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Lighting A quick overview

The Physics The Practical

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What is Light "Light is visually evaluated

radiant energy.“ Electromagnetic Spectrum

http://www.glenbrook.k12.il.us/gbssci/phys/Class/light/u12l2a.html

http://www.arce.ukans.edu/book/contents.htm

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What is the Purpose of Light Allow Performance of Tasks Mood Disguise Emphasize

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Basic Physics Light enters eye, usually reflected

from something Converted to electrical impulse Processed by Brain

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The Lighting Designer’s Task Artistic - Achieve an effect

that creates a “mood” That influences behavior

Functional Put enough light of the right kind on

the “work surface” so a person can work.

Do it economically. This is where the engineer focuses

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Characteristics of Light that matter Energy magnitude - brightness

Relative levels Produces contrast

Absolute Wavelength - Color

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Methods of Light Production Older Ways

Daylight Wood burning Gas burning

Candle Gas from tube

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Terms of the Trade IES

Illuminating Engineering Society of North America

Lamp = Bulb Luminaire = The fixture holding the bulb Efficacy = Number of “lumens per watt” Color Temperature = The temperature

of a solid block producing the same color light.

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Color from Lamps

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Key Issues in Practice How light reflects from surface

Reflection Absorption Diffusion

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Why Do we Use different Lamps?

Cost Initial Cost Efficiency = Operating Cost

Color Rendition Ability to focus light Longevity

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Lamps – Low Efficiency Incandescent

Standard Halogen

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Lamps – Higher Efficiency Low Pressure Discharge

Fluorescent Low Pressure Sodium

High Pressure Discharge Mercury Vapor Metal Halide High Pressure Sodium

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Luminaires Used to direct light

Up Down Sideways Combination

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Material Resources Ching – A Visual Dictionary of

Architecture Mechanical & Electrical Equipment

for Buildings