A spectrometer includes an illuminating section; a receiving section configured to detect radiation reflected from an object including an optically inhomogeneous scattering medium; a hardware section configured to obtain a solution of an inverse problem to reconstruct an absorption spectrum of the optically inhomogeneous scattering medium, wherein the illuminating section includes at least one light-emitting diode source, a radiation spectral curve of which is divided, by at least two spectral filters having different spectral transmission curves, into at least two spectral regions, to form an equivalent radiation spectrum from at least two spectral sources, and wherein the hardware section applies the solution of the inverse problem based on information about a spectral content of the radiation of the illuminating section, a signal obtained in a form of a response from the optically inhomogeneous scattering medium, and a spectral sensitivity curve of the receiving section.

Optical computing devices may include capacitance-based nanomaterial detectors. For example, an optical computing device may include a light source that emits electromagnetic radiation into an optical train extending from the light source to a capacitance-based nanomaterial detector; a material positioned in the optical train to optically interact with the electromagnetic radiation and produce optically interacted light; and the capacitance-based nanomaterial detector comprising one or more nano-sized materials configured to have a resonantly-tuned absorption spectrum and being configured to receive the optically interacted light, apply a vector related to the characteristic of interest to the optically interacted light using the resonantly-tuned absorption spectrum, and generate an output signal indicative of the characteristic of interest.

Disclosed are methods of fabricating an integrated computational element for use in an optical computing device. One method includes providing a substrate that has a first surface and a second surface substantially opposite the first surface, depositing multiple optical thin films on the first and second surfaces of the substrate via a thin film deposition process, and thereby generating a multilayer film stack device, cleaving the substrate to produce at least two optical thin film stacks, and securing one or more of the at least two optical thin film stacks to a secondary optical element for use as an integrated computational element (ICE).

A cost effective multicolor sensor and related software achieves a spectral response that closely approximates an ideal photo response to measure optical measurement, for example photosynthetic photo flux density (PPFD). The spectra error of the sensor is smaller than that of the best commercially available sensor at a significantly reduced cost. The sensor may include an 82 array of filtered photodiodes and spectral photo sensors that are linearly combined with the appropriate mathematically determined coefficients to create a corrected spectral response curve that has a spectral error much smaller than the best commercial available sensors made by physical coating methods for the entire desired range.

A lighting unit includes a plurality of light sources that respectively emit plural rays of illumination light. An imaging unit that simultaneously images plural rays of reflected light obtained by the plural rays of illumination light being reflected by a subject so as to obtain information about a plurality of colors, and generates a captured image including the information about the plurality of colors. A memory stores sensitivity information items that correspond to the plurality of light sources respectively. An arithmetic unit performs an arithmetic operation to generate a plurality of separated images from the captured image by using the sensitivity information items. The plurality of separated images correspond to the plurality of light sources respectively, and each of the plurality of separated images only includes information about a corresponding one of the plural rays of reflected light.

A spectrum measurement apparatus includes: a plurality of light sources configured to emit light having different wavelengths to an object; a light detector configured to receive light, which is reflected or scattered from or transmitted through the object, and to measure an intensity of the received light; and a processor configured to determine a strength of an electric signal to be applied to at least one of the plurality of light sources by using one of the plurality of light sources, and by applying the electric signal having the determined strength to the plurality of light sources to obtain a spectrum of the object.

Present invention provides a spectrometer including a first unit spectral filter configured to absorb or reflect light in a part of a wavelength band of a light spectrum of an incident target, a second unit spectral filter configured to absorb or reflect light in a wavelength band different from the part of the wavelength band, a first light detector configured to detect a first light spectrum passing through the first unit spectral filter, a second light detector configured to detect a second light spectrum passing through the second unit spectral filter, and a processing unit configured to perform a function of restoring a light spectrum of the target incident from spectra of light detected from the first light detector and the second light detector.

A monolithic spectrometer (10) for spectrally resolving light (L), comprises a body (2) of solid material having optical surfaces (3,4,5,6a-6c,8) configured to guide the light (L) along an optical path (E1,E2,E3,E4) inside the body (2). The optical surfaces of the body (2) comprise a segmented focusing surface (6a,6b) comprising first and second continuously functional optical shapes (Ca,Cb) to focus received parts of respective beams (La,Lb) onto respective focal position (fa,fb) in an imaging plane (P) outside the body (2). The second continuously functional optical shape (Cb) is separated from the first continuously functional optical shape (Ca) by an optical discontinuity (Dab) there between.

Detection sensitivity of optical computing devices may be improved by utilizing multiple integrated computational elements in combination with one another. Optical computing devices containing multiple integrated computational elements may comprise: two or more integrated computational elements that are identical to one another and optically interact sequentially with incident electromagnetic radiation, such that at least a portion of the photons from the incident electromagnetic radiation optically interacts with each integrated computational element; wherein the sequential optical interaction of the incident electromagnetic radiation with the two or more integrated computational elements increases a detection sensitivity of the optical computing device relative to that obtained when only one of the integrated computational elements is present; and a detector that receives the photons that have optically interacted with each integrated computational element.

An LED lighting based multispectral imaging system for color measurement is provided, including a main control computer and an enclosed type lamp box, where a digital camera is provided at the top of the lamp box, and an LED lamp set control apparatus, a drawer type bearing platform, and an LED lamp set are provided at the bottom of the lamp box. A to-be-measured object is placed on the drawer type bearing platform. The main control computer controls spectral power distribution of the LED lamp set to be in a reciprocal relationship with a spectral sensitivity curve of the digital camera and extracts a camera response and performs calculation, to obtain spectral reflectivity of each pixel of the to-be-measured object.