Kaplan- Lesson 7: Lighting Flashcards
What part of the eye is the focusing device?
The lens
What part of the eye is the device that controls the amount of brightness of the light admitted to the eye?
The iris
In regards to the retina in an eye, what are the two types of nerve pickups and what do they sense?
The cones- sense colors
The rods- sense black & white
The measure of how well light actually shows true color is called ______.
The color rendition index (CRI)
The amount of light put out by a source is called ______. What is the unit of measure?
The intensity.
Candlepower (cp)
The amount of light flowing through an area is called _____. What is the unit of measure?
Flux.
Lumen (I)
The amount of light arriving on a surface is called _____. What is the unit of measure?
Illumination.
Footcandle (fc)
The amount of light leaving a surface would depend on its reflectivity and would give a measure of how bright it looked, or its ______. What is the unit of measure?
Luminance.
footLambert (fL)
What are the three general categories of artificial lighting?
incandescent, fluorescent, and high intensity discharge.
A(n) _______ lamp or bulb contains a filament, usually a tungsten alloy, which is heated by passing an electric current through it.
incandescent
T/F Incandescent lighting is the least efficient type of artificial light.
True.
It is also characterized by a short life-time for individual bulbs.
_______ lighting passes a current through gases inside a glass tube. This releases energy in the form of free electrons and gas ions.
Fluorescent.
Fluorescent fixtures consist of a lamp and _____ that controls the voltage and the current to the lamp.
a ballast
Lamps that consist of a lamp within a lamp which is run at a very high voltage.
High intensity discharge (HID)
What are the four general types of HID lighting?
Mercury Vapor Lamps
Metal Halide Gas Lamps
High Pressure Sodium Lamps
Low Pressure Sodium Lamps
Which of the four types of HID lighting is the most efficient?
High Pressure Sodium Lamps- 110 lumens per watt
Which of the four types of HID lighting is the best for security lighting?
Low Pressure Sodium Lamps
The method for calculating lighting levels that works best for a single fixture, or small number of fixtures. It takes careful account of orientation and distance but ignores surrounding reflection.
Point Grid Method
The method for calculating lighting levels that is based on distribution of a large number of fixtures, and takes into account the reflectivity of the ceiling and walls, and the comparative volumes of the top, middle, and bottom of the room.
Zonal Cavity Method
The method (developed in the US) to measure the amount of daylight calculated by three locations in a room : 5’ from the window, the middle of the room, & 5’ from the back of the room.
The Lumen Method (or flux method)
The method (developed in Europe) to measure the amount of daylight calculates the daylight at any location in a room. It expresses the amount of light at an interior location as a percentage of the light available on an exterior surface.
The Daylight Factor Method
Which color represents the highest Kelvin temperature and the shortest wavelength?
A. Red
B. Yellow
C. Green
D. Blue
D. Blue
What is the name of the sensing surface of the eye?
A. Lens
B. Iris
C. Retina
D. Cilia
C. Retina
Which of the following statements about glare are true?
I. Glare is always a reflection
II. Glare is always an extreme contrast in brightness.
III. Glare is always a very high illumination
A. I only
B. II only
C. III only
D. I, II, & III
B. II only
Glare is always an extreme contrast in brightness.
A material which transmits light without transmitting the images on the far side is called
A. transparent
B. translucent
C. opaque
D. reflective
B. translucent
Which of the following statements are correct about the term diffuse?
I. Ambient light is usually diffuse.
II. A mirror is a diffuse reflecting surface.
III. Printing or writing is easiest to read when viewed in diffuse light.
A. I & II
B. II & III
C. I & III
D. I, II, & III
C. I & III
I. Ambient light is usually diffuse.
III. Printing or writing is easiest to read when viewed in diffuse light.
What is the unit which measures the amount of light striking a surface (the illumination)?
A. Candlepower
B. Lumen
C. Footcandle
D. FootLambert
C. Footcandle
If a lamp of 2400 cp intensity results in an illumination of 24 cp at 10 feet, the illumination at 20 feet is _____.
E = I /d^2 24 = 2400 / 10^2 E = 2400/ 20^2 E = 6
The major advantage to low voltage incandescent lamps is that the lamps
A. are much brighter for a given wattage.
B. last much longer.
C. focus and aim their light more accurately.
D. can run at higher temperatures.
C. focus and aim their light more accurately.
What is the diameter of an R-40 bulb?
A. 2.5”
B. 3.2”
C. 4”
D. 5”
D. 5”
40 x 1/8 = 5
Which of the following are true about fluorescent lighting?
I. Fluorescent lighting is more efficient than incandescent lighting.
II. Fluorescent lighting can have different CRI ratings, depending on phosphors.
III. Fluorescent lighting does not run on 12 volt DC current.
A. I & II
B. II & III
C. I & III
D. I, II, & III
D. I, II, & III
