Watt-level, fluoride fiber-based supercontinuum light sources with efficient power distribution in the mid-infrared

Stray light from commercial greenhouses is becoming a significant problem causing disruption to wildlife activity and annoyance for local residents. To quantify the amount of stray light from a typical large greenhouse the authors have modelled several lighting installations based on a range of generic horticultural light sources. The impact of the stray light is dependent on the spectral power distribution of the sources employed, the intensity and distribution. Current standards for obtrusive light from outdoor work places do not seem to be suitable when applied to greenhouses.

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Chaos of interband cascade lasers in the mid-infrared regime

10.21203/rs.3.rs-111694/v1 ◽

2020 ◽

Author(s):

Yu Deng ◽

Zhuo-Fei Fan ◽

Shiyuan Zhao ◽

Frédéric Grillot ◽

Cheng Wang

Keyword(s):

Semiconductor Lasers ◽

Near Infrared ◽

Optical Feedback ◽

Nonlinear Dynamical Systems ◽

Initial Conditions ◽

Electrical Power ◽

High Sensitivity ◽

Light Sources ◽

Mid Infrared ◽

Operation Conditions

Abstract Chaos in nonlinear dynamical systems is featured with irregular appearance and with high sensitivity to initial conditions. Near-infrared semiconductor lasers subject to optical feedback from an external reflector are popular chaotic light sources, which have enabled multiple applications. Here, we report the fully-developed chaos in a mid-infrared interband cascade laser with external optical feedback. The chaos leads to significant electrical power enhancement over a frequency span of 500 MHz. In addition, the laser also exhibits periodic oscillations or low-frequency fluctuations before producing chaos, depending on the operation conditions. This work paves the way for extending chaos investigations from the near-infrared regime to the mid-infrared regime, which can stimulate potential applications in this spectral range.

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High power mid-infrared supercontiuum light sources based on fluorotellurite glass fibers (invited)

Infrared and Laser Engineering ◽

10.3788/irla201847.0803004 ◽

2018 ◽

Vol 47 (8) ◽

pp. 803004

Author(s):

贾志旭 Jia Zhixu ◽

姚传飞 Yao Chuanfei ◽

李真睿 Li Zhenrui ◽

贾世杰 Jia Shijie ◽

赵志鹏 Zhao Zhipeng ◽

...

Keyword(s):

High Power ◽

Glass Fibers ◽

Light Sources ◽

Mid Infrared

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Circadian stimulus – A computation model with photometric and colorimetric quantities

Lighting Research and Technology ◽

10.1177/1477153519887423 ◽

2019 ◽

Vol 52 (6) ◽

pp. 751-762

Author(s):

W Truong ◽

V Trinh ◽

TQ Khanh

Keyword(s):

Power Distribution ◽

Spectral Power ◽

External Validation ◽

Circadian System ◽

Model Fit ◽

Light Sources ◽

Computation Model ◽

Internal Validation ◽

Spectral Power Distribution ◽

Chromaticity Coordinate

The circadian stimulus is an important, validated and updated metric that describes the invisible influences of light on the human circadian system explicitly and scientifically. However, an absolute spectral power distribution must be supplied for its computation, which is only measurable by an expensive and complicated spectrometer. This paper proposes an alternative circadian stimulus computation model that is identified as the function CS(z, Ev) for white light sources based on the most common and simplest parameters of illuminance Ev in lux and the chromaticity coordinate z. These parameters are well known and widely used in both colour science and lighting technology. In order to prove the accuracy and availability of the model, an internal validation was performed with the adapted method repeating split data to check the goodness of the model fit. The fitted model achieved a maximum residual of 0.058 in the circadian stimulus quantity (R2 = 0.998). An external validation with the maximum residual of 0.030 (R2 = 0.999) provided stronger evidence for the usability of the model in applications.

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