Recently, three-dimensional (3D) super resolution imaging of cellular structures in thick samples has been enabled with the wide-field super-resolution fluorescence microscopy based on double helix point spread function (DH-PSF). However, when the sample is Epi-illuminated, much background fluorescence from those excited molecules out-of-focus will reduce the signal-to-noise ratio (SNR) of the image in-focus. In this paper, we resort to a selective-plane illumination strategy, which has been used for tissue-level imaging and single molecule tracking, to eliminate out-of-focus background and to improve SNR and the localization accuracy of the standard DH-PSF super-resolution imaging in thick samples. We present a novel super-resolution microscopy that combine selective-plane illumination and DH-PSF. The setup utilizes a well-defined laser light sheet which theoretical thickness is 1.7μm (FWHM) at 640nm excitation wavelength. The image SNR of DH-PSF microscopy between selective-plane illumination and Epi-illumination are compared. As we expect, the SNR of the DH-PSF microscopy based selective-plane illumination is increased remarkably. So, 3D localization precision of DH-PSF would be improved significantly. We demonstrate its capabilities by studying 3D localizing of single fluorescent particles. These features will provide high thick samples compatibility for future biomedical applications.
X-ray phase-contrast imaging is an important diagnostic tool in medicine, biology and materials science. In-line hard x-ray phase-contrast imaging is based on Fresnel diffraction of x-ray, therefore we propose to make phase retrieval calculations between arbitrary planes interrelated through the Fresnel domain. A new approach to the numerical reconstruction of object phase by the diffraction intensity for in-line x-ray phase-contrast imaging is presented. The new method is tested on simulated image and the results demonstrate the validity of this new approach.
In order to implement 3-D imaging of objects with large height discontinuities and/or surface isolation, we present a novel 3-D imaging system based on temporal sequential fringe projector to provide multi-resolution 3-D reconstruction. To recover the range data of such a surface, an enhanced scheme for temporal phase unwrapping procedure is proposed. We also describe methods for extracting the color texture corresponding to a range image. Experimental results are given to illustrate the validity of our proposed method.
In the spectrum range of middle wave infrared region (MWIR) and the long wave infrared region (LWIR) radiation, the infrared spectral imaging technology is far from mature in comparison with its counterpart in visible region because infrared radiation is relative weak, the corresponding solid-state detectors and dispersive elements are extremely expensive. The paper reports a novel configuration that exploits the abundant chromatic aberration of binary optical lens to create a dual band infrared imaging imager. The design method of spectrum-dividing systems is presented for infrared imaging spectrometer. The system was analysed and evaluated by optical design software ZEMAX, theoretical formulas were then established. The practical design shows that the system has the very simple optical design that enables a very low cost lightweight robust dual band infrared imaging spectrometer.