A concentration measurement device including at least one light source; a measurement cell for containing a fluid to be measured; a splitter for dividing light from the light source into incident light being incident into the measurement cell and non-incident light not being incident into the measurement cell; a transmitted-light detector for detecting transmitted light that is the incident light having passed through the measurement cell; a non-incident light detector for detecting the non-incident light; and an arithmetic part for correcting a detection signal of the transmitted-light detector using a detection signal of the non-incident light detector.

A soil mapping system for collecting and mapping soil reflectance data in a field includes an implement having a furrow opener for creating a furrow and an optical module. The optical module is arranged to collect soil reflectance data at a predetermined depth within the furrow as the implement traverses a field. The optical module includes two monochromatic light sources, a window arranged to press against the soil, and a photodiode for receiving light reflected back from the soil through the window. The two light sources have different wavelengths and are modulated at different frequencies. The photodiode provides a modulated voltage output signal that contains reflectance data from both of the light sources. Additional measurement devices are carried by the implement for collecting additional soil property data, such as electrical conductivity, pH, and elevation, which can be used together with the optical data to determine variations in soil organic matter.

An electronic device includes one or more light emitters for emitting light toward an object and one or more light detectors for collecting light exiting the object. A reflective coating, surface, or surface finish can be applied adjacent to the area to which light is emitted and/or through which light exits in order to increase the light collected by the light detector. The reflective coating can be oriented so as to reflect light back into the object.

A method of monitoring a time-varying fluorescence emitted from a fluorescent agent from within a diffuse reflecting medium with time-varying optical properties is disclosed that includes providing at least two measurements obtained from a patient before and after administration of the fluorescent agent that includes an Flr.sub.meas signal detected adjacent to the medium by a filtered light detector during illumination of the medium by excitatory-wavelength light, and at least one DR signal selected from: a DR.sub.ex.sub.meas DR.sub.em, and DR.sub.em,filtered signal. The method further includes identifying a post-equilibration portion of the measurement data set and transforming each Flr.sub.meas signal within the post-equilibration portion of the measurement data set to an IF.sub.agent signal representing a detected fluorescence intensity emitted solely by the fluorescent agent from within the medium. The disclosed method includes removing the effects of leak-through of excitation-level light and removing the effects of autofluorescence from the Flr.sub.meas signal.

An electronic device includes one or more light emitters for emitting light toward an object and one or more light detectors for collecting light exiting the object. A reflective coating, surface, or surface finish can be applied adjacent to the area to which light is emitted and/or through which light exits in order to increase the light collected by the light detector. The reflective coating can be oriented so as to reflect light back into the object.

An optical sensor system may include a light source. The optical sensor system may include a concentrator component proximate to the light source and configured to concentrate light from the light source with respect to a measurement target. The optical sensor system may include a collection component that includes an array of at least two components configured to receive light reflected or transmitted from the measurement target. The optical sensor system may include may a sensor. The optical sensor system may include a filter provided between the collection component and the sensor.

An electronic device includes one or more light emitters for emitting light toward an object and one or more light detectors for collecting light exiting the object. A reflective coating, surface, or surface finish can be applied adjacent to the area to which light is emitted and/or through which light exits in order to increase the light collected by the light detector. The reflective coating can be oriented so as to reflect light back into the object.

A method of monitoring a time-varying fluorescence emitted from a fluorescent agent from within a diffuse reflecting medium with time-varying optical properties is disclosed that includes providing at least two measurements obtained from a patient before and after administration of the fluorescent agent that includes an Flr.sub.meas signal detected adjacent to the medium by a filtered light detector during illumination of the medium by excitatory-wavelength light, and at least one DR signal selected from: a DR.sub.ex.sub.meas DR.sub.em, and DR.sub.em,filtered signal. The method further includes identifying a post-equilibration portion of the measurement data set and transforming each Flr.sub.meas signal within the post-equilibration portion of the measurement data set to an IF.sub.agent signal representing a detected fluorescence intensity emitted solely by the fluorescent agent from within the medium. The disclosed method includes removing the effects of leak-through of excitation-level light and removing the effects of autofluorescence from the Flr.sub.meas signal.

A concentration measurement device including at least one light source; a measurement cell for containing a fluid to be measured; a splitter for dividing light from the light source into incident light being incident into the measurement cell and non-incident light not being incident into the measurement cell; a transmitted-light detector for detecting transmitted light that is the incident light having passed through the measurement cell; a non-incident light detector for detecting the non-incident light; and an arithmetic part for correcting a detection signal of the transmitted-light detector using a detection signal of the non-incident light detector.

A spectrometer system may be used to determine one or more spectra of an object, and the one or more spectra may be associated with one or more attributes of the object that are relevant to the user. While the spectrometer system can take many forms, in many instances the system comprises a spectrometer and a processing device in communication with the spectrometer and with a remote server, wherein the spectrometer is physically integrated with an apparatus. The apparatus may have a function different than that of the spectrometer, such as a consumer appliance or device.