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.

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 the jars used in this project online, but only by the dozen from Daiso.

(Please note that some of the links on this page contain Amazon affiliate links. This does not change the price of any of the items for sale. However, I earn a small commission if you click on any of those links and buy anything. I reinvest this money into materials and tools for future projects. If you would like an alternate suggestion for a supplier of any of the parts, please let me know.)

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

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.

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.

Remove the push tab atop the flash charge switch.

Solder the switch's terminals together.

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.

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.

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

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

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. ***

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.

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

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

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.

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.

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

Insert the battery into the battery holder.

Twist the lid onto the jar.

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

Go forth and make good use of your new lantern.