Directional phase-unwrapping algorithm and phase shift technique on hydrogel.
Appl Opt
; 60(13): 3901-3908, 2021 May 01.
Article
en En
| MEDLINE
| ID: mdl-33983328
ABSTRACT
Refractive index microstructures, which can be written by multiphoton absorption with femtosecond lasers, have many applications. Here we present a directional phase-unwrapping algorithm with phase-shifting technique and apply it to the metrology of hydrogel microstructures. A staircase phase-unwrapping algorithm is demonstrated. This fast quality-guided path phase-unwrapping applies well to situations that are geometrically well defined and is quite tolerant of phase noise. To achieve precise very small phase shifts, we also present a slant angle technique on a DC servo stage along with phase shift measurement, allowing us to achieve 6.5 nm step sizes.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Appl Opt
Año:
2021
Tipo del documento:
Article