Single person experiments with light

A romantic dinner by candle light, bright lights in an office building. Both give us a very different experience. We all know from experience how light can influence our mood and the way we perceive a space.
What I want to find out with Meditation Lab is if light conditions can also influence the quality of your meditation experience. I have a hunch that it does. This is also based on over 20 years of daily meditation practice. And I’ve found starting points on optimal lighting during meditation in scientific research.

Building a meditation lab in my attic

Building a meditation lab in my attic

Conditions for a good meditation session

Contrary to a commonly held belief meditation isn’t about being relaxed and a little sleepy. I practice in the Buddhist tradition of Vipassana (insight) meditation. This form of meditation is about being fully present in the moment without effort. This clear observation will give a person insight into the true nature of reality. This insight will help to overcome suffering and to become a wiser and more compassionate being. An important concept in this context is the Satipatthana.
So the ideal state for a good meditation session is being relaxed but at the same time alert. I had heard about changing light conditions in classrooms to support different activities and states of mind of students. I was also wondering if work had been done on the psychological aspects of light. I’ll summarize my findings and tell about how I will be translating that into one person experiments.

Working with a light expert

Before diving into the theory I would like to explain how I will go about changing the light conditions. I was very fortunate be introduced to Tom Bergman. He is Principal Scientist at Philips Lighting. He has been working on what he calls Light instruments: LED light systems that can be programmed and played like a musical instrument. With his instruments he wants to go beyond mere functionality and use light for expression and experience. Our goals and explorations were a perfect match. I will be using his 9 x 9 mosaic instrument. It can make all colours and make beautiful and unexpected colour transitions. Also interesting is that it has been tested as tool for relaxation by master student Nina Oosterhaven (1). Her study showed for example that looking at changing patterns of light showed a significant reduction in heart-rate. So there are interesting starting points to work with the instrument.
The light instruments are of course very specialized and not commercially available. So Tom kindly also supplied me with a Philips Hue Go. This will enable me to try out similar settings with a consumer device which is already Internet of Things ready.

The lab set up: Light instrument, meditation mat and data server

The lab set up: Light instrument, meditation mat and data server

Types of light

Psychological effects

In the various articles I read I was looking for settings in light colour and intensity that would either relax or activate people and make them alert. There hasn’t been much research on the psychological effects of lighting. Seuntiens and Vogels(2) have done research on atmosphere and light characteristic in living room settings with a group of light designers. They looked at four types of atmospheres of which activating and relaxing are relevant for Meditation Lab. Interesting were their findings on the influence of colour temperature, brightness and dynamics on these atmospheres. In general the findings were: warmer (+/- 2700 Kelvin), static and less bright light (180 lux) is perceived as relaxing. Cooler (+/- 3800 K) and brighter light (390 lux) is perceived as activating this light can have a slow dynamic.

School performance

Sleegers et al (3) looked at school performance in children and students under adjusted light conditions. Their studies used build in light systems which had different settings. Focus, calm and engery are the most interesting for my project. Energy is an interesting setting, it is used in the morning or after mealtime to overcome sluggishness. The settings correspond with the following light properties (measured at eye-hight):
Energy:650 lux and 12000 K colour temperature
Focus:1000 lux and 6500 K colour temperature
Calm:300 lux and 2900K

Staying awake

Jacques Taillard et al (4) studied the effects of blue light on staying awake whilst driving a car at night. They compared the effects of continuous blue light to drinking coffee. When compared to a placebo both coffee and the blue light condition reported significantly less inappropriate line crossings with coffee doing only slightly better then blue light. The light source was a Philips GOLite with a wavelength of 468 nm. Luminance level was around 20 lux measured at eye level.

Research design

Sleepiness, tension and lack of focus are challenges you face when meditating. By experimenting with different types of light I want to find out if the findings in other areas can be used in a meditation setting. I will use warm white light for relaxation, cool white light for focus and blue light for alertness. I will be exposed to one light condition per 20 minute meditation session. Before and after every session I fill in the standardised questionnaires which I have designed. I have started single person experiments (n=1) and I have designed the following experiments.

Design single person experiments

Design single person experiments

There is no baseline measurement included in the single person meditation session. Instead I have conducted 54 baseline session under my usual meditation conditions. I did a 6 day solitary retreat at home. The sessions took place throughout the day, I didn’t manipulate anything, especially not the light conditions. So they varied widely as the day progressed.

Current findings

At the moment I’m conducting n=1 experiments using the Light instrument and the three main light states described above. I’ve set up a darkened lab to control the light conditions. I keep my eyes slightly open with my gaze turned down.
My first impressions are that there is a difference from what I normally experience during meditation. The white lights I find quite relaxing and somehow invigorating. The blue light I find less pleasant and a bit depressing. I suppose the light will interact with my overall state of focus, sleepiness and alertness as it fluctuates during the day. That is why I try to do the experiments at different times of the day while using the same light setting. I do worry a bit about my sleep when meditating in the evening in bright light. For that reason I have turned down the brightness (there a 5 settings) in an effort to not affect my sleep too much.

The single person experiments are my starting point. Later I will report on my design for group experiments. I’m always on the lookout for people who would like to join the experiments. So please leave a comment if you want to participate.

1) Oosterhaven, N. (2017). Fascinated by Dynamic Lighting. Thesis Master of Science In Human Technology Interaction
2) Seuntiens, P.J.H. & Vogels, Ingrid. (2008). Atmosphere creation: The relation between atmosphere and light characteristics. Proceedings from the 6th Conference on Design and Emotion 2008.PJC Sleegers, PhD, NM Moolenaar, PhD, M Galetzka, PhD, A Pruyn, PhD, BE 3) Sarroukh, PhD, B van der Zande, PhD (2013). Lighting affects students’ concentration positively: Findings from three Dutch studies. Lighting Research & Technology Vol 45, Issue 2, pp. 159 – 175
4) Taillard J, Capelli A, Sagaspe P, Anund A, Akerstedt T, Philip P (2012) In-Car Nocturnal Blue Light Exposure Improves Motorway Driving: A Randomized Controlled Trial. PLoS ONE 7(10): e46750.

Neck sensor does his work

Last week we made great steps developing the sensors and the electronics.

We chose another sensor for in the neck. It detects movement to the extent we want it. We found a solution to include the sensor in the Silence Suit. We went further with the experiments we did last week. We chose another cloth for the turtleneck which is more flexible. It sits tight enough at the neck that the sensor can detect every move you make. Although there are still some small disturbances, three different angles can be detected very well. We can determine movement forward, to the right as well as to the left.

neck sensor - detecting every move you make

neck sensor – detecting every move you make

To make it more comfortable we cut it out at the front. So, the turtleneck will not influence your breathing. It is still sketchy but we are very happy we found a way that it works. Now it is up to our designer to optimize the look.

turtleneck - cut out at the front

turtleneck – cut out at the front

We have found a new sensor detecting the pressure between your fingers. We want detect light pressure. It is more sensitive than the one we used before. The amount of pressure between your fingers during meditation is a good indicator of your concentration level.

We changed the microcontroller we want to use. We included a battery so you can recharge it easily by connecting the microcontroller to your computer.

German has introduced us to a convenient platform to communicate with each other. We share our progress questions and discoveries among ourselves using Dropbox Paper. We are really happy that we can work together on one vision by sharing our thoughts that easily.

Dropbox Paper

Dropbox Paper

Danielle’s research about the influence of the light is difficult because there is not that much investigated about it. We are waiting for the thesis of an intern from Philips Research who has focused on the influence of light on relaxation. The experiments Danielle wants to do with the sketch of the Silence Suit cannot be thought out because she misses some academical input. So, if you maybe know some interesting literature about the influence of light either on psychological or on scientific level, please let us know by leaving a comment.

Today I picked up how important it is to go on. No matter how small the steps seem that you make, they are all crucial to reach your goal. As you can see, we are making crucial steps to realize the Meditation Lab Experimenter Kit. And we can enjoy every small success we have, for instance the solution of the neck sensor today. But there is still much to do. I am excited what comes next.

Relief! The organisational problems reduce

Last week, I was busy with sewing the sketch of the Silence Suit. But I also was busy with the project in my head. I really was wondering how Danielle’s week would pass. Last time she seemed stressed and exhausted because of many organisational problems. So before I came this time I really hoped that many problems would have been solved. I was excited if the wearable would fit and if we could start looking for the sensors and the wiring.

So the question in the beginning “How are you? And how was your week?” had an extra meaning today. She seemed relieved: “I could eliminate many stress factors”, she says. That means she knows every team member can meet the milestones. Moreover, she does not have to solve the organisational problems all on her own anymore, but her mentor will take them on.

Because she didn’t have to focus on these things anymore, Danielle could concentrate on the corporation with Design Lab. Students from the University of Twente will work on the design, the developing and the production of the PCB’s for the microcontroller. Furthermore, they will optimise the suit and the cabling, as well as the interaction with the suit.

“So this is all very good news. But my highlight was the visit of Tom Bergman from Philips Research.” Last Friday he came to show the opportunities to influence the sphere of the environment by light. Danielle could try if the light has some influence on her mood by putting on the wearable. She could see that intensity and colour of the light can be detected by the sensors of the suit by sitting in front of the apparatus of Philips. The experiment was successful and we know that the apparatus is strong enough to influence the environment.

testing the influence of light - with Tom Bergman from Philips

testing the influence of light – with Tom Bergman from Philips

It is a well known phenomenon that you can recharge your energy by experiencing nature. It is called restoration and Danielle already worked with it in one of her projects Virtual View. But is seems that this phenomenon also works with light. Maybe light could work as influence as well as expression of the quality of the meditation session.

Besides that, we want to focus on the sensors and the cabling today. The sensor in the neck that detects movement has to be optimised. We make a first try by just sticking the sensor on the neck. We want to try where the sensor has to sit, so it detects the movement the best. We validate what Danielle already expected: The sensor has to sit as high as possible on your neck.

neck sensor - logging different positions

neck sensor – logging different positions

Moreover, we have to work on the sketch of the wearable I made. Because the sensor has to be included in the neck of the wearable. On the one hand, the sensor has to sit that tight that it detects every movement, but on the other hand it still has to sit comfortable. We try different options. We choose a turtleneck with some Velcro at the front to open, close and tighten the suit. But that is not enough. Also the other option we tried with some elastic does not work. It is still too slack and the sensor does not move enough to detect. So next week we have to look for another option. We already have some idea’s in our hearts but maybe you know a solution for our issue. So how would you solve that problem? Let us know by leaving a comment.

turtleneck - trying to include the neck sensor in the sketch of the vest

turtleneck – trying to include the neck sensor in the sketch of the vest

So you see by outsourcing tasks which stress you, you can focus on the things you like the most. It was really nice to see Danielle that happy and relieved today. I learned for myself how worthwhile it an be to ask one another for help. You see the value of a team. Maybe the things you are struggling with are for others much less complicated.



library atmosphere

The past couple of weeks I’ve been working on an assignment for the municipal library. The task was to let people present their views on the library of the future. To that end we created an area with seats, a bar, a touch table and lights. By touching a picture on the screen visitors could select a different atmosphere and actually change that by at the same time changing the colour of the lights. The choices of the visitors were logged in a file. This installation was presented during the Cultuurnacht (culture night) in the city of Breda, the Netherlands.

My task was to make the interactive application and drive the lights. I’ve wanted to experiment with interactive lighting so I can apply it in my Hermitage 3.0 project. So for me it was a great opportunity to learn about it. And learn I did.

My idea was to work with the Philips Hue. They have a great API and an active community. But due to budgetary restrictions I had to work with an alternative: Applamp, also known as Milight. The concept is the same: a wifi connected bulb can change colour and brightness by sending code to a local server port generated by a small wifi box. Applamp also has a phone app to work with the lights and a very basic API.

I had wanted to start working on the application before Christmas but this ideal scenario didn’t work out. The bulbs arrived mid January… The first task was to connect to the lights using the app. It appeared that my Android phone was too old for the app to work. So I had to borrow my neighbours’ iPad. The bulbs can be programmed into groups but you have to follow the steps in communicating with the lights otherwise it won’t work.

Applamp with iPad app

Once the bulbs were programmed I thought it would be easy to set up a simple program switching a bulb on and off. I’d found a nice Python API and some other examples in different languages. Non in Java or Processing though. I’ve used Processing because I wanted a nice interface with pictures, a full screen presentation and log the actions to a file.

I tried and tried but the UDP socket connection wasn’t working. So the biggest thing I learned was to do with network. I received a lot of help from Ludwik Trammer (Python API) and Stephan from the Processing forum. The latter finally managed to retrieve my local IP address and the port for the Milight wifi box, which was all I needed. (You actually don’t need the precise port, sending it to .255 is good enough.) The light technician Jan showed me a little app called Fing that makes it super easy to get insight into all the things connected to your local IP.

In Processing I wrote the interaction making sure that no buttons could be pressed while the program was driving the bulbs. There should be at least 100 ms between the different commands you send to the bulbs. This made the program a bit sluggish. But if the commands are send to quickly it doesn’t reach the bulbs and the colour doesn’t change. I had to fiddle around with it to get it stable. But the settings in my home weren’t optimal for the library. Alas there was not enough time to experiment with it there. So it wasn’t perfect but people got the idea.

This is a snippet of the program in Processing:

// import UDP library

UDP udp;  // the UDP object
int port = 8899; // new port number
String ip = "xx.xx.xx.255"; // local ip address

int[] colourArray = {110, -43, -95, 250, 145};
int currentAtmosphere = -1;

void setup(){
  udp = new UDP(this, port);
  startState = true;

void mouseClicked(){
  currentAtmosphere = 1;
  RGBWSetColor(byte(colourArray[currentAtmosphere]), false);

void RGBWGroup1AllOn(){
  udp.send(new byte[] {0x45, 0x0, 0x55}, ip, port);

void RGBWSetColorToWhiteGroup1(){
  RGBWGroup1AllOn(); // group on
  udp.send(new byte[] {byte(197), 0, 85}, ip, port); // make white
  udp.send(new byte[] {78, 100, 85}, ip, port); // dim light

void RGBWSetColor(byte hue, boolean tryEnd){
  udp.send(new byte[] {0x40, hue, 0x55}, ip, port); // send hue
    udp.send(new byte[] {78, 100, 85}, ip, port); // dim light
    udp.send(new byte[] {78, 59, 85}, ip, port); // full brightness

Another thing that’s puzzling is the hue value that has to be send. As all the codes send to the bulbs should be in byte size the hue must be a value between 0 and 255. The hue scale of course is from 0 to 360 degrees. I’ve figured out how they are mapped but found out by just trying all the values from 0 to 255.

I’m happy to say that the installation was a success. People thought it was fun to work with it and I had some nice insights into peoples idea’s for the library of the future. The final presentation could have been more subtle. But that’s something for next time.


analogue input

Today I did a little test using analogue input for my LED. I build my third RBBB today and wanted to take the LED output a little further. For my breathing device it will have to respond to the analogue input of breathing. So I emulated that with a light sensor. Covering the sensor less or more changed the brightness of the LED. For a start it was fine, but with breathing the LED will have to go from no light to very much light to give proper feedback on the respiration pattern.