-source unit configured to generate an optical signal;

an optical waveguide configured to transfer the optical signal;

a sensing unit contacting with the optical waveguide to receive a second optical signal through the optical waveguide in proportion to the pressure applied externally; and

a light-receiving unit configured to receive the first optical signal transferred through the sensing unit,

wherein the pressure detection unit is formed of a material that is transparent and is deformable by the pressure applied externally.

4. The touch panel of claim 3, wherein the location information and the pressure intensity are detected according to the intensity of the first optical signal received in the light-receiving unit.

5. The touch panel of claim 3, wherein the sensing unit comprises:

a lower layer having at least one groove; and

an upper layer disposed on the lower layer and forming a projection part through the groove.

6. The touch panel of claim 5, wherein the lower layer is formed of a material having a lower refractive index than that of the optical waveguide, and the upper layer is formed of a material having a higher refractive index than that of the optical waveguide.

7. The touch panel of claim 6, wherein a contact area between the projection part formed in the upper layer and the optical waveguide varies with the intensity of the pressure applied externally.

8. The touch panel of claim 1, wherein the actuator comprises an electronic unit for generating a driving voltage according to the pressure intensity.

9. The touch panel of claim 8, wherein the actuator deforms in response to the driving voltage generated in the electrode unit.

10. The touch panel of claim 9, wherein the electrode unit is formed of a transparent and flexible material.

11. A method of operating a touch panel applied in an electronic device, the method comprising:

detecting pressure intensity or location information from a received first optical signal, the first optical signal being transferred through an optical waveguide;

applying a driving voltage to an actuator according to the detected pressure intensity;

deforming the actuator according to the applied driving voltage; and

providing a tactile feedback through a vibration in response to the deformation of the actuator.

12. The method of claim 11, wherein the sensing unit contacting with the optical waveguide receives a part of a second optical signal according to a touch input applied externally.

13. The method of claim 11, wherein the deforming of the actuator comprises:

determining the driving voltage to be applied to the actuator according to the detected pressure intensity; and

supplying the driving voltage to an electrode unit provided to the actuator.