History of Lighting
DEFINING LIGHT
Prepared by:
Arch Lea Jamora Javier
INTRODUCTION TO LIGHT
Light is a prerequisite for all visual perception. The eye needs light in
order to see things. Light gives objects form, creates relations between
areas and shapes and makes them perceivable.
Light transform our atmosphere.
DEFINING LIGHT
• WHAT IS LIGHT?
• A NATURAL AGENT THAT STIMULATES OUR SENSE OF SIGHT AND
MAKE THINGS VISIBLE.
• A NATURAL PHENOMENA THAT MAKES US SEE
• A WAVELENGTH WHERE OUR VISIBLE EYES CAN SEE COLORS
DEFINING LIGHT
Light is a form of electromagnetic wave and
constitutes a small part of the electromagnetic
spectrum that is visible to the human eye.
Hence, it is called visible light. Since visible
light is a form of a wave, it is defined by its
characteristic wavelength and frequency. The
visible light spectrum is located within a
wavelength range of 380 to 740 nanometers
(nm) or a frequency range of 405 to 790
terahertz (THz).
DEFINING LIGHT
WAVELENGTH OF VISIBLE LIGHT
BETWEEN 380 – 750 NM
DEFINING LIGHT
DEFINING LIGHT
WAVELENGTH OF VISIBLE LIGHT
WHY DO SEE COLORS?
DEFINING LIGHT
WAVELENGTH OF VISIBLE LIGHT
DEFINING LIGHT
THE HUMAN EYE AND THE POWERFUL BRAIN
DEFINING LIGHT
THE HUMAN EYE AND THE POWERFUL BRAIN
DEFINING LIGHT
THE HUMAN EYE AND OUR POWERFUL BRAIN
DEFINING LIGHT
THE HUMAN EYE ADAPTION STATE
AGE
HEALTH
CONDITION
DEFINING LIGHT
THE HUMAN EYE ADAPTION STATE
DAWN NOON DUSK
DEFINING LIGHT
THE HUMAN EYE ADAPTION STATE
WHAT HAPPENS TO YOUR EYES FROM A VERY
BRIGHT ENVIRONMENT TO DARK ENVIRONEMENT?
FROM DARK TO BRIGHT ?
GIVE EXAMPLE
DEFINING LIGHT
THE HUMAN EYE ADAPTION STATE
DEFINING LIGHT
TWO KINDS OF LIGHT SOURCES
•The NATURAL LIGHT SOURCE
In the ancient times , man was so happy with candles , lamps and the moon
at night.
DEFINING LIGHT
TWO KINDS OF LIGHT SOURCES
•The NATURAL SOURCE
SUN MOON / STARS FIRE
DEFINING LIGHT
TWO KINDS OF LIGHT SOURCES
•The ARTIFICIAL SOURCE
The invention of lamps and electricity changed the course of man, it’s
built environment and it’s activities.
DEFINING LIGHT
TWO KINDS OF LIGHT SOURCES
•The ARTIFICIAL SOURCE
•LAMPS
•ELECTRICITY
•LIGHT CONTROLS
Architecture @ daytime
LOUVRE MUSEUM,
PARIS
Architecture @ night!
TOPICS OF OUR STUDIES
History of Lighting
Terms & definitions
Light sources and architecture
Luminaires or Light Fittings
Basics Lighting Design Concepts
Lighting Design Application
TERMS & DEFINITONS
Accent Lighting: Focusing light in a particular space or object. Intended to
create visual interest in an area or object. Subject of focus.
Alternative Current (AC): Electric Current in which the flow of electric
charge reverses direction at regular intervals.
Ambient Lighting : Usually use as general light to illuminate the entire
space or area.
Amps (A): Standard Unit of measurement of electric current.
Ballast : A device used to regulate current and voltage to start and operate
a lamp. Ballast are used with HIT and Fluorescent lamps.
Candela (cd): Measurement of luminous intensity of a source in a given
direction.
Center Beam Candela Power ( CBCP): Luminous intensity at the center of a light
source beam.
Color Rendering Index ( CRI): A measure of a light source ability to show the
colors accurately. The scale is from 1 -100. Sun= 100 CRI
Color Temperature: Correlated Color Temperature (CCT). A measurement of
hue of the light produced by a lamp source. ( Cool white, warm white, Day light)
Control Gear: A collective term for electrical disconnect switches, fuses,
and circuit breakers used to control, protect and isolate electrical
equipment.
Cut-off angle : Means the angle, measured up from the nadir, between the
vertical axis and the first line of sight at which the light source is not visible.
Diffuser: A device used to alter light by scattering it in order to create a softer
light with minimal glare.
Dimmer : A device used to control the light output of a light source.
Direct Current : Electrical current that flows in only direction without cycling. DC
current is most commonly used with batteries and PV cells.
Direct Replacement : It’s a simple as Plug-N-Play ! Direct replacement LED lamps
OEO crew into existing fixture without the need to rewire or upgrade while
helping save energy costs up to 84%.
Driver: Electrical or electric circuit the controls other components. LED Lighting
Systems, the driver regulates the power of the LEDs.
Efficacy: Lumens per Watt of the light source.
Electromagnetic Interference : Disruption of an electronic device by an external
source by electromagnetic induction , electrostatic coupling or conduction.
Electronic Ballast: Ballast composed of electronic components instead of the
core and coils transformer. Electronic ballasts do not experience as much power
loss as magnetic ballast.
Fluorescent Lamp: Low pressure Mercury-Vapor-Gas-Discharge Lamp that uses
fluorescence to produce visible light.
Flux: Measure of the number of electro-magnetic filed lines passing through a
surface in a given amount of time. Commonly used to measure or calculate
illumination levels.
Halogen Lamp : Is a type of incandescent lamp that incorporates halogen in
order to increase the average life and light output of the light source.
Heat Sink: A device that disperse heat in luminaires, usually used in LED to
disperse heat away from the LED.
Hertz: The standard unit of measurement for frequency . One Hz equals one
cycle per second.
High Bay: Type of Light Fixture typically used for commercial and Industrial
applications with high ceilings ( > 20ft – 6meters).
High Intensity Discharge Lamp (HID) . Metal Halide Lamps are family of
electrical gas-discharge lamps that produces light by means of electrical arc.
High Pressure Sodium Vapour Lamp : Type of HPS used in streets and outdoors
lighting applications.
Illuminance (E): The amount of light or luminous flux arriving on a surface. It is
measured in lux “ lx.
