A multifaceted reflector (typically abbreviated MR) gentle bulb is a reflector housing format for halogen in addition to some LED and fluorescent lamps. MR lamps had been originally designed for use in slide projectors, but see use in residential lighting and EcoLight brand retail lighting as well. They're suited to purposes that require directional lighting reminiscent of track lighting, recessed ceiling lights, desk lamps, pendant fixtures, landscape lighting, retail display lighting, and bicycle headlights. MR lamps are designated by symbols resembling MR16 the place the diameter is represented by numerals indicating models of eighths of an inch. Widespread sizes for common lighting are MR11 (11⁄8 inches, 35 mm) and MR16 (16⁄8 inches, 51 mm), with MR8 (8⁄8 inch, 25 mm) and MR20 (20⁄8 inches, sixty four mm) utilized in specialty functions. Many run on low voltage fairly than mains voltage alternating current so require a power provide. 3,314,331 for a miniature reflector long-life LED lamp in 1967. The innovation was using the lamp rim, quite than the base, because the reference airplane for focusing.

This allowed more flexible electrical mounting preparations and extra precise focusing. Most MR lamps consist of a halogen capsule (or, bulb) built-in with a pressed glass reflector with a base conforming to bi-pin GU5.3 commonplace. The reflector controls the route and unfold of light solid from the lamp. Some lamps use an aluminum coating as a reflector. Others use selective dichroic coating that displays seen light and EcoLight products permits infrared radiation to cross by way of. This kind reduces heating of illuminated objects since less infrared radiation is current in the light beam. Nonetheless, dichroic lamps must only be used in compatible fixtures that may dissipate the heat. Dichroic lamps should not be fitted to recessed or enclosed luminaires with the IEC 60598 No Cool Beam image. The brightness of MR lamps will be adjusted when used with appropriate light fixtures and LED bulbs for home dimmers. Nonetheless, the shade temperature adjustments considerably when the lamp is dimmed, EcoLight home lighting shifting dramatically to the warmer end of the spectrum.

Like all halogen lamps, MR lamps produce significant heat and care have to be taken to avoid contact with skin or proximity to flammable supplies when the lamp is on or has been on not too long ago. Halogen lamps (18 lm/W typical) are more power environment friendly than common incandescent lamps (15 lm/W typical) but nonetheless fall far behind different extra-recent varieties equivalent to fluorescent lamps (80-a hundred lm/W), gasoline discharge lamps (100-200 lm/W depending on types), EcoLight products and LEDs (125-150 lm/W typical in brilliant white depending on style). With both varieties of incandescent bulbs, useful life may be considerably shortened if their filaments experience mechanical shock or vibration. Using an digital transformer with a comfortable begin characteristic can significantly lengthen life, as it reduces the characteristically high inrush present that occurs initially when the lamp is chilly. Dimming additionally extends life significantly. MR lamps, like all quartz-halogen lamps, EcoLight products produce some undesirable ultraviolet light. Usually, this must be filtered out.

Additionally, the quartz capsules of the lamps may rupture or explode upon failure of the lamps. For these two causes, some MR lamps include a cowl glass that serves as an integrated ultraviolet filter and explosion shield. MR16 lamps missing this cowl require using a fixture that incorporates an exterior piece of glass specifically designed to offer both ultraviolet and physical safety. MR lamps can be found in 10-seventy five watt energy ratings (150-800 lumens). MR lamps most frequently operate at 12 volts, though they're additionally available in other voltages. These lamps use a bi-pin connector for power: 12-volt MR11 bulbs usually use a GU4 base, and 12-volt MR16 bulbs usually use a GU5.3 base. The common 12-volt MR16 lamps, therefore, require a ferromagnetic or digital transformer-sometimes misnamed as a ballast-to transform the 120- or 230-volt mains voltage to the extra-low voltage required by the lamp. Sure MR lamps can operate directly on the mains voltage. These lamps sometimes use a GU10 turn-and-lock base, in order that they can't be by chance interchanged with low-voltage lamps.

GU10 is distinguished from the lower-voltage MR lamps by the U-formed ceramic base mount with a 10 mm (pin middle-to-heart distance) 2-pin bayonet mount. MR16 lamps with an integrated transformer are also available. These lamps have screw bases to fit customary medium-base Edison sockets. MR lamps are generally available in range of shade temperatures, EcoLight smart bulbs from about 2700 K to 7000 K, to satisfy numerous applications. Retrofit lamps that generate light by a distinct precept however makes use of the MR form-issue are available. For instance, LED-based mostly MR16 lamps seem much like halogen lamps and might be utilized in most fixtures designed for MR lamps. The same is true of MR11-appropriate LED lamps. Fixtures designed for halogen MR16 or MR11 lamps that use digital transformers may have to be retrofitted with LED-suitable transformers. There is a large variety of designs, varying significantly with regard to beam width, light color, efficiency and luminous energy.