Skylight Technology

Collimating Tubular SkylightEntech Solar's tubular skylight redirects natural light from all parts of the sky to the work area beneath the skylight with unprecedented optical efficiency. This redirection of the light from all parts of the sky is called collimation.  Previous skylights lack this collimation feature and deliver much of their light output outside of the desired work area beneath the skylight. Previous skylights are also inefficient, due to the large number of reflections required to deliver high-incidence light to the interior of the building. Entech Solar's skylight unit overcomes both of these deficiencies of prior skylight technologies.

The Collimating Feature The basic function of the collimating section is shown in the sketch below. Rays of natural light can enter the skylight from all directions. In more technical terms, this means the rays can have an incidence angle of zero to 90 degrees, as shown by the different color rays in the sketch above. After a few reflections, these rays are collimated to emerge at much smaller angles - less than 30 degrees, as shown in the sketch. Thus the new skylight places the output light where it belongs, beneath the skylight, unlike earlier tubular skylights that do not control the output angles of the rays. This enables the lighting system designer to control the illumination pattern within the workspace, rather than accepting whatever nature provides. Stated more simply, if Entech Solar's skylight is placed over your desk, it will illuminate your desk, and not your computer screen in the corner or your neighbor's office. Entech Solar's tubular skylight redirects natural light from all parts of the sky to the work area beneath the skylight with unprecedented optical efficiency.

The collimation feature also allows the new skylight to use diffusers more effectively to eliminate glare and to provide uniformly pleasant light to the work space. With a special diffuser at the top of the skylight above the roof, and another at the bottom of the skylight in the ceiling luminaire, a beautiful, smooth, full-spectrum illumination profile is provided under all sky conditions. While the intensity varies with the sun's position and cloud conditions, the illumination pattern remains smooth and pleasant.