SPC2 Camera

Technical Specifications

  • Camera9 MP USB 3.0 Color Point Grey Grashopper 3
  • Imaging Lens0.508X, 1″ Format Telecentric Lens
  • Illumination – Pulsed White LED, Darkfield
  • Exposure Time – 10 to 60 μs
  • Field of View – 2.5 cm x 2.0 cm
  • Pixel Size (Object Space) – 7.4 μm
  • Optical Resolution – 32 lp/mm @ 30% contrast
  • Depth of Field – 400 μm @ 32 lp/mm @ 20% contrast
  • High-Resolution Imaged Volume – 0.2 mL
  • Blob-Detection Imaged Volume – Up to 10 mL
  • Embedded System – 1.8 GHz Big-Little Quad Core ODROID-XU3, 2 GB RAM
  • Image Processing – OpenCV


SPC2_res_targ_90mm_50mm
The image to the right shows the 1951 USAF resolution test chart as recorded by the SPC2 camera. The chart features groups of line-pairs of increasing spatial frequency (decreasing distance between bars). The image shows groups 2 through 5 are being resolved by the camera with Group 5, element 1 being the spatial frequency at which the camera is no longer able to resolve the bars with sufficient contrast. Group 5, Element 1 corresponds to a spatial frequency of 32 line-pairs-per-millimeter (lp/mm) and a bar width of 15.63 μm. The line plot below confirms this result and shows that we achieve a contrast of better than 30% at 32 lp/mm.