Instrument-making and information-measuring equipment

Development of Calculation Methods of Diffractive Lenses

The purpose of this paper is to develop the calculation method of diffractive lenses with the given transmittance that allows determining structural parameters of diffractive lenses. To this end, we employ the example of one of the options of lenses transmittance. We show that the lens with the same parameter works as a Fresnel zone plate. In addition, we analyze the intensity distribution generated by this plate was analyzed. We show that with the increase of a focus number the focus intensity decreases, while the highest intensity is observed for the main focus.

Monochromatic Aberration of Kinoform Element

Based on the aberration model of thin lens, we obtain the monochromatic aberrations of the paraxial kinoform element with a high efficiency in the first diffraction order. We consider the dependence of field aberrations from the aperture position. Moreover, we determine the conditions, under which the kinoform element is free from some aberrations. We also study the conditions of the variation range of each field aberration minimum in the spectral range of 8–12 microns for the element with specific design parameters.

Metrological Analysis of the Diffuse Transmitter Based on the Integrating Sphere with Light-Emitting Diodes

This paper highlights the metrological analysis of the diffuse transmitter based on the integrating sphere with the cosine radiation sources. We propose novel simplified calibration methods of diffuse emitters.

Theory of the diffuse transmitter on the basis of an integrating sphere with light-emitting diodes

We develop a theory of the diffuse source with cosine radiation sources which allows describing the formation of the brightness field in the output aperture in a first approximation. We obtain the engineering formulas and also recommend how to calculate and to design a diffuse source with specified parameters.

A novel optical distal instrument for minimally invasive clinical medicine

The paper proposes two models of the novel midget optical distal instrument (ODI) for clinical use. These ODIs can function with standard endoscopic and laparoscopic equipment through their instrumental channels. Contact Taper-M ODI eliminates the optical radiation leakage through its side nonfunctional surfaces to minimize the radiation injury of sound tissues adjacent to the operation zone.

Permissible Errors of the Eye Aberrometry

This paper investigates the influence of the human eye’s aberrations on a diffraction image of two points at the retina. These points are located at spatial resolution threshold according to the Raleigh’s criterion. The diameter of a pupil zone was set to 3 mm, at which the eye has the highest sight acuity. We determine that in order to preserve normal spatial resolution of the eye the wavefront RMS of the eye should not exceed 0?1 of the wavelength. Based on this thesis, the criterion is proposed to evaluate permissible errors of eye aberrometry.

Three-Dimensional Tomography Reconstruction of “Large” Objects Using Partial Scans

In this paper, we investigate the issues of the tomographic reconstruction of “large” objects. Moreover, we separately consider the reconstruction of objects larger than the size of the CT matrix detector in the horizontal and vertical planes. Using the interpolation methods, we present the mathematical apparatus of synthesis of the complete projection data from projection data of partial scans of individual sections. We propose novel three-dimensional tomographic reconstruction algorithms based on the intersection scans scheme for the research of “large” objects.

Determination of spatial resolution of the space scanner

In this paper, we propose to determine spatial resolution of the space scanner when the image contrast, formed by the objective lens–CCD-array’s system, is decreased twice. The obtained expression enables calculating spatial resolution of the space scanner. In this expression the modulation transfer function of the objective lens is represented by an experimentally obtained separate point. Furthermore, the influence of the pixel size of the CCDarray on spatial resolution of the scanner is studied.

Clinical apparatus for photodynamic diagnosis of early cancer

In this paper, we investigate the technique for fluorescence diagnosis using the Ukrainian “Hyperflav” photosensitizer to differentiate healthy and affected sites of internal organs’ mucosa in the real time mode. It makes for providing an early treatment to prevent degeneration of these sites into oncological diseases.

Designing of the optical system for the thermal imager

The paper presents a method of designing of the optical system which provides set characteristics of the thermal imager. Crucially, we illustrate a sample of calculation of a FOV, a focal length, an entrance pupil diameter and the angular resolution of the objective.