Simple Serial Imager

www.whitewing.co.uk/imager

Update Oct 2008 - This product is undergoing a redesign due to the sensor being made obsolete by the manufacturer. 
The new version will use  a colour sensor ( but will  be able to produce monochrome output formats and a removable IR cut filter  for IR operation), and have enough RAM for    full-resolution capture. Other general specs will be similar to what is described  below.

Timescale TBD due to being busy on other projects - please email if you would like  to be updated on progress.

Low cost, low-resolution monochrome image sensor with serial interface for easy interfacing to microcontroller based systems. based on a CIF (352x288) image sensor and an ARM processor to capture image data and output in various formats to suit low-end embedded applications.

Possible applications : Robotics, automatic inspection, interactive lighting, image recognition, remote monitoring, cool gadgets... suggestions..?

Basic sensor resolution: 352 x 288 x 8bpp ( CIF) monochrome (with good near-IR sensitivity for IR applications). 1/5" sensor. A colour version is planned.

The actual output resolution and framerate are fully configurable and highly flexible, however the output resolution is limited to permutations that fit the ~30kbyte internal buffer memory  size.  Non-realtime full-resolution images can be captured over several frames.

Software pan/zoom, independently selectable in X and Y directions. Pixels may be sampled at programmable intervals, e.g. every pixel, every second pixel, every 3rd pixel etc., with sensor-pixel resolution positioning to allow software pan/zoom over the sensor image area.
Bit depth is programmable to allow increased resolution at lower bit depths.
Programmable lookup table for mapping of pixel data values to output data). Sensor pixel clock rate is software controllable, for applications requiring specific timing. .

Software selectable fixed/automatic gain/exposure controls. 

Interface : Serial (TTL Uart, 3.3v, 5V tolerant), with very wide range of baudrates up to 3mbits/sec .

Directly drives a Nokia style 128x128 pixel LCD for image previews, diagnostics. etc. This works in parallel with the normal serial output (although it can slow down the framerate in some cases).

Onboard 2kbyte EEPROM allows pre-configuration of all parameters for simple "plug & go" operation in the target application.

Standard M12 lens holder as standard, allowing wide choice of low-cost CCTV board camera lenses. PCB holes allow for alternate lensholders with screw spacings from 17.5 to 24mm pitch. Standard lens TBD but will probably be 2.1 or 2.8mm, as this gives a wide range of fields of view in combination with the software zoom capability. (Compared to conventional CCTV board cameras, this sensor has a rather smaller 1/5" image area, so the angular field of view is somewhat smaller, and hence less distorted that it would be on a TV-resolution sensor).

16 pin 0.1" 2-row header connection for PCB mount or IDC ribbon cable. Connector pinout can also connect to a FTDI TTL-232R cable directly for power and data, e.g. for configuration & test.

Additional features under consideration - these are all possible with the hardware, and may or may not happen, depending on demand..

• Alternative interfaces : I2C slave, SPI master/slave. Auxilliary serial port for daisy-chained, addressable camera networks, or double the data throughput from simultaneous serial outputs

• Direct output of DMX format data for lighting applications (with external RS485/422 line driver).

• Compression (simple, e.g. Run-length, Huffman - JPEG is unlikely!)

• SRAM piggyback board for higher resolution

• High resolution spot-position detection for sensing applications

• Sync output for controlling external illumination. Automatic control of external illumination by auto-exposure control.

• Multi-camera addressable network support, via RS485, daisychaining and bussed TTL UART modes

Mechanical dimensions (mm)

Demo/eval PCB with Nokia LCD