Optical Vortex Generator and Analysis

Harnessing spiral light for measurement !

Overview

Chiral materials absorb right- and left-circularly polarized light differently (circular dichroism). Optical vortices, however, carry orbital angular momentum; their topological charge l can take unlimited integer values (±1, ±2, ±3, …). Using this richer degree of freedom enables material characterization, chirality discrimination, and a new measurement modality (“optical-vortex dichroism”) beyond conventional circular dichroism.
Conventional vortex generators are limited to low-frequency modulation, leading to high noise and poor S/N. The invention engineers the optical system to achieve left–right vortex modulation at high frequency, reducing noise. We demonstrate detection of the “geometric twist” in twisted gold nanorod dimers (TND: paired, twisted nanoscale rods), suggesting defect detection in fine metallic wiring and applications in semiconductor, MEMS, and metamaterial inspection, as well as discovering new properties and enabling chirality identification.

Features・Outstandings

Product Application

・Optical vortex generator, material analysis instrument
・Defect inspection for semiconductors, MEMS, metamaterials

IP Data

IP No.　 ： Not published
Inventor ： TANAKA Yoshito, HASHIYADA Shun
keyword ： Optical vortex, Dichroism, Spectral measurement, Analysis methods, Analytical equipment, #Optical vortex dichroism, Circular dichroism