SENSING DEVICE OF SURFACE ACOUSTIC WAVE TOUCH PANEL

• US 20090079709A1
• Filed: 09/20/2007
• Published: 03/26/2009
• Est. Priority Date: 09/20/2007
• Status: Abandoned Application

• Current Assignee: eGalax_eMPIA Technology Inc.
• Original Assignee: eGalax_eMPIA Technology Inc.
• Inventors: YEH, SHANG-TAI, HSIEH, TENG-WEI
• Application Number:
  US11/858,392
• Publication Number:
  US 20090079709A1
• Time in Patent Office: Days
• US Class Current: 345/177
• CPC Class Codes: G06F 3/0436 in which generating transducers and detecting transducers are attached to a single acoustic waves transmission substrate

Abstract

Described is a sensing device of a surface acoustic wave (SAW) touch panel having a new reflector columns and rows arrangement. As compared to the conventional design in the art where each of the reflector columns and rows are arranged from thinness to thickness, each of the arrangements of the reflector columns and rows herein is composed of a plurality of uniformly disposed reflectors having several sub-reflectors isolated with a gap or gaps. In this manner, a vibration wave transmitted through each of the reflector columns or rows can be reflected and then collected at a target transducer in an uniform pattern with respect to each portion of each of the reflecting columns and rows, thereby avoiding the problem encountered in the prior art.

Claims

1. A sensing device of a surface acoustic wave (SAW) touch panel, comprising:

a transparent substrate taking a substantially rectangular shape, having a screen area and a reflecting area, and having a first X-axis and a second X-axis substantially parallel therewith and a first Y-axis and a second Y-axis substantially parallel therewith, the first and second X-axis and Y-axis each having two ends;

a first X-axis transducer and a second X-axis transducer disposed at the reflecting area on the two ends of the first X-axis, respectively, and a first Y-axis transducer and a second Y-axis transducer disposed at the reflecting area on the two ends of the first Y-axis, respectively; and

a first Y-axis reflecting unit, a second Y-axis reflecting unit, a first X-axis reflecting unit and a second X-axis reflecting unit, disposed on the reflecting area along the first X-axis, the second Y-axis, the first X-axis and the second X-axis, respectively, each of the first and second Y-axis reflecting units including a first number of reflectors and each of the first and second X-axis reflecting units including a second number of reflectors, wherein each reflector of the first and second X-axis and Y-axis reflecting units has a gap or gaps, so as to form a plurality of sub-reflectors therein.

2. The sensing device as claimed in claim 1, wherein each of the first and second X-axis and Y-axis reflecting units has an equal distance between two neighboring reflectors thereof.

3. The sensing device as claimed in claim 1, wherein the gap between the neighboring sub-reflectors of each reflector of the first and second X-axis and Y-axis reflecting units is dependent upon a material forming the first and second X-axis and Y-axis reflecting units, a relationship among the gaps of the sub-reflectors of the neighboring reflectors of the first and second X-axis and Y-axis reflecting units is also dependent upon the material forming the first and second X-axis and Y-axis reflecting units, and a relationship among the gaps of the sub-reflectors of the reflectors of the first and second X-axis and Y-axis reflecting units is determined by experiment.

4. The sensing device as claimed in claim 1, wherein each of the reflectors in each of the first and second X-axis and Y-axis reflecting units is a reflecting line layer.

5. The sensing device as claimed in claim 4, wherein the reflecting line layer is an ink layer printed on the transparent substrate.

6. The sensing device as claimed in claim 5, wherein the transparent substrate is a transparent glass substrate.