Lighting Flashcards
(65 cards)
Which part of the eye is the:
a. light-sensitive surface where the image is projected onto at the back of the eye
b. coloured portion that functions as a diaphragm to control the amount of light entering the eye
c. opening in the centre of the is where light enters the eye
d. transparent capsule behind the iris that is used to focus the image
A) Retina
B) Iris
C) Pupil
D) Lens
State the four main factors considered to affect visibility.
Size , brightness, contrast, Time
Which one of the preceding factors is most important when viewing moving objects?
Time
What two important features does a good lighting system provide?
Brightness, Contrast
Using the electromagnetic spectrum, which is the higher frequency light: infrared or ultraviolet
Ultraviolet
The actual colour composition of white light can be seen using a
Prism
The human eye is considered to be most responsive to colour range of:
a. purple
b. red
c. orange-red
D. yellow-green
Yellow-Green
- The “colour” of light is determined by its
Wavelength
The total light output of a lamp is measured in
Lumens
The unit for illumination is the
Lux (Lx) EV
What two values does efficacy compare?
light output (lumens)
and pover input
Which of the following types of lamps is considered to provide the best colour rendition?
a. incandescent
b. mercury vapour
c. high-pressure sodium
d. fluorescent -cool white
Incandescent
Which of the following light sources is generally considered as having the highest efficacy?
a. incandescent
b. fluorescent
c. mercury vapour
d. high-pressure sodium
High Pressure Sodium
The lighting level on a work plane is commonly measured using a
Photometre
In simple terms, state what is meant by the:
A) Inverse square law
B) Cosine law
A) Illumination is inversly proportional to the square of distance between them
B) The ilumination of any surface varies as the cosie of the angle of incidence, Angle of incidence is between the normal to the surface and the direction of incident light
- When referring to wavelengths of light, what is a nanometre?
A nanometre is one billionth
of a metre
The two main factors in the design of a lighting system involve both the
Quantity of light and quality of light
- List three variables (factors) involved in the design of a lighting installation.
Area and type of enviourment (indoors or outdoors)
Type of Task (critical seeing or decoration)
Architectural requirements
Costs of installation
Availability
Environmental impact
What are three factors that contribute to the quality of light?
Glare
Diffusion
Colour
What two colours are considered to be “cooling”?
Blue and green
A complete lighting unit (lamps, reflectors, etc.) is called a
Luminaire
What does a distribution curve illustrate?
The variation in light density, usually througha vertical axis
What are two important considerations for roadway lighting design?
CRI, and light level
What lamp type does not start (light up) immediately?
HID High Intesity Discharge
