Transparent touchpad with flat panel display for personal computers

• US 5,952,998 A
• Filed: 01/15/1997
• Issued: 09/14/1999
• Est. Priority Date: 01/15/1997
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Compaq Computer Corporation (HP Inc.)
• Inventors: Clancy, Kevin F., Holehan, Steven D.
• Primary Examiner(s): Powell, Mark R.
• Assistant Examiner(s): Kovalick, Vincent E.
• Application Number:
  US08/784,101
• Time in Patent Office: 972 Days
• Field of Search: 345/156, 345/157, 345/104, 345/173, 345/176, 361/681, 361/686
• US Class Current: 345/173
• CPC Class Codes: G06F 1/1616 with folding flat displays, e.g. laptop computers or notebooks having a clamshell configuration, with body parts pivoting to an open position around an axis parallel to the plane they define in closed position
• CPC Class Codes: G06F 1/1692 the I/O peripheral being a secondary touch screen used as control interface, e.g. virtual buttons or sliders
• CPC Class Codes: G06F 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures

Abstract

A personal computer includes a flat panel or LCD display for displaying computer status information. The display includes an overlying transparent touchpad. When the touchpad is touched, appropriate signals are processed so that movements of the user'"'"'s finger on the touchpad can be indicated by displaying altered images on the display that correspond to the movement of the user'"'"'s finger. In this way, the user gets an immediate visual feedback through the LCD display of what changes can be or have been made by touchpad control.

Claims

1. A touchpad for a personal computer comprising:

a substantially transparent substrate having upper and lower surfaces;

a series of nontransparent conductive traces formed on the upper and lower surfaces of said substrate to form an array operable to capacitively sense a location of an object placed in proximity to the substrate, said traces having a series of capacitive elements arranged along said traces, said capacitive elements being shaped to have a length along said traces which is substantially greater than their width measured transversely to the length of said traces; and

a display, situated beneath said substrate so as to project a image upwardly through said substrate to enable a computer user to visualize said image, said image being arranged so as to substantially avoid interference from said capacitive elements.

2. The touchpad of claim 1 wherein said display is a liquid crystal display.

3. The touchpad of claim 2 including a substantially transparent layer situated on top of said substrate.

4. The touchpad of claim 1 wherein said elements are diamond shaped.

5. The touchpad of claim 1, wherein said display is comprised of light emitting diodes.

6. The touchpad of claim 1, wherein the image arranging includes positioning and shading said image.

7. A touchpad for a personal computer comprising:

a substantially transparent substrate;

an array of conductive traces formed on the upper and lower surfaces of said substrate;

wherein said conductive traces include a series of capacitive elements arranged along said traces to allow finger position to be capacitively determined;

wherein said capacitive elements have a length along the traces which is substantially greater than their width measured transversely to the length of said traces;

wherein the aspect ratio of said elements is greater than 2; and

a flat panel display situated beneath said substrate so as to project images upwardly through said substrate to enable the computer user to visualize said images, said conductive traces being adapted to allow the user'"'"'s finger to be located in response to user proximity said traces being arranged so as to permit the image produced by the display to be viewed by the user.

8. A personal computer, comprising:

a microprocessor and memory for controlling the operation of said computer;

a housing containing said microprocessor and memory;

a touchpad attached to said housing and coupled to said microprocessor, comprising;

a substantially transparent substrate; and

a series of nontransparent conductive traces on an upper and lower surface of said substrate to form an array operable to capacitively sense a location of an object placed in proximity to the substrate, said traces having a plurality of capacitive elements positioned along said traces, each capacitive element being shaped to have a length along said traces substantially greater than its width measured transversely to the length of said traces; and

a display situated beneath said touchpad, coupled to said microprocessor, and operable to project an image, said image being arranged to project through said touchpad without substantial interference from said capacitive elements.

9. The computer of claim 8 including a substantially transparent layer situated on top of said substrate.

10. The computer of claim 8 wherein said elements are diamond shaped.

11. The computer of claim 8 wherein said display is a liquid crystal display.

12. The personal computer of claim 8, wherein said display is comprised of light emitting diodes.

13. The personal computer of claim 8, wherein the image arranging includes positioning and shading said image.

14. A personal computer comprising:

a microprocessor and memory for controlling the operation of said computer;

a housing containing said microprocessor and memory;

a flat panel display on said housing connected to said microprocessor, said flat panel display including a substantially transparent touchpad, said touchpad situated on top of said display, said touchpad including a substantially transparent substrate and an array of conductive traces formed on the upper and lower surfaces of said substrate, wherein said conductive traces include a series of capacitive elements arranged along said traces to allow finger position to be capacitively determined, wherein said capacitive elements have a length along the traces which is substantially greater than their width measured transversely to the length of said traces, wherein the aspect ratio of said elements is greater than 2, said touchpad being adapted to convert proximity with said touchpad into signals indicative of the position of the user'"'"'s finger on said touchpad.

15. A method for controlling the operation of a personal computer by monitoring various status information, said method comprising the steps of:

forming a series of nontransparent conductive traces on an upper and lower surface of a substantially transparent substrate;

forming a series of capacitive elements along said traces, said capacitive elements being shaped to have a length along the traces of at least twice their width measured transversely to the length of the traces;

positioning said substrate over a display; and

arranging images for said display to project in such fashion that said images substantially avoid interference from said capacitive elements.

16. The method of claim 15, wherein the step of forming conductive traces includes forming a series of parallel traces on an upper surface of the substrate and forming a series of parallel traces on the lower surface, the upper surface traces being substantially perpendicular to the lower surface traces, the upper and lower surface traces together forming an array of apertures for passing the image in an orthogonal direction through the substrate.

17. The method of claim 16 including the step of determining the position of a user'"'"'s finger on said touchpad using said traces.

18. The method of claim 15, wherein said display is a liquid crystal display.

19. The method of claim 15, wherein the display is formed with at least one light emitting diode.

20. The method of claim 15, wherein the image arranging step includes positioning and shading said image.