Picture of Jar Lantern

The Jar Lantern is a contemporary take on the traditional gas lantern. It was inspired by seeing sunlight refract through my glass water bottle one afternoon, and thinking to myself that it was a bit like carrying a jar full of light. This brief moment of illumination sparked something in my mind that made me wonder how I could capture this experience more permanently.

While trying to bottle light may be a fool's task, I could at least try to recreate the sense of magic I had briefly experienced. After mulling over various methods of accomplishing this, I decided to make a jar with an illuminated floating light bulb. The beauty of this seemingly impossible object is that the light bulb has no clear power source, yet it seems so natural and familiar. The Jar Lantern tends to leave people both taken and dumbfounded by its simplicity.

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Step 1: Go Get Stuff

Picture of Go Get Stuff

You will need:

(x1) Jar**
(x1) CFL Bulb
(x1) Disposable camera
(x1) AA battery holder
(x1) Switch
(x1) Roll of magnet wire

**You can get jars with lids online, but only by the dozen from Daiso.

Step 2: Open the Disposable Camera

Picture of Open the Disposable Camera

Open up the disposable camera case. Be mindful not to touch the large capacitor which could potentially give you a nice jolt.

Step 3: Cut Away the Capacitor and Flash

Picture of Cut Away the Capacitor and Flash

Discharge the capacitor by bridging the leads with a long screwdriver that you don't care much for. Be careful not to be touching the metal part of the screwdriver while doing this. Once discharged, cut it from the board so that it will not recharge.

Also, cut the flash tube away from the circuit board.

Step 4: Hack a CFL

Picture of Hack a CFL

Use a pair of diagonal cutting pliers to make a hole in the plastic body of a CFL bulb.

Next, use this hole to insert a screwdriver and gently pry the the base apart from the glass tube.

Finally, unwind the CFL tube's wires from the posts on the circuit board.

Step 5: Bridge the Switch

Picture of Bridge the Switch

Remove the push tab atop the flash charge switch.

Solder the switch's terminals together.

Step 6: Prep the CFL Bulb

Picture of Prep the CFL Bulb

Scrape the coating off the wires coming out of the CFL bulb using a razor blade.

Twist the wires together and tin them with solder.

Step 7: Remove Extra Parts

Picture of Remove Extra Parts

Remove any parts the stick out from the board such as battery terminals. However, remember to make note of which terminals on the underside of the board they are connected to for future reference.

I also removed the wire connecting the top of the trigger transformer to the flash tube for the heck of it.

Step 8: Trim the Circuit Board

Picture of Trim the Circuit Board

Trim away any corners that have unnecessary electronic traces (or no traces at all).

Step 9: Prep the Magnet Wire

Picture of Prep the Magnet Wire

Strip away 1/2" of plastic coating from both ends of two 3" pieces of magnet wire using a razor blade.

Step 10: Hack a Camera Flash

Picture of Hack a Camera Flash

Now is time to connect the wires to the board that will power the light.

Solder the first magnet wire to one of the terminals connected to the ground plane.

Solder the other wire to the terminal of the inverting transformer that the diode is connected to.

*** If you are confused, a more hands on way of figuring this out is to use aligator clip jumper cables to connect the battery to the board. The board should now be live, so be careful of high voltages!

Using another cable, connect one of the bulbs leads to ground. Finally, connect a fourth cable to the other battery lead. Briefly touch this wire to various spots on the board until the bulb lights up. Once its lit, you have found the proper connection. ***

Step 11: Connect a Switch

Picture of Connect a Switch

Trim the battery holder's red wire in half. Solder the trimmed pieces to the center terminal of the switch and the red wire still connected to the battery holder to the switch's outer terminal.

Step 12: Drill the Lid

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Drill a 3/16" hole near the outer part of the lid for mounting the switch.

Step 13: Mount the Switch

Picture of Mount the Switch

Pass the switch up through the underside of the lid and lock it in place with its mounting nut.

Step 14: Connect Power to the Camera Flash

Picture of Connect Power to the Camera Flash

Solder the red wire from the switch to the spot on the camera flash circuit board where the positive terminal of the battery was connected.

Solder the black wire to ground.

Step 15: Hot Glue

Picture of Hot Glue

While I am not normally a fan of hot glue, it is the perfect adhesive for connecting the circuit board and battery holder to the inside of the lid.

Center them inside the lid and then glue them in place as flush to the lid as possible.

Use a generous amount of glue, but be mindful of not getting any on the lid's inner edge, or it will no longer twist shut.

Step 16: Connect the Bulb

Picture of Connect the Bulb

Solder one of the magnet wires to each of the CFL bulb's leads.

Step 17: Insert the Battery

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Insert the battery into the battery holder.

Step 18: Twist On

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Twist the lid onto the jar.

Step 19: Power!

Picture of Power!

If the lantern is not already on, power it up by flicking the switch.

Step 20: Illuminate the Darkness

Picture of Illuminate the Darkness

Go forth and make good use of your new lantern.

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Craig M1 year ago

How long will the batter run the CFL?

What about using an LED bulb?

kd1uc Craig M6 days ago

No, an LED bulb will not work for this. The technology is completely different. The real purpose of this instructable is to re-purpose a dead CFL where the circuit died but the bulb part is still good. In a CFL bulb the voltage is stepped up (300 volts), in an LED bulb the voltage is stepped down (2 to 3 volts).

Hope this helps.

Miramithe Craig M2 months ago
The answer to that is a bit complicated, and at the same time not. Ohms law is the answer, but to run those cfl you need a high frequency high voltage and LEDs like low voltage dc, but you can use a joulethief for the LEDs. By theory you could have double battery life on LEDs vs cfl cos cfl have around 50lm/W light output and led can have about 100lm/W.

Cool instructable, thanks for sharing OP. I too am curious to know if an LED bulb would be a better choice in terms of battery runtime...maybe the OP hasn't responded because LED bulbs are more difficult to modify? I really don't know...

coryvr039 months ago

Hey Guys, i am having an issue getting the bulb to light. I am an extreme beginner into the electronics world. i have tried two bulbs and two different styles of disposable camera boards. What is the desired voltage at the end of the magnet wires? I place my volt meter across the two wires and i get 295v with one board and 360v when i use the other board. Any ideas what i am missing? is there a special type of CFL i should be using? Any help would is greatly appreciated. Thanks in advance.

kd1uc coryvr036 days ago

If you could post some pictures we might be able to see something you missed. The only thing that comes to mind at the moment is that the bulbs are bad. If you cracked the seal on the tube it won;t work. What is the voltage when the bulb is connected? I had to use 3 volts to get mine to light.

Search joulethief and look at solar powered garden lights, there you have some nice beginner circuits.
this is no way a project for an extreme beginner. try low voltage leds or timer circuits
catfisher812 months ago
could one of those cheap solar yard lights be used to charge the battery during the day? maybe somehow mount the solar panel to the top?

Hey, you stole my idea :)

I did think of that because I have a few of those lights for just such experiments. The only problem I am having is my light needs 3 volts to light the bulb so it would eat up two solar panels.

Sounds like a good idea! Might as well give it a try and post up your results
SamuelA11 month ago

what if i dont have an old camera?

Those are the disposable cameras, which you can buy just about anywhere for a cheap price.

An example:

One more thing; They're mostly sold in 3 packs or so online, so go to a store to buy individual ones.

JohnS5513 days ago

Great project and I built one but my bulb doesn't seem to light up all the way. It only lights up the top bar and the rest is dark. Using 1 AA Battery anyone know how to fix?

drosenkranz made it!13 days ago
thank you for this awesome instructable it took me about 20 min
ArduinoDeXXX made it!1 month ago

Thank you for your Instructable. I have tried it
using stuff gotten in Japan. It requires some changes from yours to light. I
feel your project is wonderful. I would like to introduce yours with these
changes to Japanese Instriuctables if you don’t mind.

Picture 13.jpg

I used a circuit board of FUJI instead of KODAK. And I added 5-step-dimmer to it. The lantern based on yours has been posted to Japanese site of instructables.

Machine translation of web browser might help you to read it.

Liam.great98 made it!5 months ago

I lookedall over the dollar store for a plastic jar but couldn't find one. I had to use a glass jar with a metal lid, but that wasn't a problem because thee are no wires touching the lid. The only thing I had to purchase was the tiny switch, so it was totally woth it! Also I didn't use the original pcb I just desoldered the transfomer, transistor, and resistor and soldered them together on the transformer. I also didn't use an AA battery holder, to save space I just soldered onto the battery and glued it on the lid.

Can you teach me?

so beautiful!

景吳2 months ago

I can use alternatives to complete it anyway?

A complete circuit of it?

mgingerich2 months ago
cain26222 months ago
FugiFilm, sorry
cain2622 made it!2 months ago
I used a fug film disposable camera and learned that it only puts out about 150 volts. I compensated by using 2 AA 's. Works great, thanks.
waraji2 months ago

Fun project, but you should give a mercury warning. Since you haven't, I will:

Be careful regarding potential CFL bulb breakage. The mercury danger is real. Mercury poisoning is no fun.
The Texas Commission on Environmental Quality refers to this PDF for cleanup instructions. Don't vacuum!
Vacuuming spreads the contamination. Read this PDF.

KingW12 months ago

If you do not how to do this board

customboss2 months ago
Awesome idea and instructable!
Dop132 months ago
This is a nice instructable. I am going to mak one!
akarod792 months ago
Thanks, awesome idea. I was looking for a nice easy project to do with my son since he's been learning about electronic circuits in school. This will be perfect!
ggrookett2 months ago
This looks like a great project going to try this sometime with hopefully the same great results you got.

For those who would prefer to make their own circuit board, I found all of the parts here:

All you need is the following:

1- XFT-5383-1.5v works with just one battery

1- 2SD882 transistor pin out normally ECB

1- 1K resistor

The CFL board I found also had a transformer about the same size so conceivably the round circuit board could be adapted to hold the 300 volt circuit.. If my calculations are correct, I can make one with a CP300H battery that should last about an hour. I can charge it through the base too.

pmck BurgersBytes2 months ago

cool, Ill use this and let you know how it works

Wow, that looks awesome!

rdaly42 months ago
I enjoyed reading this. I could follow it easily and it provides wonderful base to expand on for future project planning. One of the pictures you posted has you carrying the lantern towards a fence that says unsafe area. It leads me to a question. Does this light qualify as grounded ? If it does it would allow it to be used in a whole slew of environments where an ungrounded light of this type could not be used.
cobourgdave2 months ago

Nice instructable- recycling old stuff and as a useful standby light during power outages. Will definitely will try. Thanks

QkillhawkNL8 months ago
For extending the time you have light with the lamp, you could use multiple AA battery's in parallel for more miliamps
BurgersBytes made it!1 year ago

Mission accomplished! I managed to find a circuit small enough to put inside of the base and put it all back together. The bulb now runs from a AA battery hooked to the AC socket base. It uses about 230 ma when on.

Beware of the other transformer. When the picture button is pressed with the flash charged it can create over 1000 volts to charge up the flash bulb. The plate wire is often out in the open so disconnect the battery and discharge the capacitor before proceeding further. The voltage will not kill you, but impacts with nearby objects could!

Anyhow, here is a picture and a link to the entire process:


have an idea instead of that circuits maybe use some discharge or died cfl and deposed the casing not the parts inside because can be extra parts and ... put inside the led in the cfl filament and just put some hot glue or industrialized super glue!!!!! and the circuits...........secret!!!!!!!!!!!! hahaha its much more last longer that the cfl with a filament and most efficient at all!!!!!

Apparenbtly the stuff INSIDE the tubes are toxit, so might want to NOT do that. Just saying.

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