Stereoscopic object detection leveraging expected object distance

A head mounted display device, comprising:

• a see-through display;
• a first camera configured to capture a first image from a first perspective;
• a second camera configured to capture a second image from a second perspective, different from the first perspective;
• a logic machine;
• and
• a storage machine including instructions executable by the logic machine to:
• receive the first image taken by the first camera;
• receive the second image taken by the second camera;
• spatially changing two-dimensional positions of pixels in the first image relative to corresponding pixels in the second image by a spatial offset distance resulting in spatially offset first and second images;
• and
• recognize a target object imaged by corresponding pixels of the offset first and second images.

A method of finger detection, the method comprising:

• receiving a first image taken from a first perspective by a first camera of a head mounted display device, the first image including a finger of a wearer of the head mounted display device;
• receiving a second image taken from a second perspective, different from the first perspective, by a second camera of the head mounted display device, the second image including the finger of the wearer of the head mounted display device;
• spatially changing two-dimensional positions of pixels in the first image relative to corresponding pixels in the second image by a spatial offset distance resulting in spatially offset first and second images, such that a particular pixel of the offset first image depicts a same finger locus as a corresponding pixel in the offset second image only if the finger locus is at an expected reach distance of the wearer of the head mounted display device, the spatial offset distance being derived from the expected reach distance;
• and
• recognizing the finger of the wearer of the head mounted display device located at the expected reach distance and imaged by the offset first image.