After various user-tests the caustic effect inside the aquarium was still considered to be too dynamic. As stated above, the caustic effect can be reduced by increasing the source size. The virtual source size may be increased by applying a diffuser in front of the source.
The cover plate abrasion is tuned to scatter the light just slightly, in order to provide an increase in source size without compromising (i) the optical efficiency, and (ii) the beam cut-off needed to suppress disturbing caustics outside of the aquarium.
With CoralCare Gen 2, four carefully placed clear areas (Figures 6 and 9) were added in the glass plate. These clear areas allow the light emitted by four white LED’s to directly exit the glass plate, adding some extra sharp dynamic light effects on top of the homogeneous blanket of diffuse light. Because only the 4 white LED’s can directly penetrate the glass plate, the caustic patterns have a natural warm color point. The link between caustic pattern and the color point is inspired by the natural effects in the ocean. At noon, when the sun is at its highest point, the light creates sharp caustic patterns on the ocean floor. During this time the light has its shortest travel distance through the water before it arrives at the ocean floor (Fig 8.1,8.2). It is known that the longer the light travels, the bigger part of the spectral content (especially the green/red colors) is absorbed. Therefore, the warmest color point is linked to this period of the day. During the evening, the travel distance increases (creating a more blueish color point in the water) and the light is scattered further. The scattering patterns caused by the sun are drastically reduced.