US 12,340,030 B2
Keyboard apparatus in which touch pad is located based on Fitts's law
Kiichiro Shimosaka, Kahoku (JP); Yoshie Fuchigami, Kahoku (JP); and Satoshi Kubota, Kahoku (JP)
Assigned to PFU LIMITED, Kahoku (JP)
Filed by PFU LIMITED, Kahoku (JP)
Filed on Apr. 26, 2024, as Appl. No. 18/647,997.
Claims priority of application No. 2023-097935 (JP), filed on Jun. 14, 2023.
Prior Publication US 2024/0419258 A1, Dec. 19, 2024
Int. Cl. G06F 3/02 (2006.01); G06F 3/0354 (2013.01)
CPC G06F 3/0213 (2013.01) [G06F 3/03547 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A keyboard apparatus comprising:
an enclosure;
a plurality of keys located on a top face of the enclosure; and
a touch pad provided on at least one side face of the enclosure, wherein
a shortest distance D between a key assigned to a home position out of the plurality of keys and an upper end of a side face on which the touch pad is provided, and a width W of the touch pad satisfy a compound inequality of:

OG Complex Work Unit Math
wherein the compound inequality log2 (1+D/W) is a logarithmic term referred to as an index of difficulty (ID) and the numbers 2.2 and 4.1 are the lower and upper limits used to suitably locate the plurality of keys between the home position and the touch pad.