A multifaceted reflector (often abbreviated MR) light bulb is a reflector housing format for EcoLight halogen in addition to some LED and fluorescent lamps. MR lamps had been originally designed for use in slide projectors, EcoLight bulbs but see use in residential lighting and retail lighting as nicely. They're suited to functions that require directional lighting resembling observe lighting, recessed ceiling lights, desk lamps, pendant fixtures, landscape lighting, retail display lighting, and bicycle headlights. MR lamps are designated by symbols corresponding to MR16 the place the diameter is represented by numerals indicating units of eighths of an inch. Frequent sizes for general lighting are MR11 (11⁄8 inches, 35 mm) and MR16 (16⁄8 inches, fifty one mm), with MR8 (8⁄8 inch, 25 mm) and MR20 (20⁄8 inches, sixty four mm) used in specialty applications. Many run on low voltage rather than mains voltage alternating current so require a power supply. 3,314,331 for a miniature reflector lamp in 1967. The innovation was utilizing the lamp rim, slightly than the bottom, EcoLight solar bulbs because the reference plane for focusing.

This allowed extra flexible electrical mounting preparations and more exact focusing. Most MR lamps include a halogen capsule (or, bulb) integrated with a pressed glass reflector with a base conforming to bi-pin GU5.3 standard. The reflector controls the direction and unfold of light forged from the lamp. Some lamps use an aluminum coating as a reflector. Others use selective dichroic coating that displays visible gentle and permits infrared radiation to pass through. This sort reduces heating of illuminated objects since less infrared radiation is present in the sunshine beam. Nonetheless, dichroic lamps should solely be utilized in suitable fixtures that can dissipate the heat. Dichroic lamps must not be fitted to recessed or enclosed luminaires with the IEC 60598 No Cool Beam symbol. The brightness of MR lamps can be adjusted when used with applicable gentle fixtures and dimmers. However, the colour temperature changes considerably when the lamp is dimmed, shifting dramatically to the hotter finish of the spectrum.

Like all halogen lamps, MR lamps produce significant heat and care should be taken to avoid contact with skin or proximity to flammable materials when the lamp is on or has been on just lately. Halogen lamps (18 lm/W typical) are extra power efficient than regular incandescent lamps (15 lm/W typical) however still fall far behind different more-recent sorts such as fluorescent lamps (80-100 lm/W), fuel discharge lamps (100-200 lm/W relying on varieties), and EcoLight bulbs LEDs (125-one hundred fifty lm/W typical in vibrant white depending on style). With each kinds of incandescent EcoLight bulbs, helpful life might be significantly shortened if their filaments experience mechanical shock or vibration. Utilizing an electronic transformer with a soft start feature can significantly prolong life, because it reduces the characteristically excessive inrush current that occurs initially when the lamp is chilly. Dimming also extends life significantly. MR lamps, like all quartz-halogen lamps, EcoLight bulbs produce some undesirable ultraviolet light. Usually, this must be filtered out.

Additionally, the quartz capsules of the lamps could rupture or explode upon failure of the lamps. For these two causes, some MR lamps include a cover glass that serves as an built-in ultraviolet filter and explosion shield. MR16 lamps lacking this cowl require using a fixture that incorporates an external piece of glass particularly designed to provide both ultraviolet and physical safety. MR lamps can be found in 10-75 watt power rankings (150-800 lumens). MR lamps most frequently function at 12 volts, though they're additionally out there in other voltages. These lamps use a bi-pin connector for power: 12-volt MR11 bulbs often use a GU4 base, and 12-volt MR16 bulbs usually use a GU5.Three base. The frequent 12-volt MR16 lamps, therefore, require a ferromagnetic or electronic transformer-sometimes misnamed as a ballast-to convert the 120- or 230-volt mains voltage to the extra-low voltage required by the lamp. Certain MR lamps can function directly on the mains voltage. These lamps typically use a GU10 turn-and-lock base, so they can't be accidentally 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 center-to-heart distance) 2-pin bayonet mount. MR16 lamps with an built-in transformer are also obtainable. These lamps have screw bases to fit normal medium-base Edison sockets. MR lamps are commonly out there in range of colour temperatures, from about 2700 Ok to 7000 Ok, to fulfill varied functions. Retrofit lamps that generate gentle by a distinct precept but uses the MR kind-factor can be found. For example, LED-primarily based MR16 lamps seem much like halogen lamps and EcoLight bulbs may 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 need to be retrofitted with LED-appropriate transformers. There is a wide variety of designs, varying considerably with regard to beam width, mild colour, efficiency and luminous energy.