Building Technology: Daylighting, Light Mapping, and Electric Light Sources

Vocabulary practice flashcards covering daylighting strategies, light mapping layers, lighting metrics, and electric light source families (Incandescent, Halogen, Fluorescent, HID, and LED).

Lamp

A light source, commonly referred to as a light bulb.

Luminaire

The complete lighting fixture, consisting of the light source together with the components that support, power, protect, or control its light.

Incandescent Lamp

A source that generates light when an electric current heats a filament until it glows, contained within a glass envelope holding a fill gas or vacuum.

Halogen Lamp

A form of incandescent lamp utilizing a halogen gas cycle to preserve the filament, operate at higher temperatures, and produce whiter light with improved efficacy.

Fluorescent Lamp

A discharge lamp in which an electrical discharge excites mercury atoms in an inert gas to produce ultraviolet radiation, which an interior phosphor coating converts into visible light.

Ballast

An auxiliary electrical component required by discharge lamps (such as fluorescent and HID) to provide starting conditions and regulate operating current.

High-Intensity Discharge (HID) Lamp

A high-output light source family that produces illumination through an electrical arc between electrodes passing through gas and metal vapours inside an inner arc tube.

Metal Halide

A type of HID lamp used for high-output illumination whose colour performance depends on lamp type and is prone to shifting across its lifespan.

High-Pressure Sodium

A type of HID lamp typically characterized by yellow-orange light output and limited colour discrimination in standard applications.

Mercury Vapour

An older HID light source family commonly encountered in legacy or existing installations.

Light-Emitting Diode (LED)

A solid-state light source that emits energy in the form of photons when an electric current passes through a semiconductor material.

LED Driver

An internal or external electronic device that converts and regulates electrical power supplied to LED chips and modules.

UV-C Disinfection Lamp

A discharge lamp designed without a phosphor coating that transmits germicidal UV-C radiation through its envelope to inactivate microorganisms in air, water, or on surfaces.

Lumens (lm)

The measurement unit of total luminous flux indicating the quantity of light emitted by a source; higher values correspond to greater brightness.

Efficacy (lm/W)

The metric representing lighting efficiency, calculated as total light output divided by electrical power consumed ($\text{lm}/\text{W}$).

Correlated Colour Temperature (CCT)

A specification measured in Kelvins ($\text{K}$) defining the visual warmth or coolness of white light, where higher numbers indicate cooler appearances.

Colour Rendering Index (CRI)

A metric scaled from 0 to 100 that indicates how accurately illuminated colours appear relative to an ideal reference source, with scores under 80 considered poor and 90+ excellent.

L Rating

An LED metric defining the expected remaining light output percentage after a designated lifespan; for instance, L70 signifies 70% light output retained.

Tunable White LEDs

LED products engineered to allow the correlated colour temperature of white light to be adjusted within a specific Kelvins range.

Dim-to-Warm

A control capability where an LED source becomes progressively warmer in colour appearance as it dims, replicating the behaviour of incandescent lamps.

Simple Payback

An economic assessment metric defined by the formula: $\text{Simple payback} = \frac{\text{installed upgrade cost}}{\text{annual cost savings}}$.

Direct Sunlight

A daylight component consisting of unobstructed sun rays producing sharp light patches and distinct shadows that often requires shading to mitigate glare and heat gain.

Sky Light

Atmospherically diffused natural light whose illumination intensity and colour temperature shift continuously with time of day and meteorological conditions.

Reflected Daylight

Natural light that reaches an interior space after bouncing off surrounding outdoor terrain, adjacent buildings, or interior room finishes.

Overhang Soffit

A horizontal architectural projection that provides side-lighting control by shading windows from overhead sun angles.

Light Shelf

A horizontal shading and redirecting device that shields the lower viewing area of a window while reflecting daylight upward toward the ceiling to reach deeper into the room.

Light Monitors

Raised structural side-lighting devices that can shade the lower part of a window while bouncing daylight toward the ceiling plane.

Clearstories

High fenestration openings positioned along upper wall boundaries to cast daylight deep into spaces and illuminate ceilings while preserving lower wall real estate.

Vertical Shading

Exterior architectural fins or louvers used to manage side-lighting by intercepting oblique, low-angle sunlight from the east or west.

Bounced Skylights

Top-lighting roof fenestrations that direct incoming daylight onto an integrated reflective surface prior to entering the occupied interior to diffuse and soften light distribution.

Shielded Skylights

Top-lighting apertures equipped with interior or exterior baffles to obstruct direct sightlines to the sky and intercept piercing solar exposure.

Fixture Plan

A technical lighting layout drawing that defines the specific placement, physical properties, and models of lighting hardware in a building.

Light Map

A conceptual design graphic that diagrams the intended lighting effects, target surfaces, luminance hierarchies, and functional focal points prior to fixture selection.

Choreography Layer

The layer of light mapping that structures the visual journey and circulation across spaces by highlighting destinations and establishing cones of view.

Accent Lighting Layer

The light mapping layer dedicated to establishing visual hierarchy by highlighting focal objects, artwork, or merchandise through brightness contrast.

Wall Washing

An architectural illumination technique providing a smooth, uniform wash of light across an entire vertical surface.

Grazing

An architectural illumination technique directing light across a wall surface at a very narrow, acute angle to accentuate irregularities and textural depth.

Task Lighting Layer

The lighting layer that targets dedicated functional work planes to provide adequate illumination for specific activities without casting shadows or screen reflections.