Hardware button is the control that triggers some activity or toggles state of the system.
Types of buttons
Buttons are probably the most popular type of controls, so there is an endless amount of button variants. Here is a set of main types, grouped by behavior or implementation:
By behavior
- Normal button
- Pressable button
- Button with indicator
By implementation
- Mechanical button
- Membrane button
- Sensor button
Design and behavior considerations
Blind usage
Physical size
Comfortable minimum size of the button is 16 mm. The minimum size is 8 mm for smallest dimension.
Bouncing
Ergonomics of button travel distance
Different buttons have different travel distance, or “depth of pressing”. If it is relatively small, then the button is considered as flat, and typically is marketed as “better”, but actually the smaller the distance, the easier it is to click the button accidentally. To avoid this, the press resistance can be increased, but it may have other negative side effects. So, we can select the button, that is relatively “soft” for the user, but has bigger travel distance to avoid accidental clicks.
Inertia
Sophisticated buttons may implement additional state for intermediate state. For instance, if the user clicks the “Start” of diesel heater, it takes some time to turn it on, and the button may blink with separate “intermediate” color.