Lux - Revision history

Designing Buildings at 07:10, 21 January 2021

2021-01-21T07:10:18Z

← Older revision		Revision as of 07:10, 21 January 2021
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	* Visible light.		* Visible light.

−	[[Category:Theory]] [[Category:Design]]	+	[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:DCN_Standard]] [[Category:Definitions]] [[Category:Theory]] [[Category:Design]]

Editor: Reverted edits by 194.83.66.253 (talk) to last revision by Designing Buildings

2019-10-16T13:35:03Z

Reverted edits by 194.83.66.253 (talk) to last revision by Designing Buildings

← Older revision		Revision as of 13:35, 16 October 2019
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	* Luminous flux.		* Luminous flux.
	* Natural light.		* Natural light.
−	* Power factor.h	+	* Power factor.
	* Types of lamp.		* Types of lamp.
	* Types of lighting.		* Types of lighting.
	* Visible light.		* Visible light.

−	~~[[Category:Conservation]]~~ [[Category:Theory]] [[Category:Design]]	+	[[Category:Theory]] [[Category:Design]]

194.83.66.253 at 10:54, 16 October 2019

2019-10-16T10:54:35Z

← Older revision		Revision as of 10:54, 16 October 2019
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	* Luminous flux.		* Luminous flux.
	* Natural light.		* Natural light.
−	* Power factor.	+	* Power factor.h
	* Types of lamp.		* Types of lamp.
	* Types of lighting.		* Types of lighting.
	* Visible light.		* Visible light.

−	[[Category:Theory]] [[Category:Design]]	+	[[Category:Conservation]] [[Category:Theory]] [[Category:Design]]

Designing Buildings at 07:15, 24 May 2019

2019-05-24T07:15:53Z

← Older revision		Revision as of 07:15, 24 May 2019
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	* A 140W sodium street lamp 13,000 lm		* A 140W sodium street lamp 13,000 lm

−	The illumination of a surface S that is 1m x 1m will be 1 lux (or 1 metre-candle) when a lamp of 1 candela (see below for definition) is placed one metre away from it. In other words, 1 lux of light intensity is spread over the 1m2 surface of S which will be equal to 1 lm/m2)~~. By increasing the distance to 2m reduces the luminance to 0.5 lm/m2~~.	+	The illumination of a surface S that is 1m x 1m will be 1 lux (or 1 metre-candle) when a lamp of 1 candela (see below for definition) is placed one metre away from it. In other words, 1 lux of light intensity is spread over the 1m2 surface of S which will be equal to 1 lm/m2).

−	A light source producing 1,000 lm that is 1m away from a surface of area 1m2 produces an illuminance on the surface of 1,000 lux. When the same light source is applied to an area of 10m2, the illuminance level is one tenth of the original, or 100 lm. ~~This shows that lighting~~ larger areas requires greater intensity light sources…or more bulbs.	+	A light source producing 1,000 lm that is 1m away from a surface of area 1m2 produces an illuminance on the surface of 1,000 lux. When the same light source is applied to an area of 10m2, the illuminance level is one tenth of the original, or 100 lm. Lighting larger areas requires greater intensity light sources…or more bulbs.

	A 100W incandescent light bulb produces 1,700 lumens and is regarded as sufficient for general domestic and task lighting applications.		A 100W incandescent light bulb produces 1,700 lumens and is regarded as sufficient for general domestic and task lighting applications.

Designing Buildings at 07:13, 24 May 2019

2019-05-24T07:13:26Z

← Older revision		Revision as of 07:13, 24 May 2019
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−	In physics, a lux (symbol lx) is a standard unit ~~that is~~ used to measure light intensity (or illuminance, or illumination). It is the intensity with which a surface is illuminated and is part of the SI system of measurement~~. The lux is used as a measure of light intensity, whether of light hitting a surface or passing through a surface~~.	+	In physics, lux (symbol lx) is a standard unit used as a measure light intensity (illuminance, or illumination). It is the intensity with which a surface is illuminated and is part of the SI system of measurement.

−	One lux is equal to one lumen per square metre (1 lm/m2). ~~A lumen can be thought~~ of ~~as representing~~ the quantity of light ~~and is a standard unit that indicates the total amount of light produced~~ by a ~~light source, e.g~~ a ~~lamp, candle, LED etc~~. ~~Examples are~~:	+	One lux is equal to one lumen per square metre (1 lm/m2) where a lumen (lm) is the ‘...SI unit of luminous flux, describing the quantity of light emitted by a lamp or received at a surface.’
		+
		+	Typically:

	* A bicycle lamp may produce 10 lm		* A bicycle lamp may produce 10 lm
−	* 100W incandescent light bulb 1,700 lm	+	* A 100W incandescent light bulb 1,700 lm
−	* 150W tungsten spot lamp 2,000 lm	+	* A 150W tungsten spot lamp 2,000 lm
−	* 140W sodium street lamp 13,000 lm	+	* A 140W sodium street lamp 13,000 lm

	The illumination of a surface S that is 1m x 1m will be 1 lux (or 1 metre-candle) when a lamp of 1 candela (see below for definition) is placed one metre away from it. In other words, 1 lux of light intensity is spread over the 1m2 surface of S which will be equal to 1 lm/m2). By increasing the distance to 2m reduces the luminance to 0.5 lm/m2.		The illumination of a surface S that is 1m x 1m will be 1 lux (or 1 metre-candle) when a lamp of 1 candela (see below for definition) is placed one metre away from it. In other words, 1 lux of light intensity is spread over the 1m2 surface of S which will be equal to 1 lm/m2). By increasing the distance to 2m reduces the luminance to 0.5 lm/m2.

Editor: Created page with "In physics, a lux (symbol lx) is a standard unit that is used to measure light intensity (or illuminance, or illumination). It is the intensity with which a surface is illuminate..."

2019-05-02T19:12:15Z

Created page with "In physics, a lux (symbol lx) is a standard unit that is used to measure light intensity (or illuminance, or illumination). It is the intensity with which a surface is illuminate..."

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In physics, a lux (symbol lx) is a standard unit that is used to measure light intensity (or illuminance, or illumination). It is the intensity with which a surface is illuminated and is part of the SI system of measurement. The lux is used as a measure of light intensity, whether of light hitting a surface or passing through a surface.

One lux is equal to one lumen per square metre (1 lm/m2). A lumen can be thought of as representing the quantity of light and is a standard unit that indicates the total amount of light produced by a light source, e.g a lamp, candle, LED etc. Examples are:

* A bicycle lamp may produce 10 lm
* 100W incandescent light bulb 1,700 lm
* 150W tungsten spot lamp 2,000 lm
* 140W sodium street lamp 13,000 lm

The illumination of a surface S that is 1m x 1m will be 1 lux (or 1 metre-candle) when a lamp of 1 candela (see below for definition) is placed one metre away from it. In other words, 1 lux of light intensity is spread over the 1m2 surface of S which will be equal to 1 lm/m2). By increasing the distance to 2m reduces the luminance to 0.5 lm/m2.

A light source producing 1,000 lm that is 1m away from a surface of area 1m2 produces an illuminance on the surface of 1,000 lux. When the same light source is applied to an area of 10m2, the illuminance level is one tenth of the original, or 100 lm. This shows that lighting larger areas requires greater intensity light sources…or more bulbs.

A 100W incandescent light bulb produces 1,700 lumens and is regarded as sufficient for general domestic and task lighting applications.

The candela (cd) is a unit of source intensity used in the specification of lighting and can be thought of as being equal to one large domestic candle. Examples are:

* A torch bulb (not LED) = 1 candela (emits one lumen of light flux)
* A 60W tungsten bulb = 50 candela
* A single fluorescent tube = 400 candela

= Related articles on Designing Buildings Wiki =

* Adequate lighting.
* Architectural LED market.
* BREEAM Internal and external lighting.
* BREEAM Visual comfort Daylighting.
* BREEAM Visual comfort Glare control.
* Daylight factor.
* Daylight lighting systems.
* General lighting v task lighting.
* Glare.
* Illuminance.
* Lamp efficacy.
* Light fitting.
* Lighting and energy efficiency.
* Luminaire efficacy.
* Luminous flux.
* Natural light.
* Power factor.
* Types of lamp.
* Types of lighting.
* Visible light.

[[Category:Theory]] [[Category:Design]]