When a rubber keypad or rubber membrane switch calls for backlighting, you may often hear the term “laser etching” being used. Laser etching refers to a process in which a high powered laser is utilized to remove a layer or layers of paint on a keypad.
A standard rubber keypad is simply printed to add graphics or nomenclature. This method will suffice as long as the keypad is not backlit. It’s a cheap and easy way to create letters, numbers, and special characters on keys, making it the preferred choice among many companies. But in order to backlight molded rubber, the rubber must be laser etched: which is a newer, more advanced method for producing backlit nomenclature, graphics, indicators, etc.
The molded rubber typically starts off as a translucent, milky-like color and is then painted with opaque colors designed into the part. The rubber is then laser etched down to the translucent layer(s) of the keypad that will eventually be backlit with LEDs. The laser is carefully guided across the surface of the key, burning away paint in select areas. After the paint has been removed, it reveals the translucent layer below. The result is a contrasting translucent and opaque color, making the backlit areas pop with a higher level of crispness, brightness and visibility.
Laser etched keypads are extremely rugged and durable. The combination of molded light blocks inside the part and the laser etched nomenclature on the faceplate make for an unmatched backlit keypad.