MOBILE ELECTRONIC DEVICE HAVING CAPACITIVE SENSOR WITH REDUCED VISIBILITY ISOLATION AREAS AND CORRESPONDING METHOD

• US 20090122017A1
• Filed: 11/09/2007
• Published: 05/14/2009
• Est. Priority Date: 11/09/2007
• Status: Abandoned Application

• Current Assignee: Motorola Mobility, Inc. (Lenovo Group Ltd.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Emig, David Michael, Zhuang, Zhiming
• Application Number:
  US11/937,723
• Publication Number:
  US 20090122017A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: H04M 1/22 Illumination; Arrangements for improving the visibility of characters on dials
• CPC Class Codes: H04M 1/72442 for playing music files
• CPC Class Codes: H04M 2250/22 including a touch pad, a touch sensor or a touch detector

Abstract

A mobile electronic device and corresponding method have a user interface for receiving a touch input. The mobile electronic device includes a capacitive sensor having an electrode layer with non-etched away portions and etched away portions, and having isolation areas formed in the etched away portions, and a segmented optical shutter disposed on a side of the capacitive sensor, the optical shutter including a liquid crystal layer sandwiched between a top absorbing polarizer and a bottom absorbing polarizer, and including a reflectance increasing element disposed between the liquid crystal layer and the bottom absorbing polarizer. A reflectance of the reflectance increasing element is selected to reduce a ratio of a reflectance through the non-etched away portions to a reflectance through the etched away portions to make an appearance of the user interface substantially uniform in an off state.

Claims

1. A mobile electronic device having a user interface for receiving a touch input, comprising:

a capacitive sensor having an electrode layer with non-etched away portions and etched away portions, and having isolation areas formed in the etched away portions; and

a segmented optical shutter disposed on a side of the capacitive sensor, the optical shutter including a liquid crystal layer sandwiched between a top absorbing polarizer and a bottom absorbing polarizer, and including a reflectance increasing element disposed between the liquid crystal layer and the bottom absorbing polarizer,

wherein a reflectance of the reflectance increasing element is selected to reduce a ratio of a reflectance through the non-etched away portions to a reflectance through the etched away portions to make an appearance of the user interface substantially uniform in an off state.

2. The mobile electronic device of claim 1, wherein reflectance increasing element is a reflective polarizer.

3. The mobile electronic device of claim 2, wherein the reflective polarizer is a dual-brightness-enhancement-film (DBEF) polarizer.

4. The mobile electronic device of claim 1, further comprising a low-efficiency polarizer disposed between the liquid crystal layer and the reflectance increasing element.

5. The mobile electronic device of claim 4, wherein an efficiency of the low-efficiency polarizer is selected to impart a desired grey appearance to the user interface.

6. The mobile electronic device of claim 1, wherein the liquid crystal layer is a twisted nematic liquid crystal layer.

7. The mobile electronic device of claim 1, wherein the mobile electronic device is one of a mobile telephone, a cellular telephone, a wireless radio, a portable computer, a laptop computer, an MP3 player, and a satellite radio.

8. A method of manufacturing a mobile electronic device having a user interface for receiving a touch input, comprising:

disposing a capacitive sensor having an electrode layer with non-etched away portions and etched away portions, and having isolation areas formed in the etched away portions;

disposing a segmented optical shutter on a side of the capacitive sensor, the optical shutter including a liquid crystal layer sandwiched between a top absorbing polarizer and a bottom absorbing polarizer, and including a reflectance increasing element disposed between the liquid crystal layer and the bottom absorbing polarizer; and

selecting a reflectance of the reflectance increasing element to reduce a ratio of a reflectance through the non-etched away portions to a reflectance through the etched away portions to make an appearance of the user interface substantially uniform in an off state.

9. The method of claim 8, wherein the reflectance increasing element is a reflective polarizer.

10. The method of claim 9, wherein the reflective polarizer is a dual-brightness-enhancement-film (DBEF) polarizer.

11. The method of claim 8, further comprising disposing a low efficiency polarizer between the liquid crystal layer and the reflectance increasing element.

12. The method of claim 11, wherein an efficiency of the low-efficiency polarizer is selected to impart a desired grey appearance to the user interface.

14. The method of claim 8, wherein the mobile electronic device is one of a mobile telephone, a cellular telephone, a wireless radio, a portable computer, a laptop computer, an MP3 player, and a satellite radio.

15. An apparatus having a user interface for receiving a touch input, comprising:

a capacitive sensor having an electrode layer with non-etched away portions and etched away portions, and having isolation areas formed in the etched away portions; and

a top absorbing polarizer disposed on a side of the capacitive sensor;

a liquid crystal layer disposed on a side of the top absorbing polarizer opposite to the capacitive sensor;

a reflectance increasing element disposed on a side of the liquid crystal layer opposite to the top absorbing polarizer; and

a bottom absorbing polarizer disposed on a side of the reflectance increasing element opposite to the liquid crystal layer,

wherein a reflectance of the reflectance increasing element is selected to reduce a ratio of a reflectance through the non-etched away portions to a reflectance through the etched away portions to make an appearance of the user interface substantially uniform in an off state.

13. The method of claim 18, wherein the liquid crystal layer is a twisted nematic liquid crystal layer.

16. The apparatus of claim 15, wherein reflectance increasing element is a reflective polarizer.

17. The apparatus of claim 16, wherein the reflective polarizer is a dual-brightness-enhancement-film (DBEF) polarizer.

18. The apparatus of claim 15, further comprising a low-efficiency polarizer disposed between the liquid crystal layer and the reflectance increasing element.

19. The apparatus of claim 18, wherein an efficiency of the low-efficiency polarizer is selected to impart a desired grey appearance to the user interface.

20. The apparatus of claim 15, wherein the apparatus is one of a mobile telephone, a cellular telephone, a wireless radio, a portable computer, a laptop computer, an MP3 player, and a satellite radio.