Multi-layered all-dielectric grating visible color filter with a narrow band and high-quality factor

Abstract

In this paper, we proposed a double-layer all-dielectric grating. Under the premise of ensuring the strength of the resonance peak, the upper SiO2 grating layer suppresses the tendency of high-order dipole resonance excitation and improves the transmittance at the non-resonant position (T > 99%). The distribution of chromaticity coordinates on the CIE 1931 chromaticity diagram also proves that suppressing side peaks can effectively increase the saturation of structural colors, which is essential for a high precision imaging system. The cyclic displacement current excites the magnetic dipole resonance, which causes the magnetic field to be confined in the high refractive index material HfO2 grating layer. By adjusting the duty cycle of the grating structure, a reflection spectrum with low full width half maximum (FWHM) (∼2 nm) and high-quality factor Q (∼424.5 nm) can be obtained. And the spectral intensity is more sensitive to the polarization angle. This work is of great significance to the development of sensors, display imaging and other fields. At the same time, the material of the grating filter meets the requirements of high damage threshold of the high-power laser system, and its high-power laser application potential is inestimable.

Ultra-Narrowband High-Transmissivity Guided-Mode Resonance Filter Based on Dual Dielectric Film Structure and High Refractive Index Waveguide Layer

“…Compared to multispectral imaging, high spectral imaging offers higher spectral resolution, enabling the capture of hundreds to thousands of spectral channels in the target wavelength range, thus acquiring continuous spectral information. Despite the growing demand for transmissive filters in the visible range [9], [10], [11], [12], [13], most studies have focused on reflection filters in the infrared band [14], [15], [16], [17], [18], [19]. Existing transmission filters in the visible range suffer from limitations including low diffraction efficiency, wide FWHM, and high sidebands, which lead to structural color issues such as reduced saturation and accuracy of color resolution.…”

Polarization Insensitivity Research of the Three-layer Silicon-based Symmetric Cascade Optical Sensor

“…GMR is more likely to occur in subwavelength grating structures [6][7][8], where the grating period is significantly smaller than the incident light wavelength. Such structures exhibit high diffraction efficiency and narrow bandwidth properties, making them suitable for designing narrow-band filters [9][10][11][12][13], optical modulators [14][15][16][17][18], and sensors [19][20][21][22].…”

A Method of Improving the Structural Color Quality of HfO2 Grating Based on Thin Film Filter

“…High-refractive-index dielectric (Si, Si 3 N 4 , TiO 2 , etc.) metasurface structures based on Mie resonances, such as nano-blocks [25][26][27], disks [24,28], and gratings [29,30], have been demonstrated to yield high-purity structural colors. However, due to the influence of higher-order Mie resonances, it is difficult to obtain highly saturated structural colors with this metasurface color filter.…”

“…Based on Mie resonance mechanism of high refractive index dielectric materials, we obtained low full width of half maximum transmission (FWHM) (~2 nm) and highquality factor Q (~424.5 nm) excellent characteristics after changing the duty cycle. It is of great significance for the application of sensors [30]. To find a low-cost and efficient means of inhibition will further expand its application areas.…”