Wireless Prism Desk Lamp

I love desk setups; I am always on the hunt for nice looking setups so I can learn from them. I noticed that all best-looking ones had a desk lamp. Around the same time the lack of light started irritating me. I figured building a desk light would be a great project to try my hand at making something that is a little more looks focused. Since I am a geek, I have a prism as a desk ornament and I wanted to make it feel more special by giving it a light up base, so that is exactly what I did.

In this segment I am going to list all the parts needed for this project. I will provide links to the same or similar products on Aliexpress. This, because it is the store I use the most and because it has global reach.

• Prism:

The prism is the centerpiece of the desk lamp and the reason for building it.

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• LED Filament:

The LED filament is the perfect choice because it is cylindrical and thus can be used to lighten up every side. They are also very bright and will provide enough light for comfort.

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• Electronics Pins:

The LED filament is the perfect choice because it is cylindrical and thus can be used to lighten up every side. They are also very bright and will provide enough light for comfort.

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• Boost Converter:

Because the LEDs are mounted in series the amount of voltage needed to power them will be tripled from 3V to 9V. The battery only outputs 3.7V and needs to be boosted.

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• Charging Circuit:

This circuit is needed to charge the battery and protect it from over charge and discharge.

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• Battery:

The battery I used is an off-brand replacement Gameboy battery. It was the perfect size to fit in the case and had a reasonable capacity that lasts around 5 hours, this is more than enough light for those late-night working sessions.

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• PCB:

Because this is an impromptu project, I used a protoboard/ purfboard as the basis of this project. Luckily the holes lined up perfectly to make a triangle that the prims fits into.

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• M2x3 Threaded Insert:

These inserts will be used in the case to screw the PCB on. They are needed since screwing down the PCB might take some force and we do not want to strip any threads printed with the case.

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• M2x10 Screw:

For the screws I used flat topped hex screws. The top is flat and that makes it perfect to hold down the mesh and it looks nice.

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• Mesh:

Because this is an ornamental piece on the desk it should look nice. The protoboard however does not, because of this I chose to place a dust filter mesh over the PCB to hide it.

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• On/ Off Switch:

We should totally be able to turn the lamp on and off, to do that we will add a switch to the light.

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• Battery Level Sensor (Optional):

A while back I bought a few battery level indicators for future battery powered projects and I thought that this project would be a great first use for this part. This part isn’t necessary, if you do not value being able to see when the battery is getting low you can skip this.

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• SMD LED Blue (Optional):

This LED is needed to show if the battery is full or not. If you did not include the battery level sensor in your project you can skip this part as well.

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• SMD LED Red (Optional):

This LED is needed to show if the battery is below 25% charge. If you did not include the battery level sensor in your project you can skip this part as well.

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In this section I am going to list all the tools I used to build the project.

• Soldering Iron:

Obviously, you are going to need a soldering iron to connect all the parts together.

• Wire Cutter:

The wire cutter is needed to cut wires to length, truth be told scissors can also be used.

• Wire Stripper:

A wire stripper is needed to make the wire ready to be soldered.

• 3D Printer:

You are going to need a 3D printer to print the case with.

In this section I am going to list the consumables needed in this project.

• Wire:

We are going to need some wire to connect every component.

• Solder:

Solder is needed to solder all the components to the purfboard or each other.

• 3D Filament:

The case is 3D printed so you are going to need some filament. For this project I used marble gray filament.

We are going to start with your standard 40.4mm X 60.2mm
(1.59in X 2.37in) protoboard as a base. Put 3 piece of the LED filament in a triangle like shown on the image above.

The LED filaments has 2 pins, a long one and a short one with a hole in it. These pins should be alternatively connected to wire all the LEDs in series. In this image the first part of the code (F01) means the location of the hole that the pin should be inserted in and the second part (-L) means what pin should be inserted. L means the long pin and S the short pin with a hole in it.

Now when you soldered the filament onto the board you will have to do something you are not going to like. You will have to de-solder the LEDS again. Do not worry I did not make you solder them for fun. The holes that were used are full of solder now, we are going to need that in the next step.

Lastly, we must connect the long and short pins of the LEDs. This is done by soldering A09-S to B10-L and K10-S to L09-L.

To make the board prettier so it looks nice on your desk we are going to put a mesh over it. This mesh is originally meant to be used as a PC fan dust filter. This means that you will not be able to seethe board beneath it.

Cut a piece of the mesh the size of the purfboard and place it on it. Now with the soldering iron melt hole through it on the holes now filled with solder.

When the holes are made clear out the burnt plastic, place back the mesh and solder the LEDs back over the mesh. It should look something like the first picture above.

That looks a lot better does it not!

After that I soldered the 2 small SMD LEDs between two holes that looked nice to the eye. In my case the blue SMD was mounted between O06 and R06. The red LED was mounted between O09 and R09. Again, I used the soldering iron to melt holes for the LEDs and the used flush wire cutters to clear out the burned buts and cut the hole to a more precise size. It should end up looking something like the second picture above.

The electronics of this project are quite simple. The electronics just consists of battery charging circuit, battery level indicator and boost converter. All these circuits can be bought as individual parts and you just must connect the in and output pins.

First off, we are going to solder the boost converter to the protoboard. See the second picture above for refrence.

I changed the value of the boost converter to output 9V. After that I added solder to the pads of the converter, I placed the converter on the purfboard and heated to pads so it would stick to the purfboard. After that I bridged the outer pads and two of the converter pads to make the connection solid, so the part does not start flying around and shorting stuff. Shown in the third picture above.

It is also a god idea to connect two wires to the output pads of the board so that we will not have any problems later when we add the charging circuit over these pads.

After that we are going to add the battery level sensor to the purfboard, as seen in the forth picture above.

This is a stright forwad process, I just soldered a pin through the negative battery pin and soldered that to the purfboard. I also connecte the two bords with a pin through the battery 50% hole to connect the board on two points.

The last component that we are going to add to the board is the charging circuit, as seen in the fifth image above. This board will make it very easy to use a battery in the project.

I connected this part to the board by using three pins. The first one is located in out-, the second one in out+ and the third one in -. The mounting locations are encircled in yellow in the sixth picture above. These pins might need to be bent a little because they do not line up with the holes on the purfboard.

With all the parts mounted to the purfboard we can start connecting the parts to each other.

We are going to start with connecting the output of the charging circuit to the input of the boost converter. So, connect OUT- to VIN- and OUT+ to VIN+. This will turn the 3.7V output of the battery to the required 9V for the LEDs.

Second off we are going to connect the battery level indicator to the charging board. We do this by connecting B- on the charging circuit to – on the battery level indicator. After that we connect B+ and +.

Now before the battery indicator will work, we must short 2 pins on the button. This button is the on/ off switch for the module, and it will only show the power levels when the button is pressed. We are going to short the switch as shown in the first picture above.

We just must connect the LEDs to the corresponding pins on the battery indicator. This is straight forward enough but be sure check if you are connecting + to + and – to – on the LEDs. You can use the pre-installed LEDs to check if your orientation is correct.

Third off we are going to connect the boost converter to the LEDs. This is as straight forward as connecting the VOUT+ to G01-S and VOUT – to F01-L.

Now we are going to add a on/ off switch to the board. We are going to add it in between the battery and the charging circuit. The switch can be seen in the second picture above.

The pins on the switch have the perfect distance to be soldered to the big pads on the edge of the board. The top pin will be left unpopulated and acts as a dead zone. The middle pin will be connected to B+ on the charging circuit and the bottom pin gets connected to + on the battery. This way when the switch is in the down position there is a connection between the two wires and the electricity can flow.

Lastly connect the B- to the negative pin on the battery and everything should work!

I created the casing with some loose measurements, so I will not go into too deep a detail. I 3D printed the case. The files which I used are included in this instructables.

Now that everything has been soldered together and the case has been printed, we should put some threaded inserts into the screw holes. This is because it might take some force to hold the PCB down and printing included threads might get stripped. After inserting the threaded inserts, it should look something like the first image above.

Finally, when everything is assembled it should look something like the final two images. Place your prism inside of the triangle and you have got yourself a wireless prism desk lamp.

As you can see the lamp really gives off a lot of light. More than enough to light up the entire desk.

I hope you have enjoyed this instructable and that it will light up your desk like it did mine. If you are not going to replicate this project, I hope it inspired you to build something else that improves your life.

This is some kind of bonus step, if you are interested in a few learning points of the project this is where you are going to find them.

Next time I am going to cut the mesh a bit bigger than the PCB and fold it over the edges. This will give the lamp a much nicer look since places where the mesh folds upwards are places where you can see the PCB. This might make soldering a little more difficult.

The lights are a bit bright to sit just below eyesight. I think I am going to drop the voltage a little lower to make them dimmer. At a certain point, the individual LEDs will begin to show and make it look a lot less nice, but hey if I am not looking at it directly it might be worth it.

Next time I just might mount the LEDs on one layer of PCB, fold the mesh over that and sandwich it between a second layer. This will mean that I can solder all the parts to it in the beginning and just must connect the two layers. Making it way easier to build everything. I made a few folds in the mesh that might be visible bending it over to solder one of the mounting pins.