Split keyboard for a tablet computer

Abstract

A dual keyboard system is presented for use with a tablet computer. Each keyboard is attached to a suction cup via a hinge. The suction cups attach to the display face of the tablet computer. The keyboards can be rotated about the hinge to allow viewing of the full display of the tablet computer without detaching the keyboards. In one embodiment, the hinge is separable, allowing removal of the keyboards completely while leaving the suction cups attached to the tablet computer. In another embodiment, a master keyboard receives keystrokes directly from a slave keyboard as well as from keys located on the master keyboard. The tablet computer communicates only with the master keyboard via a radio frequency link. The slave keyboard communicates with the master keyboard via a radio frequency or infrared link.

What is claimed is: 
     
         1 . A keyboard system comprising:
 a) a first keyboard having:
 i) a first set of keys, 
 ii) a first wireless transmitter, and 
 iii) a first keyboard processor that receives keystrokes from the first set of keys and converts the keystrokes into a keyboard keystroke signal that is transmitted over the wireless transmitter; and 
   b) a second keyboard having:
 i) a second set of keys, 
 ii) a wireless receiver that receives the keyboard keystroke signal from the first wireless transmitter of the first keyboard, 
 iii) a second wireless transmitter, and 
 iv) a keyboard processors that
 (1) receives keystrokes from the second set of keys and converts the keystrokes into a first tablet keystroke signal that is transmitted over the second wireless transmitter, and 
 (2) receives the keyboard keystroke signal from the wireless receiver and converts the keyboard keystroke signal into a second tablet keystroke signal that is transmitted over the second wireless transmitter. 
 
   
     
     
         2 . The keyboard system of  claim 1 , wherein the first wireless transmitter transmits an infrared signal and the wireless receiver receives the infrared signal. 
     
     
         3 . The keyboard system of  claim 2 , wherein the second wireless transmitter transmits a radio frequency signal to a tablet computer. 
     
     
         4 . The keyboard system of  claim 1 , wherein the first wireless transmitter transmits a first radio frequency signal and the wireless receiver receives the first radio frequency signal. 
     
     
         5 . The keyboard system of  claim 4 , wherein the second wireless transmitter transmits a second radio frequency signal to a tablet computer, and further wherein the first and second radio frequency signals are both formatted according to a Bluetooth standard created by the Bluetooth Special Interest Group, and further wherein the first radio frequency signal is non-discoverable at the same time the second radio frequency signal is discoverable by the tablet computer. 
     
     
         6 . A keyboard for a tablet computer comprising:
 a) a keyboard body having a top side and a bottom side;   b) a set of keys located on the top side of the keyboard body; and   c) a suction cup having a closed end and an open end, with the closed attached to the bottom side of the keyboard body.   
     
     
         7 . The keyboard of  claim 6 , further comprising:
 d) a radio frequency transmitter for transmitting keystrokes, based on pressed keys in the first set of keys, as radio frequency signals   
     
     
         8 . The keyboard of  claim 7 , further comprising:
 e) a tablet computer having:
 i) a radio frequency receiver for receiving the transmitted keystrokes, and 
 ii) a flat display screen; 
   
       wherein the open end of the suction cup is attached to the flat display screen of the tablet computer. 
     
     
         9 . The keyboard of  claim 7 , further comprising:
 f) a hinge having
 i) a first portion attached to the bottom side of the keyboard body, 
 ii) a second portion attached to the closed end of the suction cup, and 
 iii) a pivot portion that allows the first and second portions to rotate with respect to one another. 
   
     
     
         10 . The keyboard of  claim 9 , wherein the second portion comprises a support portion upon which the bottom side of the keyboard rests when the keyboard is in a use position. 
     
     
         11 . The keyboard of  claim 10 , further comprising:
 g) a foot located on the bottom side of the keyboard body, the foot contacting the flat display screen of the tablet computer when the keyboard rests on the support portion in a use position and the open end of the suction cup is attached to the flat display screen.   
     
     
         12 . The keyboard of  claim 11 , further comprising:
 h) a second keyboard body having:
 i) a top side and a bottom side, 
 ii) a second set of keys located on the top side of the second keyboard body, the second set of keys including a plurality of keys not found in the first set of keys, 
 iii) a second foot located on the bottom side of the second keyboard body, 
 iv) a second hinge attached to the bottom side of the second keyboard body, the second hinge having a second pivot point, and 
 v) a second suction cup having a closed end attached to the second hinge opposite the second pivot point of the keyboard body, the second suction cup also have an open end attached to the flat display screen of the tablet computer. 
   
     
     
         13 . The keyboard of  claim 12 , wherein the second keyboard body further comprises:
 vi) a second wireless transmitter that transmits keyboard keystroke signals;   wherein the keyboard further comprises a wireless receiver on the first keyboard body that receives keyboard keystroke signals from the second wireless transmitter; and   further wherein the radio frequency transmitter transmits keystrokes based on received keyboard keystroke signals to the tablet computer.   
     
     
         14 . The keyboard of  claim 13 , wherein the second wireless transmitter transmits an infrared signal. 
     
     
         15 . The keyboard of  claim 10 , wherein the hinge is a separable hinge. 
     
     
         16 . The keyboard of  claim 15 , wherein the pivot portion of the hinge is formed by a pair of arms on the first portion of the hinge resting in a pair of slots found on the second portion of the hinge, wherein the first and second portions of the hinge can be separated by removing the pair of arms from the pair of slots. 
     
     
         17 . A method for using a pair of keyboards with a tablet computer comprising:
 a) attaching a first keyboard to a display of the tablet computer;   b) attaching a second keyboard to the display of the tablet computer;   c) receiving a first key press of a first key located on the first keyboard;   d) transmitting a first signal indicative of the first key press over a first wireless link from the first keyboard to the second keyboard;   e) transmitting a second signal indicative of the first key press over a second wireless link from the second keyboard to the tablet computer;   f) receiving a second key press of a second key located on the second keyboard; and   g) transmitting a third signal indicative of the second key press over the second wireless link from the second keyboard to the tablet computer.   
     
     
         18 . The method of  claim 17 , further comprising delaying the transmission of the third signal to compensate for the delay between receiving the first key press of the first key and the transmission of the second signal. 
     
     
         19 . The method of  claim 17 , wherein the step of attaching the first keyboard to the display of the tablet computer further comprises:
 i) attaching the first keyboard to a suction cup via a hinge,   ii) attaching the suction cup to the display of the tablet computer, and   iii) swiveling the first keyboard about the hinge from a vertical position to a horizontal position that is approximately parallel with the display of the tablet computer.   
     
     
         20 . A method for using a pair of keyboards with a tablet computer comprising:
 a) providing a first keyboard having a first subset of keys;   b) providing a second keyboard having a second subset of keys, the second subset of keys having a plurality of keys not found in the first subset of keys;   c) establishing a first Bluetooth connection directly between the first keyboard and a tablet computer;   d) establishing a second Bluetooth connection directly between the second keyboard and the tablet computer;   e) submitting a first keystroke signal from the first keyboard to the tablet computer over the first Bluetooth connection without the first keystroke signal passing through the second keyboard; and   f) submitting a second keystroke signal from the second keyboard to the tablet computer over the second Bluetooth connection without the second keystroke signal passing through the first keyboard.