Lensless dual-color fluorescence imaging device using hybrid filter

In this study, a dual-band hybrid filter that achieves high excitation light rejection performance in a lensless imaging system was fabricated and incorporated into an imaging device. The hybrid filter consisted of interference and absorption filters, and a fiber optic plate. The interference filters were attached to both sides of the fiber optic plate, which was placed on top of the absorption filter to suppress the decrease in spatial resolution. In addition, the lamination order was optimized to achieve a high fluorescence observation performance. The fabricated hybrid filter was mounted on an image sensor and had the ability to indicate the green and red fluorescence components.

High-performance Tunable Multichannel Absorbers Couple with Graphene-based Grating and Dual-Tamm Plasmonic Structures

We present a hybrid Tamm system targeting the tunable multichannel absorber. The proposed optical absorber is analyzed and investigated by using the transfer matrix method (TMM). The numerical and theoretical studies show that the four perfect absorption peaks are generated by two types of resonant modes excited in the structure, which can be reasonably explained by the guide-mode resonance (GMR) and optical Tamm state (OTS). More importantly, the strong interaction between the two modes gives rise to mode hybridization by adjusting the grating period. Furthermore, the active modulation of the GMR-based peak can be manipulated discretely by tuning the polarization angle or continuously by changing the chemical potential of graphene. The presented optical absorption filter will meet high level of effectiveness in developing high-performance optoelectronic devices.

Dual-Wavelength High-Spectral-Resolution Lidar for Profiling Optical Properties of Aerosol and Cloud

A dual-wavelength high-spectral-resolution lidar (HSRL) based on an iodine absorption filter and a field-widened Michelson interferometer (FWMI) has been developed to profile backscatter and extinction coefficients of aerosols and clouds accurately. This instrument was tested and calibrated on multiple observations in Hangzhou and Zhoushan, respectively, from August 2018 to April 2019. This paper discusses the design and the internal calibration method of the lidar system in detail, with several typical cases of observations and the analysis of these data products. The optical properties of urban aerosols in Hangzhou and the evolvement of clouds in Zhoushan are presented, respectively.