Depth camera assembly, head mounted display and method for depth sensing

Abstract

The present invention relates to a depth camera assembly, a head mounted display and a method for depth sensing. A depth camera assembly for depth sensing of a local area, including a structured light generator, an imaging device, and a controller. A structured light generator illuminates a localized area with structured light and includes an illumination source, a mounting element, and a diffractive optical element (DOE) mounted on the mounting element. The mounting element may have a plurality of adjustable positions relative to the lighting source based on firing instructions from the controller. DOEs use light emitted from an illumination source to generate a diffracted scanning beam that is projected into a localized area as structured light. The pattern of structured light is dynamically adjustable and unique for each adjustable position of the mounting element. An imaging device captures images of structured light reflected from objects in the local area. A controller determines depth information for the object based in part on the captured images.

Description

technical field [0001] The present disclosure relates generally to depth sensing, and in particular to offset diffractive optical elements for achieving adjustable resolution of structured light patterns for three-dimensional depth sensing. Background technique [0002] In order to achieve a robust user experience for depth sensing when using head-mounted displays (HMDs), it is important to create scanning devices that provide real-time dynamically adjustable lighting patterns. Most depth sensing methods rely on active illumination and detection. Conventional methods for depth sensing involve mechanical scanning or projection of fixed diffractive optical patterns using structured light or time-of-flight techniques. Time-of-flight based depth sensing uses a mechanically based mirror arrangement (scanner) to send short pulses into object space. Time-of-flight based depth sensing further uses high-speed detectors to time-gate backscattered light from objects to create high-re...

AI Technical Summary

Problems solved by technology

However, depth sensing based on fixed structured light is not robust to dynamic depth sensing where the spatial resolution of the illumination pattern needs to be tuned.

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