A microscope comprising a coherent light source producing a coherent light beam, a light beam guide system comprising a beam splitter configured to split the coherent light beam into a reference beam and a sample illumination beam, a sample holder configured to hold a sample to be observed, a sample illumination device configured to direct the sample illumination beam through the sample and into a microscope objective, a beam reuniter configured to reunite the reference beam and sample illumination beam after passage of the sample illumination beam through the sample to be observed, and a light sensing system configured to capture at least phase and intensity values of the coherent light beam downstream of the beam reuniter.

A system for lens-free imaging includes a processor in communication with a lens-free image sensor. The processor is programmed to operate the image sensor to obtain a hologram ??. The processor is further programmed to generate, from the hologram, a reconstructed image X and phase W at a focal depth z using an assumption of sparsity.

Apparatuses and methods for improved reconstructions of electron-based holograms are disclosed herein. An example method at least includes forming a hologram of a sample and a known object, forming a reconstruction of the known object using a reconstruction algorithm, comparing the reconstruction of the known object to a reference reconstruction of the known object, and adjusting the reconstruction algorithm based on the comparison of the reconstruction of the known object to the reference reconstruction of the known object. The example method may further include forming a reconstruction of the sample using the adjusted reconstruction algorithm.

A dark field digital holographic microscope and associated metrology method is disclosed which is configured to determine a characteristic of interest of a structure. The dark field digital holographic microscope includes an illumination branch for providing illumination radiation to illuminate the structure; a detection arrangement for capturing object radiation resulting from diffraction of the illumination radiation by the structure; and a reference branch for providing reference radiation for interfering with the object radiation to obtain an image of an interference pattern formed by the illumination radiation and reference radiation. The reference branch has an optical element operable to vary a characteristic of the reference radiation so as to reduce and/or minimize variation in a contrast metric of the image within a field of view of the dark field digital holographic microscope at a detector plane.

The holographic Christmas tree is a holographic device. The holographic Christmas tree projects a three-dimensional image of a Christmas tree. The holographic Christmas tree includes a pedestal, a holographic projector, a substrate, and an image. The image is the three-dimensional image of a Christmas tree. The holographic substrate projects the image into the substrate. The pedestal contains the holographic projector.

Apparatuses and methods for comparative holographic imaging to improve structural and molecular information of reconstructions is disclosed herein. An example method at least includes acquiring a plurality of holograms of a sample, wherein each hologram of the plurality of holograms is acquired at a different electron beam energy, and determining atomic and structural information of the sample based at least on a comparison of at least two of the holograms of the plurality of holograms.

A method comprises obtaining input data comprising a hologram of a 3-dimensional (3D) particle field, a depth map of the 3D particle field, and a maximum phase projection of the 3D particle field. The method also comprises applying a U-net convolutional neural network (CNN) to the input data to generate output data. Encoder blocks have residual connections between a first layer and a second layer that skips over a convolution layer of the encoder block. Decoder blocks have residual connections between a first layer and a second layer that skips over a convolution layer of the decoder block. The output data includes a channel in which pixel intensity corresponds to relative depth of particles in the 3D particle field and an output image indicating locations of centroids of the particles in the 3D particle field.

Apparatuses and methods for improved reconstructions of electron-based holograms are disclosed herein. An example method at least includes forming a hologram of a sample and a known object, forming a reconstruction of the known object using a reconstruction algorithm, comparing the reconstruction of the known object to a reference reconstruction of the known object, and adjusting the reconstruction algorithm based on the comparison of the reconstruction of the known object to the reference reconstruction of the known object. The example method may further include forming a reconstruction of the sample using the adjusted reconstruction algorithm.

Apparatuses and methods for comparative holographic imaging to improve structural and molecular information of reconstructions is disclosed herein. An example method at least includes acquiring a plurality of holograms of a sample, wherein each hologram of the plurality of holograms is acquired at a different electron beam energy, and determining atomic and structural information of the sample based at least on a comparison of at least two of the holograms of the plurality of holograms.

An optical measurement system comprises a polarization beam splitter for dividing an incident beam into a reference beam and a measurement beam, a first beam splitter for reflecting the measurement beam to form a first reflected measurement beam, a spatial light modulator for modulating the first reflected measurement beam to form a modulated measurement beam, a condenser lens for focusing the modulated measurement beam to an object to form a penetrating measurement beam, an objective lens for converting the penetrating measurement beam into a parallel measurement beam, a mirror for reflecting the parallel measurement beam to form an object beam, a second beam splitter for reflecting the reference beam to a path coincident with that of the object beam, and a camera for receiving an interference signal generated by the reference beam and the object beam to generate an image of the object.