Light fixtures (or “luminaires”) control and distribute light in different ways. Shielded light fixtures are among the ways that this can be accomplished. The reasons to use them are as follows:
- Reduce glare
- Diffuse light
- Protect and/or hide lamps
- Enhance fixture appearance
There are three different types of shielded light fixtures:
Diffuser – This is a translucent or semi-transparent cover that spreads out or scatters light. Using a diffuser will control brightness and give off a soft light relative to the lamps being used. They are typically made of glass or plastic and are used on the bottom or sides of a light fixture. They are typically used in offices or schools where there is a lower ceiling height.
Here are some examples of fixtures that use diffusers:
Lens – This is a clear or transparent cover. Two types or commonly used lenses are as follows:
Prismatic – These are shaped with an arrangement of small refractive components on one side for excellent light diffusion and glare reduction.
Here are some examples of fixtures that use prismatic lenses:
Polycarbonate – These lenses are extremely durable and are ideal for harsh environments. They are typically used with vapor tight fixtures used in wet or dusty areas.
Here are some examples of fixtures that use polycarbonite lenses:
Parabolic Louver – These are baffles that utilize an open grid pattern with parabolic reflectors in each cell of the grid. They are excellent for directing light downward and reducing glare from the fixture. Size and depth of a louver will affect light output and distribution.