Patent ID: 8726183

Claim:
An input apparatus configured to sequentially change a set value, comprising: an operating key configured to be pressed; a detector configured to detect press of the operation key; a calculation portion configured to sequentially add or subtract a first variable to or from the set value during the press of the operation key and sequentially add or subtract a second variable greater than the first variable to or from the set value after a number of calculations with the first variable exceeds a first threshold number; a determination portion configured to determine whether the number of the calculations with the first variable exceeds a second threshold number smaller than the first threshold number, the determination portion including a memory element configured to store the second threshold number in advance; and a change portion configured to change the operating key in colour from a first hue to a second hue in response to a trigger signal that is output from the determination portion when the number of the calculations with the first variable exceeds the second threshold number.