A method and an apparatus are presented for monitoring a concentration of a specific halogen in a body of water such as a spa or bathing unit for example. The apparatus comprises a housing in which is positioned an optical absorption analyzer for making first and second measurement of transmission of ultraviolet light from a light source emitting light at a specific wavelength. The second and first measurements are taken respectively before and after the ultraviolet light has travelled through a sample of water and are used to derive a concentration of the specific halogen. The derived concentration may then be communicated to a user using a display device and/or may be used to control operational components of a bathing unit for adjusting the concentration of halogen in the water. In some practical implementations, the apparatus may be embodied as a standalone device, which may be configured to float on the water of the bathing unit or, alternatively, may be configured for being installed in-line in a water circulation path of the bathing input by connecting the housing to circulation piping.

Systems and methods disclosed herein provide for detecting gas by: illuminating, with a controllable illuminator system, a scene with light including radiation within the infrared (IR) wavelength range; controlling the illuminator system to emit light at a first wavelength corresponding to a first absorption level of a gas and at a second wavelength corresponding to a second absorption level of a gas, such that an equal amount of radiant energy over a time period is emitted onto the scene for each of said first and second wavelengths; and capturing a first IR image of the scene being illuminated with light at said first wavelength and a second IR image of the scene illuminated with light at said second wavelength, and comparing said first and second IR images to determine whether a characteristic for at least one specific gas is represented in said first and/or second IR images.

A method and an apparatus are presented for monitoring a concentration of a specific halogen in a body of water such as a spa or bathing unit for example. The apparatus comprises a housing in which is positioned an optical absorption analyzer for making first and second measurement of transmission of ultraviolet light from a light source emitting light at a specific wavelength. The second and first measurements are taken respectively before and after the ultraviolet light has travelled through a sample of water and are used to derive a concentration of the specific halogen. The derived concentration may then be communicated to a user using a display device and/or may be used to control operational components of a bathing unit for adjusting the concentration of halogen in the water. In some practical implementations, the apparatus may be embodied as a standalone device, which may be configured to float on the water of the bathing unit or, alternatively, may be configured for being installed in-line in a water circulation path of the bathing input by connecting the housing to circulation piping.

Systems and methods are disclosed to determine the concentration of a species within a sample. An example method may include collecting optical loss data over a range of frequencies from the sample using a spectroscopy system; placing the optical loss data into a plurality of bins, each bin having a defined frequency width; determining an average optical loss data value for the optical loss values within each bin that have an optical loss value less than a threshold value; removing the optical loss data within each bin having a value outside a tolerance range bounding the average optical loss data value for the respective bin; fitting a spectral curve to the remaining optical loss data; and determining the concentration of the species within the sample based on the spectral curve.

A measuring device (1) includes a first signal generation section (3) and a first removal section (5). The first signal generation section (3) generates a first source signal (x1(t)) including a fundamental and a plurality of harmonics based on a first physical quantity (p1) and a second physical quantity (p2). The first removal section (5) removes some or all of the harmonics from the first source signal (x1(t)). The first source signal (x1(t)) is a periodic signal, and one period of the first source signal (x1(t)) includes a first signal (p1), a second signal (p2), and a reference signal (pr). The first signal (p1) has a first duration (w1) and indicates the first physical quantity (p1). The second signal (p2) has a second duration (w2) and indicates the second physical quantity (p2). The reference signal (pr) has a third duration (w3) and indicates the reference physical quantity (pr).

A method and an apparatus are presented for monitoring a concentration of a specific halogen in a body of water such as a spa or bathing unit for example. The apparatus comprises a housing in which is positioned an optical absorption analyzer for making first and second measurement of transmission of ultraviolet light from a light source emitting light at a specific wavelength. The second and first measurements are taken respectively before and after the ultraviolet light has travelled through a sample of water and are used to derive a concentration of the specific halogen. The derived concentration may then be communicated to a user using a display device and/or may be used to control operational components of a bathing unit for adjusting the concentration of halogen in the water. In some practical implementations, the apparatus may be embodied as a standalone device, which may be configured to float on the water of the bathing unit or, alternatively, may be configured for being installed in-line in a water circulation path of the bathing input by connecting the housing to circulation piping.

A color parameter measurement device and a color parameter measurement method are provided. A display light beam from a to-be-tested display panel is split by a beam-splitting assembly into at least testing light beams corresponding to a light-beam-in-first-color filter, a light-beam-in-second-color filter and a light-beam-in-third-color filter respectively. Next, a light-beam-in-first-color component, a light-beam-in-second-color component and a light-beam-in-third-color component of the corresponding testing light beams are transmitted to corresponding receivers through the corresponding filters. Then, the light-beam-in-first-color component, the light-beam-in-second-color component and the light-beam-in-third-color component are converted into electric signals by the corresponding receivers, and then outputted to a processor for color parameter analysis.

A spectroscopy system and method in which the optical path following the interferometer includes a Jacquinot stop having an aperture disposed substantially at its focal point. The Jacquinot stop includes a reflective surface substantially non-orthogonal to the longitudinal axis of the path and facing the source of the IR signal containing an interferogram. The aperture passes an inner portion of the incident IR signal, while the reflective surface reflects an outer portion. The reflected outer portion of the incident IR signal, which contains erroneous spectral information due to inherent flaws in the interferometer optics, is thereby effectively removed from the original incident IR signal ultimately used to irradiate the sample, and yet still be made available for use in monitoring background spectra of the sampling optics.

An on-chip spectroscopic sensor includes a tunable diode laser. A laser driver for drives the tunable diode laser. An analyte test cavity receives a chemical sample and exposes the received chemical sample to light from the tunable diode laser. An optical detector detects light emerging from the analyte test cavity as a result of the laser exposure. A spectral analyzer determines a spectrum of the emerging light, matches and removes one or more known optical fringe patterns from the determined spectrum, and determines a composition or concentration of the chemical sample from the optical fringe pattern-removed spectrum.

The invention relates to a characterization device (50) for characterizing a sample (S) comprising: a memory (MEM) storing a measured spectrum (A.sub.s+p) of said sample, performed through a translucent material, and a measured spectrum of the translucent material (A.sub.p), a processing unit (PU) configured to: determine a spectral energy (E.sub.s+p) of the measured spectrum (A.sub.s+p) of the sample through the translucent material (A.sub.s+p), estimate a coefficient ({circumflex over ()}) from said spectral energy (E.sub.s+p) and, determine a corrected spectrum (.sub.s) of the sample from the measured spectrum (A.sub.s+p) of the sample through the translucent material and from a corrected spectrum of the translucent material (.sub.p),
said corrected spectrum of the translucent material (.sub.p) being determined from the measured spectrum of the translucent material (A.sub.p) and from the estimated coefficient ({circumflex over ()}).