The wavelength variable optical filter includes a first substrate, a second substrate, and a bonding film, the bonding film is in contact with a first reflective film and a second reflective film to thus join the first substrate with the second substrate, the bonding film has transparency with respect to light of a predetermined wavelength range, and an optical path extending through the first reflective film, the bonding film, and the second reflective film has transparency with respect to light of the predetermined wavelength range and has no peak of transmittance with respect to a wavelength range measured by the wavelength variable filter.

The disclose provides an optical anti-counterfeiting element and a manufacturing method of the optical anti-counterfeiting element, the optical anti-counterfeiting element includes: a substrate, the substrate has a first surface and a second surface which are opposite to each other; and an interference color layer located on the first surface of the substrate, the interference color layer is located in a non-hollow area of the optical anti-counterfeiting element and is not located in a hollow area, the interference color layer is a Fabry-Perot filter structure, an absorbing layer of the Fabry-Perot filter structure is in contact with the substrate, and a material of the absorbing layer is an alloy.

An optical filter, a spectrometer including the optical filter, and an electronic apparatus including the optical filter are disclosed. The optical filter includes a first reflector including a plurality of first structures that are periodically two-dimensionally arranged, each of the first structures having a ring shape, and a second reflector spaced apart from the first reflector and including a plurality of second structures that are periodically two-dimensionally arranged.

An optical assembly is disclosed including two laterally variable bandpass optical filters stacked at a fixed distance from each other, so that the upstream filter functions as a spatial filter for the downstream filter. The lateral displacement may cause a suppression of the Oblique beam when transmission passbands at impinging locations of the oblique beam onto the upstream and downstream filters do not overlap. A photodetector array may be disposed downstream of the downstream filter. The optical assembly may be coupled via a variety of optical conduits or optical fibers for spectroscopic measurements of a flowing sample.

A color measurement apparatus includes an opening portion forming member that is a member in which an opening portion for causing light arriving from a measurement target to enter inside the apparatus is formed, and that is arranged on a bottom surface at a time of measurement performed by the apparatus, an incident light processing portion that processes light incident through the opening portion, a battery that supplies power to the incident light processing portion, and a first circuit substrate on which a wireless communication portion is mounted, in which in a view from a first direction that is a vertical direction intersecting with the bottom surface and an upper surface which is a surface on an opposite side from the bottom surface, the first circuit substrate and the battery have an overlapping part.

A color measurement apparatus includes an incident light processing portion that processes light incident through the opening portion, a light emission portion that emits light toward the measurement target, a first circuit substrate in which the incident light processing portion is disposed, a second circuit substrate in which the light emission portion is disposed, and a frame assembly that is formed of a metal material, and in which the first circuit substrate and the second circuit substrate are disposed, in which the frame assembly includes a main frame that forms a base of the apparatus, a first subframe that holds the first circuit substrate, and a second subframe that holds the second circuit substrate, and the first subframe and the second subframe are in direct or indirect contact with the main frame.

The present invention proposes an optical band-pass filter with blocked sidebands. The filter comprises a photonic crystal structure based on macroporous silicon having a series of pores defined in the structure. The photonic crystal structure includes a resonator block (BR), comprising at least two periodicity groups (GR1, GR2) between which there is a resonant cavity (CR), wherein the resonant cavity (CR) is adapted to provide a resonance peak in the center of a non-transmitting frequency band of the resonator block (BR); and at least one of a high-pass block (BPA), adapted to block wavelengths below said non-transmitting frequency band; or a low-pass block (BPB), adapted to block wavelengths above said non-transmitting frequency band.

A capacitance detection apparatus is provided with: a parallel circuit in which a first series circuit and a second series circuit are connected in parallel, wherein a tested body and a first resistance element are connected at a first node in the first series circuit, and a reference capacitance element and a second resistance element are connected at a second node in the second series circuit; a power supply circuit configured to apply an alternating current voltage with a specific frequency to the parallel circuit; an inductor element connected between the first node and the second node and configured to increase a phase difference in the voltage with the specific frequency between the first and second nodes; and an output device configured to output an electric signal corresponding to a capacitance of the tested body on the basis of the phase difference.

Described herein is a wavelength reference device comprising a housing defining an internal environment having a known temperature. A broadband optical source is disposed within the housing and configured to emit an optical signal along an optical path. The optical signal has optical power within a wavelength band of interest. An optical etalon is also disposed within the housing and positioned in the optical path to filter the optical signal to define a filtered optical signal that includes one or more reference spectral features having a known wavelength at the known temperature. The device also includes an optical output for outputting the filtered optical signal.

The disclosure provides an optical filter element including a plurality of nano-columns separated from each other in a horizontal direction and extended in a vertical direction, and each of the plurality of nano-columns includes a first material layer having an first extinction coefficient and second material layers having second extinction coefficients different from the first extinction coefficient of the first material layer and a spectrometer including the same.