Keyboard for under water use

A keyboard for use under water, comprising:

• a casing composed of a lower half with a bottom and an upper half including a lid with an opening;
• a key plate having an upper face and a lower face provided on said bottom of said lower half and having a plurality of actuator keys formed on said upper face thereof and protruding from said opening of said lid;
• means for normally retaining said plurality of actuator keys in an unpressed position;
• a switch contact assembly provided on said lower face of said key plate, said switch contact assembly including a first membrane layer having a first conductive pattern, a second membrane layer having a second conductive pattern and a partition membrane disposed between said first and second membrane layers for separating said first conductive pattern from said second conductive pattern in a normally open switch, said partition membrane having a hole means which permits a portion of said first conductive pattern to engage with a portion of said second pattern when said first membrane layer is pressed by one of said actuator keys so as to generate a signal corresponding to said actuator key, the periphery of said first membrane layer being adhesively connected to a face of said partition membrane and the periphery of said second membrane layer being adhesively connected to another face of said partition membrane, said key plate further including a water tight compartment formed on said lower face thereof and having a circuit board therein;
• said water tight compartment further including an opening;
• a cable means having one end connected to said conductive patterns of said adhesively bonded membrane layers and another end of which extends through said opening to connect with said-circuit board;
• and
• a sealing member provided around said opening of said water tight compartment to prevent water from seeping therein.