10/29/2015 www.donsbulbs.com definitions: LIGHT_OUTPUT

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Don's bulbsrare light bulbs and lamps

glossary of terms

definition of: LIGHT OUTPUTWhat is LIGHT OUTPUT?

LIGHT OUTPUT refers to LUMEN.

light output of a bulb is usually expressed either in units of lumens, or, candlepower(CP).

light output of miniature bulbs is often expressed in candlepower, but, larger bulbs areusually expressed in lumens.

One lumen is equal to the amount of light emitted by one candle that falls on onesquare foot of surface located one foot away from one candle.

A uniform source of one candlepower placed in a sphere emits 12.57 lumens or meanspherical candela (MSCP) equals 12.57 lumens; meaning that 1 candle has a totaloutput of light (light output in all directions) equalling 12.57 lumens.

A 100 watt common incandescent bulb emits around 1700 lumens.

Lumen rating of a light bulb is a measurement of ALL the light output from that lightbulb from all directions.

light output diminishes over the life of the bulb.

Initial Lumens is the lumens rating for a brand new light bulb.

Design Lumens is the rated lumens measured at 40 percent of the bulbs rated life.

For general lighting, bulbs usually need to be replaced when their lumens output dropto around 50% of the Initial Lumens.

halogen bulbs are designed to hold their lumens output very well over their life.

references for this page: LUMEN, DESIGN LUMENS, EFFICACY, INITIALLUMENS, INTENSITY, LPW, LIGHT, LIGHT ENERGY, LIGHT OUTPUT, LIGHTOUTPUT INTENSITY, LUMENS, LUMENS OUTPUT PER WATT, POWERFACTOR

references to this page: /BL, /BLB, /BUG-YELLOW, /FS, /GR, /HO, /IR, /OT, /SB,ARC TUBE, BALLAST, BALLAST FACTOR, BEAM ANGLE, BREAKDOWNVOLTAGE, BULB SOCKET, CANDLEPOWER, CATEGORY, CENTER BEAMCANDLEPOWER, COEFFICIENT OF UTILIZATION, COLOR RENDERINGINDEX, COLOR SPECTRUM, COLOR TEMPERATURE, CONVERSION TABLE,

10/29/2015 www.donsbulbs.com definitions: LIGHT_OUTPUT

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