A high-speed digital holography based on a liquid crystal Spatial Light Modulator (LC-SLM) is presented. The
production of multi-beam and control of their delay time can be achieved by controllable wavefront coding theory. In this
paper, a Dammann phase grating was designed using a SLM to product multi-beam for extremely high speed digital
holographic imaging. The required beam deflection could be obtained by adjusting programmable phase mask for
controlling the spatial diffraction of input beam. The framing time is decided by interval beam angles and the distances
between input plane and record plane. Theoretical derivate of generation multi beams based on SLM was proposed, and
phase recover software was also made.
We demonstrated a single-shot quasi-on-axis digital holography which is capable of simultaneously capturing two-step phase-shifting interferences. A dual-channel interferometer was employed to monitor the Gouy phase-shifting between two orthogonal polarized references which was introduced by two confocal lenses. A new algorithm was derived for reconstruction the complex field of the object’s wavefront according to the feature of Gouy phase-shifting. Simulation was carried out and recover software was also made. The proposed approach can also be applied to single-shot quasi-onaxis digital holography for real time measurement.
In this paper, the characteristics of Fraunhofer digital holography are investigated. With Fraunhofer digital holography,
we could simplify the calculational and reconstructed process. Moreover, the spectrum of the hologram did not contain
the original images and the limitation of recording frame caused by the size of objects was reduced. The number of
recording frame could be increased, especially for the objects of concentrative spectrum. Thus, with Fraunhofer digital
holography, it could not only simplify the process of reconstruction and calculation, but also improve the framing
capability in high-speed photography.
This paper analyses a disparity correction of an advanced multi-sparkle camera system. This system is also called
Cranz-Schardin camera, which a method to achieve extreme high-speed photography. The camera axis in this system
have an angle with principal optical axis, so each image taking by different cameras in system is formed by different
orientation projections of the object, and this process generates parallax among the different cameras. In order to solve
this problem, camera calibration method is setting up after a detailed analysis of this system. A planar calibration is used
as standard reference object in experiment. And image corresponding relationship among different cameras can be built
through learning the position changes of feature points in different cameras. Then, grab pictures from transient
phenomenon which need to be analyzed, and after image processing on these pictures with the image corresponding
relationship, the disparity influence on experiment images in this advanced multi-sparkle camera system would be
In this paper, we proposed a new method, controllable rectangle filter, to improve the resolution of reconstruction in
multi-frame digital holography. In this method, the entire process needs only one hologram with multi-frame digital
holographic interference and the different images' spectrum can be obtained separately without mutual influence.
Therefore the size limiting of the recording objects is reduced and the frame amounts can be increased. Moreover, the
nonessential information of zero-order and the conjugate image can be eliminated well, and the resolution of the
reconstructed images is enhanced. Theoretical analysis and experimental results show that it is a realistic and practical
Holography based extreme high-speed photography (EHSP) is a novel technique to study extreme high speed
photography with holography. In order to get multi-frame holograms in high speed holography, studying the framing
principle is very important. Coding reference beam is essential to get multi-frame digital hologram. In this paper,
multi-frame digital holography based on Fourier transformed setup is presented. We study the azimuth encoding method
for the recording theoretically. Point light sources in x-y plane arrange in a narrow circle are selected as reference wave
and the object wave is located in origin of x-y plane. Every point light source stands for a certain azimuth angular. For
the radius of the circle is much smaller than the recording distance, it can be approximately regarded as quasi-on-axis
digital holography. Multiple digital holograms are stored in a single CCD frame, and reconstructed simultaneously. For a
certain magnitude of object, the minimize framing angular, namely, the least angular of two neighboring points, is
carefully studied. And stationary experiment results are also presented. Theoretic and experimental result show that
multi-frame digital holograms with azimuth encoding method can get multiple frames that the EHSP requires. This
indicates that, this encoding method can be used in high speed photography to get multi-frame images.