(Updated 01.06.2020: complete edit of the article) Lighting in the main habitat will consist of different modes: standby, activity, emergency and disinfection. This section should explain the ideal system of lighting inside the underwater habitat.
All premises are equipped with motion sensors. Although LED lighting consumes very little energy, it is not necessary for full lighting to be switched on when no one is in a room. During this time there should still be minimal lighting to ensure full visibility for the camera system. The decision as to whether this lighting should only be switched on when needed is still pending. For standby lighting a standard LED of 5 W should be sufficient.
For the case that this standby bulb is broken while the habitat is not in use, an automatic replacement and its technical system should be considered from the beginning.
Activity (presence of aquanauts)
Whenever an aquanaut enters a room, the motion detectors should switch to ‘activity’ mode, containing a set of lights that sufficiently illuminates the whole room. After a certain time of inactivity (assumed as absence of aquanaut) these lights should be turned off, while, of course, this reaction time should not deceed average periods of inactivity of a person.
It still has to be discussed if it makes sense to switch lighting to red as soon as the conditions for an emergency are detected and applied by the IT system or manually by the aquanauts, in order to accustom the aquanauts eyes to the potential darkness outside the habitat during evacuation. At the same time there should still be enough light to try to figure out the reason for the emergency and apply counter measures.
Especially after the Covid-19 outbreak there have been several approaches how to disinfect public areas like hospital rooms or busses sufficiently. One of them uses UV light, that is applied 4 or 5 minutes inside a public bus to disinfect it from viruses. It is known that blue light prevents bacterias and mould.
It seems reasonable to apply blue/UV light for disinfection once or several times a day during inactivity in that specific room. This mode can be activated/deactivated automatically. Details have to be further discussed.
Blue lights and UV lights are cheap products that can be easily purchased.
Further read on the subject:
- US National Library of Medicine – National Institutes of Health
- Frankfurter Allgemeine Zeitung (German): UV-Licht gegen Viren
The Virtual Sky of Fraunhofer Institute
In 2012 Fraunhofer Institute succeeded to build an electronic ceiling imitating a window to the sky. This might be a good technology for long stays at the Undersea Station.
Translation of the Fact Sheet: ‘Virtual Sky is a dynamic, multi-spectral light ceiling. The prototype in the laboratory of the Fraunhofer IAO covers an area of 34 m² and integrated a total of 34,560 LED with four different colors. Like this more than 16 million colors can be represented. They are grouped in a total of 240 (20×12) individually controllable squares (30 x 30 cm) that can be directed just like display pixels. Both temporally and spatially dynamic lighting is possible.
The diffuse illumination of VirtualSky is complemented by a total of 350 warm white LED with focusing optics for targeted direct lighting. The picture shows the spectra that arises with the white LED, RGB LED, and the combination of both at full power. At full power illuminance of about 3000 Lux can be achieved. The spectra can also be adjusted to be very close to the daylight spectrum. For example: with a color temperature of 5600 K a color rendering index of Ra > 95th can be reached. The color temperature can be infinitely set to a range between 1500 K to 27 000 K. The dynamic control (max. 30 Hz) allows to project videos of passing clouds or simulate a sunrise in the Aegean.
In addition it is possible to adjust the light control adaptively, individually and interactively according to the user. That individual cells can be illuminated in such way that the light follows the user when changing his location.
The maximum in the blue areas of the spectrum with the RGB LED lies at 462 nanometers, with the white LED at 448 nanometers. The intelligent control system allows a more or less strong circadian efficacy with constant color temperature.
VirtualSky and its various influences of artificial light can be examined to humans. From the research results recommendations for a healthy lighting and optimal working conditions can be derived.’
CoeLux – Mimic Natural Refraction Processes
There are several different approaches to mimic natural daylight. CoeLux claims to have developed a product that succeeds this task. For details follow the following links:
- CoeLux Homepage
- Web Urbanist: New Artificial Lighting Tricks Human Brain into Seeing Sunlight