Abstract:
A Raman microscopy imaging device (100) is described, having: a first laser light source (12) for emitting a first laser beam (16) having a first wavelength along a first light path (20); a second laser light source (44) for emitting a second laser beam (18) having a second wavelength, different from the first wavelength, along a second light path (22) physically separated from the first light path (20); a beam combining element (32) for collinearly combining the two laser beams (16, 18) in one shared light path (34) directed onto a sample; a detector (38) for sensing a measured signal on the basis of the two laser beams (16, 18) interacting with the sample; and an evaluation unit (40) for evaluating the measured signal sensed by the detector (38). According to the present invention the first laser light source (12) is embodied as a pulsed source, and the second laser light source (44) as a continuous source.
Abstract:
An acousto-optical filter element (114) is provided which has an acousto-optical crystal (118) having an acoustic signal transmitter (120) for generating acoustic signals in the acousto-optical crystal (118). The acousto-optical crystal (118) is designed to selectively spatially deflect light of a target wavelength from an input light beam (116) entering into the acousto-optical crystal (118), as a function of a high frequency applied to the acoustic signal transmitter (120), and to thereby produce a target light beam (126) having the target wavelength. In addition, the acousto-optical filter element (114) includes a spatial filter element (132) which is located in the target light beam (126) and is designed to selectively suppress the intensity of the target light beam (126) in a plane perpendicular to the propagation direction of the target light beam (126).
Abstract:
The invention relates to a microscope having an objective that focuses illuminating light to an illuminating light focus, and having a light-guiding fiber which transports the illuminating light and at whose end is arranged a fiber coupler that couples the illuminating light out of the light-guiding fiber and generates a preferably collimated illuminating light bundle. An element for modifying the shape of the illuminating light focus, which is prealigned relative to the illuminating light bundle to be coupled out, is arranged in or on the fiber coupler.
Abstract:
The invention relates to a microscope having an acousto-optic apparatus (13) that, with a mechanical wave that is characterized by a preferably adjustable frequency, removes from a polychromatic and collinear detected light bundle (18) portions of illuminated light, scattered and/or reflected at a sample, having an illuminating light wavelength associated with the frequency. The microscope is notable for the fact that a crystal (30) of the acousto-optic apparatus in which the mechanical wave propagates, and the propagation direction of the mechanical wave, are oriented relative to the detected light bundle incident into the crystal in such a way that the acousto-optic apparatus deflects, with the mechanical wave, both the portion of the detected light bundle having the illuminating wavelength and a first linear polarization direction, and the portion of the detected light bundle having the illuminating wavelength and a second linear polarization direction perpendicular to the first polarization direction, and thereby removes them from the detected light bundle.
Abstract:
An apparatus for damping sound in the optical beam path of a microscope, having an acoustic insulation housing for encapsulating a sound-emitting component, preferably a rapidly moving or oscillating beam deflection means, in particular a resonantly oscillating mirror, the housing comprising at least one optical entrance/exit opening, is characterized in that the housing, preferably the opening of the housing, is embodied and/or configured in such a way that the sound otherwise emerging from the housing is largely extinguished by destructive interference without thereby influencing the optical beam. A microscope having a corresponding apparatus is furthermore claimed.
Abstract:
In order to investigate a specimen (30) with the aid of a microscope (20), dye particles (40, 42) in the specimen (30) are excited to fluoresce with the aid of a first illumination light beam (24). Fluorescent light proceeding from the specimen (30) is directed via an optical arrangement (34) onto an areal sensor (36), the optical arrangement (34) acting on the fluorescent light in such a way that sub-beams of the fluorescent light interfere with themselves, so that interference patterns produced as a result of the interference are imaged on a sensitive surface of the areal sensor (36) and sensed thereby. Positions of the dye particles (40, 42) within the specimen (30) are ascertained as a function of the interference patterns.
Abstract:
A fluorescence lifetime imaging microscopy method with time-correlated single photon counting includes periodically exciting a sample to emit fluorescence photons, with a measurement interval being defined between each two successive excitation light pulses. A value characterizing fluorescence decay behavior is determined based on detection times of detected fluorescence photons, and imaging is performed based one the value. An analog detector signal is sampled within a plurality of sampling intervals within a respective one of the measurement intervals and is converted into a sequence of discrete signal values associated with the sampling intervals. It is determined based thereon whether more than a predefined number of fluorescence photons has been detected within the respective measurement interval. If more than the predefined number of fluorescence photons has been detected, the respective measurement interval is discarded in the step of determining the value characterizing the fluorescence decay behavior.
Abstract:
A device (10) for illuminating a sample (40) is described, having: at least one pulsed laser light source (12) for repeated emission of a first laser pulse along a first light path (14) and of a second laser pulse along a second light path (16) physically separated from the first light path; a superimposition element (32) for collinear superimposition of the two laser pulses in a shared light path (34); a delay stage (26) arranged in the first or the second light path (14, 16), for delaying one of the two laser pulses relative to the other laser pulse in such a way that the two laser pulses sent along the shared light path (34) onto the sample (40) exhibit a temporal superimposition; a shared chirp unit (36) arranged in the shared light path (34), for frequency-modifying influencing both of the first laser pulse and of the second laser pulse; and at least one separate chirp unit (18) arranged in the first light path (14), for frequency-modifying influencing only of the first laser pulse. The shared chirp unit (36) and the separate chirp unit (18) are coordinated with one another in order to achieve a target state. The separate chirp unit (18) is coupled to a control system (20) by which the separate chirp unit (18) is controllable with a control parameter dependent on the wavelength of the first laser pulse in order to establish the target state.
Abstract:
The invention relates to a beam combiner for a microscope, in particular a scanning microscope, which receives at least a first illuminating light bundle and a second illuminating light bundle and combines them into a collinear output light bundle, the first illuminating light bundle and the second illuminating light bundle having the same illuminating light wavelength but a different polarization, in particular linear polarization. The beam combiner is embodied as an acousto-optic beam combiner and is constructed and operated in such a way that by interaction with at least one mechanical wave, both the first illuminating light bundle and the second illuminating light bundle are diffracted and are thereby directed into a common optical axis.
Abstract:
A method for increasing the dynamic range of a silicon photomultiplier (SiPM) in particular with regard to the detection of high radiation intensities, individual avalanche photodiodes usually being biased with a bias voltage VR beyond a breakdown voltage VBR, with the consequence of an avalanche discharge of electrons that define the output signal, is characterized in that the output signals resulting from an incident radiation intensity are adjusted by modifying the bias voltage VR, the output signals being evaluated in the integration mode.