VCSEL narrow divergence proximity sensor

A proximity sensor which uses very narrow divergent beams from Vertical Cavity Surface Emitting Laser (VCSEL) for the illumination source is disclosed. Narrow divergent beams in the range 0.5 to 10 degrees can be achieved to provide high proximity sensing accuracy in a small footprint assembly. One...

Full description

Saved in:
Bibliographic Details
Main Authors Ghosh, Chuni, Seurin, Jean-Francois
Format Patent
LanguageEnglish
Published 19.07.2022
Subjects
ANALOGOUS ARRANGEMENTS USING OTHER WAVES
BASIC ELECTRIC ELEMENTS
DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES
DEVICES USING STIMULATED EMISSION
ELECTRICITY
LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION ORRERADIATION OF RADIO WAVES
MEASURING
PHYSICS
RADIO DIRECTION-FINDING
RADIO NAVIGATION
TESTING
Online AccessGet full text

Cover

More Information
Summary:A proximity sensor which uses very narrow divergent beams from Vertical Cavity Surface Emitting Laser (VCSEL) for the illumination source is disclosed. Narrow divergent beams in the range 0.5 to 10 degrees can be achieved to provide high proximity sensing accuracy in a small footprint assembly. One approach to reducing the beam divergence is to increase the length of the VCSEL resonant cavity using external third mirror. A second embodiment extends the length of the VCSEL cavity by modifying the DBR mirrors and the gain region. Optical microlenses can be coupled with the VCSEL to collimate the output beam and reduce the beam divergence. These can be separate optical elements or integrated with the VCEL by modifying the substrate output surface profile or an added a transparent layer. These methods of beam divergence reduction are incorporated into various embodiment configurations to produce a miniature proximity sensor suitable for cell phones and tablets.
Bibliography:Application Number: US201716470899