Monthly Archives: May 2016

The future of colour is quantum


Although our digital displays can show literally millions of colours in fact they show us less than half of the possible colours in the world. This is partly because of the reliance on trichromatic devices – what you probably know as RGB. No matter how we choose them, it is impossible to mix together three colours and make all of the other colours. This is despite this embarrassing statement on the BBC website:

Red, yellow and blue are primary colours, which means they can’t be mixed using any other colours. In theory, all other colours can be mixed from these three colours.

This is just plain wrong. It is not the case that in theory, all other colours can be mixed from these three colours. In theory, and in practice, they cannot.

But I digress. The point is that using a three-colour primary system – a trichromatic system – is never going be able to reproduce all of the possible colours in the world. But even if we do use three, we could do better than the current TVs, phones and tablets on the market if we could improve our technology. The problem is that the red, green and blue lights in these displays are not as bright and colourful as they could be. That is where quantum dots come in.

Quantum dots are tiny crystals that can be precisely tuned to efficiently produce very specific colours. The crystals are grown from a mixture of various semiconductor materials and liquid solvents. By carefully controlling the conditions, engineers can adjust the size of the crystals, which determines the wavelength of the light that the crystals emit. Smaller quantum dots, with a diameter of two nanometres (two billionths of a metre) or so, emit short-wavelength, or blue, light. Bigger dots, with diameters closer to eight nanometres, produce light that’s nearer the long-wavelength, or red, end of the spectrum. We can expect to see new technology on the market soon offering brighter and more colourful displays.

Colour: Art and Science


I run a module at the University of Leeds called Colour: Art and Science. For me colour is a classic meta-discipline and understanding of colour requires and appreciation of ideas from lots of different academic fields. So I like to present a very multi-disciplinary perspective of colour and I have students enrol from all sorts of different departments in the University which is a lot of fun. One of the main reasons I run this blog is as a resource for those students.

So I was interested to just come across this Brief History of Colour in Art by Sarah Gottesman which covers some of the same stuff that I talk about.

In the same vein I came across this discussion by @CINEMAPALETTES about cinema colour palettes that shows how colours are used to set the mood of iconic films.

The redder the male, the more successful it is.


According to Joseph Corbo, an associate professor of pathology and immunology at Washington University, the genes affecting red coloration belong to a wider family of genes involved in detoxification. Redness may be a sign of a robust, quality mate who can easily cleanse harmful substances from his body.

“In many bird species, the redder the male, the more successful it is at finding mates,” – Joseph Corbo.

For more see

green light may cure your headache

I get migraines. Not often. Just a few times each year. But when I get one I have been known to turn off the lights and go to sleep in my office. I have found that taking a pain killer and then going to sleep is the only way to relieve my symptoms. But a study in the journal Brain suggests that exposure to green light actually has a beneficial effect.


In the study 80 percent of subjects reported intensification of headache with exposure to high intensity of light, except green. Surprisingly, the researchers found that exposure to green light reduced pain 20 percent. They also found that the signals generated in the retina for green light are smaller than those signals generated for red and blue light. Researchers are now trying to develop a more affordable light bulb that emits pure narrow-band wavelength of green light and sunglasses that can block out all colours of light except narrow-band green light.

non-visual effects of light

Most people know that the ear system has two functions: hearing and balance. It is less well known that the visual system also has two functions. The first is seeing. The second is a set of non-visual functions including circadian rhythm. Mechanisms are being discovered that are particularly sensitive to blue light. So short-wavelength, or blue, light inhibits melatonin which is a chemical that makes you drowsy. So looking at bright lights late at night, especially blue ones, can contribute to a poor night’s sleep. So put your smart tablet away now and go to sleep!

In all seriousness though, I knew there was a reason why I do not like watching Chelsea on Match of the Day.


Studying these functional effects of colour and how they can be used in design is a major theme of the research I lead at the University of Leeds in the School of Design. If you have interest in these areas please contact me.

clothes that change colour

Colour-shifting threads that change their hues in response to electrical charges are being developed as part of Google’s Project Jacquard. The technology still has a way to go before it could be in the shops but it gives the potential that your could change the colour of your clothes with the ‘flick of a switch’ rather than buying new ones or even that clothes could change colour with your mood. As if that would be a good thing.

For more see here.

Looking for colour blind people

colour blind example

Most colour blindness is hereditary. The faulty ‘gene’ for colour blindness is found only on the X chromosome. You have two X chromosomes if you are female or an X and a Y chromosome if you are male. It is because females have two copies of the X chromosome that they are far less likely to be colour blind. A male inherits his X chromosome from his mother and his Y chromosome from his father. So men do not inherit colour blindness from their fathers but from their mothers who can be carriers if they have one faulty X chromosome. Snoooooooooze. Probably you are bored reading this. The real point of this post is to say that Bradford University in the UK are studying colour blindness and are seeking females who are not colour blind but who have a child or a sibling who is. If this sounds like you please get involved in the study, help someone get their PhD, and maybe find out something interesting and useful. For more details see here.