Abstract: A device and method for measuring a power density distribution of a radiation source is provided. The device includes a radiation source designed to emit a light beam in a radiation direction; a substrate disposed downstream of the radiation source in the radiation direction and having an extent in an x-direction and a y-direction, the substrate having a first region and at least one further second region, and the first region comprises a diffractive structure designed to separate the light beam impinging on the substrate into a zeroth order of diffraction and at least one first order of diffraction; and a detector unit disposed downstream of the substrate in the radiation direction and designed to measure the intensity of the first order of diffraction transmitted through the substrate and to derive a power density distribution therefrom.

Abstract: A lithographic apparatus comprises an illumination system configured to condition a radiation beam, a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam; a substrate table constructed to hold a substrate, a projection system configured to project the patterned radiation beam onto a target portion of the substrate, and a sensor. The sensor (S) comprises a photodiode (2) provided on a face (8) of a semiconductor substrate (4) towards which the radiation beam is directed during operation of the lithographic apparatus, a first radiation blocking material (10) being provided around the photodiode on the face of the semiconductor substrate, and a second radiation blocking material (12) is provided on a side (14) of the semiconductor substrate upon which the radiation beam is incident during operation of the lithographic apparatus.

Abstract: The present invention provides a continuous flowthrough labyrinth device that has a detector well formed therein in which a radiation detection device may be placed. The continuous flowthough labyrinth device allows a fluid sample to be introduced into the flow path of the device so that the fluid sample evenly surrounds the top and side surfaces of the detector well, which results in the fluid sample being evenly distributed around the radiation detection device. The continuous flowthrough labyrinth device may be connected to any radiation level fluid monitoring system, for example systems used by municipalities and/or industries. The continuous flowthrough labyrinth device may be placed such that fluids entering and/or exiting systems are monitored for radiation, or even placed to determine the radiation levels of fluids within systems.

Abstract: Methods of determining the dose of UVC light delivered to a sample comprising a low optical transmission complex fluid are provided. Also provided are methods of inactivation of an organism, such as a spore, a bacteria or a virus, in a sample comprising dose of UVC light delivered to a sample comprising a low optical transmission complex fluid.

Abstract: Traffic monitors based on non-imaging radiation detectors are described. A traffic monitor includes a non-imaging radiation detector that senses spatially patterned radiation emanating from objects moving in a traffic pattern. The detector generates a time varying output signal based on the sensed radiation. Signal processing circuitry is used to analyze the time varying output signal using time domain analysis to provide the traffic information.

Abstract: A reporting system includes a mobile computing device that wirelessly communicates with one or more sensors to track the use of a protective product. Reports are provided on the mobile computing device to remind and motivate a user of the protective product to use it at times most beneficial for receiving the intended protection from it.

Abstract: A sensor housing and cosine diffuser are provided for the detection and measurement of ultraviolet (UV) irradiance. The cosine diffuser has a tiered structure to efficiently receive and transmit incident light that passes over and/or through the sensor housing structure. The sensor housing structure can be configured to have an irregular, serrated, castellated, and or repeating prong and/or tooth sequence to form a cutoff comb, through which incident light is attenuated. The attenuation of light in turn reduces measurement error caused when too much or too little incident light, relative to the actual intensity and irradiance of ambient incident light, reaches and transmits through a cosine diffuser due to the variation of the zenith angle of incident light over the course of a day.

Abstract: A compact synchrotron radiation source includes an electron beam generator, an electron storage ring, one or more wiggler insertion devices disposed along one or more straight sections of the electron storage ring, the one or more wiggler insertion devices including a set of magnetic poles configured to generate a periodic alternating magnetic field suitable for producing synchrotron radiation emitted along the direction of travel of the electrons of the storage ring, wherein the one or more wiggler insertion devices are arranged to provide light to a set of illumination optics of a wafer optical characterization system or a mask optical characterization system, wherein the etendue of a light beam emitted by the one or more wiggler insertion devices is matched to the illumination optics of the at least one of a wafer optical characterization system and the mask optical characterization system.

Abstract: The present invention relates to a method for determining trace amounts of crude oil in water, including the steps of collecting a sample of an oil-containing fluid, adding a toluene extraction volume to the sample, perturbing the sample, dissolving substantially all of the amount of oil in the toluene extraction volume to create a mixed sample, extracting the mixed sample to create an oil-in-toluene layer and an aqueous fluid layer, removing a portion of the oil-in-toluene layer into a dilution container, diluting the portion of the oil-in-toluene layer with a toluene dilution volume to create a dilute sample, measuring an absorption value of the dilute sample using a spectrophotometer, and comparing the absorption value to a calibration curve to quantify the amount of oil in the oil-containing fluid.

Abstract: A method for measuring the concentration of advanced-oxidation active species includes a step of measuring the absorption characteristics of a wavelength region including the wavelength of 195 to 205 nm of a sample and a step of determining the concentration of the advanced-oxidation active species from the aforementioned measured absorption characteristics on the basis of the absorption coefficient of the advanced-oxidation active species in the wavelength region including the wavelength of 195 to 205 nm. The method and the apparatus can measure the concentration of the advanced-oxidation active species directly in line without the need for adding an additive.

Abstract: Described herein is device configured to be a solar-blind UV detector comprising a substrate; a plurality of pixels; a plurality of nanowires in each of the plurality of pixel, wherein the plurality of nanowires extend essentially perpendicularly from the substrate.

Abstract: An illumination optical unit serves for illuminating objects to be examined by a metrology system. The illumination optical unit has an optical pupil shaping assembly for generating a defined distribution of illumination angles of illumination light over an object field in which an object to be examined can be arranged. An optical field shaping assembly for generating a defined intensity distribution of the illumination light over the object field is disposed downstream of the pupil shaping assembly in the beam path of the illumination light. The field shaping assembly has at least one optical field shaping element arranged in the region of a pupil plane of the illumination optical unit. This results in an illumination optical unit which ensures an illumination which can be set in a defined manner with regard to an intensity distribution and an illumination angle distribution over the entire object field.

Abstract: An electromagnetic inspection tool which includes a stage configured to support a wafer having a first surface and an emitter configured to emit electromagnetic waves to be incident on the first surface. The electromagnetic inspection tool further includes a detector configured to detect electromagnetic waves returned from the first surface and a charging mechanism configured to charge the first surface. A method of electromagnetically inspecting a wafer which includes loading a wafer having a first surface onto a stage and emitting electromagnetic waves to be incident on the first surface. The method further includes detecting electromagnetic waves returned from the first surface and charging the first surface prior to detecting the electromagnetic waves returned from the first surface.

Abstract: An optical assembly includes at least one optical semiconductor component which is configured for electroluminescence. The optical semiconductor component is further configured to generate electromagnetic radiation distributed around a radiation maximum. At least one short-pass edge filter is positioned in a beam path of the electromagnetic radiation. A limiting wavelength of the short-pass edge filter is greater than a wavelength of the radiation maximum by a predefined amount.

Abstract: Method for realizing an inspection with short wavelength, high power light source and large numerical aperture, high performance optics to improve defect inspection sensitivity is disclosed. Short wavelength high power laser is realized by using a pulse oscillation type laser suitable for generation of high output power in a short-wavelength region, In addition, a spectral bandwidth of the laser is narrowed down so that amount of chromatic aberration of detection optics with single glass material (i.e. without compensation of chromatic aberration) is lowered to permissible level. Using highly workable glass material to construct the detection optics enables necessary surface accuracy or profile irregularity conditions to be met, even if the number of lenses is increased for large NA or the lens doesn't have a rotationally symmetrical aperture.

Abstract: Field balancing may be performed with an irradiation system including a plurality of adjustable radiant-energy emitters. The irradiation system powers the radiant-energy emitters from a power source and radiant energy is emitted from the radiant-energy emitters, where an amount of radiant energy emitted from each emitter is capable of being varied based on power received from the power source. A plurality of radiant-energy sensors detects an amount of radiant energy which includes radiant energy created directly by at least one of the radiant-energy emitters. The amount of radiant energy detected at at least two of the radiant-energy sensors is compared, and at least one of the radiant-energy emitters is adjusted by varying the power received from the power source so that the amount of radiant energy detected at each of the radiant-energy sensors tends towards becoming approximately equal.

Abstract: The generation of EUV light includes rotating a cylinder at least partially coated with a plasma-forming target material, directing pulsed illumination to a first set of helically-arranged spots traversing a material-coated portion of the rotating cylinder in a first direction and directing pulsed illumination to a second set of helically-arranged spots traversing the material-coated portion of the rotating cylinder in a second direction, the pulsed illumination being suitable for exciting the plasma-forming target material.

Abstract: An extreme ultraviolet (EUV) actinic reticle imaging system suitable for discharge produced plasma (DPP) or laser produced plasma (LPP) reticle imaging systems using a thin film coating spectral purity filter (SPF) positioned on or proximate to the EUV imaging sensor; an EUV imaging sensor carrying this SPF; and methods for making and using the SPF for reticle inspection. The coating may be applied to the imaging sensor in any manner suitable for the particular coating selected. The coating may be composed of a single layer or multiple layers. Typical SPF coating materials include zirconium (Zr) and silicon-zirconium (Si/Zr) in a thickness between 10 nm and 100 nm.

Abstract: A measurement apparatus includes a first light source unit configured to emit a first light having a first wavelength, and a scanning unit configured to move an irradiation position of the first light with respect to a specimen, so as to scan the specimen with the first light. The first light source unit includes a wavelength changing unit configured to change the first wavelength. Movement of the irradiation position is performed by the scanning unit while the wavelength changing unit is changing the first wavelength. A changing cycle of the first wavelength by the wavelength changing unit is shorter than a position moving cycle by the scanning unit.

Abstract: A UV radiation detector with a replaceable secondary window for that is easily replaced by an end user thereby increasing the accuracy of UV radiation measurements. The UV radiation detector with a replaceable secondary window generally includes a housing having a primary window, a UV radiation sensor within the housing to measure UV radiation passing through the primary window, a secondary window protecting the primary window from the fluid and a retainer member having an outer opening removably connectable to the housing to retain the secondary window. The secondary window can be easily replaced after becoming contaminated.

Abstract: According to one embodiment, an optimum imaging position detecting method includes acquiring an image of a predetermined area of a substrate surface, calculating, on the basis of the image of the predetermined area, peak intensity corresponding to a value obtained by subtracting average signal intensity of an area outside an intensity acquisition part from signal intensity of the intensity acquisition part, calculating variation of the peak intensity, executing acquiring the image of the predetermined area, calculating the peak intensity, and calculating the variation of the peak intensity at each of a plurality of imaging positions, and determining that a position of the maximum variation of the peak intensity is an optimum imaging position.

Abstract: Eyewear having radiation monitoring capability is disclosed. Radiation, such as ultraviolet (UV) radiation, infrared (IR) radiation or light, can be measured by a detector. The measured radiation can then be used in providing radiation-related information to a user of the eyewear. Advantageously, the user of the eyewear is able to easily monitor their exposure to radiation.

Abstract: Provided herein are ultraviolet (UV) devices, systems, and methods for UV disinfection and sterilization, more specifically, UV devices, systems, and methods for UV disinfection and sterilization of a container, room, space or defined environment. The systems, UV devices, and methods are particularly useful for the UV disinfection and sterilization of a container used in the food and dairy industry and for containers used in the process of fermentation for an alcoholic beverage. Provided are also UV devices, systems, and methods for inhibiting the growth of one or more species of microorganisms present in a container, room, space or defined environment, preferably for inhibiting the growth of one or more species of microorganisms present on an interior surface of a container, room, space or defined environment.

Abstract: Improved analytical, diagnostic, monitoring, and other methods (and their associated devices) for evaluating the extent of deposition of an agent onto a substrate are described. Exemplary methods may be used in the in the monitoring of the dental health of patients or in the fast, efficient screening and/or characterization of formulations in terms of their use for depositing oral actives onto tooth surfaces. The methods involve the direct or in situ analysis of substrates, onto which agents are deposited, using Near-IR spectroscopy and/or UV spectroscopy.

Abstract: A system for authenticating a document includes a document having a substrate comprising an optical brightener; printing a background with a ultraviolet (UV) absorbing material on the substrate comprising a first pattern of lines having a first frequency and a first orientation; printing a security mark with the UV material on the substrate comprising a second pattern of lines having a second frequency and a second orientation; a lenticular lens; placing the lenticular lens over the security mark and background; a UV lamp; illuminating the security mark and background through the lenticular lens with UV light; orienting the lenticular lens to match either the first orientation or the second orientation; and authenticating the document if the security mark matches a predetermined security mark.

Abstract: A disinfection device includes a disinfection chamber into which a radiation source emits ultraviolet-C (UV-C) radiation. A radiation sensor detects the amount of UV-C radiation within the disinfection chamber, and a temperature sensor produces temperature values of a temperature within the disinfection chamber. A processing unit generates accumulated UV-C radiation values and verifies that the accumulated UV-C radiation value in the disinfection chamber reaches a first radiation threshold while also verifying that the temperature in the disinfection chamber stays below a first temperature threshold. The UV-C radiation may be emitted into the disinfection chamber over one or more fixed periods of time while the total time for the disinfection process is limited to a primary time interval. The process may terminate successfully if the first radiation threshold is exceeded before the primary time interval expires.

Abstract: Systems and methods are provided for analyzing conditions associated with a physical feature using digital images. The method comprises acquiring a white-light image and an ultraviolet (“UV”) image of at least a portion of a body surface, such as a person's face, each of the white-light and UV images including a plurality of pixels and each pixel in the UV image corresponding to a respective pixel in the white-light image. The method further comprises identifying feature pixels in the white-light and UV images, and obtaining results associated with at least one physical condition using information in the feature pixels in the first white light and UV images.

Abstract: A system and method for monitoring a fiber curing system is disclosed. In one example, transmittance of a curing tube is determined so that curing of a coating applied to a fiber may be more uniform.

Abstract: A system and method for monitoring and operating one or more light emitting devices is disclosed. In one example, light intensity within a dual elliptical reflecting chamber is sensed and operation of a fiber curing system is adjusted in response to an amount of sensed light energy.

Abstract: The invention relates to a water treatment using an UV AOP. The invention combines an UV AOP (11) applied to a water containing a free chlorine species (8) with a chemical post treatment (14), a quenching. The quenching (14) is applied to said water (9) after the UV AOP (11) able to reduce a remaining content of said free chlorine species in said water (9).

Abstract: A method for inspecting a spatial light modulator includes: performing such control that in an inspection target area in an array of mirror elements, the mirror elements in a first state in which incident light is given a phase change amount of 0 and the mirror elements in a second state in which incident light is given a phase change amount of 180° (?) become arrayed in a checkered pattern; guiding light having passed the inspection target area to a projection optical system with a resolution limit coarser than a width of an image of one mirror element, to form a spatial image; and inspecting a characteristic of the spatial light modulator from the spatial image. This method allows us to readily perform the inspection of the characteristic of the spatial light modulator having the array of optical elements.

Abstract: Described herein are embodiments of a method to control energy dose output from a laser-produced plasma extreme ultraviolet light system by adjusting timing of fired laser beam pulses. During stroboscopic firing, pulses are timed to lase droplets until a dose target of EUV has been achieved. Once accumulated EUV reaches the dose target, pulses are timed so as to not lase droplets during the remainder of the packet, and thereby prevent additional EUV light generation during those portions of the packet. In a continuous burst mode, pulses are timed to irradiate droplets until accumulated burst error meets or exceeds a threshold burst error. If accumulated burst error meets or exceeds the threshold burst error, a next pulse is timed to not irradiate a next droplet. Thus, the embodiments described herein manipulate pulse timing to obtain a constant desired dose target that can more precisely match downstream dosing requirements.

Abstract: Described herein are embodiments of a method to control energy dose output from a laser-produced plasma extreme ultraviolet light system by adjusting timing of fired laser beam pulses. During stroboscopic firing, pulses are timed to lase droplets until a dose target of EUV has been achieved. Once accumulated EUV reaches the dose target, pulses are timed so as to not lase droplets during the remainder of the packet, and thereby prevent additional EUV light generation during those portions of the packet. In a continuous burst mode, pulses are timed to irradiate droplets until accumulated burst error meets or exceeds a threshold burst error. If accumulated burst error meets or exceeds the threshold burst error, a next pulse is timed to not irradiate a next droplet. Thus, the embodiments described herein manipulate pulse timing to obtain a constant desired dose target that can more precisely match downstream dosing requirements.

Abstract: Some aspects of the invention may be related to an ultraviolet (UV) water disinfection system and a method of assembling such system. The system may be designed to treat, inactivate, disintegrate and/or remove at least two predetermined different types of contaminations. The system may include a chamber to carry the water containing the predetermined types of contaminations. The system may further include one or more first-type UV lamps having a first UV emission spectrum and one or more second-type UV lamps having a second UV emission spectrum different than the first spectrum. A location of the one or more first-type UV lamps and the one or more second-type UV lamps may be determined such that a combined UV impact function matches with a combined sensitivity response function of the two or more predetermined different types of contaminations in the water each having a different response function.

Abstract: A lithographic apparatus comprising a support structure constructed to support a patterning device, the patterning device being capable of imparting an EUV radiation beam with a grating in its cross-section to form a patterned EUV radiation beam, and a projection system configured to project the patterned EUV radiation beam onto a target portion of the substrate, wherein the support structure is provided with a grating comprising a series of first reflective portions which alternates with a series of second reflective portions, the second reflective portions having a reflectivity which is less than the reflectivity of at least part of the first reflective portions and which is greater than zero.

Abstract: A system and method are disclosed for detecting open flames in an outdoor environment. Structurally, the outdoor flame detector includes both an ultra-violet (UV) detector and a Radio Frequency (RF) detector. While operating within predetermined parameters, these detectors respectively create an event signal(s) and a cancel signal(s). In detail, the UV detector will output an event signal whenever UV radiation with a fluence above a predetermined value is incident on the UV detector. On the other hand, the RF detector will output a cancel signal whenever it receives an RF component transmitted in an electrical arc discharge having an intensity above a predetermined threshold. The event signal and the cancel signal are then individually and collectively evaluated by a computer to distinguish between an actual open flame and a non-flame event, such as an electric arc discharge (e.g. lightening, electric motors and arc welding).

Abstract: Improved analytical, diagnostic, monitoring, and other methods (and their associated devices) for evaluating the extent of deposition of an agent onto a substrate are described. Exemplary methods may be used in the in the monitoring of the dental health of patients or in the fast, efficient screening and/or characterization of formulations in terms of their use for depositing oral actives onto tooth surfaces. The methods involve the direct or in situ analysis of substrates, onto which agents are deposited, using Near-IR spectroscopy and/or UV spectroscopy.

Abstract: The passivation of a nonlinear optical crystal for use in an inspection tool includes growing a nonlinear optical crystal in the presence of at least one of fluorine, a fluoride ion and a fluoride-containing compound, mechanically preparing the nonlinear optical crystal, performing an annealing process on the nonlinear optical crystal and exposing the nonlinear optical crystal to a hydrogen-containing or deuterium-containing passivating gas.

Abstract: One embodiment relates to an oblique illuminator. The oblique illuminator includes a light source emitting a light beam, a first reflective surface, and a second reflective surface. The first reflective surface has a convex cylindrical shape with a projected parabolic profile along the non-powered direction which is configured to reflect the light beam from the light source and which defines a focal line. The second reflective surface has a concave cylindrical shape with a projected elliptical profile which is configured to reflect the light beam from the first reflective surface and which defines first and second focal lines. The focal line of the first reflective surface is coincident with the first focal line of the second reflective surface. The first and second focal lines of the second reflective surface may be a same line in which case the elliptical curvature is a projected spherical profile. Other embodiments, aspects and features are also disclosed.

Abstract: The need for an instant handheld analysis of cannabis products has been in demand for years from the consumer/dispensary level and grower's quality control. Recent developments in sensitivity and detection devices have transformed the bulky tabletop industry into a personal measurement device. This device consists of a sample cell slot that is an opening used to insert the sealed, extracted, sample cell (see FIG. 1). The extraction cell (see FIG. 2) is a Borosillate material that opens at the top to allow small size sample to be inserted, and mixed into a small amount of solvent. The extracted solvent is then transferred to a polyethylene sample cell (see FIG. 3) and inserted into the device. Once the sample cell is inserted in the device, the user presses the “Measure” button and the THC concentration is shown on the display after a number of seconds.

Abstract: A beam regulating apparatus for an EUV illumination beam has a position sensor device and a control/regulating device, which is signal-connected to the position sensor device. Furthermore, at least one beam regulating component which influences the beam path of the illumination beam is signal-connected to the control/regulating device. The position sensor device has at least one diffraction grating for generating at least two reference partial beams from the illumination beam. Furthermore, the position sensor device has a respective position sensor assigned to one of the reference partial beams, for detecting the assigned reference partial beam. This results in a beam regulating apparatus which enables well-controllable illumination in conjunction with a simple construction.

Abstract: A regenerative ring resonator in the path of a light beam includes a discharge chamber having electrodes and a gain medium between the electrodes; an optical coupler that is partially reflective so that at least a portion of a light beam impinging on the optical coupler from the discharge chamber is reflected back through the discharge chamber and at least a portion of the light beam impinging on the optical coupler from the discharge chamber is transmitted through the optical coupler; and an attenuation optical system in the path of the light beam within the resonator, the attenuation optical system having a plurality of distinct attenuation states, with each attenuation state defining a distinct attenuation factor applied to the light beam to provide adjustment of an energy of the light beam.

Abstract: The photodetector device includes a semiconductor body having a front surface, and an active-area region that extends in the semiconductor body facing the front surface and is configured for receiving a light radiation and generating, in response to the light radiation received, electric charge carriers. A polydimethylsiloxane cover layer extends on the front surface in the active-area region so that the light radiation is received by the active-area region through the cover layer.

Abstract: The invention relates to extreme ultraviolet “EUV” radiation generating systems that include a vacuum chamber where a target material can be positioned at a target position for generation of EUV radiation, and a beam guiding chamber for guiding a laser beam from a driver laser device towards the target position. The EUV radiation generating apparatus includes an intermediate chamber which is arranged between the vacuum chamber and the beam guiding chamber, a first window which seals the intermediate chamber in a gas-tight manner for entry of the laser beam from the beam guiding chamber and a second window which seals the intermediate chamber in a gas-tight manner for exit of the laser beam into the vacuum chamber. The invention also relates to a method for operating the EUV radiation generating apparatus.

Abstract: An extreme ultraviolet light source device, comprising a collector mirror focusing extreme ultraviolet radiation at a focal point, wherein a porous plate having a plurality of through holes arranged such that only radiation focusing at said focal point passes is provided insertably between said collector mirror and said focal point on an optical axis of said collector mirror, and a detection means is provided to receive radiation having passed through said porous plate and to detect an intensity of said received radiation, and a method for detecting an irradiance distribution in an extreme ultraviolet light source device.

Abstract: An apparatus and a method to detect a defect or particle on a surface that involves combining an object radiation beam redirected by the surface with a reference radiation beam having a plurality of intensities lower than the object radiation beam, to produce a plurality of patterns detected by a detector in order to detect the defect or particle on the surface from the patterns.

Abstract: The inventive concept provides apparatuses and methods for monitoring semiconductor fabrication processes in real time using polarized light. In some embodiments, the apparatus comprises a light source configured to generate light, a beam splitter configured to reflect the light toward the wafer being processed, an objective polarizer configured to polarize the light reflected toward the wafer and to allow light reflected by the wafer to pass therethrough, a blaze grating configured to separate light reflected by the wafer according to wavelength, an array detector configured to detect the separated light and an analyzer to analyze the three-dimensional profile of the structure/pattern being formed in the wafer.

Abstract: An apparatus for inspecting a photomask, comprising an illumination source for generating a light which illuminates a target substrate, objective optics for receiving and projecting the light which is reflected from the target substrate, the objective optics includes a first mirror arranged to receive and reflect the light which is reflected from the target substrate, a second mirror which is arranged to receive and reflect the light which is reflected by the first mirror, a third mirror which is arranged to receive and reflect the light which is reflected by the second mirror, and a segmented mirror which is arranged to receive and reflect the light which is reflected by the third mirror. The segmented mirror includes at least two mirror segments. The apparatus further includes at least one sensor for detecting the light which is projected by the objective optics.

Abstract: A highly efficient vacuum ultraviolet circular dichroism spectrometer is provided; the spectrometer suitable for laboratory use or for integration into a beam line at a synchrotron radiation facility. In one embodiment, a spectroscopic circular dichroism instrument is provided; the instrument configured so as to enable circular dichroism data to be simultaneously obtained for multiple wavelengths of light. The instrument may be further configured to operate in at least a portion of the vacuum ultraviolet wavelength region.

Abstract: A system for measuring a characteristic of a solar cell is disclosed and includes a light source irradiating an optical signal having a spectral range from about 100 nm to about 3000 nm, a wavelength selector configured to selectively narrow the spectral range of the optical signal, a beam splitter, a reference detector in optical communication with the beam splitter and configured to measure a characteristic of the optical signal, a specimen irradiated with the optical signal, a reflectance detector in optical communication with the specimen via the beam splitter and configured to measure an optical characteristic of the optical signal reflected by the specimen, a multiplexer in communication with at least one of the reference detector, specimen, and reflectance detector, and a processor in communication with at least one of the reference detector, specimen, and reflectance detector via the multiplexer and configured to calculate at least one characteristic of the specimen.