Pulsed fluorescence imaging in a light deficient environment is disclosed. A system includes an emitter for emitting pulses of electromagnetic radiation and an image sensor comprising a pixel array for sensing reflected electromagnetic radiation. The system includes a controller configured to synchronize timing of the emitter and the image sensor. The system is such that at least a portion of the pulses of electromagnetic radiation emitted by the emitter comprises electromagnetic radiation having a wavelength from about 770 nm to about 790 nm or from about 795 nm to about 815 nm.

A light radiating portion radiates light with wavelength λ1 having predetermined absorptivity for an object and light with wavelength λ2 having smaller absorptivity for the object than the wavelength λ1, to a target, so as to scan in 2-dimensional directions. A light receiving portion receives scattered lights reflected by the target based on light with wavelength λ1 and light with wavelength λ2. A measuring portion generates information used for detection of the object at the target, based on difference between the two scattered lights with wavelength λ1 and wavelength λ2 received by the light receiving portion. An output portion outputs whether or not the object is present at the target, by 2-dimensional area information, based on scanning by the light radiating portion and information generated by the measuring portion.

An optical system operating in the near or short-wave infrared wavelength range identifies an object based on water absorption. The system comprises a light source with modulated light emitting diodes operating at wavelengths near 1090 and 1440 nanometers, corresponding to lower and higher water absorption. The system further comprises one or more wavelength selective filters and a housing that is further coupled to an electrical circuit and a processor. The detection system comprises photodetectors that are synchronized to the light source, and the detection system receives at least a portion of light reflected from the object. The system is configured to identify the object by comparing the reflected light at the first and second wavelength to generate an output value, and then comparing the output value to a threshold. The optical system may be further coupled to a wearable device or a remote sensing system with a time-of-flight sensor.

A system, wearable device, and method include a light emitter configured to emit light at a first wavelength of between approximately 900 and 1000 nanometers and at a second wavelength of approximately 1350 nanometers, a first light detector spaced at a first distance from the light emitter, and a second light detector spaced at a second distance from the light emitter, the second distance approximately twice the first distance. At least one of hydration and glycogen of muscle tissue is determinable based on a relationship between backscatter light from the muscle tissue as detected by the second light detector and backscatter light from non-muscle tissue as detected by the first light detector.

Methods and apparatus for obtaining a vibrational circular dichroism (VCD) image using a discrete frequency infrared (DFIR) microscope are disclosed. The method includes generating a pulsed laser beam comprising a spectral frequency, which may be tunable; modulating the laser beam to generate circularly polarized light; illuminating a sample and collecting, and detecting an optical signal transmitted or transflected from the location of the sample. The detected signal is demodulated at, for example, both the pulse frequency and the sum or difference of the pulse frequency and the modulating frequency to obtain an intensity value that correspond to the absorbance, and a polarization-dependent value that corresponds to the VCD. Other configurations of the apparatus may be employed to measure VCB and VLD.

A spectroscopic analysis system includes a light source including a light emitting diode (51X), a wavelength converter (52X) configured to convert a wavelength of light output from the light emitting diode (51X), and a condenser (54X) configured to condense light output from the wavelength converter (52X), the light source including a mixing section configured to mix light output from the plurality of light emitting elements, and the wavelength of the light output from the plurality of light emitting elements being different, and a spectroscopic measurement section configured to acquire spectroscopic data by dispersing light reflected from an object on which the light source emits the light.

A surgical access assembly comprises a trocar and a surgical instrument. The trocar comprises a housing and an access tube extending distally from the housing. The housing comprises a hollow light emitter. The housing and the access tube define a lumen extending through the housing and the access tube. The hollow light emitter is configured to project light in the lumen. The surgical instrument comprises an end effector and a shaft extending proximally from the end effector. The shaft comprises an optical receiver positioned within reach of the light from the hollow light emitter. The shaft further comprises a light guide extending from the optical receiver along at least a portion of the shaft toward the end effector.

Described herein are optical sensing devices for photonic integrated circuits (PICs). A PIC may comprise a plurality of waveguides formed in a silicon on insulator (SOI) substrate, and a plurality of heterogeneous lasers, each laser formed from a silicon material of the SOI substrate and to emit an output wavelength comprising an infrared wavelength. Each of these lasers may comprise a resonant cavity included in one of the plurality of waveguides, and a gain material comprising a non-silicon material and adiabatically coupled to the respective waveguide. A light directing element may direct outputs of the plurality of heterogeneous lasers from the PIC towards an object, and one or more detectors may detect light from the plurality of heterogeneous lasers reflected from or transmitted through the object.

Apparatus for determining information associated with reflection characteristics of a surface comprising a sensor (60) configured to generate sensor output dependent on an intensity of light incident on the sensor and having a field of view directed at an external surface (57) in use; an illumination source (58) configured to emit light onto the external surface in use; an optically transparent window (61) located such as to allow light to pass from the illumination source to the external surface and to allow light to pass to the sensor from the external surface in use; a light concentrator (66) fixed to or integral with the window, the light concentrator being configured to concentrate at least some light from the illumination source onto the external surface in use such that the concentrated light may be reflected from the external surface onto the sensor via the window; and a processor (40) configured to use the sensor output to determine information associated with reflection characteristics of the external surface.

The present disclosure relates to a dispersion apparatus. The dispersion apparatus may include an optical substrate; a grating layer on a first side of the optical substrate; and a light outlet layer on a second side of the optical substrate, the second side opposite the first side of the optical substrate. The grating layer is configured to perform dispersion of incident light into first-order diffracted beams having target wavelengths and transmit the first-order diffracted beams into the optical substrate, and wherein a diffraction angle of each of the first-order diffracted beams having the target wavelengths is smaller than a total reflection angle between the optical substrate and air. The light outlet layer is configured to extract the first-order diffracted beams having the target wavelengths in the optical substrate.