Title: Optical Ranging Apparatus
Inventors: Edward H. Adelson
United States Patent Number: 5,076,687
Date: 1991
An optical ranging apparatus is provided which resolves the depth of objects in an object field of a main lens. Light
is directed by the main lens to a lenticular array consisting of an array of lenticules each of which generates an
image of the lens surface. Each of the generated images is directed to a photodetector array divided into macropixels
each of which receives one of the lenticule images. Each macropixel is made up of a number of subpixels, each of
which is a discrete photodetector element and generates an electrical signal proportional to the intensity of light
upon it. A data processor receives the signals from the subpixels and assembles subimages, each of which consists of
one subpixel from each macropixel. Each subimage represents a view of the entire object field through one portion of
the main lens. The data processor determines depth of objects in the object field by comparing the parallax between
subimages. A diffuser may be provided between the object field and the lenticular array to low pass filter light from
the object field and reduce aliasing. A field lens may also be provided between the main lens and the lenticular
array to redirect light from the main lens and prevent skewing of the light reaching the macropixels. The images from
the lenticular array may be relayed to a photodetector array set back from the lenticular array by using a relay
lens.