A Preview on the NerdConv1
July 15, 2012
Today my wife went to the cinema with my kids and I took the resulting moment of quietness at home to build up two new NerdCam1 modules. I wanted to have them ready as the new base PCB for the NerdConv1 - my new video side-by-side converter - is approaching.
The two new cams with customized optics and spacers for firm attachment
The lens sockets are still taken from my old commercial cam modules. The lenses are available here but can also be bought from ebay or elsewhere. Please note that those rather cheap lenses usually do not have an infrared cutoff filter coating. Hence this filter is mounted on top of the imager chip of the module.
Packaging of the IR-filters I have bought here
Close-up of the filter glued with flexible glue on the imager chip
Here are two photos taken by my PCB manufacturer showing the NerdConv1 base PCB. It is still double sided with some tricks applied for having digital and analog ground planes. The eight big holes are for accessing the screws of the lens holders when the camera modules are in place. This is helpful for final adjustments of the optics.
Top layer - all SMDs are placed here as well as the XuLA-200 FPGA board
Bottom layer - both camera modules are plugged-in from this side
The idea is to have one board which carries everything that is needed in order to do the stereo signal conversion. In addition to my initial plans I included support for stereo audio via two miniaturized electret microphones POW-1644L-LWC50-B-R.There will be some LED's for status indication, some push buttons for switching between user-defined modes of operation, and some potentiometers to tune brightness, hue, or saturation of the camera modules. During my trials I noticed that especially the brightness adjustment between both cameras is important. Different brightness levels at both cameras are extremely disturbing when observed with 3D-video goggles. Finally I included some headers for future expansion boards. Those headers make a number of signals available such as power supply, I2C, the main 27MHz clock, two GPIO pins as well as the 8-bit-wide BT.656 digital output signal from the FPGA. So if anyone in future wants to build a video compressor for digital audio/video transmission then the board will be prepared.
3D-preview of the board - not all components are visualized with real dimensions
If everything goes well then my next post will be on my first trials with the new NerdCam1/NerdConv1 device combination.