Investigation of limitations of optical diffraction tomography

Abstract

Optical diffraction tomography (ODT) applied to measurement of optical microelements is limited by low dynamic range, i.e., only objects with small deviations of refractive-index distribution can be measured. Therefore in this paper the limitations and errors of ODT are investigated throughout extensive numerical experiments. It is shown that these errors can be reduced by introduction of additional numerical focusing in the tomographic reconstruction algorithm. Additionally, new tomographic reconstruction algorithm using back propagation in reference medium for optical microelements measurement with known design is proposed. This hybrid reconstruction algorithm allows significant extension of ODT applicability in measurement of elements having large deviations of refractive-index distribution.

Problems and Solutions in 3-D Analysis of Phase Biological Objects by Optical Diffraction Tomography

“…This feature is used by Hybrid FBPJ algorithm, in which phase distributions that are focused in the object center, are used for reconstructions. [9,28] The FBPP algorithm is formulated according to the theory of diffraction, however it usually uses an approximated model of the first order Rytov approximation. Therefore, it should deliver a more precise tomographic reconstruction than FBPJ.…”

“…On the other hand it has been proved by many groups that the solution can be provided by combining digital holography with tomographic techniques. The resultant method, often referred to as optical diffraction tomography (ODT), [6][7][8][9] requires capturing multiple complex object fields for different illumination directions with respect to the sample and later tomographic reconstructing of a three-dimensional distribution of refractive index. The accuracy of a 3-D reconstruction depends on several features of an object and data gathering system.…”

Optoacoustic response of gold nanorods in soft phantoms using high-power diode laser assemblies at 870 and 905 nm

“…Ultrasonic imaging has high resolution combined with a high penetration depth, but the contrast between the tumor and the healthy tissues is not appropriately enough [6]. Optical imaging offers good spatial resolution but is limited to a few millimeters in biological tissues [7]. In this regard, optoacoustic tomography (OAT) and microscopy (OAM) have been developed as non-invasive alternatives to the existing imaging techniques, due to their ability of acquiring high-resolution images from deep tissues by using non-ionizing laser radiation [8,9].…”

Influence of tapering process on changes of optical fiber refractive index distribution along a structure

“…According to the investigation presented in Ref. 17, the accuracy of reconstruction of the refractive index distribu− tion in the cylindrical structure with axial symmetry is ap− proximately 10 -4 with the spatial resolution (for the applied magnification of the imaging system) of 0.5−μm order. As mentioned above, the application of Abel tomographic re− construction requires a low noise input phase map.…”