How to Build a Night Vision Camera

Materials Required

Webcam or Digital Camera (This article uses a webcam, but I have had successful results with a digital camera as well)
Processed Photo Negative
Superglue
Screwdrivers

LED Flashlight
Infrared LEDs
Soldering Iron
Solder
De-Soldering Tool (not required but useful)
Resistors (that correspond to voltages of flashlight and LEDs)
Angle Cutters or Wire Snips

Procedure

Building a nightvision camera is actually a rather easy mod to do with a very small amount of work. First, disassemble the camera and find the CCD (Figure 1). This is a small chip-like component directly under the lens or shutter (in a digital camera).

Disassembling the camera
Figure 1 - Disassembling the Camera

In front of the CCD, there is a small piece of irridescent glass (Figure 2). This is an infrared filter. Carefully remove the filter. You will not be replacing this.

The IR filter
Figure 2 - Removing the IR Filter

Cut a blank part of the processed negative (such as the end part) large enough to completely cover the CCD (Figure 3). Using the superglue, adhere the negative to a structure in front of the CCD (Figure 4) and reassemble the camera leaving the IR filter out of the assembly (Figure 5).

Cut a photo negative to fit the CCD
Figure 3 - Cut a Photo Negative to Cover the CCD

Adhere the negative over the CCD
Figure 4 - Adhere the Negative Over the CCD

Carefully Reassemble the Camera
Figure 5 - Carefully Reassemble the Camera

Carefully Reassemble the Camera
Figure 6 - Carefully Reassemble the Camera

You've now completed the actual night vision camera. But in order to see at night you will need to "illuminate" the dark--this is done with infrared LEDs. The human eye cannot see the infrared spectrum, but now your camera can.

Dissassemble an LED flashlight (Figure 7). De-solder the white-light LEDs from the printed circuit board (PCB) of the light making sure to note which side is the cathode of the LEDs (Figure 8). LEDs are diodes, this means that current can only flow through them in one direction. If, later, your LEDs don't seem to work, make sure you didn't install them backwards.

An Ordinary LED Flashlight
Figure 7 - An Ordinary LED Flashlight

Remove the White-Light LEDs
Figure 8 - Remove the White-Light LEDs

Next, observe the specifications of the infrared LEDs and the flashlight you are using. In my case, the LED forward voltage is 1.2 - 1.6 V and the flashlight supply is 4.5 V (and the correct resistors were already in use). Check the specifications you will be using in your setup to configure the correct resistance you need in the circuit. For simplicity sake, use an online LED resistance calculator to determine what type of resistors to use in conjunction with your LEDs. If you use incorrectly specified resistors or no resistors at all, you risk burning out your LEDs and burnt LEDs smell REALLY bad (trust me). Desolder the existing resistors and solder in the correct resistors for the IR LEDs (unless you got lucky like me). Making sure you correctly connected the anode and cathod to their correct contacts, solder the IR LEDs to the PCB (Figures 9 and 10).

Solder the IR LEDs in Place
Figure 9 - Solder the IR LEDs in Place

Solder the LEDs to the PCB
Figure 10 - Solder the LEDs to the PCB

Once you've done this, reassemble the flashlight and prepare your modded nightvision camera for use. Turn your IR flashlight on and darken a room and study the strange feeling of seeing a high intensity bright "light" through your camera's viewfinder/webcam window without seeing any light sources (Figures 11 and 12).

Homemade Nightvision
Figure 11 - Me, Using the Nightvision Camera in a Dark Room

You Can Make Out Writing With It as Well
Figure 12 - You Can Make Out Writing With It as Well