Abstract:
The subject matter disclosed herein pertains to a method for screening drugs using second-harmonic generation microscopy. The tissue is scanned with a pulsed laser light which has an excitation wavelength. At least some of microtubules within the tissue produce generated light with a second-harmonic wavelength that is half the excitation wavelength. A microtubule pattern within the tissue is determined based on an analysis of the generated second-harmonic wavelength.
Abstract:
Wavefront sensing apparatus comprises a beam splitter (106) for combining a wavefront to be characterised (105) with a frequency-shifted plane wavefront (111) and a bundle of optical fibres (112) arranged to detect the combined beam at a plurality of positions across the combined beam. Output from individual fibres of the bundle are detected to produce corresponding heterodyne signals, the phases of which are extracted by demodulation. By fitting the extracted phases to an assumed functional form for the phase of the wavefront to be characterised, the piston, tip, tilt and radius of curvature phase parameters of the wavefront to be characterised may be found at the position of the fibre bundle. In contrast, prior art methods of wavefront characterisation only allow the piston phase of the wavefront to be characterised to be obtained.
Abstract:
Optical apparatus for simultaneously focussing first and second coaxially spaced object planes in respective separate first and second areas of a common image plane (13) (such as the sensor of a CCD camera) comprises non-diffractive beamsplitter means for receiving light from said object planes along a common path (2) for transmission to said first and second image areas along respective first and second optical paths (3, 4), and reflective or transmissive focussing means (8) arranged to bring said first and second object planes into focus in said first and second areas. The object planes may be differentiated by having different length paths (3,4) (different physical lengths and/or using a differential optical delay), and/or by having different focussing powers in the two paths. In an add-on for a camera, differently curved mirrors of long focal length modify the main camera lens. Polarising optics may be used to separate the two images. The apparatus may be used for 3-D imaging or wavefront analysis.
Abstract:
Die vorliegende Erfindung betrifft eine Anordnung und ein Verfahren zur Wellenfrontanalyse mit einer Strahlungsquelle (8), die eine zu analysierende elektromagnetische Wellenfront elektromagnetischer Strahlung (1) emittiert, einer ortsauflösenden Detektoreinheit (4, 4a, 4b, 4c) zum Detektieren der elektromagnetischen Wellenfront und einer mit der Detektoreinheit (4, 4a, 4b, 4c) verbundenen elektronischen Auswerteeinheit (5, 7). Die mindestens einer Strahlführungseinheit (3) zum Führen der elektromagnetischen Strahlung (1), die nur diffraktiv und/oder reflektierend ausgebildet ist, weist mindestens eine Öffnung (3a, 3b, 3c) auf und die Detektoreinheit (4, 4a, 4b, 4c) ist in Ausbreitungsrichtung der elektromagnetischen Strahlung (1) hinter der mindestens einen Öffnung (3a, 3b, 3c) der Strahlführungseinheit (3) zum Detektieren eines Beugungsmusters der an der mindestens einen Öffnung (3a, 3b, 3c) gebeugten elektromagnetischen Strahlung (1) angeordnet.
Abstract:
The present invention relates to a wavefront sensor using a pair of screens, each having a two-dimensional array of circular apertures, to achieve Moiré effects, and its use to measure the slope of a wavefront.
Abstract:
The invention relates to an assembly and a method for wavefront analysis with a radiation source (8), which emits an electromagnetic wavefront of electromagnetic radiation (1) to be analysed, a spatially resolving detector unit (4, 4a, 4b, 4c) for detecting the electromagnetic wavefront, and an electronic evaluation unit (5, 7) connected to the detector unit (4, 4a, 4b, 4c). The at least one beam guiding unit (3) for guiding the electromagnetic radiation (1), which is only diffractive and/or reflective, has at least one opening (3a, 3b, 3c) and the detector unit (4, 4a, 4b, 4c) is arranged behind the at least one opening (3a, 3b, 3c) of the beam guiding unit (3) in the propagation of the electromagnetic radiation (1) in order to detect a diffraction pattern of the electromagnetic radiation (1) diffracted at the at least one opening (3a, 3b, 3c).
Abstract:
With regard to a particularly precise measurement of a wavefront using structurally simple means, a method for measuring a curved wavefront using a wavefront sensor is specified, wherein a plurality of measurements are carried out at different positions along the wavefront using at least one wavefront sensor in order to determine a local gradient of the wavefront at the different positions, which method is characterized in that the plurality of measurements are carried out with a substantially tangential alignment of a light entrance plane of the wavefront sensor(s) with the curved wavefront in each case. A corresponding apparatus for measuring a curved wavefront using a wavefront sensor is also specified.
Abstract:
A wavefront analyser is modified to simply determine the differences in amplitude and tilt which can exist between the different regions of an initial wavefront (S 0 ). To achieve this, interference between two waves only is produced from beams (F 1 , F 2 ) which come from neighbouring regions on the initial wavefront. Such an analyser can be used to coherently combine laser radiation produced by different sources arranged in parallel. Another use is for the determination of the differences in height and inclination which exist between the neighbouring mirror segments of a Keck telescope
Abstract:
A method, and apparatus for accomplishing the method, for determining a phase difference of a wavefront at a first (pupil) plane (P1), the wavefront propagating from the first plane to a second (image) plane (P2). The method includes the steps of providing an intensity of the wavefront at the first plane; measuring an intensity of the wavefront at the second plane; and determining the phase difference of the wavefront at the first plane in accordance with a transfer function that employs the provided intensity of the wavefront at the first plane and the measured intensity of the wavefront at the second plane. A single expression describing an Optical Transfer Function is developed and is shown to involve only the unknown aperture phase and known quantities. A solution to this expression, achieved by a polynomial expansion technique or by a sampling technique, is shown to yield the phase at the aperture and, together with the intensity at the aperture, to define the aperture wavefront.