The relationship between light and design has been long and fertile. New opportunities have been explored using medical light by architects, interior and industrial designers to improve wellbeing. Dr Norman E. Rosenthal explains in his book ”how to overcome seasonal affective disorder”, reference that, in the dark days of winter where symptoms of SAD are worse; the use of light boxes or special light fixtures have been successful in treating the symptoms of SAD. There are advanced light boxes that can replicate outdoor light levels and are used to help with depression, sleeping problems and poor appetites brought on by SAD. There are remarkable companies which specialise in therapeutic lighting that treats symptoms of SAD. These are usually smaller light boxes that are cheaper and more widely advertised, which also appear to be quite popular in the market.
In 2012, Philips was the largest manufacturer of lighting in the world and Philips lighting (formerly Philips Medical Systems), is the top companies that develops lighting products, which promote wellbeing in the home and workplace. Also Phillips has a varied range of light simulators designed to treat the symptoms of SAD. One of the newest lighting products from Philips, treats difficulties in falling asleep and waking up. The ”Somneo Sleep and Wake-up Light” (See Figure 2) simulates sunrise for a natural wake-up and sunset to help users fall asleep with additional natural sounds for relaxation.
The Dawn Simulator by Phillips produces a light intensity of three hundred units of luminance, but this product doesn’t fully treat the symptoms of seasonal affective disorder, and cannot be classified as a medical light for SAD. According to the SAD organization a Dawn Simulator is an excellent device for promoting waking the user up gently in the morning and an aid for sleeping at night. It can also play relaxing sounds to calm the user when stressed and the portability of the product allows users to take it with them and put it in their offices.
Light therapy boxes produce a higher luminance range between 1,000 and 2,500 lux, because the treatment of SAD requires brighter light, which is more effective to treat the Symptoms of SAD with. The intensity of light affects the treatment of symptoms of SAD and is measured in units of luminance called lux. The light has to be close to the amount produced by the sun, which is usually around 10,000 lux. This amount increases in the summer up to 100,000 lux. Dr Norman E. Rosenthal explains in his research on the treatment of SAD that 2,500 lux is considered to be therapeutic, and also the higher level of light intensity is, the shorter the amount of time each daily treatment of SAD is.
The Litepod Company has worked alongside the NHS since the 1980s to develop a medical therapy light to help people who suffer from seasonal affective disorder. Their medical devices produce the best quality of therapeutic light, replacing the old traditional SAD lights. The Litepod Diamond Light box offers full spectrum treatments that can take only fifteen minutes to an hour. The SAD organisation considers the ”DIAMOND 2 SAD LIGHT” (See Figure 3), by the Litepod Company to be the most affordable and effective treatment for the symptoms of Seasonal Affective Disorder.
Dr Norman E. Rosenthal explains in his research on Light therapy, that you can get the full benefit of a light box by setting the light box up in a suitable place at work or home and sitting in front of the light box for between twenty minutes to an hour every day, but it is unnecessary to stare at the lightbox for long period of time to get its full benefit. There can also be side effects of having light therapy, which can be mild but include: headaches, eyestrain, anxiety, over activity, insomnia, Fatigue, dryness of the eyes and reaction of the skin that is a type of Sunburn. Typically the side effects of the therapy light are more commonly Headaches and Eyestrain.
There are two types of lights that treat SAD, a White light and a Blue light. The difference between these lights is that blue light technology can be found in some of the SAD light therapy products like the ”Bluelight solution” (See Figure 4) by The Litepod Company, and the White light is found mainly in Therapeutic Light Boxes. The research behind the application of blue light into light therapy products, shows that blue light gives effects such as boosts of alpha wavelengths, which develop alertness and reaction time including improvement in our mood. According to an article by David C. Holzman on ”The Unique Human Health Effects of Blue Light” the effect is produced by the blue light wavelengths. Researchers at leading US Medical Universities and the National Institute for Health (NIH) have found that a blue wavelength obtains an effective response from sufferers of SAD and other circadian rhythm related disorders.
The light produced by the sun is white and is made up of the full spectrum of the colour. This can be seen when sunlight shines through rain and is split into the spectrum of colours by refraction and is seen as a rainbow. The reason light boxes use white light is to attempt to replicate sunlight because of the high unit of luminance that sunlight has which is around 10,000 lux. As a result the white light gives the user a more positive response when they lack sunlight.
Research into blue light, shows that particular wavelengths of blue light are more effective at treating SAD. Dr Norman E. Rosenthal also explains in his research that specific wavelengths of blue light are also in sunlight. White light is high-intensity and may over-stimulate the eye’s photoreceptors, making it more difficult for melanopsin to respond. The application of a blue light in light therapy products has a more positive effect according to Dr Norman E. Rosenthal’s reference research on light therapy. Blue light can provide a quicker treatment for SAD and it has no reported side-effects. It has recently been discovered that the specific wavelengths of blue light that are also in sunlight, promote a more positive response in light deficient patients than traditional light boxes that use white light.
Blue light can be also found in other devices such as computer screens, mobile phones, e-books and other digital devices. However this shorter wavelength of a blue light contributes to digital eye strain and this could lead to serious health problems. A recent research project by the Harvard Medical School has found that exposure to blue light decreases the production of melatonin more than any other type of light and having too much blue light can cause problems in our circadian rhythm which can have devastating health effects.