Disclosure: We may get commissions for purchases made through links in this post.
One of the least-understood aspects of home lighting is the role played by light diffusers and how they differ from standard light fixtures and lampshades. Light diffusers are specifically designed to reduce the glare from light bulbs and spread out illumination evenly over an area. They also protect the light bulbs they cover, and they can enhance the appearance of light fixtures by concealing unsightly bulbs.
Light diffusers are translucent or semi-transparent covers made of glass or various polymers. They typically cover the bottom and/or sides of a light fixture. Their primary purpose is to spread out or scatter the light produced by the fixture's bulbs to achieve even illumination. Diffusers control brightness, soften the emitted light, and can add a relaxing, homey feel to a room. They are especially useful in softening the harsh light of fluorescent and LED bulbs.
In this article, we'll discuss the five materials most commonly used to make light diffusers:
- PC (polycarbonate)
- PMMA (polymethyl methacrylate)
- PP (polypropylene)
- PS (polystyrene)
We'll also examine seven types of light diffusers that are the most useful in home settings:
- Hanging ceiling-mounted light diffusers
- Flush-mounted ceiling light diffusers
- Ceiling-mounted fluorescent light tube diffusers
- Panel fluorescent light tube diffusers
- Wall-mounted light diffusers
- Lens diffusers for under-cabinet lights
- Wraparound fluorescent light diffusers
Please keep reading as we delve further into this topic! You'll soon know exactly which light diffuser is ideal for any room and light fixture in your home.
Materials Used In Light Diffusers
Traditionally, glass was the go-to material for light diffusers, but over the past twenty years, advances in polymer technology have led to the development of lighter, cheaper, and more durable options. We'll discuss the pros and cons of each below.
Until recently, milky-white and frosted glass were the most common materials used to make light diffusers. Both spread light evenly, but with a frosted glass diffuser, the light bulbs are visible. In comparison, milky-white diffusers conceal bulbs better. Of course, glass does an excellent job of transmitting light, so glass diffusers are efficient. However, they are also heavy, easily breakable, and more expensive than other options. They are still popular with homeowners because they are much more attractive than the polymer (plastic) alternatives.
Many light diffusers today are made of polycarbonate. The material is thin, light, and flexible, so it's easy and cheap to manufacture. It resists breakage and is fire-resistant, making it an excellent choice for fixtures with LED lights, which tend to be very hot. On the negative side, PC diffusers scratch easily, and they are vulnerable to UV rays, so you should not use them outdoors.
PMMA (Polymethyl Methacrylate)
PMMA is useful in situations when polycarbonate should not be used. It's weather-resistant and is not affected by UV rays, so PMMA diffusers are excellent for outdoor use. Polymethyl methacrylate has the best optical properties of all the polymer options. However, it is much more prone to breakage than polycarbonate, it is flammable, and it is not resistant to temperatures above 93 degrees. It's best used with fluorescent lights, which emit less heat than LED or incandescent bulbs do.
Polypropylene is a fairly new form of plastic in light diffusers. While PP light diffusers have not been around long enough to stand the test of time, users so far are finding them to be tough, good at transmitting light, and less prone to absorbing dust than other polymer options. Like those shown below, PP light diffusers commonly attach to the bottoms and/or tops of lampshades.
Polystyrene light diffusers were, in previous decades, the major alternative to glass. They continue to be popular, although they have some drawbacks that the other polymer options don't. Specifically, PS tends to yellow over time and is more brittle than PC, PMMA, and PP. However, PS is low-cost, resistant to scratching, and resistant to dust.
7 Types Of Light Diffusers
Where might you want to use light diffusers in your home? Think of areas where you need ambient light, but you don't want harsh illumination: the living room, dining room, and bedrooms. Also, anyplace where you have fluorescent lighting, you may want diffusers to soften the bulbs' harshness and flickering. In the following section, we'll look at the seven most common uses of light diffusers in the home and where you might use each.
1. Hanging Ceiling-Mounted Light Diffusers
Many living rooms, dining rooms, and bedrooms have one central ceiling light, often using traditional incandescent light bulbs or LEDs. You want to evenly illuminate across the whole area in these rooms, and you may have stand lamps or table lamps available for task lighting when needed. So, choosing a ceiling-mounted hanging light fixture that includes a built-in light diffuser is an excellent option. The example below shows how a glass diffuser covering the bottom of the fixture spreads illumination, eliminates the naked bulbs' hash glare, camouflages the bulbs, and adds a classy look.
2. Flush-Mounted Ceiling Light Diffusers
Flush-mounted ceiling light diffusers are common in kitchens and bathrooms. They often cover recessed fixtures with fluorescent or incandescent bulbs. They provide a soft white ambient light for the whole room. You may choose to supplement them with task lighting in specific areas of the room, bright lights around the vanity mirror in a bathroom, for example. Flush-mounted ceiling light diffusers are typically made of PC or PMMA.
3. Ceiling-Mounted Fluorescent Light Tube Diffusers
If you have ceiling-mounted fluorescent light tubes in your home, the fixtures will come with milky-white or clear polymer diffusers. These are typically made of PC or PMMA or, in older models, PS. Ceiling-mounted fluorescents are much less common in homes now than they were in the 1970s and 1980s. However, you may still find them in areas where attractiveness is less important than bright illumination, such as basements, workshops, closets, and laundry rooms.
4. Panel Fluorescent Light Tube Diffusers
Panel-style diffusers typically cover fluorescent lights recessed behind a dropped ceiling. Many older homes have dropped ceilings to lower heating costs or cover damage to the original ceilings. Instead of leaving gaps in the new ceiling where the light bulbs are, many homeowners put up polymer diffuser panels instead. These diffuser panels are usually clear or white, but there are some more decorative options, like the one below.
5. Wall-Mounted Light Diffusers
Wall-mounted light diffusers are typically used outdoors to illuminate patios, walks, or doors. Glass and PMMA are the most common materials used in outdoor light diffusers because both are resistant to UV light and weather. Glass diffusers come in a wide variety of colors and styles, and their price varies accordingly. PMMA is a standard translucent white and tends to be less expensive; however, it also lacks glass's charm and attractiveness.
6. Lens Diffusers For Under-Cabinet Lights
Many kitchens and work areas feature under-cabinet light fixtures. These usually use either fluorescent or LED bulbs. They are typically covered by lens diffusers -- L-shaped pieces of molded polymer -- that protect and hide the bulbs. If you are using fluorescent bulbs, then you can add PC or PMMA lens diffusers. LED bulbs, however, are much hotter than fluorescents, so you should not use PMMA diffusers with them.
7. Wraparound Fluorescent Light Diffusers
In workshops, garages, and outdoor areas, you may find hanging fluorescent light fixtures with diffusers that wrap around the bottom and both long sides of the bulbs. These wraparound light diffusers are typically made of PMMA or PS, both of which are resistant to wear and scratching. PS also has anti-static properties and does not collect dust, so it is particularly useful in workshop settings.
As you plan the lighting in your home, keep in mind places where you'd like gentle, even ambient light. For rooms where the appearance of your light fixtures matters, such as the living room and bedrooms, you might choose to add an attractive glass diffuser to the bottom of a ceiling light.
In areas where you don't want a light hanging down from the ceiling, like bathrooms and kitchens, consider installing a flush-mounted diffuser. For outdoor use, a wall-mounted light diffuser may be optimal. And to soften the harsh light from fluorescent tubes, add a panel, lens, or wraparound diffuser.
You may also enjoy the following: