WO2014107473A2

WO2014107473A2 - Rear mounted virtual keyboard for a tablet computer

Info

Publication number: WO2014107473A2
Application number: PCT/US2014/000001
Authority: WO
Inventors: Stephen TIBBITTS
Original assignee: Tibbitts Stephen
Priority date: 2013-01-03
Filing date: 2014-01-02
Publication date: 2014-07-10
Also published as: WO2014107473A3

Abstract

A virtual keyboard tablet computer has a conventional data display on a front side of the computer and touch sensitive data input regions on an obverse rear side thereof. The data input regions discriminate between grasping pressure applied between thumbs on the front of the device and fingertips on the rear of the device versus distinct data input pressures. The computer then translates those pressures into alpha-numeric characters for display on the data display of the tablet computer.

Description

Title: REAR MOUNTED VIRTUAL KEYBOARD FOR A TABLET COMPUTER

TECHNICAL FIELD

The invention relates to data entry apparatus for personal computers, More specifically, the invention relates to keyboards for tablet style computers.

BACKGROUND OF THE INVENTION

The personal computer has transformed the way the world does business as well as the way individuals communicate with one another electronically. Text, graphic images and other content can now be created, edited, transmitted and reviewed virtually anywhere in the world almost in real time by way of the Internet. The transformational nature of this technology is generally recognized as one of the most important economic innovations of our time. Nevertheless, content must first be entered into the personal computer before it can be reviewed by another individual. Early personal computers relied primarily on alpha-numeric data entry through the use of conventional keyboards in which depression and release of a key on the keyboard created a so-called "make code" and a "break code" correlating to an ASCII code set for numbers, characters and letters. At a later date, control of a cursor on the computer screen was controlled by a separate data input device, commonly referred to as a "mouse" which transmitted Cartesian coordinate data from a positioning device (i.e., the "mouse") to the computer. As the personal computer was modernized the liquid crystal display (hereinafter "LCD") screen replaced the cathode ray tube, and membrane and virtual keyboards replaced the mechanical keyboard. As a result, the personal computer continued to shrink in size. Eventually, the data entry terminal and data display became integrated as the tablet computer. An example of an early tablet computer manufactured and distributed by Hewlett-Packard Company, Houston. Texas, is disclosed in U.S. Patent No. 6,944,012 titled, "Tablet Computer Keyboard and System and Method Incorporating Same," issued September 13, 2005, the disclosure of which is incorporated herein by reference. That particular tablet computer/keyboard combination was marketed under the designation TC I 100 and consisted of a tablet computer having an integrated display/data entry screen. Cursor control could be effected through the use of a stylus directly on die touch sensitive LCD display screen including entry of alpha-numeric characters through a virtual keyboard on the screen or through handwriting recognition software built into the computer operating system. Alternatively, the tablet computer could be connected to a conventional mechanical keyboard having QWERTY keys as well as a Track Point^® cursor control between the "F" and "J" keys to direct the cursor on the computer screen.

The tablet computer shown in the Ό 12 patent when connected to the removable keyboard is of the so-called laptop style computer. When using the computer in this configuration, it is necessary to place the keyboard on a relatively planar, stable surface such that accurate touch typing can be achieved. Improper orientation of the user's forearms and hands relative to the keyboard results in a rapid diminution of typing accuracy and speed, thereby limiting the usefulness of laptop style computers in environments which are moving, or subject to acceleration and deceleration which destabilizes the position of the hands with respect to the keyboard. Thus, it is difficult to use the conventional laptop computer in an environment such as an airplane, a train or other common carrier. When converted to a tablet style computer, data entry is achieved by using the stylus on the touch sensitive LCD display. Displays of this type may be capacitive, resistive, optical, surface acoustic wave, bending wave touch, capacitive, etc. and one example of optical system is disclosed in U.S. Patent No. 4,928,094 titled, "Battery- Operated Data Collection Apparatus Having an Infrared Touch Screen Data Entry Device," issued May 22, 1990 to Smith, and assigned to the Boeing Company, Seattle, Washington. Regardless of the display touch sensitivity type, it is imperative that the stylus be carefully controlled on the screen whether used in a handwriting recognition mode, or on a virtual keyboard. Any jostling of the user's hand with respect to the tablet computer or vice versa will result in a inaccurate input. To alleviate this problem those of ordinary skill in the art have developed exotic data input mechanisms, such as the finger mounted data entry device disclosed in U.S. Patent No. 6,885,316 to Mehring, titled, "System and Method for Keyboard Independent Touch Typing," issued April 26, 2005. Mehring discloses a wearable glove having sensitive portions on the fingers and thumb portion thereof. The user touches the thumb with a respective finger, or finger portions to tap out a code which corresponds to conventional symbols such as alpha-numeric codes. Although such a device could overcome problems associated with relative movement of a user's hand(s) with respect to a tablet computer, such exotic devices have never achieved commercial success.

It has been recognized that by firmly grasping the tablet computer device between the fingers and thumbs of two hands, the thumbs of alternate hands can be relatively precisely located with respect to a typing surface on the device such as a conventional, miniaturized keypad. Various personal information management computers such as the device sold under the Blackberry trademark employ a real or virtual keyboard in a miniaturized form beneath the thumbs of the user. The user grasps the device with the fingers of both hands and essentially types with the thumbs only. Although such an arrangement provides increased accuracy for data input because the hands and the typing surface are relatively stabilized with respect to one another, typing speeds are significantly degraded because only the thumbs are being used.

Other prior art efforts to stabilize the user's input hand or hands are shown in Design Patent No. D348,654 to Branck, et al., titled, "Hand Held Terminal with Input Keyboard and LCD Display Touch Screen," issued on July 12, 1994, and assigned to PAR Technology Corporation, New Hartford, New York. Branck, et al. disclose a handheld terminal with input keyboard and LCD display screen in which a user's single hand is restrained against the body of a terminal having the keyboard by a strap around the back of the hand. The user's thumb is then free to operate the keyboard. Here again typing speed is limited because only the thumb is used for typing.

U.S. Patent No. 7,075,5 13 issued to Silfverberg, et al., on July 11, 2006 the disclosure of which is hereby incorporated herein by reference disclose a "Zooming and Panning Content on a Display Screen" device for displaying virtual maps and the like on a tablet type computer display. The device is fully grasped on its lateral edges by left and right hands of a user. In an alternate embodiment shown in Figures 3 and 4 of that Patent, control buttons are located on obverse rear side for zooming and panning the display. However, means for inputting alpha-numeric symbols are not disclosed.

Therefore, a need exists for a tablet type computer which can be firmly grasped by a user's hands while also providing means for rapidly entering alpha-numeric data.

A further need exists for a tablet type personal computer which is easily stabilized in the hands of a user while permitting precise, rapid input of alpha-numeric data.

BRIEF SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a tablet type computer which can be firmly grasped in a user's hands while simultaneously permitting rapid data entry of alphanumeric characters through the user's fingers.

It is a further object of the present invention to provide for a tablet computer which achieves the above object and which also does not require the user to adapt his or her fingers to specific predetermined locations on the computer for data entry.

The invention achieves the above objects, and other objects in advantages which will be apparent from the description which follows, by providing a rear mounted touch sensitive keyboard for a tablet computer. The keyboard is adapted to distinguish between a grasping action by the user, and a data input action by the user. In a preferred embodiment of the invention, the keyboard includes a housing having a front side data display area and an obverse rear side having a plurality of data input regions such that the housing can be grasped between thumbs and fingers of a user's hands. An input device, separate from the front data display is provided for differentiating between a grasping pressure of the user's fingers and an input actuating pressure applied by the fingers to the data input regions. Finally, the tablet computer is provided with a memory for mapping a sequence of different finger input pressures or the data input regions to a!pha-numeric characters for display in the data display area.

In the preferred embodiment of the invention, the data input regions may be divided into discrete left and right hand regions capable of detecting four simultaneous finger touchdown pressures from each hand when the computer is in landscape mode. The data input regions preferably permit the user to touch down his or her fingertips in freeform positions and then make determinations as to whether the applied fingertip pressures relate to merely grasping the tablet computer or whether those pressures represent data input actuations. The data input device can determine that actuating pressure by comparing relative sizes of fingertip touch downs with respect to time or by other means such as changes in capacitance, resistance, etc. The data input regions are also preferably capable of detecting and tracking fingertip translational motions such as for cursor control or the like. Common command characters may also be mapped to translational motions as well as panning or zooming commands.

In one preferred embodiment of the invention, Unified Braille Code is used for mapping the eight fingertip touchdown pressures to alpha-numeric characters as well as other common computer characters. The keyboard device may also incorporate upper and lower data input regions capable of detecting the fingertip touchdowns when the device is held in a portrait mode.

In an alternate embodiment of the invention, a single data input region is provided on the obverse rear side of the housing for detecting eight fingertip touchdowns and relative movements and pressures thereof rather than discrete data input regions. The invention may be provided with a computer program providing graphic representation on the display of the mapping sequence used by the memory to assist the user in learning a fingertip touchdown sequence used to generate the alpha-numeric codes. Non-virtual input mechanisms may also be employed in alternate embodiments. The invention includes a method of operation. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is an isometric, perspective view of a tablet computer incorporating an aspect of the present invention.

Figure 2 is a rear elevational view of the tablet computer shown in Figure 1 illustrating left and right data input regions in a landscape mode, and optional upper and lower rear data input regions for use in a portrait orientation.

Figure 3 is a high level block diagram of various elements of the device shown in

Figure 1.

Figure 4 is a detailed flow chart illustrating the sequential steps used for determining whether fingertip grasping pressures signify a data entry input or merely a grasping pressure to hold the device.

Figure 5 is a table disclosing the Unified Braille Code for fingertips of the left and right hands of a user of the device shown in Figure 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A rear mounted virtual keyboard integrated with a tablet computer is generally indicated at reference numeral 10 and the various Figures of the attached drawings wherein numbered elements of the Figures correspond to like numbered elements herein. The computer 10 includes a conventional liquid crystal diode ("LCD") display 12 for displaying text, data, video and other forms of output supported by a housing 14 of the conventional type. The tablet computer is preferably provided with a conventional cursor control device 16 such as a four-way controller, track ball, track point, touch sensitive digitizing pad or the like. An observe side 18 thereof shown in Figure 2 includes left and right side data input regions 20, 22 which are preferably located in a position such that when the tablet computer 10 of Figure 1 is grasped by the user's left and right hands fingertips of the respective hand will fall within the regions 20, 22. Data input regions may be of any suitable touch sensitive device such as optical, capacitive, resistive, surface acoustic wave, bending wave touch, etc. which are well known to those of ordinary skill in the art. An appropriate touch panel for this use is made by Cyprus True Touch, San Jose, California, Model CY3290-TMA400. Optional upper and lower data input regions 24, 26 are shown in phantom lines in Figure 2 which may be useful when the tablet computer 10 is held in a portrait orientation. Those of ordinary skill in the art will of course appreciate that a single large data input region replacing regions 20 through 26 may be provided to register touchdowns and positioning and pressure of the user's fingertips at a higher cost than having the small discrete regions shown in Figure 2. The virtual keyboard tablet computer 10 advantageously distinguishes between grasping pressure applied by fingertips of a user's hands on the data input regions, and data input actuating pressures applied by the fingers to those regions. Those of ordinary skill in the art will understand upon reviewing this disclosure that characteristic changes with respect to time representing data input actuations can be detected by various touchpad sensors regardless of the type used. One well known characteristic of an increased grasping pressure is an increased size of a fingertip touchdown area when a data input pressure is applied in contrast to mere grasping pressure. Characteristic changes with respect to surface resistivity, capacitance, opacity, etc. are also measurable by various types of type sensors. The invention advantageously uses those changes to determine whether a user is merely grasping the pad or attempting to input data. The use of relatively large regions 20-26 for data input permits the user to touch down fingertips (represented at reference numerals 29) in freeform provided that the touch down regions do not substantially overlap.

As best seen in Figure 3, the virtual keyboard tablet computer 10 is provided with a mainboard or motherboard 30 having a central processing unit 32 in the form of a microprocessor or the like in operative communication with the data input regions 20, 22, 24 and 26. The microprocessor identifies when all four fingers are grasping the tablet computer 10 and distinguishes between grasping pressures and data input pressures. If data input pressures are registered, the microprocessor outputs that information to the display 12. The tablet computer 10 is also preferably provided with^' an orientation sensor 34 to activate either the left and right touch panels or the upper and lower touch panels depending on the orientation of the computer.

A computer program suitable for use in the microprocessor executes instructions illustrated in Figure 4 of the attached drawings. In an initiating step 36, the appropriate data input region 20, 22 or 24, 26 is scanned. Cartesian coordinates and pressure information is delivered to the microprocessor in step 38 after the panel has been scanned. This sequence is repeated at least preferably 20 times per second and the microprocessor determines at step 40 whether four touchdown points indicative of a pattern of a human hand having four discrete quasi-circular patterns 29 have been detected at decision box 44. If no such pattern is detected, step 40 is repeated. If four such matching finger patters are detected then the state of those fingertip touchdowns is recorded at step 46 and compared to a previous state at step 48. If differences are detected at steps 50, 51 the microprocessor determines at decision box 52 whether the differences represent differences in location at step 54 or merely pressure at step 56. If the differences is one of location then the location difference is compared to a previous state at step 58 which is indicative of a sliding command which is matched (step 60) in the memory of the microprocessor 32 to an appropriate sliding command such as cursor movement and such sliding command is sent to the central processing unit 32 at step 62. Alternatively, at step 56 if it is determined that there is merely a pressure difference without a location difference the pressure difference is interpreted as an alpha-numeric command which is matched to a table in the microprocessor memory and a character command is sent to the central processing unit also at step 62. If any of these tests are failed, then the program is directed to step 40 in which the microprocessor determines whether four touchdown points match finger positions on each side. Thus, if each of these tests are failed, the program concludes that the user is merely grasping the device and not attempting to input data.

As best seen in Figure 5, the microprocessor in the CPU 32 preferably uses the Unified Braille Code to determine what pattern of fingertip touchdown pressure differences correspond to alpha-numeric characters as well as various punctuation codes, and function key codes recognized as part of the ASCII command set. Thus, inputting a pressure differential in the left index finger without changing pressure differentials in other touchdown fingers on the respective left and right data input regions represents the ASCII code corresponding to the Roman letter "a", whereas the capital letter "A" is represented by making data input gestures with the index fingers of each hand. In a similar way, the four fingers of each hand represent all of the alpha-numeric codes as well as various punctuation marks and function keys commonly used in association with alpha-numeric data input. The CPU 32 may provide an audible tone through a speaker (not shown) indicating that an alpha/numeric code input has been recognized.

As described above, various panning, zooming and other functions can be represented by any one of a variety of translational motions of various fingers. Translational motions can also be mapped to a variety of common command characters such as: Space Bar, Shift, Tab, Capital Lock, Enter, Backspace, Function, Control, Delete, Alternative, and the like. This will be well understood by those of ordinary skill in the art after reviewing this disclosure. The CPU 32 can have a program which graphically, displays the Unified Braille Code on the LCD display 12 allowing the user to practice matching pressure inputs on the data input regions to the Unified Braille Code display on the LCD as a training tool. Other Braille Codes, e.g., American Braille may also be employed. The program preferably provides positive feedback (visual, audible or both) for correctly performing the necessary data input pressures representative of the alphanumeric character being displayed on the LCD screen.

Those of ordinary, skill in the art will conceive of other alternate embodiments of the inventions upon review of this disclosure. For example, the data input regions 20-26 may be the discrete data display regions 20-26 shown in the Figures, or they may be subsumed in a single larger data input panel. In addition, the entire obverse side of the tablet computer 10 may be a discrete physical part attachable to any tablet computer such as by means of hook and loop closures, interference fit, and electrically communicated to a conventional tablet computer through a universal serial bus cable, or wire!essly through any protocol such as Bluetooth® or ΑΝΤ^Φ. In this way, any conventional tablet computer can be converted into a virtual keyboard tablet computer 10 of the present invention.

In a low cost, alternate embodiment (not shown) the left and right data input regions 20, 22 are replaced with eight discrete momentary membrane switches having sufficient mechanical resistance to prevent mere grasping pressure from actuating the switches. The switches preferably provide tactile or audible feedback indications that the affected switch has been actuated. In this way, a low cost device can be produced although the freeform touch down facility of the invention is forfeited. In the alternate embodiment, only eight pressure sensitive switches, four on each side of the obverse surface of the device are provided. Thus, the invention is not to be limited to the above description but is to be determined in scope by the claims which follow.

Claims

1. A rear mounted virtual keyboard for a tablet computer, comprising:

a housing having a front side data display area and an obverse rear side having a plurality of data input regions such that the housing can be grasped between thumbs and fingers of a user's hands;

input means for differentiating between a grasping pressure and an input actuating pressure applied by the fingers to the data input regions; and,

memory mapping means for mapping a sequence of different finger input pressures to alpha/numeric characters for display on the data display area.

2. The keyboard of Claim 1, wherein the data input region is divided in to discrete left and right hand regions capable of detecting four simultaneous finger touch down pressures from each hand in a landscape mode.

3. The keyboard of Claim 1, wherein the input means detects actuating pressure by comparing relative sizes of fingertip touchdowns with respect to time.

4. The keyboard of Claim 3, wherein the input means is capable of detecting and tracking a fingertip translational motion.

5. The keyboard of Claim 4, wherein the memory means maps a translational motion to one of a command sequence including common command characters.

6. The keyboard of Claim 5 wherein the common command characters are selected from the set: Space, Shift, Tab, Capital Lock, Enter, and Backspace,.

7. The keyboard of Claim 6 wherein the set further includes: Function, Control, Delete and Alternative;

8. The keyboard of Claim 1, wherein the input means is capable of detecting eight fingertip touchdowns in free form.

9. The keyboard of Claim 1 , wherein the memory means uses Unified Braille Code for mapping eight finger touch down patterns to alpha/numeric characters.

10. The keyboard of Claim 1 , wherein the data input regions are divided in to discrete upper and lower regions capable of detecting four simultaneous finger touch down pressures from each hand in a portrait mode.

1 1 . A rear mounted keyboard for a computer, comprising:

a housing having a front side data display area and an obverse rear side having a data input region such that the housing can be grasped between thumb and fingers of a user's hand;

input means for differentiating between a grasping pressure and an input actuating pressure applied by the fingers to the data input region; and, memory mapping means for mapping a sequence of different finger input pressures to alpha/numeric characters for display on the data display area.

12. The keyboard of Claim 1 1 , wherein the data input region is located on one side of the housing and is capable of detecting four simultaneous finger touch down pressures from the hand.

13. The keyboard of Claim 1 1 , wherein the input means detects actuating pressure by comparing relative sizes of fingertip touchdowns with respect to time.

14. The keyboard of Claim 13, wherein the input means is capable of detecting and tracking a fingertip translational motion.

1 5. The keyboard of Claim 14, wherein the memory means maps a translational motion to one of a command sequence including common command characters.

16. The keyboard of Claim 15 wherein the common command characters are selected from the set: Space, Shift, Tab, Capital Lock, Enter, and Backspace.

17. The keyboard of Claim 16 wherein the set further includes: Function, Control, Delete and Alternative.

18. The keyboard of Claim 1 1, wherein the input means is capable of detecting four fingertip touchdowns in free form.

19. The keyboard of Claim 1 1 , wherein the memory means uses Unified Braille Code for mapping eight finger touch down patterns to alpha/numeric characters.

20. The keyboard of Claim 11 including a computer program providing a graphic representation on the display of the mapping sequence used by the memory means to assist the user in learning a fingertip touch down sequence used to generate the alpha/numeric codes.

21. A method for inputting data into a tablet personal computer, comprising the following steps:

providing a tablet computer having a data display screen on a front side, and a pressure sensitive data input region on an obverse side of the computer;

detecting eight fingertip touch downs on the data input region;

detecting changes in fingertip pressure associated with a data input command; and converting the detected changes to data output commands for display on the data display screen.

22. The Method of Claim 21 wherein during the converting step, detected changes in the fingertip pressure is mapped to characters defined in Unified Braille Code.

23. A rear mounted touchpad data entry system for a computer that adapts to a configuration of a user's grip, comprising:

a plurality of input regions used to detect the user's finger touch and pressure; and, a means of mapping finger pressure sequences to alpha-numeric and control codes.

24. The data entry system in claim 23, wherein means of adapting to a location of the user's grip are provided.

25. The data entry system in claim 23, wherein finger movements of one or more fingers are used to enter or manipulate data.

26. The data entry system in claim 23, wherein tactile feedback is provided to the user upon valid or invalid character or command data entry.

27. The data entry system in claim 23, wherein a graphic representation of the finger mapping codes are used on a front facing display to assist the user in learning the entry sequences.

28. The data entry system in claim 23 , wherein thumbs touching a front facing panel are used in conjunction with the finger pressure sequences to enter or manipulate data.