Abstract: An image sensor assembly includes at least one upconverter configured to detect light in a NIR waveband that is received from an object to be imaged and generate, based on the detected light, upconverted light that is outside of the NIR waveband; and at least one image sensor configured to detect the upconverted light.

Abstract: An adjustable aperture for an imager includes a mechanical aperture having an opening for permitting light to pass through the mechanical aperture; and an electro-optic shutter having a hole in at least one linearly polarizing layer such that at least a portion of light incident on the electro-optic shutter can pass through the electro-optic shutter regardless of an operating state of the electro-optic shutter, wherein an aperture size of the adjustable aperture is defined by the mechanical aperture when the electro-optic shutter is controlled for light transmission and by the electro-optic shutter when the electro-optic shutter is controlled for light blocking.

Abstract: Methods and systems for facilitating assessment of blood flow in a tissue volume of a subject are disclosed. In some variations, the method may include: after a predetermined amount of a fluorescence agent has been administered to the subject, exciting the fluorescence agent in the tissue volume such that the excited fluorescence agent emits fluorescent light, acquiring fluorescence data based on the fluorescent light emitted during blood flow through the tissue volume, estimating a molar concentration of the fluorescence agent in the blood flowing through the tissue volume, and generating an assessment of blood flow in the tissue volume based at least in part on the fluorescence data and the estimated molar concentration of the fluorescence agent. The estimated molar concentration may be based on the predetermined amount of the fluorescence agent and an estimated circulating blood volume of the subject.

Abstract: Methods and systems for facilitating assessment of blood flow in a tissue volume of a subject are disclosed. In some variations, the method may include: after a predetermined amount of a fluorescence agent has been administered to the subject, exciting the fluorescence agent in the tissue volume such that the excited fluorescence agent emits fluorescent light, acquiring fluorescence data based on the fluorescent light emitted during blood flow through the tissue volume, estimating a molar concentration of the fluorescence agent in the blood flowing through the tissue volume, and generating an assessment of blood flow in the tissue volume based at least in part on the fluorescence data and the estimated molar concentration of the fluorescence agent. The estimated molar concentration may be based on the predetermined amount of the fluorescence agent and an estimated circulating blood volume of the subject.

Abstract: A method and an apparatus for measuring a time-varying change in an amount of blood in a tissue include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain the measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent.

Abstract: An image sensor assembly includes at least one upconverter configured to detect light in a NIR waveband that is received from an object to be imaged and generate, based on the detected light, upconverted light that is outside of the NIR waveband; and at least one image sensor configured to detect the upconverted light.

Abstract: A fluorescence imaging system for imaging an object, the system includes a white light provider that emits white light, an excitation light provider that emits excitation light in a plurality of excitation wavebands for causing the object to emit fluorescent light, a component that directs the white light and excitation light to the object and collects reflected white light and emitted fluorescent light from the object, a filter that blocks light in the excitation wavebands and transmits at least a portion of the reflected white light and fluorescent light, and an image sensor assembly that receives the transmitted reflected white light and the fluorescent light.

Abstract: A first light source with a first etendue generates a first light beam to travel along a first optical path having an expanded portion formed by a collector optical system. A second light source having a second etendue less than one tenth of the first etendue forms second light, which is conducted by a light guide having a distal section with an end face. The second light is emitted from the end face as a second light beam that travels over a second optical path that resides within the expanded portion of the first optical path due to the light guide being disposed relative to the first optical path from an off-axis direction. An optical condenser receives and directs the first and second light beams to a common exit plane to form the combined light beam.

Abstract: A fluorescence imaging system for imaging an object, the system includes a white light provider that emits white light, an excitation light provider that emits excitation light in a plurality of excitation wavebands for causing the object to emit fluorescent light, a component that directs the white light and excitation light to the object and collects reflected white light and emitted fluorescent light from the object, a filter that blocks light in the excitation wavebands and transmits at least a portion of the reflected white light and fluorescent light, and an image sensor assembly that receives the transmitted reflected white light and the fluorescent light.

Abstract: A fluorescence imaging system for imaging an object, the system includes a white light provider that emits white light, an excitation light provider that emits excitation light in a plurality of excitation wavebands for causing the object to emit fluorescent light, a component that directs the white light and excitation light to the object and collects reflected white light and emitted fluorescent light from the object, a filter that blocks light in the excitation wavebands and transmits at least a portion of the reflected white light and fluorescent light, and an image sensor assembly that receives the transmitted reflected white light and the fluorescent light.

Abstract: Methods and systems for facilitating assessment of blood flow in a tissue volume of a subject are disclosed. In some variations, the method may include: after a predetermined amount of a fluorescence agent has been administered to the subject, exciting the fluorescence agent in the tissue volume such that the excited fluorescence agent emits fluorescent light, acquiring fluorescence data based on the fluorescent light emitted during blood flow through the tissue volume, estimating a molar concentration of the fluorescence agent in the blood flowing through the tissue volume, and generating an assessment of blood flow in the tissue volume based at least in part on the fluorescence data and the estimated molar concentration of the fluorescence agent. The estimated molar concentration may be based on the predetermined amount of the fluorescence agent and an estimated circulating blood volume of the subject.

Abstract: A method, an apparatus, and a kit including the apparatus and a fluorescence agent are provided for measuring a time-varying change in an amount of blood in a tissue volume, and include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain a measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent. There is further provided a fluorescence agent for use in the method.

Abstract: Methods and systems for facilitating assessment of blood flow in a tissue volume of a subject are disclosed. In some variations, the method may include: after a predetermined amount of a fluorescence agent has been administered to the subject, exciting the fluorescence agent in the tissue volume such that the excited fluorescence agent emits fluorescent light, acquiring fluorescence data based on the fluorescent light emitted during blood flow through the tissue volume, estimating a molar concentration of the fluorescence agent in the blood flowing through the tissue volume, and generating an assessment of blood flow in the tissue volume based at least in part on the fluorescence data and the estimated molar concentration of the fluorescence agent. The estimated molar concentration may be based on the predetermined amount of the fluorescence agent and an estimated circulating blood volume of the subject.

Abstract: A method, an apparatus, and a kit including the apparatus and a fluorescence agent are provided for measuring a time-varying change in an amount of blood in a tissue volume, and include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain a measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent. There is further provided a fluorescence agent for use in the method.

Abstract: A method and an apparatus for measuring a time-varying change in an amount of blood in a tissue include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain the measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent.

Abstract: A method and an apparatus for measuring a time-varying change in an amount of blood in a tissue include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain the measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent.

Abstract: A method, an apparatus, and a kit including the apparatus and a fluorescence agent are provided for measuring a time-varying change in an amount of blood in a tissue volume, and include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain a measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent. There is further provided a fluorescence agent for use in the method.

Abstract: Methods and systems for facilitating assessment of blood flow in a tissue volume of a subject are disclosed. In some variations, the method may include: after a predetermined amount of a fluorescence agent has been administered to the subject, exciting the fluorescence agent in the tissue volume such that the excited fluorescence agent emits fluorescent light, acquiring fluorescence data based on the fluorescent light emitted during blood flow through the tissue volume, estimating a molar concentration of the fluorescence agent in the blood flowing through the tissue volume, and generating an assessment of blood flow in the tissue volume based at least in part on the fluorescence data and the estimated molar concentration of the fluorescence agent. The estimated molar concentration may be based on the predetermined amount of the fluorescence agent and an estimated circulating blood volume of the subject.

Abstract: A fluorescence imaging system for imaging an object, the system includes a white light provider that emits white light, an excitation light provider that emits excitation light in a plurality of excitation wavebands for causing the object to emit fluorescent light, a component that directs the white light and excitation light to the object and collects reflected white light and emitted fluorescent light from the object, a filter that blocks light in the excitation wavebands and transmits at least a portion of the reflected white light and fluorescent light, and an image sensor assembly that receives the transmitted reflected white light and the fluorescent light.

Abstract: A method and an apparatus for measuring a time-varying change in an amount of blood in a tissue include exciting a fluorescence agent in the blood, acquiring a time-varying light intensity signal during a pulsatile flow of the blood through the tissue volume, the pulsatile flow having a systolic and a diastolic phase resembling a conventional photoplethysmogram, and processing the acquired signal by applying a modified Beer-Lambert law to obtain the measurement of the time-varying change in the amount of blood in the tissue volume. The instantaneous molar concentration of the fluorescence agent is determined by utilizing a concentration-mediated change in a fluorescence emission spectrum of the fluorescence agent.