Holland Membrane User Manual

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Overlay- Top layer of a membrane switch (the graphic interface between device and user) generally made 
of polyester or polycarbonate. 
 
Pad Emboss- A raised area on an overlay, which defines an entire graphic. (i.e., a full keypad of L.E.D. 
window.) 
 
Proof- A paper simulation of what a screen printed overlay will look like, submitted to a customer for 
approval. 
 
Polyester Dome- A keypad on a membrane that has been dome-embossed on the overlay or top circuit 
layer to add tactile feedback when the switch is activated. The dome shape, which is usually formed by a 
hydro-forming process, can vary in size and shape to achieve a desired “force” and “tactile feedback” of the 
keypad. 
 
Prototype Tooling- Method of fabricating prototype components without using steel rule dies (hard tooling) 
allowing changes before production runs without expensive tooling charges. 
 
Rail Emboss- A raised area on an overlay which defines the perimeter of a graphic. (i.e., perimeter of a 
keypad or a border.) 
 
Schematic- A drawing showing electrical interconnections and functions of a specific circuit arrangement. 
 
Screen Printing- Method of printing by forcing ink through a mesh selectively.  This is done by closing parts 
of the mesh with a stencil. 
 
Screen Tint- Area of image printed with dots so ink coverage is less than 100%, simulating shading or a 
lighter color. 
 
Selective Texture- A transparent velvet finish printed on specified areas on an overlay to accentuate design 
elements such as windows, keypads or graphics. 
 
Shield- A layer of polyester material that is either laminated with aluminum or printed with conductive ink to 
protect a switch from E.S.D. or E.M.I. interference. 
 
S.M.D.- Surface Mount Device. 
 
S.M.T.- Surface Mount Technology. 
 
Specified Resistance- Maximum allowable resistance measured between two terminations whose internal 
switch contacts, when held closed, complete a circuit. 
 
Sub-Surface Printing- Imaging on the back (second surface) of an overlay so the printed graphic is 
protected from wear by the actual material. 
 
Tactile Ratio- A measure of tactile response. 
 
Tactile Response- A sudden collapse or snapback of a membrane switch prior to contact closure or after 
contact opening. 
 
Tactile Switch- A switch assembly that provides a tactile ratio greater than zero.  Tactile switches give the 
user immediate physical feedback that the switch has been activated.  Tactile feedback on a membrane 
switch can be achieved by using a stainless steel dome or a polydome construction. 
 
Termination- How a switch is connected to the device it activates. 
 
Translucent- Partially transparent.  Having the property of diffusing light. 
 
Transparent- Having the property of transmitting light without appreciable scattering so that objects beneath 
are entirely visible.