Spatiospectral structure of wave phase matching in birefringent crystals has a strong dependence on the geometry of the acousto-optic interaction and incident light spectrum. This dependence defines details of light beam profile transformation. It is especially important for imaging applications related to a large angular aperture and a wide spectral bandwidth of the incident light. In this paper, we demonstrate accurate three-dimensional plotting of a light transmission pattern without small birefringence approximation. The rather complicated shape of the phase-matching locus in the spatiospectral domain inevitably leads to residual spatially nonuniform chromatic aberrations in the spectral image. Theoretical consideration and computational modeling are confirmed by the experiments on Bragg diffraction in paratellurite crystal. The results are especially important for the development of acousto-optical imaging devices and laser beam shaping technologies.

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We report on wavelength-multiplexed digital holographic imaging based on simultaneous Bragg diffraction of wideband light by several ultrasound waves of different frequencies in crystalline media. This technique is easy to implement, avoids spectral scanning, and is applicable in various digital holography schemes. It also enables single-shot acquisition of a few spectral fringe patterns by a single monochrome sensor and wavelength demultiplexing of the resulting interferogram. We have assembled a Mach–Zehnder interferometer with an acousto-optical tunable filter operating in the multifrequency mode and have validated the proposed technique by dual-, three-, and four-wavelength quantitative phase imaging of the test samples.

Acousto-optic (AO) anisotropic interaction in uniaxial birefringent crystals is a widespread and versatile approach to tunable spectral filtration of light. Its principal constraints are limited values of spectral and angular bandwidth restricting the light transmission and imaging performance of AO filters. A way to overcome these drawbacks is simultaneous Bragg diffraction of two or more light beams. In this paper, we discuss and compare the main features of four available modes of anisotropic wide-aperture AO interactions in uniaxial birefringent crystals. We calculate the angular aperture, spectral resolution and other parameters and estimate the spectral image quality features related to each one. Theoretical consideration and computational modeling are carried out for tellurium dioxide (TeO2)—the main AO crystal. Derived results are important for the development of AO imaging devices, particularly multi-channel AO tunable filters.

We address the optical design procedure of prism-based stereoscopic imaging systems. Conventional approach includes two sequential stages: selection of the hardware and development of the proper digital image processing algorithms. At each of these stages, specific techniques are applied, which are almost unrelated to each other. The main requirements to the imaging system include only the key parameters and the image quality. Therefore, the insufficient measurement accuracy may be revealed only after the prototype is assembled and tested. In this case, even applying complex time-consuming image processing and calibration procedures does not ensure the necessary precision. A radical solution of this issue is to include the measurement error estimation into the optical design stage. In this research, we discuss a simplified implementation of this approach and demonstrate the capabilities of optical design software for this purpose. We demonstrate the effectiveness of this approach by the analysis and optimization of a prism-based stereoscopic imager with respect to required 3D measurement accuracy. The results are meaningful for the development of 3D imaging techniques for machine vision, endoscopic and measurement systems.

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