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We propose a phase-shifting interferometry technique using only two in-line phase-shifted self-interference holograms. There is no requirement for additional recording or estimation in the measurement. The proposed technique adopts a mathematical model for self-interference digital holography. The effectiveness of the proposed technique is demonstrated by experiments on incoherent digital holographic microscopy and color-multiplexed fluorescence digital holography with computational coherent superposition. Two-color-multiplexed four-step phase-shifting incoherent digital holography is realized for the first time, to the best of our knowledge, using the proposed technique.

Several types of augmented reality three-dimensional display systems are introduced. All systems consist of a holographic optical element fabricated by wavefront printing technique to be used as an optical functional screen.

Phase-shifting interferometry selectively extracting wavelength information has been proposed since 2013, which is called computational coherent superposition (CCS) of multiple wavelengths. In this proceeding, we apply CCS to self-interference incoherent holography and construct single-path, mechanical-motion-free, wavelength-multiplexed, incoherent multicolor digital holographic microscopy systems. Also, we numerically investigate quantum fluctuation in phase-shifting interferometry for the sensing of weak light such as natural light and nonlinear light. After that, we briefly discuss the difference between the digital holography systems with CCS and phase-shifting interferometry with a Bayer color image sensor.

We present approaches for simultaneous, holographic, and microscopic multicolor motion-picture sensing of multiple natural light sources. We utilize single-shot incoherent digital holography with a polarization-imaging sensor, phase-shifting interferometry, and computational coherent superposition (CCS) as approaches.

Light-in-flight recording by holography can record light propagation with a single-shot exposure in principle and can reconstruct it as spatially and temporally continuous motion pictures. We calculated computer-generated holograms based on light-in-flight recording by holography, and printed them by a wavefront printer in order to prove the validity of the numerical simulation model based on light-in-flight recording by holography. Because we reconstructed motion pictures of light propagation from the printed holograms, we successfully showed the validity of the numerical simulation model.

Concave micro-mirror arrays fabricated as holographic optical elements are used in projector-based light field displays due to their see-through characteristics. The optical axes of each micro-mirror in the array are usually made parallel to each other, which simplifies the fabrication, integral image rendering, and calibration process. However, this demands that the beam from the projector be collimated and made parallel to the optical axis of each elemental micro-mirror. This requires additional collimation optics, which puts serious limitations on the size of the display. In this Letter, we propose a solution to the above issue by introducing a new method to fabricate holographic concave micro-mirror array sheets and explain how they work in detail. 3D light field reconstructions of the size 20 cm×10 cm and 6 cm in depth are achieved using a conventional projector without any collimation optics. Japan Society for the Promotion of Science (JSPS) (16H01742, 18H03281, 26790064).

See-through head-up 3D display is being reported, which uses a commercial projector as the light source and a lens array in the form of holographic optical element (HOE). By introducing novel technique in the fabrication process of the HOE based lens array, we have significantly simplified the display system by not using any collimation optics. Light field reconstructions of a 3D scene of size 20cm (Width) × 10cm (Height) × 5 cm (Depth) is successfully demonstrated with a view angle of 10-degrees.

We present optical experimental results for a high-resolution three-dimensional (3D) holographic display system based on dense ray sampling and integral imaging capture. Holograms are generated based on re-sampling the rays from 2D images captured by an integral imaging system. In addition, we demonstrate a depth of field extension technique during the integral imaging capture by combining an amplitude modulated lens technique and a blind convolution approach. The optically reconstructed images of the holographic display system are shown and compared with conventional integral imaging-based holographic displays for different scenes.

We introduce a new algorithm for calculating computer generated hologram (CGH) using ray-sampling (RS) plane. RS plane is set at near the object and the light-rays emitted by the object are sampled at the plane. Then the light-rays are transformed into the wavefront with using the Fourier transforms. The wavefront on the CGH plane is calculated by wavefront propagation simulation from RS plane to CGH plane. The proposed method enables to reproduce high resolution image for deep 3D scene with angular reflection properties such as gloss appearance.

Several wavefront printers have been recently proposed. Since the printers can record an arbitrary computer-generated wavefront, they are expected to be useful for fabricating complex mirror arrays used in front projection 3-D screens without using real existing optics. We prototyped two transparent reflective screens using our hologram printer in experiments. These screens could compensate for a spherically distorted reference wave caused by a short projection distance to obtain an ideal reference wave. Owing to the use of the wavefront-printed screen, the 3-D display was simply composed of a normal 2-D projector and a screen without using extra optics. In our binocular system, reflected light rays converged to the left and right eyes of the observer and the crosstalk was less than 8%. In the light field system, the reflected light rays formed a spatially sampled light field and focused a virtual object in a depth range of ±30 mm with a ±13.5-deg viewing angle. By developing wavefront printing technology, a complex optics array may easily be printed by nonprofessionals for optics manufacturing.

Computational holography based on the mutual conversion between ray information and wavefront is introduced. By dealing with ray and wavefront domains properly in the hologram calculation process, the proposed method can be compatible both domain's advantages. In the optical experiment, some main features of proposed method; the photorealistic image reconstruction by using computer graphics technique, the correct occlusion effect by just ray overwriting process, and also the reproducibility even for the deep 3D scene at high resolution, are demonstrated by the electronic-holography system developed by NICT.

In this paper, we overview a high resolution three-dimensional (3D) holographic display using 2D images captured in an integral imaging system and dense ray resampling technique. Holograms are generated the resampled rays from the 2D images. This method can improve the display resolution because each object is captured in focus and light-ray information is interpolated and resampled with high density on ray-sampling plane located near the object. Numerical experimental results for different scenes show that the presented holographic display technique can reconstruct multiple objects at different depths with higher resolution compared to conventional integral imaging-based holographic displays.

The electronic holographic three-dimensional images produced by reflection-type multiple spatial light modulators have limited scalability. We propose latitude enhancement method with a newly devised space-saving image-readout optical system to produce large color full-parallax images.

We present a high-resolution three-dimensional (3D) holographic display using a set of elemental images obtained by passive sensing integral imaging (II). Hologram calculations using a high-density ray-sampling plane are achieved from the elemental images captured by II. In II display, ray sampling by lenslet array and light diffraction limits the achievable resolution. Our approach can improve the resolution since target objects are captured in focus and then light-ray information is interpolated and resampled with higher density on ray-sampling plane located near the object to be converted into the wavefront. Numerical experimental results show that the 3D scene, composed of plural objects at different depths from the display, can be reconstructed with order of magnitude higher resolution by the proposed technique.