Home > U Education
Sort By:
Page of 1
The Basics of Bulb Bases The Basics of Bulb Bases

We are sure you know there is a lot of information you need when shopping for light bulbs. Watts, lumens, kelvins, CRI, and even hours are all things you will need to know. The most important thing to know when buying a bulb might be the simplest of all, the base. Even if you get everything else just right, a bulb with the wrong base for your fixture will leave you in the dark every time.

If you are looking for bulbs in your home, chances are you will use Edison screw light bulbs, whether they are incandescent, compact fluorescent (CFL), or even newer LED bulbs. There are four common types of Edison light bulb bases, Medium, Mogul, Intermediate, and Candelabra. It’s easy to know which is which, as each will be labeled on the packaging with E (for Edison) and the diameter of the bulb base (in millimeters).

Medium (E26) base are the most common type of Edison screw base. Medium bases are used with standard A19 shape incandescent, CFL, and LED. The majority of table lamps and bathroom fixtures will take bulbs with medium base. Mogul (E39) base are used for high voltage metal halide and high pressure sodium bulbs. Intermediate (E17) base bulbs are uncommon, but are used in some appliances and in some specialty decorative bulbs. Candelabra (E12) base bulbs are used in many decorative fixtures, such as chandeliers.

Full Spectrum Lighting Full Spectrum Lighting

Full spectrum lighting is a term used to describe light that uses all of the different wavelengths of the color spectrum. Natural daylight (sunlight) is considered full spectrum lighting although the range is affected by the time of day, cloud cover and tilt of the earth. Full spectrum is a word used in the lighting industry to suggest that a bulb will produce a natural light. While color temperature and the color rendering index (CRI) are the standards for measuring the color production of a light bulb, full spectrum lighting is simply an all inclusive catch phrase.
Many artists use full spectrum bulbs in their studios so that their paint colors stay true to form when moved into a gallery or home. Color matching specialists use full spectrum bulbs to ensure paint tints come out okay when mixing indoors. Full spectrum lighting can also help indoor gardens and nurseries by simulating natural daylight. One of the other common uses for full lighting spectrum is to help treat seasonal affective disorder (a disease that causes deep depression due to the lack of sun light). This disorder is common in parts of the country like Alaska where there is little daylight for months at a time. So now when you see the term “full spectrum,” you’ll know exactly what it means.

Lighting Lingo Lighting Lingo

Often times we casually throw around words thinking we know exactly what they mean when in fact they have different definitions all together. In lighting, this can be true with three similar terms that have three very different meanings. So sit back, relax and just let me explain just why lamps, lighting fixtures and luminaires are closely related but not interchangeable.


A lamp is commonly referred to as the light bulb. Essentially a lamp and a bulb are the same thing, as long as it produces light from electricity. The base of these lamps (or bulbs) usually have a component of aluminum or brass (a better conductor because aluminium can fuse to the socket itself) at the bottom which helps conduct an electrical current through the socket of a light fixture.


Light Fixtures

Speaking of light fixtures, they are what are sometimes referred to as lamps (such as floor lamps, desk lamps and table lamps). See where this can start to get a little confusing? These terms are often interchanged with each other but don’t necessarily mean the same thing because light fixtures are devices that create light when a lamp is screwed into its socket.


However, it is only a light fixture without a lamp. With a lamp and an electrical charge to create light, it becomes a luminaire. So, a lamp plus a light fixture equals a luminaire. It really just comes down to simple math!