Share Email Print

Proceedings Paper

Widely tunable electrically pumped 1050nm MEMS-VCSELs for optical coherence tomography
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

In recent years, MEMS-tunable VCSELs have emerged as a leading swept source for optical coherence tomography imaging. At the ophthalmic imaging wavelength of 1050nm, optically pumped MEMS-VCSELs (MEMS-oVCSELs) have previously achieved >100nm tuning range and repetition rates approaching 1Mhz, enabling high-resolution and high-speed eye imaging. Electrically pumped MEMS-VCSEL technology (MEMS-eVCSEL) is a critical need for many emerging low-cost high-volume applications, but thus far tuning range has lagged substantially behind optically pumped devices. In this work, we demonstrate 97nm continuous tuning range in a MEMS-eVCSEL operating near 1050nm, and >100nm total tuning range, representing the widest tuning ranges achieved to date, and rivaling the performance of optically pumped devices. Our devices employ a strain-compensated InGaAs/GaAsP gain region disposed on a wideband fully oxidized GaAs/AlxOy back mirror. A deposited top mirror rests on a flexible dielectric membrane separated by a variable airgap from the underlying gain region. Application of voltage between the dielectric membrane and a bottom actuator contact on the top of the gain region creates an electro-static force which pulls the suspended mirror down, contracting the airgap and tuning the device to shorter wavelengths. In this 3-terminal device, the bottom actuator contact doubles as the laser anode. Current injection proceeds from the anode to the cathode at the back of the GaAs substrate through a lithographically defined low-loss current aperture, enabling reproducible aperture size and reproducible single-mode performance. These devices offer promise for many emerging high-volume imaging applications.

Paper Details

Date Published: 24 February 2020
PDF: 8 pages
Proc. SPIE 11300, Vertical-Cavity Surface-Emitting Lasers XXIV, 113000S (24 February 2020); doi: 10.1117/12.2543819
Show Author Affiliations
V. Jayaraman, Praevium Research, Inc. (United States)
Christopher B. Burgner, Praevium Research, Inc. (United States)
John Carter, Praevium Research, Inc. (United States)
Iana Borova, Praevium Research, Inc. (United States)
Nate Bramham, Praevium Research, Inc. (United States)
Chad Lindblad, Praevium Research, Inc. (United States)
Anthony Cazabat, Praevium Research, Inc. (United States)

Published in SPIE Proceedings Vol. 11300:
Vertical-Cavity Surface-Emitting Lasers XXIV
Luke A. Graham; Chun Lei, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?