A method for observing a sample is provided, including illuminating the sample with a light source and forming a plurality of images, by an imager, the images representing the light transmitted by the sample in different spectral bands. From each image, a complex amplitude representative of the light wave transmitted by the sample is determined in a determined spectral band. The method further includes backpropagation of each complex amplitude in a plane passing through the sample, determining a weighting function from the back-propagated complex amplitudes, propagating the weighting function in a plane along which the matrix photodetector extends, updating each complex amplitude, in the plane of the sample, according to the weighting function propagated.

Provided is a digital holographic image-taking apparatus, including: an illumination portion (10) having a light emission surface (14D) for emitting illumination light toward an object (1), the illumination light having a specific wavelength in a coherent plane waveform; and an image sensor (50) having an pixel array (51) including two-dimensionally arranged pixels, the image sensor (50) capturing an interference pattern generated based on the illumination light having acted on the object (1), in which the following conditional expression is satisfied: 0.0000001<Z.sup.2/S<16, where S represents the area of the light emission surface (14D), and Z represents the distance from the light emission surface (14D) to the pixel array (51).

A manufacturing method of an optical element applied to a miniature microscope includes the steps of: emitting a signal light and a reference light to an optical material; and forming a plurality of gratings on the optical material by interfering the signal light and the reference light. A miniature microscope is also disclosed.

The invention relates to a method for observing a sample, in particular an anatomopathological slide formed from a thin thickness of a sampled biological tissue. It includes a step of illuminating the sample with a light source and acquiring, with an image sensor, an image representing the light transmitted by the sample. The image undergoes holographic reconstruction, so as to obtain a representation, in the plane of the sample, of the light wave transmitted by the latter. The method includes applying an impregnating fluid to the sample, such that the sample is impregnated with said impregnating liquid, said impregnating liquid having a refractive index strictly higher than 1.

The present disclosure relates to devices and methods configured to perform drug screening on cells. At least one embodiment relates to a lens-free device for performing drug screening on cells. The lens-free device includes a substrate having a surface. The lens-free device also includes a light source positioned to illuminate the cells, when present, on the substrate surface with a light wave. The lens-free device further includes a sensor positioned to detect an optical signal caused by illuminating the cells. The substrate surface includes a microelectrode array for sensing an electrophysiological signal from the cells.

A digital holographic microscope is provided. The digital holographic microscope includes a light source, a grating, an image sensing device, and an optical module. The light source is configured for providing a light beam. The grating is disposed between the light source and a sample. The grating is configured for splitting the light beam into a reference light beam and an object light beam. The image sensing device is configured for collecting the reference light beam, and collecting the object light beam reflected from the sample. The optical module is disposed between the light source and the sample, and is configured for guiding the reference light beam to the image sensing device, and guiding the object light beam to the sample.

The present invention is related to an holographic probe device for recording a gabor hologram comprising: a coherent optical fiber bundle comprising a distal end and a proximal end; a recording medium optically coupled to the proximal end of the coherent optical fiber bundle; a light source producing in use a single light beam, illuminating the distal end of the coherent optical fiber bundle and the object to be observed.

The imaging apparatus includes an optical system dividing light into object and reference beams and causing the object beam and the reference beam to interfere with each other to form interference fringes on an image sensor. A processor performs multiple imaging processes for the interference fringes with different incident angles of the object beam to an object, a first process to acquire a transmitted wavefront for each incident angle and a second process to calculate a three-dimensional refractive index distribution from the transmitted wavefronts. The apparatus includes a modulator changing a phase distribution of light in any one of an optical path from a light source to a dividing element, a reference beam path and an optical path from a combining element to the image sensor and causes the modulator to change the phase distribution in at least one of the multiple imaging processes.

Imaging apparatus and methods using diffraction-based illumination are disclosed. An example apparatus includes a diffraction grating to redirect light from a light source toward a sample to thereby illuminate the sample. The example apparatus also includes an image sensor to detect a diffraction pattern created by the illuminated sample.

A holographic image recording method is disclosed, that is realized through utilizing a holographic image fetching and recording device, including the following steps: using an image fetching device to fetch an image of a target object placed on a rotation table rotating at a fixed speed, the image thus obtained is transmitted to a display panel through a connection line; using a light emitting unit to emit coherent light to a first reflector; that reflects the coherent light to light splitter; and the light splitter splits the coherent light along a first light path and a second light path into an object light and a reference light, and transmits them onto a holographic film to interfere with each other, to form a holographic image. A holographic image reconstructing method is also disclosed, to reconstruct and form a 3D holographic image floating above the holographic film.