Observations about the universe, life, Lausanne and me

Saturday, December 27, 2008

Lightbox Construction

Yet another update (01/16/2009): It worked! My sister reports feeling much better.

Update: For more facts & numbers, see my follow-up post here!

My sister suffers from seasonal affective disorder, also known as winter depression. A commonly prescribed therapy is light therapy - about thirty minutes of bright light in the morning. Bright in this context means more than 10 000 Lumens. You can of course buy commercial light-boxes, but I wanted to construct one by myself...


Behold, the DIY receipe for your very own Lightbox!


You will need:


  • A load of  light-bulbs - I used ten 23 Watt flourescent bulbs which were advertised as the equivalent of 130 Watt incandescent bulbs. Anyway, we are interested at the amount of light they put out: 1560 lumens each. The light colour does not seem to be very important, according to the literature dealing with S.A.D. - just avoid daylight bulbs that emit UV.

  • A box - I used a cheap Ikea Mackis plywood box. It's height fits the bulbs I choose perfectly, and you can get up to twelve of them into it. Above to the right you can see where I tried to figure out the placement of the bulbs.
     
  • Bulb holders and cable and a plug - the cheapest ones, the holders won't get very hot.
     
  • Some way to drill the holes for the bulb holders into the plywood. I used a drill that is meant for use with floortiles. Not perfect, but it worked.

After you have figured out the placement for the bulbs, drill the holes into the bottom of your box. It is not necessary for them to be very neat, since they won't be visible afterwards.



Then find a way of making the interior of the box reflective - if you are cheap and lazy like I am, a bit of aluminium foil will do. If you are awesome, you could drill holes in mirrors or something.



Next on: fitting of the bulb holders and cabling. Use some non-shrinking adhesive to secure the holders - I used "Konstruktionskleber", you could use silicone as well, I guess, or some epoxy. Then you want to connect all of those bulbs in parallel.



Here cabling is finished, and the first test has commenced. After thirty minutes the air inside the box was warmish, but in no danger of overheating and melting the bulb-holders or setting fire to the wood.



When the box is operational, and you have checked your cabling for short-circuits waiting to happen (exposed leads and so on) , it is time for cosmetics, i.e. hiding all the cables from the casual eye (and from not so casual toddler-hands).

Simply glue the top of the Ikea box on the back - if you have measured and planned carefully, all those cables should have place beneath it. If you haven't, it is time to curse and get out something you can use as spacer. I was lucky, though: everything fit.



And here it is, in all it's glory:



Yes, it is bright. Flee, oh demons of depression! Flee the holy light!

48 comments:

DU said...

And now the $64k question: Does it work?

I've thought of building one of these myself, but I've been unwilling to go to the trouble and expense only to find no effect.

Irregular Shed said...

This looks great. I might have to give it a go - the cost savings are immense. Maybe slide in a very pale blue gel in front of a few bulbs to make it a little more "daylight" and the addition of a PC case fan just to keep things happy.

James Stoffel said...

I, too, am curious as to whether it is helping your sister. Can you give any comments/results?

Thank you for posting this instructable.

Anonymous said...

I have one of these (or similar) that is used to provide vegative lighting conditions to plants. it utilizes up to 10 sockets, but lacks the [up to code] touches of yours

Anonymous said...

It's worth pointing out that recent reports suggest energy saving light bulbs can be dangerous if used too close to the skin, due to the UV light emitted. Try a search on google for more info, but here is an example from the (UK) Independent newspaper:

http://www.independent.co.uk/life-style/health-and-wellbeing/health-news/energy-saving-light-bulbs-can-emit-enough-uv-radiation-to-damage-skin-956696.html

Perhaps regular incandescent bulbs would be wiser, in spite of the heat and energy issues...

Anonymous said...

Sheet of uv filtering transparent material in front of bulbs ?
The cooling necessary with so many strong incandescent bulbs would be a bigger pain in the arse to set up than finding a filter.

Anonymous said...

While this is valid, I found it easier to use a commercial fixture about the same size that's meant to fit in a suspended ceiling in an office. Costs $30 or $40, I think. I took off the filter it came with and added a piece of polycarbonate (NOT plexiglass) sheeting I got at a lumber place to filter the UV. I sanded it to make it disperse and soften the light more. With the commercial product, no need for a fan. If you need a fan for the version you're making, look at someplace like allelectronics.com, goldmine-elec.com, or sciplus.com for an inexpensive electronics cooling fan. You probably don't need a very big one, and if you put some large holes in the box, and kept it upright, you probably wouldn't even need that.

Unfortunately, I found that my lightbox sensitized my eyes anyway, so I gave it up. It took a few weeks to do that, so maybe just a bit more work would fix the problem.

I've had the same problem with a commercial unit.

Anonymous said...

I have SAD and I have found that massive doses of vitamin B12 helps out wonders. 2000mcg a day+

Boris Legradic said...

Hey all, thanks for your nice comments! Unfortunately I can't tell you if it works yet, since it can take up to two weeks for the light therapy to start and show an effect. I'll update when I know more.

The colour of the light is actually not that important (humans are not plants), you just have to avoid UV light, or else you might give yourself skin cancer to replace your depression - or at least develop a weird tan in your face.



@ Irregular Shed: I actually considered having some kind of diffusor in front, but in the end decided against it. For one, it would mean a drop in luminance, and the box is meant as a medical device and not as a pretty lamp. furthermore, with an open box a I don't have a problem with heat build-up, so no need for fans.

@Anonymous:
Cheers for the heads-up re: UV-light, I'll check it out, maybe at a thin sheet to screen it out.

Anonymous said...

Worrying about the UV emitted is mostly pointless. As the below article states, much less UV comes from these bulbs than the sun, and even some incandescent bulbs. Of course if you are truly that worried, get a sheet of UV blocking plastic.

http://energystar.custhelp.com/cgi-bin/energystar.cfg/php/enduser/std_adp.php?p_faqid=3867

Michiel Vleugel said...

Not sure if this actually works - the commercial lightboxes use full-spectrum light and operate at high frequentcy (10k+).

Anonymous said...

I'm not sure, but didn't those light, that's suppoused to help for kaamosmasennus, can't remember it in English right now, have sertain lightcolour? In kelvins? Like plantlights?

Mmm, plantlights for humans.. :)

Or is it flower bulbs?

Happy new year!

Sonja from Finland

Jessica T. said...

That's pretty cool! I am also curious as to whether it works. I always thought light boxes had special bulbs.

Anonymous said...

The light box has to be full spectrum, which means fluorescent is not good. As for UV it can actually cause eye damage. Don't take my word for it. Ask someone like a professional. Even blue light can cause eye damage, that's why it is not used in this application any more, to my knowledge. Sorry to dissapoint you, but I'm sure you dont want to damage someone's eyesight.

Mark said...

The important number in a phototherapy unit is "lux," not "lumens." Lux is measured at the surface being illuminated, so it's critically important to know *at what distance* the unit delivers the 10,000 lux. Amounts in excess of that are quite likely to cause side effects, so get a light meter and measure! Moving the box away will very rapidly reduce the light intensity. Lumens, by contrast, measure how much light the unit puts out. This is of no importance if the box is 20 feet away. That's why lux is used.

"Full spectrum" is not at all needed or even useful. Many different wavelengths work. Commonly, commercial units use bluish LED's. As for UV, the concern isn't a tan or even skin cancer: it's blindness.

These units DO NOT WORK when used ambiently. The patient needs to set it up so that 10,000 lux hits the glabella (between the eyes) then LOOK DIRECTLY AT THE UNIT for 20 to 30 minutes.

Mark said...

Oh, all currently-available commercial phototherapy units that do no use LED's *are* fluorescent, so just ignore the comment above my first one. As for asking a professional, I am a board-certified psychiatrist with experience in treating seasonal depression.

Kev said...

Interesting. Might have to try this for my wife - she tans some winters to help with SAD. (I think I might be developing it too).

Last time we investigated lighting to help - the literature said to use the natural light light bulbs that *do* put out UV... I guess that's changed then?

Anonymous said...

Great idea. I may try it myself. I've done some research into reflectivity and it would be more effective to paint the inside of the box with a flat white paint. It will provide a more consistant reflective surface. If you want to spend money, Mylar is also an option, but you have to be careful to install it without any wrinkles. If you want to use aluminum foil, use then non-shiny side. But, in the end, flat white paint is the best and least expensive option.

DU said...

I have yet to see any efficacy claims, let alone proof, even from the "board-certified professional".

Also: Glass blocks UV, so almost any bulb is going to be pretty safe. Doubly so if you put a glass shield on the front. (Tanning booth bulbs are encased in quartz rather than glass, IIRC.)

Ivan said...

Not every bulb is effective for SAD. You must use a "blue" bulb, with a color temperature of 6000 or 6500 Kelvin. The "usual" bulbs are 2700 or 3000. Thankfully, your favorite Orange and Blue home improvement stores routinely stock these now, at reasonable prices... I have had positive results from merely using 2 23W bulbs in a regular two-bulb lamp fixture, for an intermittent and mild recurring case of SAD; I don't have to stare at the light, I just turn it on over my head while reading the morning web news, and ambient is sufficient.

demento.fan@gmail.com said...

Years ago I saw a program that presented someone who invented a visor with small lights that he claimed would reset his internal clock and eliminate jet lag, as opposed to the artifically lit full environments NASA uses to reschedule astronauts' internal clocks before they travel to the ISS. The advantage of a visor is that you can deliver just as much light to the eyes and the surrounding area with only a few very small bulbs like Christmas lights. I wonder if this actually did work for jet lag, and I wonder if it would work for SAD.

FakyMcFakerson said...

@DU Glass doesn't block UV. Certain types of treated glass do, but not all glass.

Schwern said...

Before we all get our panties in a bunch over UV, let's read the article...

The research showed that one in five of the "open" bulbs emitted UV light equivalent to that experienced on "a sunny day in summer" when in very close proximity (less than one inch) to the skin, which warranted "some precaution". When the light was moved further away, beyond one foot, the UV level was below the exposure on a sunny day in winter and was "not a concern".

[Justin McCracken, chief executive of the Health Protection Agency] dismissed suggestions that close exposure to the UV light emitted by the bulbs could cause cancer. "That is not what we are saying. At the exposure levels that we are talking about, the worst is that you could have short-term reddening of the skin. We do not believe these lights pose any risk in terms of skin cancer." However, people with light-sensitive conditions "need to be careful", he added.

So unless you are A) particularly sensitive to UV and B) plan on shoving your face up against the lightbox, you're fine.

DrM said...

There is no doubt that light boxes have an effect on SAD... certain wavelengths of light are transmitted through your retina affecting various nuclei of your brain, resulting in a cascade effect that affects hormones and neurotransmitters. However, there has been some interesting literature published recently that seems to propose a deficiency in vitamin D3 also contributes to SAD (D3 receptors found in many organs, including the brain). Those of us living above the 41st latitude are at increased risk for both SAD and Vit D3 deficiency due to the decreased light intensity/daylight hours. Just food for thought, but a cheap lightbox and $8.00 for a bottle of D3 (2000 - 5000 IU/day - not to exceed 10000 IU/day) might just do the trick.

Anonymous said...

It's best to use the dull side of aluminium foil. Reflects light better...

Justin said...

How much did this cost? Please post an itemized price for this project

Lord No Trousers the Versace said...

Farken heck... and my father just bought one of these (yes, $200+) for christmas.

I've been using it for about 2 weeks and I find more than anything it really just helps keep me awake. Its also a great way to make a room with little natural light really light up. I leave mine on quite a bit even when I'm not sitting right in front of it.

Oh and in response to another poster who said you HAVE to sit right in front of it, my light literature says otherwise. At 2-3 feet you get 10000 lux. Under 6 feet its something like 8000 and if you use it more as ambient goes down to 5000 or 6000.

According to the instructions, a lower lux means that you have to spend more time around the light to see the effects. It recommends 2-3 hours if you're under 6k lux whereas the 10k is only 20 minutes.

It was also recommended that the light be in front of you and at a downward angle to get the full effect.

Light is highly correlated with melatonin production. I think mine is having a really positive affect on helping me get out of a daze in the morning. On rainy days its a miracle to "see the light"

Somehow I am doubtful of a DIY job. If it is just as effective this is a great instructable!

Boris Legradic said...

Hi all, thanks for all the comments! I have a long follow-up post here , where I address most of the issues that have come up, and also provide some references to the relevant literature.

Tom said...

If there's anyone considering building one of these who isn't a qualified electrician, I have one work of advice: DONT.

'Connect 12 bulbs in parallel'... so what is the current drain on that, then?? More than your flimsy looking cables and connectors are rated for? You betcha... Massive fire hazard!

Also, glueing electical fittings in with silicone or epoxy is a pretty bad idea, what with many silicone sealants and epoxy resins being flammable.

Tom said...

Maybe I should have mentioned in my above statement that I am qualified in all that... (Masters Degree in Engineering from University of Cambridge, plus an apprenticeship in general engineering)

Boris Legradic said...

@Tom:

Ohh, I'm so impressed with your qualifications!
Only, if you are such a badass electrician, you should be able to figure out the current draw easily, as I did: ten times 23 watt CLFs is 230 Watts of power, or about 1 ampere at 220 volts AC.

ONE ampere! Scary, huh? I hope the flimsy standard cable will be able to take that. Oh wait, they are rated to do 6 amps.

As for the flame hazard - the glue I used is not flammable. Furthermore, CLFs don't get very hot, as a matter of fact, the ones I used you can even touch while in operation, which means below 70 degrees celsius.

The conclusion: The best qualifications in the world don't help you if you don't think before you write .

scout said...

I use a sadelite (http://www.northernlighttechnologies.com/products_sadelite.php) in the winter months here in the northeast US with tremendous success. One key for me has been using it *regularly*... every morning for at least 30 minutes.

Your home-crafted solution (clearly enabled by significant practical experience with wiring electrical systems) looks like a great economical alternative to my "happy light"; I hope your sister has the same kind of success that I have!

Boris Legradic said...

Thanks scout, actually she did, see here .

Although you really don't need elite wiring skillz to do this - if you know how to wire up a lightbulb, then you can build this too. Although you don't save that much money over a commercial version, so there is not much sense in building it yourself - except for the fun of it!

Liyang HU said...

Just a few short notes for any UK readers:

I couldn't find Edison screw bulb holders (ES/E27) in the UK like the ones you used, so I ended up buying a bunch of ceramic holders (with mounting holes at the bottom) off eBay. £20. Ouch. (They were advertised as reptile aquarium / ‘hydroponics’ lamp holders.) You don't want to use bayonette holders as the bulbs will wobble.

The bulbs themselves (spiral, 120W) were £35 total, from UltimaStore.co.uk. Ikea seems to be out of stock of the Mackis storage boxes all over the UK, but with a bit of ingenuity (and lots of sawing; remember to drill pilot holes in the plywood or it will split. Get the Mackis if you can.) you can equally use the Fira CD/DVD drawers.

Plug and wire I had lying about; in-line switches and terminal blocks are dirt cheap from Wilkinsons. Add a timer if you wish.

Finally, a note on safety: make sure the wire is secured to the box. Use a thick piece of plastic to clamp the end of the wire to the box, like you'd find in a mains plug. You really wouldn't want a live wire dangling about if you accidentally tug on it.

Anyone who paid attention in secondary-school physics shouldn't have problems wiring this up. (Admittedly, most people didn't.)

Boris Legradic said...

@Liyang HU:

I am very happy that you found my post useful - and that you stopped by to tell me about it! I do hope the lightbox will help you as much as it helped my sister.

Thanks also for the UK construction details! I bolted the wire down with one of those metal-clamp thingies, but forgot to mention that in the blogpost.

Cheers,
Boris

Heide said...

You should submit that idea to http://ikeahacker.blogspot.com/

Anonymous said...

@ tom "The conclusion: The best qualifications in the world don't help you if you don't think before you write" - that's gotta hurt!

@ boris. Excellent little project. I shall make one.

Ashley said...

less spite, more science.

for everybody's benifit here is the correct way to calculate the current this circuit draws:

the resistivity of a 23W light globe running on 220V is:
R = V^2 / P = 220^2 / 23 = 2100 Ohms

Then for a circuit in parallel current may be calculated as:
I = V * (1/R(1) + 1/R(2) + ...) = 220 * 10 * (1/2100) = 1.04 A

For comparison's sake, if the circuit was wired in series the current drawn would be:
I = V / R(total) = 220 / (10 * 2100) = 0.01 A

So you can see that the point that Tom was trying to make about the increased current drawn by the circuit due to it being wired in parallel. However most wall outlets are wires to 10+ amperes so this is not a dangerous load.

However, "ONE amp" [your caps] actually IS a lot of power. Just cos the number doesn't have a lot of zeros after it doesn't mean it won't give you a very serious shock!!

Was there a reason you chose to wire it in parallel? I can see that it may be more convinient when a bulb blows - just the faulty bulb will be down, not the whole circuit - but I'm not sure whether this warrants a hundred-fold increase in the amount of current your device draws?

This article may be of help:
http://en.wikipedia.org/wiki/Series_and_parallel_circuits

Ashely said...

*benefit

Boris Legradic said...

@Ashley: And where do you think the power would come from? If you lower the current, you have to increase the voltage. Since the mains provide a constant AC voltage source, you can't use a series circuit - it would act as a voltage divider (assuming CFL's still act mainly as resistances and not reactances which I think they do), and each CFL would only "see" 24 Volts, so they wouldn't light at all.

By the way, you can't use Ohm's law to calculate the resistance of an AC circuit, what you are calculating here is the magnitude of the impedance, not the same thing at all.

Furthermore, while 1 Amp is more than a lot in some circumstances (more than ten times the current necessary to kill somebody, if it were to go straight through the heart), it is not a lot when using proper cables and connectors. Your PC draws more than one Amp, if you have an electrical heater it will draw anything from one to five amps.

While appreciate it when people try to warn others of dangers when handling electricity (and don't do it in a snooty tone, right Tom?), please make sure you have got your facts straight. You don't do anybody a service spouting of half-truths.

JC said...

Hey Ashley: oh my, so much fuss over some electrical calculations. One Amp of current actually does not define power at all. Power is in fact rate of energy conversion. To work that out you typically need to know both potential difference (Voltage) and rate of electron flow (Current). As for how dangerous it is! Well electric shock is best defined by energy (Joule) which is the product of Voltage(V) Current(I) and time (s). Of course another important factor in severity of electric shock is the path of the energy (eg hand to hand). By the way, if you put yourself in parallel with the light box (electrically speaking - and not recommended) you will not draw anywhere near one Amp, and you will not affect the one Amp (approx)current drawn by the light box in any way, it will still work happily along with you in parallel (you won't be so happy) . Typical body impedance is in the order of kilo Ohms at these voltages, and you will typically draw a current in the order of milli amps. Finally, great light box design Boris.

Jay said...

It gives me a warm and fuzzy feeling when you pwn the besserwissers Boris :)

Boris Legradic said...

I aim to please, Jay, I aim to please ;)

The Cruel Regulator said...

hi, i know that this is a treatment of SAD but i get a very little amount of sleep everyday, i live on the eastern coast of australia so i don think SAD could really effect me that much.
i have depression and anxioety and this coupled with school stress and ADD keep me wake and the next day i eather sleep for a greater part of the day and feel like shyte or have extreamly little sleep, fall asleep in class and get into shyte from my parents for failing engish.

i have the neccisary tools and skills to build this but would this help my condition?

thanx

Boris Legradic said...

Hey Cruel Regulator,

first off, I am a physicist, NOT a doctor, so don't take medical advice from me.

second, to answer your question: I don't think it would help you very much. If you think that you may be suffering from not enough sunlight, just step outside for half an hour a day - being in Australia, you should get more than enough light - the sun on a bright day has around 100 000 Lux. The only way I could see for you to be suffering from SAD is if you were spending all your time in a cave or something.

That being said, A SAD-box won't harm you either (except if you stare into the light for hours, so don't), so if you think it might help you, go for it. If nothing else, it is a fun little project.

If you really think you are suffering from depression, you _should_ go see a doctor - there is nothing to be ashamed of, it is a medical condition like any other illness, and many forms of depression can be treated successfully now.

Good luck,
Boris

Eric said...

Boris- Excellent project. I plan to build one. Also, as a state licensed Master Electrician in the state of Iowa I can say that your design is electrically sound and up to code. I deal with engineers on a daily basis who overthink the problem. This slows down the production of almost every job. 99% of the time, if you let them think they are smarter than you and drop subtle hints to what is actually right, they "solve" the problem eventually. Us "lowly" construction workers laugh about this regularly. Arrogance is a terrible thing. Kudos for calling people out on it.

Anonymous said...

check this out!!
http://depression.about.com/od/sad/bb/lightboxtherapy.htm
This is the most up to date information on the color, lux, lumen bulb type etc. for SAD suffers. I just built a light out of a 24' florescent box fixture with 2 daylight 875 lumen bulbs and a diffuser. It's sooo bright I feel like I need sun glasses but this article says it should be overhead not in your face,so with that adjustment I feel much better.
My doc says take vitamins A & D also, This helps too and in just 2 weeks I already feel more energy. My mood is already much improved.
certify ed

Boris Legradic said...

@Eric: Good to know I didn't fuck up somewhere - I tried to build it "sister-safe", but I know electrics only form the physics-side, so I am often a bit vague about "building to code" ;)

@Anonymous: Thanks for the link. I've also linked some papers in my follow-up post here

Post a Comment