Mixed refractive gradient index optics for time-of-flight sensors

Abstract

A time-of-flight sensor with mixed refractive gradient index optics. A time-of-flight (TOF) imaging subsystem may receive optical information along an optical path at an imaging plane. A mixing lens may be coupled with the TOF imaging subsystem and disposed in the optical path such that the imaging plane lies substantially in a focal plane of the mixing lens. The hybrid lens may include a gradient index (GRIN) lens portion (210) less than a quarter pitch and a refractive lens portion (220) having a convex optical interface. The portions of the hybrid lens together produce a combined focal length defining a focal plane. The hybrid lens is designed such that the combined focal length is less than the quarter pitch focal length of the GRIN lens portion (210) and has a smaller spherical aberration than either of the lens portions.

Description

technical field [0001] The present invention generally relates to optical devices integrated into personal electronic devices. More particularly, embodiments relate to mixed-refractive gradient index optics for time-of-flight sensors for integration into portable personal electronic device environments, such as cameras used in smartphones. Background technique [0002] In the past, photography was a discipline reserved for those with the expertise and equipment. Over the past few decades, innovations in digital photography hardware and software, and the worldwide proliferation of smartphones with integrated digital cameras, have put digital photography within the reach of billions of consumers. In this environment of ubiquitous access to digital photography and videography, consumers increasingly expect to be able to capture moments quickly and easily using their smartphones. Advances in digital photography include advances in capturing three-dimensional information for va...

AI Technical Summary

Problems solved by technology

Traditionally, it has been difficult to integrate this time-of-flight technology into portable digital electronic applications such as smartphones

For example, some traditional approaches rely on relatively large optics and / or specialized illumination sources that are not suitable for the space constraints of many portable digital electronics applications; while other traditional approaches are often not reliable or accurate enough to support more advanced functions

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