Ch. 15 Lighting Flashcards
Defined as visually evaluated radiant energy
Light

A form of electromagnetic radiation with wave links that range from about 400nm for violet light to about 700 nm for red light
Visible light
This type of light is produced when I store cement approximately equal quantities of energy over the entire visible spectrum
White light
The unit is luminous intensity approximately equal to the horizontal light output from an ordinary wax candle. In SI system of measurement, this unit is the Candela
Candlepower cp
The unit of luminous flux equal to the flux in a unit solid angle of one steradian sr in a uniform point source of one candle power. On a unit sphere, and area of one square foot will be submitting an angle of one sr. Because the area of a unit sphere is equal to four pi square units, a source of one candle power produces 12.57lm
Lumen lm 
The density of luminous flux incident on a surface in lumens per unit area. One lumen uniformly incident on one square foot of area produces an aluminates of 1 foot candle. In SI units the measurement is lux lx, or lumens per square meter
Illuminance
Believe it is flats per unit of projected area and unit solid angle leaving a surface, either reflected or transmitted. By definition, the unit is the candela per square meter, also called the net. In the older inch – pound system, the unit is the footLambert, where 1 foot Lambert is 1/pi cd/sf. This takes into account the reflectance and transmit its properties of materials and the direction in which they reviewed. Thus, 100 lx striking a 1 m² service with 50% reflectance result in aluminate of 50 cd per square meter. This is sometimes called brightness, although brightness includes the physiological sensation of the adaptation of the eye, whereas this is measurable state of object luminosity
Luminance
The solid angular flux density in a given direction measured and candlepower or candelas
Luminous intensity
What is luminance also sometimes called
Brightness
What is the category in which various activities are assigned and I’m gonna minutes category
A-y A represents the lowest value for general lighting in non-critical areas, Y represents requirements for specialized and difficult visual tasks
To conserve energy most codes require designers to develop a power budget for a project based on the building type and design lighting systems within that budget. What does this mean for determining illumination per category
This most often requires that the recommended illumination level be provided for task areas only and that general background illumination or ambient light be less, about 1/3 of the task level.
What is considered a maximum power budget for many commercial buildings
2.3 W per square foot
What are some important qualities in light
Glare, contrast, uniformity, and color
What are the two types of glare 
Direct glare and reflected glare
This type of glare results when a light source in the field of vision causes discomfort and interference with the visual task. Not all visual light sources caused his problem. The extent of the problem depends on the brightness of the source, its position, the background illumination, and the adaptation of the eye to the environment
Direct glare
Is factor is the percentage of people who, when the rain from his classified location and in a specific direction, will find the situation acceptable in terms of discomfort glare. Although the calculations are complex, so I’m simplifications are made, and many manufactures publish this rating for their light fixtures when used under certain conditions
Visual comfort probability factor VCP
For most situations what is the critical zone for glare
In the area above a 45° angle from the light source
This type of glare occurs when a light source is reflected from a viewed surface into the eye. It is this that interferes with the viewing task, it is also called a veiling reflection. The effect of this is to decrease the contrast between the task and its background. For example, a strong light on paper with a pencil writing can bounce off the reflective graphite, making the graphite almost as bad as the paper, and effectively obliterate the writing
Reflected glare
The difference in illumination level between one point and nearby points.
Contrast
Invert situations what should brightness ratios be limited to
3 to 1 between task and immediate surroundings, 5 to 1 between task in nearby general surroundings, and 10 to 1 between task and more remote surroundings
Affects a persons perception of a space is being comfortable and pleasant to be in. This is usually not desirable except for certain tasks like drafting or machine shop work. Some amounts of shade and shadow provide highlights in interest to the space
Uniformity
The interaction between the color of the light source in the color of the objects that reflect the light. This is a complex subject, but it can affect peoples comfort and their impression of an environment.
Color in lighting
What are the four types of light sources in addition to daylight
Incandescent, fluorescent, high intensity discharge, and light emitting diode‘s LED
The ratio of luminous flux emitted to the total power input of the source and is measured in lumens per watt. It is an important measure of the energy efficiency of a light source. The amount of heat generated by light sources also an important consideration because waste heat usually needs to be removed or compensated for with the air conditioning system, which can add to total energy of the building
Efficacy
Consists of a tungsten filament placed within a sealed bowl containing an inert gas. When electricity is passed through the lamp, the filament glows, producing light. These are produced in a variety of shapes, sizes, and wattages for different applications. These are designed by their shape followed by a number that indicates the diameter in eighths of an inch at the widest point. That’s an R – 38 is a reflector lamp with a diameter of 4 3/4 inch
Incandescent
What is an a incandescent light
Arbitrary
What is a G incandescent light
Globular
What is CA INCANDESCENT 
Candle shaped
What is a PS incandescent light
Pear-shaped
What is an MR incandescent light
Multi faceted mirror reflector
What is a PAR incandescent light
Parabolic aluminized reflector
What is an R incandescent 
Reflector
What is an S incandescent light
Straight
What is a T incandescent light
Tubular
What type of bean spread does a reflector lamp have
Widespread
Provide some more efficient throw a flight from a fixture by focusing the light being at a point slightly in front of the land before it spreads out. It’s spread a slightly smaller than that of a regular reflector light.
Elliptical reflector lamp ER
Focuses light in a tighter spread, with the light rays more parallel because its reflector is a parabola with the filament at the focus of the parabola this comes in blood spread and spotlight
Parabolic aluminized reflector lamp
What types of beam spreads do you parabolic aluminized reflector lamps and reflector lamps have
Flood spread and spot light
Please type is the low-voltage it has the narrowest beam spread of the four types of incandescent lamps
MR – 16
A multi faceted mirror reflector low voltage lamp
MR-16
What are the disadvantages of incandescent lights
They are low efficiency, have a short lamp live, and high heat output. The combination of heat production and low efficiency makes these lamps on desirable for large, energy efficient installations