The present invention relates to the technical fields of optical imaging, microwave imaging, radar detection, sonar, ultrasonic imaging, and target detection, imaging identification and wireless communication based on media such as sound, light and electricity, and in particular, to a fast imaging method suitable for passive imaging and active imaging and application of the fast imaging method in the above fields. According to the method provided by the present invention, image field distribution corresponding to a target is achieved based on a lens imaging principle, in combination with an electromagnetic field theory, according to a target signal received by an antenna array, through the amplitude and phase weighting of a unit signal and by using an efficient parallel algorithm. The method provided by the present invention has the advantages of capability of being compatible with passive imaging and holographic imaging, good imaging effect, small operation amount, low hardware cost, high imaging speed and suitability for long-distance imaging, and can be widely applied in the fields of optical imaging, microwave imaging, radar detection, sonar, ultrasonic imaging, and target detection, imaging identification and wireless communication based on media such as sound, light and electricity.

The present invention relates to the technical fields of optical imaging, microwave imaging, radar detection, sonar, ultrasonic imaging, and target detection, imaging identification and wireless communication based on media such as sound, light and electricity, and in particular, to a fast imaging method suitable for passive imaging and active imaging and application of the fast imaging method in the above fields. According to the method provided by the present invention, image field distribution corresponding to a target is achieved based on a lens imaging principle, in combination with an electromagnetic field theory, according to a target signal received by an antenna array, through the amplitude and phase weighting of a unit signal and by using an efficient parallel algorithm. The method provided by the present invention has the advantages of capability of being compatible with passive imaging and holographic imaging, good imaging effect, small operation amount, low hardware cost, high imaging speed and suitability for long-distance imaging, and can be widely applied in the fields of optical imaging, microwave imaging, radar detection, sonar, ultrasonic imaging, and target detection, imaging identification and wireless communication based on media such as sound, light and electricity.

An optical image generation system including: a spatial light modulator (SLM) configured to receive an input collimated laser beam and modulate the wavefront of the laser beam; one or more optical elements configured to project the modulated laser beam onto a focal plane; a first mirror and a second mirror situated at the focal plane, an edge of the first mirror being adjacent to an edge of the second mirror, the first mirror reflects a first portion of the modulated laser beam in a first direction, the second mirror reflects a second portion of the modulated laser beam in a second direction; and an objective lens projects the first and second portions into a combined image; wherein the zeroth order diffraction is block or suppressed at the center of the focal plane.

A computer-implemented method and a system for object identification and/or classification. The computer-implemented method includes receiving digital hologram data of a digital hologram of an object. The digital hologram data comprises phase information and magnitude information. The computer-implemented method further includes processing the digital hologram data based on a neural-network-based ensemble model to identify and/or classify the object.

A computer-implemented method and a system for object identification and/or classification. The computer-implemented method includes receiving digital hologram data of a digital hologram of an object. The digital hologram data comprises phase information and magnitude information. The computer-implemented method further includes processing the digital hologram data based on a neural-network-based ensemble model to identify and/or classify the object.

A direct-retina holographic projection system includes first and second spatial light modulators (SLMs) and a control module. The first SLM receives a beam of light and dithers the beam of light at a predetermined frequency to provide multiple instances of the beam of light. The second SLM receives the instances of the beam of light, displays an encoded phase hologram of a graphic image to be projected, and diffracts the instances of the beam of light to provide instances of the encoded phase hologram with the same graphic image but multiplied with dithered wavefronts. The control module: iteratively adjusts a parameter of the first SLM to generate the instances of the beam of light; and controls operation of the second SLM to, based on the instances of the beam of light, display multiple instances of the graphic image on a retina of an eye of a viewer.

A holographic projector includes a spatial light modulator, a light receiving member and a driver. The spatial light modulator is arranged to receive and represent a computer-generated hologram and spatially modulate light incident on the spatial light modulator to form a holographic reconstruction in accordance with the computer-generated hologram. The light receiving member is arranged to receive spatially modulated light along an optical axis from the spatial light modulator and the holographic reconstruction is formed on the light receiving member. The driver is coupled to the light receiving member to move the light receiving member in a plane. The driver is configured to move the light receiving member while maintaining an orientation of the light receiving member relative to the spatial light modulator substantially constant.

A holographic projector includes a spatial light modulator, a light receiving member and a driver. The spatial light modulator is arranged to receive and represent a computer-generated hologram and spatially modulate light incident on the spatial light modulator to form a holographic reconstruction in accordance with the computer-generated hologram. The light receiving member is arranged to receive spatially modulated light along an optical axis from the spatial light modulator and the holographic reconstruction is formed on the light receiving member. The driver is coupled to the light receiving member to move the light receiving member in a plane. The driver is configured to move the light receiving member while maintaining an orientation of the light receiving member relative to the spatial light modulator substantially constant.

Provided are an improved holographic reconstruction apparatus and method. A holographic reconstruction method includes: obtaining an object hologram of a measurement target object; extracting reference light information from the obtained object hologram; calculating a wavenumber vector constant of the extracted reference light information, and generating digital reference light by calculating a compensation term of the reference light information by using the calculated wavenumber vector constant; extracting curvature aberration information from the object hologram, and then generating digital curvature in which a curvature aberration is compensated for; calculating a compensated object hologram by multiplying the compensation term of the reference light information by the obtained object hologram; extracting phase information of the compensated object hologram; and reconstructing 3-dimensional (3D) shape information and quantitative thickness information of the measurement target object by calculating the quantitative thickness information of the measurement target object by using the extracted phase information of the compensated object hologram.

Provided are an improved holographic reconstruction apparatus and method. A holographic reconstruction method includes: obtaining an object hologram of a measurement target object; extracting reference light information from the obtained object hologram; calculating a wavenumber vector constant of the extracted reference light information, and generating digital reference light by calculating a compensation term of the reference light information by using the calculated wavenumber vector constant; extracting curvature aberration information from the object hologram, and then generating digital curvature in which a curvature aberration is compensated for; calculating a compensated object hologram by multiplying the compensation term of the reference light information by the obtained object hologram; extracting phase information of the compensated object hologram; and reconstructing 3-dimensional (3D) shape information and quantitative thickness information of the measurement target object by calculating the quantitative thickness information of the measurement target object by using the extracted phase information of the compensated object hologram.