Comparative and quantitative analysis of white light-emitting diodes and other lamps used for home illumination

Abstract

We compared the photometric and radiometric quantities in the visible, ultraviolet, and infrared spectra of white light-emitting diodes (LEDs), incandescent light bulbs and a compact fluorescent lamp used for home illumination. The color-rendering index and efficiency-related quantities were also used as auxiliary tools in this comparison. LEDs have a better performance in all aspects except for the color-rendering index, which is better with an incandescent light bulb. Compact fluorescent lamps presented results that, to our knowledge, do not justify their substitution for the incandescent light bulb. The main contribution of this work is an approach based on fundamental quantities to evaluate LEDs and other light sources. Downloaded From: http://opticalengineering.spiedigitallibrary.org/ on 05/15/2015 Terms of Use: http://spiedl.org/terms

Espectrômetro digital. Uma proposta de construção de um experimento de Física Moderna para o ensino remoto

“…Dando sequência aos testes do experimento, foi realizada uma medida com uma lâmpada incandescente. Como pode ser visto na Figura 12 (b), assim como previsto, o espectro da lâmpada incandescente tem o comportamento mais próximo contínuo, sem a existência de muitos picos que podem prejudicar o olho humano, como ocorre na lâmpada fluorescente (Rubinger, et al 2015). A seguir foi utilizada uma lâmpada LED.…”

Determination of thickness and refractive index of SiO2 thin films using the cross-entropy global optimization method

“…The optical thickness parameters are normally determined by the ellipsometry technique (Garcia-Caurel et al 2013, Losurdo et al 2009), but due to the high cost and complexity, a low-cost alternative was sought. Using non-destructive reflectance measurements through a UV-VIS-NIR spectrometer and then modeling the data with theoretical predictions that depend on the refractive indices belonging to the air/film/substrate set and the film thickness (Rubinger et al 2015, Jesus et al 2021). Thus, we present the results of modeling reflectance measurements using the cross-entropy (CE) global optimization method (Oliveira et al 2016, Ribeiro et al 2021) and discuss the results obtained for a homogeneous SiO2 film and its respective refractive index under different oxidation conditions.…”