Air pocket structures for promoting total internal reflection in a waveguide

US12044851B2 · kind B2 · utility

Assignee

• Magic Leap, Inc. · US

Inventors

• Xiaopei Deng · Cedar Park, US
• Vikramjit Singh · Pflugerville, US
• Shuqiang Yang · Austin, US
• Kang Luo · Austin, US
• Nai-Wen Pi · Plano, US
• Frank Y. Xu · Round Rock, US

Key dates

• Filing date: Dec 20, 2019
• Grant date: Jul 23, 2024
• Expiry date: Jan 11, 2041

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B2027/0174
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

Recesses are formed on a front side and a rear side of a waveguide. A solid porogen material is spun onto the front side and the rear side and fills the recesses. First front and rear cap layers are then formed on raised formations of the waveguide and on the solid porogen material. The entire structure is then heated and the solid porogen material decomposes to a porogen gas. The first front and rear cap layers are porous to allow the porogen gas to escape and air to enter into the recesses. The air maximizes a difference in refractive indices between the high-index transparent material of the waveguide and the air to promote reflection in the waveguide from interfaces between the waveguide and the air.