Editing Omron B3K series (section)

==Description==
B3K switches facilitate LED [[Backlit keyboard|backlighting]] via a light pipe leading to a surface-mounted LED. The design is said to focus the light more evenly through the legends on the [[keycap]] and minimise light leakage<ref name="romerg3" />. The patents describe various approaches to achieving the illumination, illustrated with light intensity plots.

The slider has four corner posts. Two of these each holds a sliding ramp, each holding one pair of metal contacts apart.
The slider is supported by a large spring, which sits around the centre light guide.
The switch provides redundant sensing in an SPST arrangement by using a pair of identical terminals, each bearing a stationary contact and a movable contact.
The two lateral ends of each terminals are at 90° to each other, and collectively the terminals occupy all four sides within the switch, with the movable contact at one end of each terminal meeting the stationary contact at the opposite end of the other terminal.

Similar to [[Cherry MX]], tactile variants have a bump on the sliding ramps.
The patent depicts the tactile "pressing rib" design but does not explain the shape or mention tactility.
The tactile variants have been compared in feel to the [[Cherry MX Brown]] switch by those who have tried it.<ref name="DT-review" /><ref name="GH-review" />