Vectorial field propagation through high NA objectives using polarized Gaussian beam decomposition

N. Worku; H. Gross

doi:10.1117/12.2273919

25 August 2017 Vectorial field propagation through high NA objectives using polarized Gaussian beam decomposition

N. Worku, H. Gross

Proceedings Volume 10347, Optical Trapping and Optical Micromanipulation XIV; 103470W (2017) https://doi.org/10.1117/12.2273919
Event: SPIE Nanoscience + Engineering, 2017, San Diego, California, United States

Abstract

Scalar fields can be propagated through non-paraxial systems using the Gaussian beam decomposition method. However, for high NA objectives, this scalar treatment is not sufficient to correctly describe the electromagnetic fields inside the focal region due to high ray bendings, which result in a significant change in the polarization state of light. To model these vectorial effects, the Gaussian beam decomposition method has to be extended to include the polarization state of light. In this work we have combined it with the three dimensional polarization ray tracing in order to propagate vectorial fields through high NA optical systems. During the Gaussian beam decomposition, the polarization state of each individual beamlet is represented by a polarization vector [𝐸_𝑥, 𝐸_𝑦, 𝐸_𝑧 ] associated with its central ray. Individual Gaussian beams are then propagated through the system using the complex ray tracing method. The effect of the optical system on the polarization state of each beam is computed by applying the three dimensional polarization ray tracing of the corresponding central rays. Finally the individual beams are superposed coherently in the plane of interest resulting in the complete vectorial field. We apply the proposed method to compute the vectorial field inside the focal region of a high NA microscope objective lens and compare our result to the vectorial Debye integral method. We find that the Gaussian beam decomposition method overcomes serious limitations of algorithms relying on Fourier transforms, i.e. the field sampling requirements are less critical in high NA focusing and in the presence of large aberrations. However, sharp edges in the amplitude profile are difficult to handle as they should be replaced with smooth Gaussian edge.

Citation Download Citation

N. Worku and H. Gross "Vectorial field propagation through high NA objectives using polarized Gaussian beam decomposition", Proc. SPIE 10347, Optical Trapping and Optical Micromanipulation XIV, 103470W (25 August 2017); https://doi.org/10.1117/12.2273919

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available