An in-line holographic microscope can be used to analyze on a frame-by-frame basis a video stream to track individual colloidal particles' three-dimensional motions. The system and method can provide real time nanometer resolution, and simultaneously measure particle sizes and refractive indexes. Through a combination of applying a combination of Lorenz-Mie analysis with selected hardware and software methods, this analysis can be carried out in near real time. An efficient particle identification methodology automates initial position estimation with sufficient accuracy to enable unattended holographic tracking and characterization.

A light detection device according to an aspect of the present disclosure includes a light detector, a first layer, a first optical coupler, and a second optical coupler. The light detector includes a first photodetector and a second photodetector. The first layer is disposed above the first photodetector and the second photodetector. The first layer is light-transmissive and has a first surface and a second surface opposing the first surface. The first optical coupler is disposed on at least one surface selected from the group consisting of the first surface and the second surface. The second optical coupler is disposed on the at least one surface. The first and second optical couplers are light-transmissive and disposed above the first and second photodetectors, respectively. The second surface is closer to the light detector than the first surface.

A microscope and method of microscopy having a light source for providing illumination light, a controllable manipulation device for generating in a variable manner an illumination pattern of the illumination light to be selected, an illumination beam path with a microscope lens for guiding the illumination pattern to a sample to be examined, a detector having a plurality of pixels for examining the fluorescent light emitted by the sample, a detection beam path for guiding the fluorescent light emitted by the sample to the detector, a main beam splitter for splitting illumination light and fluorescent light, a control and evaluation unit for controlling the manipulation device and for evaluating the data measured by the detector. The manipulation device is arranged in the illumination beam path upstream from the main beam splitter in the vicinity of an optically conjugated plane to the sample plane such that the pixel of the detector can be individually activated using the control and evaluation unit and in read out patterns to be selected and that the control and evaluation unit is designed to activate pixels of the detectors individually or in a selected read out pattern dependent on the selected illumination pattern.

Techniques to improve image quality in holography utilizing lenses made from materials with non-quantized anisotropic electromagnetic properties, such as birefringent materials, to advantageously split an incoming beam of light into two coincident beams with different focal lengths that interfere with one another and thus create holograms free of electro-optical or pixelated devices are disclosed for microscopy and other applications. The use of thin birefringent lenses and single crystal alpha-BBO lenses are introduced. Corresponding systems, methods and apparatuses are described.

A holographic imaging system comprises an imaging light source defining an imaging light path, an active light source defining an active light path directed at a target, a polarizer configured to modify the polarization of the active light path, a polarization beam splitter positioned in the active light path and the imaging light path, configured to separate the active light path and the imaging light path, and a photodetector positioned at a terminus of the active light path, configured to measure a reflection of the active light source. A method of holographic imaging is also described.

A microscopy method, and related microscope, including producing illumination radiation and directing it at a focus. The illumination radiation is switched temporally between at least two modes, such that focus modulation is effected at which temporally varying and mutually different mode fields of the illumination radiation are produced in the focus. The focus is guided at least over regions of a sample to be examined, wherein detection radiation in the sample is or may be brought about by the illumination radiation in the focus at least at a point of origin. The detection radiation is captured in a manner assigned to the at least one point of origin. In addition to the illumination radiation, at least one disexcitation beam of rays of disexcitation radiation is directed at the focus. The disexcitation radiation prevents the detection radiation from being brought about in the region that is illuminated by the disexcitation radiation.

Sub-diffraction limited fluorescent images using a fiber-based stimulated emission depletion (STED) microscope are reported. Both excitation and depletion beams are transported through polarization-maintaining fiber and a lateral resolution of 100 nm has been achieved.

The present invention is directed toward a system and method for STED nanography, which reduces background noise. To remove background noise from a STED image, the polarization of the STED beam is altered from that used to obtain the original image. A polarized image is obtained. This polarized image can then be subtracted from the original image to remove noise inherent to the image.

Methods and apparatus for obtaining a vibrational circular dichroism (VCD) image using a discrete frequency infrared (DFIR) microscope are disclosed. The method includes generating a pulsed laser beam comprising a spectral frequency, which may be tunable; modulating the laser beam to generate circularly polarized light; illuminating a sample and collecting, and detecting an optical signal transmitted or transflected from the location of the sample. The detected signal is demodulated at, for example, both the pulse frequency and the sum or difference of the pulse frequency and the modulating frequency to obtain an intensity value that correspond to the absorbance, and a polarization-dependent value that corresponds to the VCD. Other configurations of the apparatus may be employed to measure VCB and VLD.

A surface defect measuring apparatus and method by microscopic scattering polarization imaging is provided. The apparatus mainly comprises a laser, a first converging lens, a rotary diffuser, a second converging lens, a diaphragm, a third converging lens, a pinhole, a fourth converging lens, a polarizer, a half-wave plate, a polarizing beam splitter, an X-Y translation stage, a sample, a microscope lens, a quarter-wave plate, a micro-polarizer array, a camera and a computer. The micro-polarizer array is adopted to realize real-time microscopic scattering polarization imaging of the surface defects; a polarization-degree image is calculated to improve the sensitivity for detecting the surface defects of the ultra-smooth element, and the effective detection of the surface defects of a high-reflective coating element is also realized, and the requirement for rapid detection of the surface defects of a meter-scale large-aperture ultra-smooth element can be met.