Abstract:
A system for motility contrast imaging a biological target within tissue comprising a CCD array; an illumination source for generating an incoming beam; a first beam splitter for receiving the incoming beam and producing an object beam and a reference beam; a second beam splitter for illuminating a multitude of biological targets with the object beam and for directing backscattered object beams towards the CCD array; a computer-controlled delay stage for zero-path-matching the reference beam to the backscattered object beams; a reference beam that intersects the backscattered object beams at an angle to produce a series of interference fringes that modulate Fourier-domain information; and a computer for receiving a time series of Fourier-domain information. The interference fringes between the backscattered object beam and the reference beam are recorded by the CCD array and passed to the computer which constructs a digital hologram at successive times.
Abstract:
The invention concerns a quantitative phase-contrast digital holography method for the numerical reconstruction of images, comprising the following steps: A. acquiring a digital hologram of an investigated object; B. reconstructing the digital hologram in a reconstruction plane; C. reconstructing the complex field for the digital hologram; D. obtaining the phase map starting from the complex field; the method being characterised in that it further comprises the following steps: E. applying to the digital matrix of any step A, B, C a shear s x and/or s y respectively along directions x and/or y; F. subtracting the matrix obtained in step E from the starting matrix of step E, or vice versa; G. integrating the obtained matrix along directions x and/or y; H. calculating at least a defocus aberration term; the steps G to being subsequent to step D. The invention further concerns a digital holography apparatus which implements the method of the invention.
Abstract:
The invention concerns a method and an apparatus for measuring and computing the Amplitude Point Spread Function (APSF). The invention may be advantageously used in the field of Digital Holographic Microscopy (DHM).
Abstract:
Un procédé d'imagerie acousto-optique d'un objet à imager (OBJ) comprend les étapes consistant à (a) générer une onde optique incidente (INC), et une onde optique de référence (REF), cohérente avec l'onde incidente (INC), (b) faire vibrer à une fréquence acoustique une zone de l'objet à imager (OBJ), (c) appliquer l'onde incidente (INC) sur l'objet à imager (OBJ), et générer ainsi une onde signal diffusée (DIF), (d) appliquer au moins une partie de l'onde signal diffusée sur un dispositif de détection (DET), (e) appliquer l'onde de référence (REF) sur le dispositif de détection (DET) sans la faire passer à travers l'objet à imager (OBJ), ce qui génère un interférogramme I ( r , t), (f) extraire de l'interférogramme I ( r , t) une information numérique, et (g) obtenir les coordonnées (U, V, W) d'un point de mesure de l'objet à imager (OBJ) auquel l'information numérique est relative.
Abstract:
Die Erfindung betrifft ein interferometrisches Verfahren, bei dem das von einem Objekt gestreute Probenlicht auf eine elektronische Kamera abgebildet wird, wobei ein Probenlichtanteil Streuorten auf einer Schnittfläche im Innern des Objekts zugeordnet wird. Dieser Probenlichtanteil kann durch eine Verarbeitung des Kamerabildes von den Beiträgen der übrigen Probenlichtanteile separiert werden und führt auf ein Schnittbild. Ein besonderer Vorteil der Erfindung liegt darin, dass nacheinander mehrere parallel verlaufende Schnittflächen mit vorbestimmten Abständen zueinander im Innern des Objekts abgelichtet werden können. Eine solche Sequenz von Schnittbildern kann zum Errechnen eines Volumenmodells des Objekts verwendet werden. Die Erfindung ist insbesondere auf die lebende Retina anwendbar und gestattet innerhalb weniger Sekunden einen dreidimensionalen Retina-Scan mit einem kostengünstigen und ggf. handgehaltenen Gerät. Anwendungsmöglichkeiten liegen in der Ophthalmologie und in der Biometrie.
Abstract:
The present invention discloses a method for analyzing a liquid cell sample, comprising the steps of: a) providing at least one liquid cell sample in a sample vial; b) obtaining data linked to the cells in the sample by performing differential digital holographic microscopy on said liquid cell sample in said sample vial. In a second aspect, the invention also provides for a system for analyzing a liquid cell sample, comprising (i) a differential digital holographic microscope comprising illumination means, a differential interferometer and a digital recording device connected to a processing device such as a computer; (ii) at least one exchangeable sample vial comprising a liquid cell (iii) a movable sample vial holder; characterized in that (iv) said sample vial holder is adapted to receive said sample vial; (v) said sample vial holder is adapted to position said sample vial such that the focal plane of the objective lens of said differential digital holographic microscope lies in the vial.
Abstract:
The present invention is related to a method for characterising transparent objects (2, 3) in a transparent medium (1), said transparent objects (2, 3) presenting an optical focal area (5, 6) said method comprising the steps of: illuminating a sample comprising the objects (2, 3) to be characterised by means of a directional light (7) source, thereby inducing light intensity peaks (5, 6) at the focal area of said transparent objects; determining at least one characteristic of the light intensity peak (5, 6) induced by said object to be characterised, determining from said light intensity peak (5, 6) at least one property of said object.