Patent classifications
G03H2001/0447
Methods and apparatus for imaging with multimode optical fibers
A multimode waveguide illuminator and imager relies on a wave front shaping system that acts to compensate for modal scrambling and light dispersion by the multimode waveguide. A first step consists of calibrating the multimode waveguide and a second step consists in projecting a specific pattern on the wave
guide proximal end in order to produce the desire light pattern at its distal end. The illumination pattern can be scanned or changed dynamically only by chang
ing the phase pattern projected at the proximal end of the waveguide. The third and last step consists in collecting the optical information, generated by the sample, through the same waveguide in order to form an image. Known free space microscopy technique can be adapted to endoscopy with multimode waveguide, such as, but not limited to, fluorescence imaging or Raman spectros
copy or imaging, 3D linear scattering imaging or two-photon imaging. Super-resolution, i.e., resolution below the diffraction limit, is achieved for example but not limited to, using the STimulated Emission Depletion microscopy (STED) technique or the Structured Illumination Microscopy (SIM) technique or a stochastic illumination based method (PALM, STORM) in combination with the multimode waveguide imaging method.
COHERENCE ADJUSTABLE DIGITAL HOLOGRAPHY SYSTEM
Disclosed is a coherence-adjustable digital holography system. More particularly, the coherence-adjustable digital holography system includes a light source part for generating low-interference light; a dispersion part for dispersing the generated light, an adjustment part for adjusting coherence by adjusting a spectrum bandwidth of the light which has passed through the dispersion part; and a detection part for detecting a holographic image of a subject from the adjusted light. In accordance with such a configuration, an interference fringe may be easily obtained through coherence adjustment, whereby the accuracy of a detected holographic image may be improved.
OBSERVATION DEVICE AND OBSERVATION METHOD
An observation apparatus includes a light source, a beam splitter, a mirror, a mirror, a cylindrical lens, a lens, a cylindrical lens, a beam splitter, a lens, a frequency shifter, an imaging unit, and an analysis unit. The analysis unit generates a complex amplitude image of each of a plurality of light irradiation directions of object light based on time series data of an interference intensity image output from the imaging unit, and generates a three-dimensional complex differential interference image of an observation object based on the complex amplitude image of each of the plurality of light irradiation directions. The analysis unit obtains a three-dimensional phase image of the observation object based on the three-dimensional complex differential interference image.
AN IN SITU HOLOGRAPHIC IMAGING SYSTEM FOR MARINE STUDIES
The invention improves holographic imaging systems by being modular with deployment in a lens-less configuration or with a microscope objective, leading to a resolution range of 5.5 and to 0.5 m/pixel, respectively, and resulting in a resolvable particle size range of several microns to a few cm between two setups. The invention includes variable sampling length between two windows (e.g., a sampling volume of 71.4 mL per hologram at 12 cm). Holograms are recorded with a 49203280 pixels digital camera. i.e., 15.3 MB per image, at a maximum rate of 3.2 Hz, such that free stream water sampling a 14 L/minute occurs. This is orders of magnitude higher than sampling of other imaging systems while including larger/variable sample volume, inclusion of copper shutters to prevent biofouling during long-term deployments, including deployment in different operation modes. No single previous system achieves all these things at the same time.
MASKLESS IMAGING OF DENSE SAMPLES USING MULTI-HEIGHT LENSFREE MICROSCOPE
A method of imaging includes illuminating a sample spaced apart from an image sensor at a multiple distances. Image frames of the sample obtained at each distance are registered to one another and lost phase information from the registered higher resolution image frames is iteratively recovered. Amplitude and/or phase images of the sample are reconstructed based at least in part on the recovered lost phase information.
APPARATUS FOR PRODUCING A HOLOGRAM
An apparatus for producing a hologram includes a collimation lens configured to receive incoherent light emitted from an object; a spatial light modulator (SLM) that includes at least one diffractive lens which is configured to receive the incoherent light from the collimation lens and split the incoherent light into two beams that interfere with each other; and a camera configured to record the interference pattern of the two beams to create a hologram, wherein a ratio between a distance from the SLM to the camera and a focal length of the diffractive lens is greater than 1.
Apparatus and method for performing in-line lens-free digital holography of an object
The present disclosure relates to apparatuses and methods for performing in-line lens-free digital holography of objects. At least one embodiment relates to an apparatus for performing in-line lens-free digital holography of an object. The apparatus includes a point light source adapted for emitting coherent light. The apparatus also includes an image sensing device adapted and arranged for recording interference patterns resulting from interference from light waves directly originating from the point light source and object light waves. The object light waves originate from light waves from the point light source that are scattered or reflected by the object. The image sensing device comprises a plurality of pixels. The point light source comprises a broad wavelength spectrum light source and a pinhole structure. The image sensing device comprises a respective narrow band wavelength filter positioned above each pixel that filters within a broad wavelength spectrum of the point light source.
APPARATUS AND METHOD FOR RECORDING FRESNEL HOLOGRAMS
An apparatus for producing a hologram of an object includes a light source that emits an incoherent electromagnetic wave toward the object, and a masking device configured to display a mask, receive the incoherent electromagnetic wave emitted toward the object, mask the received incoherent electromagnetic wave according to the displayed mask, and produce a masked electromagnetic wave. The apparatus also includes an image recording device configured to capture an image of the masked electromagnetic wave, and a processing device configured to convert the image of the masked electromagnetic wave into the hologram of the object. A method for producing a hologram of an object is also described.
Analysis and sorting of objects in flow
A device and method for sorting objects immersed in a flowing medium are disclosed. An example device comprises a holographic imaging unit comprising one or more holographic imaging elements, a fluid handling unit comprising one or more microfluidic channels configured to conduct flowing medium along a corresponding holographic imaging element and at least one microfluidic switch arranged downstream of an imaging region in the microfluidic channel configured to direct objects in the flowing medium into a one of a plurality of outlets. The example device also comprises a processor configured to determine real-time characterizations of holographic diffraction images obtained for the moving objects. The processing unit is further configured to control the at least one microfluidic switch in response to the real-time characterizations.
METHOD FOR OBSERVING A SAMPLE BY LENS-FREE IMAGING
The invention relates to a method for observing a sample, in particular an anatomopathological slide formed from a thin thickness of a sampled biological tissue. It includes a step of illuminating the sample with a light source and acquiring, with an image sensor, an image representing the light transmitted by the sample. The image undergoes holographic reconstruction, so as to obtain a representation, in the plane of the sample, of the light wave transmitted by the latter. The method includes applying an impregnating fluid to the sample, such that the sample is impregnated with said impregnating liquid, said impregnating liquid having a refractive index strictly higher than 1.