A device such as a stylus may have a color sensor. The color sensor may have a color sensing light detector having a plurality of photodetectors each of which measures light for a different respective color channel. The color sensor may also have a light emitter. The light emitter may have an adjustable light spectrum. The light spectrum may be adjusted during color sensing measurements using information such as ambient light color measurements made with a color ambient light sensor that has a plurality of photodetectors each of which measures light for a different respective color channel. An inertial measurement unit may be used to measure the angular orientation between the stylus and an external object during color measurements. Arrangements in which the light emitter is modulated during color sensing may also be used. Measurements from the stylus may be transmitted wirelessly to external equipment.

A surgical suturing tracking system is disclosed. The surgical suturing tracking system is configured to detect and guide a suturing needle during a surgical suturing procedure. The surgical suturing track system comprises a control circuit configured to predict a path of a needle suturing stroke after receiving an input from a clinician, detect an embedded tissue structure, and assess proximity of the predicted path and the detected embedded tissue structure.

A method for retrieving a corrected spectrum from a measured spectrum (e.g., retrieving a top-of-water spectrum from a measured top-of-atmosphere spectrum) includes creating a scene-specific model of a region of interest and performing a ray-tracing simulation to simulate rays of light that would reach an airborne (or spaceborne) sensor. The region of interest can be an optically complex area such as an inland or coastal body of water. Based on the ray-tracing simulation, a scene-specific correction for unwanted effects (e.g., adjacency effects, variable atmospheric conditions, and/or other suitable effects) is obtained. A corrected spectrum is obtained by correcting the measured spectrum using the scene-specific correction. The ray-tracing simulation may be performed using a graphical processing unit, allowing the scene-specific correction to be performed in real time or near real time.

A system for three-dimensional hyperspectral imaging includes an illumination source configured to illuminate a target object; a dispersive element configured to spectrally separate light received from the target object into different colors; and a light detection and ranging focal plane array (FPA) configured to receive the light from the dispersive element, configured to acquire spatial information regarding the target object in one dimension in the plane of the FPA, configured to acquire spectral information in a second dimension in the plane of the FPA, wherein the second dimension is perpendicular to the first dimension, and configured to obtain information regarding the distance from the FPA to the target object by obtaining times of flight of at least two wavelengths, thereby imaging the target object in three dimensions and acquiring spectral information on at least one 3D point.

A spectrometric device for optical analysis of material composition, coating thickness, surface porosity, and/or other characteristics uses several monochromatic light sources—e.g., laser diodes—to illuminate a sample, with a camera taking an image of the sample under each source's light, and with the various images then being combined to generate a (hyper)spectral image. To address the difficulty in obtaining uniform illumination intensity across the illuminated sample area with solid-state light sources, the output from the light sources may be supplied to an integrating sphere (preferably after being combined within a fiber combiner), and then to a fiber bundle whose output ends are configured as a ring light (a ring of fiber ends directing light at a common spot). The camera may then focus on the spot, at which the sample may be placed for illumination and imaging.

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.

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.

A printer incorporating a spectrometry device includes a spectroscope that includes a light receiving optical system including a light receiver which receives reflected light from a range of measurement in a medium, a distance sensor that detects the distance between the medium and the spectroscope, and a reflecting mirror driver and an optical path adjuster that adjust the optical path of the reflected light which is incident on the light receiving optical system from the range of measurement according to the distance detected by the distance sensor.

A direction-selective interferometric optical filter for spectrometric devices, at least includes an arrangement of two layered one-dimensional photonic structures. Each of the two structures contains a defect layer, and each photonic structure has a dispersion function in the energy momentum space (E, kx, ky), wherein kx and ky are momentum components of transmitted photons of the photonic structures for a defined energy (frequency/wavelength) E in the energy momentum space. Both photonic structures have opposite interfaces which are at a plane-parallel distance from one another. In this case, the dispersion functions of both photonic structures cross or intersect in the energy momentum space and produce a cut set of rays of waves on the surfaces of the dispersion functions at a particular energy, wherein a ray of waves contains waves selectively chosen through the filter at an angle, while other waves are reflected by the filter at other angles.

A spectrometer includes a light source that emits a beam into a sample volume comprising an absorbing medium. Thereafter, at least one detector detects at least a portion of the beam emitted by the light source. It is later determined, based on the detected at least a portion of the beam and by a controller, that a position and/or an angle of the beam should be changed. The beam emitted by the light source is then actively steered by an actuation element under control of the controller. In addition, a concentration of the absorbing media can be quantified or otherwise calculated (using the controller or optionally a different processor that can be local or remote). The actuation element(s) can be coupled to one or more of the light source, a detector or detectors, and a reflector or reflectors intermediate the light source and the detector(s).