Holland Membrane manual Glossary Appendix D

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Glossary

Appendix D

Actuation Force- The maximum force measured prior to or including the point at which keypad contact closure is achieved.

Alodine- A chemical conversion process that oxidizes aluminum to form a non-porous aluminum oxide. Referred to as “poor-man’s anodizing” because it is less costly and not as durable as anodizing.

Anodize- Electro-chemical oxidation of aluminum to form aluminum oxide with a porous nature. The anodized layer can be durably colored and is non-conductive, non-corrosive and resistant to abrasion.

Arcing- Discharge of electricity (a spark) that can occur when contacts are opened or closed. Arcing can degrade or burn contacts, reducing useful life.

Backlighting- A flexible layer within a membrane switch construction that illuminates select areas of the overlay, such as text or graphic symbols. Examples of backlighting methods are E.L. (electroluminescent) or fiber optic.

Circuit- Functioning component (sub-layer) of a membrane switch. Typically made of a silver conductive ink printed on polyester. Also can be a flexible copper circuit, a PCB or polyester printed with other conductive materials.

Contact Bounce- (Make) – Point at which specified resistance is achieved.

Dead Front- Printing translucent ink in an area so that the graphic is visible only when backlit.

Density- The degree to which light transmits through a color or transparent window. The higher the density, the less light will be transmitted.

Dielectric Strength- The voltage that an insulating material can withstand before breakdown occurs, usually expressed as a voltage gradient (such as volts per mil.)

E.M.I. (also R.F.I)- Electromagnetic Interference (Radio Frequency Interference.) Radiated energy from electrical devices, lightning and similar sources which interferes with the proper operation of electronic circuitry.

E.S.D.- Electrostatic Discharge – transfer of high potential electrical charge between objects by contact or through air.

Files- Information or documentation created electronically by computer.

Font- A set of characters having a unified design.

Gloss Level- The degree of shininess of a particular material, usually specified in percentages such as 75% gloss, 90% gloss, and so forth.

Halftone- Image made of a pattern of various size and shape dots (newspaper photograph) rather than continuous gray.

Image-Setting-The process by which electronic files are transferred to film or paper directly from the computer (computer onto film technology.)

L.E.D.- Light Emitting Diode.

Membrane Switch- A momentary switching device in which at least one contact is made of a flexible substrate.

Moisture Resistance- Ability of a material to repel moisture either from air or when subjected to water. Non-Tactile Switch- A switch assembly that has a tactile ratio equal to zero.

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Contents Membrane Switch Design Guide Overlay Materials IntroductionArtwork Color Matching Cosmetic Inspection Ultraviolet HardcoatsEmbossing Mechanical TolerancesPinouts Laser CuttingESD/RFI Shielding Interconnect Tail Exit PointScreen Printed Flex Circuits Creasing of Flex Circuits Rigid Membrane SwitchesDomes Electrical Performance Operating Temperature RangeActuation Force Loop ResistanceWindows Life Cycle TestingInsertable Legends Embedded LEDs Thick Film ResistorsMounting Adhesives Subpanels Drawings and SpecificationsBacklighting Holland Nameplate Overlay Material Guide Appendix a EBATail termination Type of switchTail details PinoutLogos and special graphics ShieldingOverlay Material Windows/Lens coatingInsertable legends EmbossingHydroforming Support panelSwitch Venting Requirements Switch Sealing RequirementsColor matching Membrane Sample Appendix C Page Page Page Page Glossary Appendix D