Methods and Apparatus for Using Illumination Images Having Different Frequency Content and/or Resolutions To Facilitate Stereoscopic Depth Determinations

An apparatus comprising:

• a light projector;
• memory storing a digital representation of a first illumination pattern;
• a processor configured to:
• select, based on at least one of:
• i) a camera to surface distance (CTOSD), ii) a projector to object surface distance (PTOSD), or iii) both a CTOSD and PTOSD, an illumination pattern to use;
• project the selected illumination pattern on a surface;
• operate cameras including a first camera and a second camera to capture images of said illumination pattern on said surface, said images including a first image captured by the first camera and a second image captured by the second camera;
• and
• perform, using said first and second images, a stereoscopic depth determination, said stereoscopic depth determination determining a depth to said surface.

A depth determination method, the method comprising:

• projecting a first band limited illumination pattern onto a surface of an object, said first band limited illumination pattern having been generated by lowpass filtering a first image to generate said first band limited illumination pattern;
• operating a pair of cameras to capture images of said first band limited illumination pattern, said pair of cameras including a first camera that captures a first image of the illuminated surface and a second camera that captures a second image of the illuminated surface;
• and
• performing, using said first and second images, a stereoscopic depth determination, said stereoscopic depth determination determining a depth to said surface.

An apparatus, comprising:

• light projector for projecting an illumination pattern;
• a pair of cameras including a first camera and a second camera;
• and
• a processor configured to:
• control the light projector to project a first band limited illumination pattern onto a surface of an object 140, said first band limited illumination pattern having been generated by lowpass filtering a first image to generate said first band limited illumination pattern;
• operating the pair of cameras to capture images of said first band limited illumination pattern, said pair of cameras including the first camera that captures a first image of the illuminated surface and the second camera that captures a second image of the illuminated surface;
• and
• perform, using said first and second images, a stereoscopic depth determination, said stereoscopic depth determination determining a depth to said surface.