Focusing Optical Phased Array for Optically Enabled Probing of the Retina with Subcellular Resolution

TL;DR

This paper introduces a silicon-nitride-based optical phased array capable of focusing and steering light at 522 nm for high-resolution retinal probing, enabling targeted cellular excitation with subcellular precision.

Contribution

It presents a novel integrated optical phased array with built-in focusing and steering, combining wavelength tuning and thermo-optical phase shifters for precise retinal imaging.

Findings

Achieves 1.4 um beam diameter at focus for subcellular resolution

Enables targeted cellular excitation through combined wavelength and thermo-optical control

Operates at 522 nm for retinal applications

Abstract

We present a silicon-nitride-based optical phased array with built-in focusing and steering capability, that operates at 522 nm and is aimed at complementing a micro-electrode array for joint electrical and optical probing of retinal tissue. It achieves subcellular resolution with a beam diameter of 1.4 um at a focal point located above the chip. Targeted cellular excitation can be achieved by steering the beam through a combination of wavelength tuning and simplified thermo-optical phase shifters with a single electrical input for each of transverse beam steering and selection of the focal plane.