Presently, significant growth and changes are taking place in the user-interface market. One of the noticeable developments would be the rise of various backlighting available for switch membranes. Membrane switches are widely known for its backlights that range from different levels of brightness, transparency and colors. Thus, it is essential for engineers, product designers and consumers to better comprehend the role of these backlights.
Several membrane switches’ backlighting includes the use of LED’s, optical fiber, and electroluminescent lamps.
LED (Light Emitting Diode) backlights are fascinating to the market as LED’s aid in making a thinner, richer, and more efficient display. Research has it that LED is used to provide “even illumination” over a wide area for a number of imaging or optics applications. Inverters are usually not needed in using this kind of backlight. This backlight is made up of wide and flat illumination particles that lights the object from behind. There are actually two major kinds of LED backlighting; the Edge-lit and local dimming. The former means that the LED’s that brightens up the pixel are located only on the edges of the set. Thus, a light guide points the brightness toward the center of the screen. The local dimming, on the other hand, is dimmed together independently, causing it to better enhance the contrast ratio and power consumption. To sum it up, LED backlights enables thinner backlight designs; has longer lifetime (50,000 hours); and has an adjustable dim light. Just last March 7, 2015, Ozone Gaming launched a new Strike Battle compact mechanical gaming keyboard that comes with a red LED backlight keys; hence, LED backlights keeping up with modern innovations.
Optical fiber (or Fiber Optic) backlighting are panels woven from plastic optical fibers. Its thin, flat panel is void of heat and electromagnetic resistance. Some of the advantages of using this kind of backlighting include: low power requirements; consistent brightness; longer life; and thin profile. In addition, the optical fiber backlights are extraordinarily resistant and virtually maintenance-free. These backlights have undergone series of examinations in over 5 million casualties proving no loss of light and no degeneracy in brightness. It is said that optic fiber panels are as refined as 0.55mm to 0.33mm. A single fiber optic panel can radiate the light from a single LED across a surface measuring 1 by 1in. or 10 by 10in. With this, fiber optic panels are believed to be very efficient in terms of backlighting.
Known by using semiconductor crystals (phosphors), electroluminescent lamps are thin, flexible, and firm. This kind of backlighting produces balanced area lighting and unvarying brightness. By its phosphors, these lamps are able to convert electrical energy to light energy. Electroluminescent lamps are also cheaper than optical fiber; it provides backlighting in a very thin layer between the graphic overlay and the circuit.
From pushbutton keys to mechanical gaming keyboards, backlighting serves as one of the most visually enticing and remarkable aspect of membrane switches.