Diffractive optical elements with mitigation of rebounce-induced light loss and related systems and methods

US11067808B2 · kind B2 · utility

Assignee

• Magic Leap, Inc. · US

Inventors

• Jeffrey Dean Schmulen · Austin, US
• Neal Paul Ricks · Plantation Gardens, US
• Samarth Bhargava · Saratoga, US
• Kevin Messer · Mountain View, US
• Victor Kai Liu · Mountain View, US
• Matthew Grant Dixon · Monet, US
• Xiaopei Deng · Cedar Park, US
• Marlon Edward Menezes · Austin, US
• Shuqiang Yang · Austin, US
• Vikramjit Singh · Pflugerville, US
• Kang Luo · Austin, US
• Frank Y. Xu · Round Rock, US

Key dates

• Filing date: Jul 23, 2019
• Grant date: Jul 20, 2021
• Expiry date: Jul 23, 2039

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B2027/0178
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Display devices include waveguides with in-coupling optical elements that mitigate re-bounce of in-coupled light to improve overall in-coupling efficiency and/or uniformity. A waveguide receives light from a light source and/or projection optics and includes an in-coupling optical element that in-couples the received light to propagate by total internal reflection in a propagation direction within the waveguide. Once in-coupled into the waveguide the light may undergo re-bounce, in which the light reflects off a waveguide surface and, after the reflection, strikes the in-coupling optical element. Upon striking the in-coupling optical element, the light may be partially absorbed and/or out-coupled by the optical element, thereby effectively reducing the amount of in-coupled light propagating through the waveguide. The in-coupling optical element can be truncated or have reduced diffraction efficiency along the propagation direction to reduce the occurrence of light loss due to re-bounce of in-coupled light, resulting in less in-coupled light being prematurely out-coupled and/or absorbed during subsequent interactions with the in-coupling optical element.