A colored visibly opaque, highly efficient NIR-transmitting optical filter displaying angle insensitivity is based on one-dimensional photonic crystals. The filter comprises a photonic crystal stack comprising at least one high refractive index layer and two low refractive index layers respectively disposed along a first side and a second side of the high refractive index layer. The photonic crystal stack may have 10 or fewer layers. The filter transmits a first portion of an electromagnetic spectrum having a first range of predetermined wavelengths in an infrared light range or near infrared light range, while reflecting a second portion of the electromagnetic spectrum having a second range of predetermined wavelengths in a visible light range to generate a reflected output. In certain aspects, a refractive index contrast between the at least one high refractive index layer and at least one of the two low refractive index layers is ≥ about 40%.

A device for luminescent imaging includes an array of imaging pixels, a photonic structure over the array of imaging pixels, and an array of features over the photonic structure. A first feature of the array of features is over a first pixel of the array of imaging pixels, and a second feature of the array of features is over the first pixel and spatially displaced from the first feature. A first luminophore is within or over the first feature, and a second luminophore is within or over the second feature. The device includes a radiation source to generate first photons having a first characteristic at a first time, and generate second photons having a second characteristic at a second time. The first pixel selectively receives luminescence emitted by the first and second luminophores responsive to the first photons at the first time and second photons at the second time, respectively.

A method to form a three-dimensional photonic crystal template with a gradient structure involves irradiating a photoresist composition of a thickness of at least 15 μm from at least four laser beams to yield a periodic patterned with a percolating matrix of mass in constructive volumes of a cured photoresist composition and destructive volumes of voids free of condensed matter where the proportion of constructive volume displays a gradient from the irradiated surface to the substrate after development. For a given light intensity, photoinitiator concentration in the photoresist composition, and a given thickness, by irradiating for a relatively short period, a three-dimensional photonic crystal template displaying a gradient having greater constructive volume proximal the air interface forms and a relatively long irradiation period results in a gradient having greater constructive volume proximal the substrate.

A bilayer photonic crystal photoswitch thin-film device having the optical characteristics of both 2D and 3D photonic crystals, and a preparation method thereof are provided. When the bilayer photonic crystal photoswitch thin-film device is rotated periodically, different colors can be observed at a fixed rotation angle, that is, the device has the attribute of changing colors by means of rotation, and can thus realize the opening and closing of an optical path. The bilayer photonic crystal photoswitch thin-film new device has broad application prospects in the fields of photoswitches, optical waveguides, optical prisms, warming signs, anti-counterfeiting and information coding, etc.

A metasurface optical device includes a substrate and a nano-structure layer. The nano-structure layer is arranged on the substrate and includes a plurality of photonic crystal units. Each photonic crystal unit includes a plurality of nano-structure units arranged on the substrate such that an energy bandgap is formed in a cross-section of the photonic crystal unit parallel to the substrate. The energy bandgap surrounds the center area of the cross-section.

Disclosed are a photonic crystal microscope and a method of measuring cellular forces. The photonic crystal substrate includes a photonic crystal substrate, a stage, a probe light source, and an imaging assembly, the photonic crystal substrate being disposed above the stage, the probe light source and the imaging assembly being sequentially disposed at a side of the stage opposite the photonic crystal substrate, the photonic crystal substrate being configured to culture a to-be-measured cell, the photonic crystal substrate being deformable when the to-be-measured cell grows on the photonic crystal substrate; the probe light source is configured to emit probe light to the photonic crystal substrate; the photonic crystal substrate is configured to reflect the probe light to the imaging assembly; the imaging assembly is configured to receive the light reflected from the photonic crystal substrate to perform imaging.

A general purpose sensor architecture integrating a surface enhanced Raman spectroscopy (SERS) substrate, a diffractive laser beam delivery substrate and a diffractive infrared detection substrate is provided that can be used to implement a low-cost, compact lab-on-a-chip biosensor that can meet the needs of large-scale infectious disease testing. The sensor architecture can also be used in any other application in which molecules present in the liquid, gaseous or solid phases need to be characterized reliably, cost-effectively and with minimal intervention by highly skilled personnel.

A device for luminescent imaging includes an array of imaging pixels, a photonic structure over the array of imaging pixels, and an array of features over the photonic structure. A first feature of the array of features is over a first pixel of the array of imaging pixels, and a second feature of the array of features is over the first pixel and spatially displaced from the first feature. A first luminophore is within or over the first feature, and a second luminophore is within or over the second feature. The device includes a radiation source to generate first photons having a first characteristic at a first time, and generate second photons having a second characteristic at a second time. The first pixel selectively receives luminescence emitted by the first and second luminophores responsive to the first photons at the first time and second photons at the second time, respectively.

An optical combiner includes a first layer with a periodic two-dimensional arrangement of structures arranged to support resonance for an input signal of a target wavelength, wherein the structures have a first refractive index. A second layer overlies the structures on the first layer, wherein the second layer includes a second material with a second refractive index, and wherein a difference between the first refractive index and the second refractive index, measured at 587.5 nm, is less than about 1.5. The periodic arrangement of structures is configured such that the optical combiner produces, for the input signal incident on the first layer from air at an oblique elevation angle of greater than about 20°, an output signal with a reflection peak with an average reflection of greater than about 50% within a ± 5° range of the elevation angle.

Apparatus and methods relating to photonic bandgap optical nanostructures are described. Such optical nanostructures may exhibit prohibited photonic bandgaps or allowed photonic bands, and may be used to reject (e.g., block or attenuate) radiation at a first wavelength while allowing transmission of radiation at a second wavelength. Examples of photonic bandgap optical nanostructures includes periodic and quasi-periodic structures, with periodicity or quasi-periodicity in one, two, or three dimensions and structural variations in at least two dimensions. Such photonic bandgap optical nanostructures may be formed in integrated devices that include photodiodes and CMOS circuitry arranged to analyze radiation received by the photodiodes.