A metasurface optical device composed of three stacked dielectric layers which form an anti-reflective structure for wavelengths in a predetermined operational wavelength range within the visible spectrum. The anti-reflective structure contains a rectangular lattice of rhombohedral perturbations that produce guided-mode resonances within the predetermined operational wavelength range. The guided-mode-resonant dielectric metasurface device is capable of detecting by colorimetric readout the presence and orientation of a linearly birefringent anisotropic medium, such as a fibrous tissue, positioned above the stacked dielectric layers.

Provided herein is technology relating to sensors for detecting an analyte and particularly, but not exclusively, to liquid crystal sensors, methods of producing liquid crystal sensors, and methods of using liquid crystal sensors.

An example system includes a bulk steering crystal apparatus having a first lens face and a second concave face. The example bulk steering crystal apparatus further includes a number of steering portions interposed between the first lens face and the second concave face, where each of the steering portions includes a bulk substrate portion including an electro-optical material and a corresponding high-side electrode electrically coupled to the corresponding one of the number of steering portions.

An example system includes a bulk steering crystal apparatus having a first lens face and a second concave face. The example bulk steering crystal apparatus further includes a number of steering portions interposed between the first lens face and the second concave face, where each of the steering portions includes a bulk substrate portion including an electro-optical material and a corresponding high-side electrode electrically coupled to the corresponding one of the number of steering portions.

An example system includes a bulk steering crystal apparatus having a first lens face and a second concave face. The example bulk steering crystal apparatus further includes a number of steering portions interposed between the first lens face and the second concave face, where each of the steering portions includes a bulk substrate portion including an electro-optical material and a corresponding high-side electrode electrically coupled to the corresponding one of the number of steering portions.

An example system includes a bulk steering crystal apparatus having a first lens face and a second concave face. The example bulk steering crystal apparatus further includes a number of steering portions interposed between the first lens face and the second concave face, where each of the steering portions includes a bulk substrate portion including an electro-optical material and a corresponding high-side electrode electrically coupled to the corresponding one of the number of steering portions.

An achromatic phase modulator (100) adapted to modulate the phase of an incident beam of light (INCIDENT LIGHT) and to output the thus modulated light, the phase modulator (100) comprising a plurality of liquid crystal elements disposed in series on a light path of the incident light and a control unit (15) comprising a plurality of power sources (14) for applying drive electric signals to the liquid crystal elements, wherein the plurality of liquid crystal elements comprises at least a first and a second liquid crystal element groups (FIRST LIQUID CRYSTAL ELEMENT GROUP; SECOND LIQUID CRYSTAL ELEMENT GROUP), each group being composed of a pair of liquid crystal elements, the liquid crystal elements of the first and second group respectively being made of a first and a second liquid crystal material having a first and a second, different, refractive index wavelength dependence characteristic, the thicknesses (d1/2, d2/2) of the liquid crystal elements forming each group being equal.

A liquid crystal composition, which is a material used for an element for electromagnetic wave signal control in a frequency range of 1 GHz to 10 THz, satisfies at least one of characteristics such as a wide temperature range of a nematic phase and a large refractive index anisotropy and a small dielectric loss tangent (tan ?) in the frequency region used for control, and has an excellent balance of characteristics, and an element containing the composition. A liquid crystal composition including: at least one compound selected from the group consisting of compounds represented by Formula (1). For example, R.sup.1 is C1-12 alkyl; Z.sup.11 is a single bond; L.sup.11, L.sup.12, L.sup.13 and L.sup.18 are hydrogen; L.sup.17 is methyl; Y.sup.11 and Y.sup.22 are hydrogen; and a and c are respectively 0 or 1, b is 1, and a sum of a, b, and c is 2.

##STR00001##

An achromatic phase modulator (100) adapted to modulate the phase of an incident beam of light (INCIDENT LIGHT) and to output the thus modulated light, the phase modulator (100) comprising a plurality of liquid crystal elements disposed in series on a light path of the incident light and a control unit (15) comprising a plurality of power sources (14) for applying drive electric signals to the liquid crystal elements, wherein the plurality of liquid crystal elements comprises at least a first and a second liquid crystal element groups (FIRST LIQUID CRYSTAL ELEMENT GROUP; SECOND LIQUID CRYSTAL ELEMENT GROUP), each group being composed of a pair of liquid crystal elements, the liquid crystal elements of the first and second group respectively being made of a first and a second liquid crystal material having a first and a second, different, refractive index wavelength dependence characteristic, the thicknesses (d1/2, d2/2) of the liquid crystal elements forming each group being equal.

A liquid crystal composition, which is a material used for an element for electromagnetic wave signal control in a frequency range of 1 GHz to 10 THz, satisfies at least one of characteristics such as a wide temperature range of a nematic phase and a large refractive index anisotropy and a small dielectric loss tangent (tan ) in the frequency region used for control, and has an excellent balance of characteristics, and an element containing the composition. A liquid crystal composition including: at least one compound selected from the group consisting of compounds represented by Formula (1). For example, R.sup.1 is C1-12 alkyl; Z.sup.11 is a single bond; L.sup.11, L.sup.12, L.sup.13 and L.sup.18 are hydrogen; L.sup.17 is methyl; Y.sup.11 and Y.sup.22 are hydrogen; and a, b, and c are respectively 0, 1, and 0. ##STR00001##