An image sensor including a pixel array, the pixel array includes alternately distributed first pixel units and second pixel units, the first pixel unit includes a first radiation sensing element for sensing the radiation in a first wavelength range, and a second radiation sensing element for sensing the radiation in a second wavelength range different from the first wavelength range, in which the first radiation sensing element is separated from the second radiation sensing element, and the second pixel unit includes a third radiation sensing element for sensing the radiation in the third wavelength range, which is different from the first wavelength range and the second wavelength range, and a fourth radiation sensing element for sensing the radiation in the second wavelength range, in which the third radiation sensing element is separated from the fourth radiation sensing element.

A method of monitoring a time-varying fluorescence signal emitted from a fluorescent agent from within a medium with time-varying optical properties is provided that includes providing a measurement data set that includes a plurality of measurement entries that include at least two measurements obtained from a patient before and after administration of the fluorescent agent. The measurements may include one or more of: a DR.sub.ex signal detected by an unfiltered light detector during illumination by excitatory-wavelength light from first region adjacent to the diffuse reflecting medium; a Flr signal detected by a filtered light detector during illumination by excitatory-wavelength light; and a DR.sub.em signal detected by the unfiltered light detector during illumination by emission-wavelength light. The method further includes identifying a post-agent administration portion of the measurement data set; and transforming each Flr signal to an IF signal representing a detected fluorescence intensity emitted solely by the fluorescent agent.

A polarization property image measurement device includes: a first radiation unit that radiates light beams in different polarization conditions onto a target object after subjecting the light beams to intensity modulation at frequencies different from one another; a light receiving unit including first photoelectric conversion units that photoelectrically convert the light beams having been radiated from the first radiation unit and scattered at the target object in correspondence to each of the different polarization conditions, and second photoelectric conversion units that photoelectrically convert visible light from the target object; and a processor that detects signals individually output from the first photoelectric conversion units at the different frequencies and differentiates each signal from other signals so as to determine an origin of the signal as one of the light beams; and creates an image of the target object based upon signals individually output from the second photoelectric conversion units.

A method of monitoring a time-varying fluorescence signal emitted from a fluorescent agent from within a medium with time-varying optical properties is provided that includes providing a measurement data set that includes a plurality of measurement entries that include at least two measurements obtained from a patient before and after administration of the fluorescent agent. The measurements may include one or more of: a DR.sub.ex signal detected by an unfiltered light detector during illumination by excitatory-wavelength light from first region adjacent to the diffuse reflecting medium; a Flr signal detected by a filtered light detector during illumination by excitatory-wavelength light; and a DR.sub.em signal detected by the unfiltered light detector during illumination by emission-wavelength light. The method further includes identifying a post-agent administration portion of the measurement data set; and transforming each Flr signal to an IF signal representing a detected fluorescence intensity emitted solely by the fluorescent agent.

Provided are a filter array, a spectral detector including the filter array, and a spectrometer employing the spectral detector. The filter array may have a multi-array structure including a plurality of filter arrays. The filter array may include a first filter array having a first structure in which a plurality of first filters with different transmittance spectrums are arranged, and a second filter array having a second structure in which a plurality of second filters with different transmittance spectrums are arranged, the second filter array being arranged to at least partially overlap the first filter array at a first position relative to the first filter array so that the multi-arrangement type filter array has a first set of absorbance characteristics. The second filter array may be configurable to be arranged to at least partially overlap the first filter array at a second position relative to the first filter array so that the multi-arrangement type filter array has a second set of absorbance characteristics different from the first set of absorbance characteristics.

Provided is an image pickup apparatus including a multi-band pass filter that selectively transmits band light in a specific band, a color filter that transmits the band light in the specific band per pixel of an image pickup device, the image pickup device that receives light transmitted by the multi-band pass filter and the color filter, and a signal processing section to which a pixel value of the image pickup device is input and which executes a signal process on the pixel value. The multi-band pass filter is configured to selectively transmit band light corresponding to a plurality of color filter elements, and the signal processing section generates a pixel value corresponding to a band, of a pixel to be processed using a raw image base pixel value signal per pixel and a spectral characteristic parameter of the image pickup apparatus.

A method of assessment of renal function by monitoring a time-varying fluorescence signal emitted from a fluorescent agent from within a diffuse reflecting medium with time-varying optical properties is provided that includes using a renal monitoring system comprising at least one light source, at least one light detector, at least one optical filter, and at least one controller to provide a measurement data set comprising a plurality of measurement entries, each measurement data entry comprising at least two measurements obtained at one data acquisition time from a patient before and after administration of the fluorescent agent.

An optical device for sensing a presence of an analyte in a person is provided. The optical device includes a light source, an optical stack, and a reader. The light source emits a first light having a first wavelength. The optical stack is placed on a skin of the person. The optical stack includes a sensor material and an optical filter. The sensor material emits a second light having a second wavelength when irradiated with the first light. An optical property of the second light is sensitive to the presence of the analyte. The optical filter is disposed on the sensor material and includes a plurality of microlayers numbering at least 10 in total. The optical filter has different first and second transmittances at the respective first and second wavelengths.

A device includes a first multi-element image sensor; a second multi-element image sensor; and a polarizing layer positioned between the first and second multi-element image sensors. A portion of light having a first polarization state incident on the device along a first direction is transmitted through the first image sensor, is transmitted through the polarizing layer, and is detected by the second image sensor, and light having a second polarization state orthogonal to the first polarization state incident on the device along the first direction is transmitted through the first image sensor, is blocked by the polarizing layer.

An optical sensor includes a light receiving unit and a calculating unit. The light receiving unit includes a plurality of light receiving elements and a plurality of color filters. The plurality of light receiving elements include a first light receiving element and a second light receiving element through which a photocurrent flows when receiving light. The plurality of color filters include a yellow filter that covers a light receiving surface of the first light receiving element and a red filter that covers a light receiving surface of the second light receiving element. The calculating unit calculates an intensity of a yellow wavelength band based on a difference between a first output signal obtained from the photocurrent of the first light receiving element and a second output signal obtained from the photocurrent of the second light receiving element.