Opto-impedance spectroscopy and equivalent circuit analyses of AC powder electroluminescent devices.
Opt Express
; 25(12): A454-A466, 2017 Jun 12.
Article
em En
| MEDLINE
| ID: mdl-28788826
High energy photons can affect the dielectric response of AC powder electroluminescent devices (ACPELDs). In this paper, electroluminescent (EL), phosphor and dielectric films are photo-excited at peak wavelengths of 399 nm, 520 nm and 625 nm to identify the dielectric relaxation processes occurring in ACPELDs. The 399 nm illumination changes the frequency-dependent dielectric responses of both EL and phosphor films due to the photo-induced excitation of ZnS:Cu,Al phosphor particles. A higher illumination intensity increases the dipolar polarization in the resin matrix and enhances the Maxwell-Wagner-Sillars (MWS) effect at the particle/resin interfaces. Equivalent circuits relating to the relaxation processes present in the EL and phosphor films are derived. From the analyses of the circuit component values, a charge generation and accumulation process is proposed to explain these opto-impedance behaviors.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Revista:
Opt Express
Assunto da revista:
OFTALMOLOGIA
Ano de publicação:
2017
Tipo de documento:
Article