A photodiode includes semiconductor layers and a gate insulating layer provided on a buried insulating layer formed on a substrate and has a diffraction grating portion in which a plurality of groove portions are formed in a two-dimensional lattice shape, on the gate insulating layer. Measurement light is guided by an optical system including a photoelastic modulator and is incident on the photodiode. The measurement light is emitted from the light source device in a state of being linearly polarized light having a predetermined wavelength and is converted at a predetermined frequency by the optical system such that states in which the measurement light becomes linearly polarized light beams of two orthogonal directions are repeated. In addition, electric signals from the photodiode in the state in which the measurement light becomes the linearly polarized light beams of the two orthogonal directions are lock-in detected.

An apparatus and a method for correctly measuring a phase of an extreme ultraviolet (EUV) mask and a method of fabricating an EUV mask including the method are described. The apparatus for measuring the phase of the EUV mask includes an EUV light source configured to generate and output EUV light, at least one mirror configured to reflect the EUV light as reflected EUV light incident on an EUV mask to be measured, a mask stage on which the EUV mask is arranged, a detector configured to receive the EUV light reflected from the EUV mask, to obtain a two-dimensional (2D) image, and to measure reflectivity and diffraction efficiency of the EUV mask, and a processor configured to determine a phase of the EUV mask by using the reflectivity and diffraction efficiency of the EUV mask.

An apparatus and a method for correctly measuring a phase of an extreme ultraviolet (EUV) mask and a method of fabricating an EUV mask including the method are described. The apparatus for measuring the phase of the EUV mask includes an EUV light source configured to generate and output EUV light, at least one mirror configured to reflect the EUV light as reflected EUV light incident on an EUV mask to be measured, a mask stage on which the EUV mask is arranged, a detector configured to receive the EUV light reflected from the EUV mask, to obtain a two-dimensional (2D) image, and to measure reflectivity and diffraction efficiency of the EUV mask, and a processor configured to determine a phase of the EUV mask by using the reflectivity and diffraction efficiency of the EUV mask.

The present invention includes a prism having a light incidence surface and a film formation surface, a metal film disposed on the film formation surface, and a trapping body secured to the metal film. Excitation light is irradiated from an excitation light irradiation part onto an analysis chip installed in a chip holder, and excitation light reflected by the analysis chip is detected. The information outputted by the excitation light irradiation part is acquired.

The present invention includes a prism having a light incidence surface and a film formation surface, a metal film disposed on the film formation surface, and a trapping body secured to the metal film. Excitation light is irradiated from an excitation light irradiation part onto an analysis chip installed in a chip holder, and excitation light reflected by the analysis chip is detected. The information outputted by the excitation light irradiation part is acquired.

An apparatus for detecting one or more properties of a downhole fluid includes a housing. The apparatus also includes a location-sensitive optical detector, arranged within a chamber formed by the housing. The apparatus further includes a light source, arranged within the chamber. The apparatus also includes a lens, positioned at an end of the housing, the lens preferably having a flat side and a curved side, the flat side positioned proximate the chamber to position the flat side closer to the light source than the curved side. The apparatus further includes a mirror, arranged outside the housing.

A method for adjusting a focus of an optical system includes focusing measurement light in a sample space using an optical arrangement. The measurement light is transmitted on a sample side of the optical arrangement through at least one optical medium. The measurement light reflected by a reflector and transmitted through a further optical arrangement is detected using a detector arrangement. A working distance between the optical arrangement and the reflector is ascertained based on the measurement light detected by the detector, wherein a focus of the measurement light lies on the reflector for the working distance.

A solution is provided comprising boron nitride nanotubes (BNNTs) in a liquid solvent. An optical waveguide, such as an optical fiber, is contacted with the solution so as to form a layer of the solution supported on at least a portion of the optical waveguide. The liquid solvent is then removed from the layer of the solution supported on the optical waveguide in order to form a coating of the BNNTs on the optical waveguide. Further provided is a BNNT coated optical waveguide for use as a sensor.

A solution is provided comprising boron nitride nanotubes (BNNTs) in a liquid solvent. An optical waveguide, such as an optical fiber, is contacted with the solution so as to form a layer of the solution supported on at least a portion of the optical waveguide. The liquid solvent is then removed from the layer of the solution supported on the optical waveguide in order to form a coating of the BNNTs on the optical waveguide. Further provided is a BNNT coated optical waveguide for use as a sensor.

An optical sensor includes: a sensor portion, having a transmitter and at least one receiver, configured to couple to a wettable component having a fluid flow channel, wherein the transmitter is disposed to emit a light that travels from the sensor portion to the wettable component where a majority of the light is directed towards the fluid flow channel at an angle between a first critical angle and a second critical angle; wherein with liquid filling the fluid flow channel, the majority of the light refracts at a liquid interface and travels through the entirety of the fluid flow channel; wherein with gas in the fluid flow channel, the majority of the light reflects at a gas interface and does not travel through the entirety of the fluid flow channel; wherein the amount of the light refracted and/or reflected and received by the at least one receiver, is used to determine if there is liquid or gas in the fluid flow channel.