2025, 28 December All-Russian Research Institute for Optical and Physical Measurements (VNIIOFI) is sixty. For this period Institute carry out many scientifi c researches, work out and supplied consumers thousands high-precision measurement technics (inclusive metrology standard equipment). The most significance for optical and physical measurements results of institute researches for period 2016–2025 presents in this article.

Different methods and means of polarization mode dispersion unit reproducing and transmitting in optical fiber for a wide spectral range are considered. The obtained research results made it possible to improve the State primary special standard of the unit of polarization mode dispersion in optical fiber GET 185-2010 and to approve the State primary special standard of the unit of polarization mode dispersion in optical fiber GET 185-2025, which provides reproduction and transmission of the specifi ed unit by polarimetric and interferometric methods in the required spectral range of 1260-1650 nm. A method for transmitting small values (less than 5 ps) of the polarization mode dispersion unit from GET 185-2025 to high-precision polarization mode dispersion interferometric measuring instruments with broadband optical radiation sources is proposed. The development results of optical spectrum analysis set-up are presented. The set-up is included in the GET 185-2025 and it is used for characterization of broadband optical radiation sources used in high-precision polarization mode dispersion analyzers. 

The etalon international comparisons result in terms of the polarimetric method of the unit reproducing are presented. The updated composition and metrological characteristics of the GET 185-2025 are given. GET 185-2025 metrologically provides fi ber optics in both manufacturing and scientifi c and technical fields.

When developing and certifying laser radiation sources, it is necessary to know the characteristic that determines the similarity of the spatial distributions of the emitted beam intensity to a Gaussian distribution. The well-known numerical measure М ² serves as such a characteristic. However, in practice, to expand our knowledge of laser beam parameters, additional measures are required to assess the similarity of the spatial distribution of its intensity not only to a Gaussian distribution, but also to an arbitrarily specifi ed distribution. The authors previously developed identifi cation methods based on such measures, which make it possible to eliminate the shortcomings of the М ² measure. To confi rm the correctness of the theoretical conclusions, four methods for identifying the spatial distributions of the laser beam intensity of the LS-2131M-10-SHG-MN solid-state pulsed laser source (Belarus) were experimentally evaluated. The spatial distributions of the emitted beam intensity are compared with a Gaussian intensity distribution. Using the proposed additional measures, unlike the М ² measure, it is possible to perform identifi cation in real time. The experiments utilized a prototype of a laser beam intensity spatial distribution measurement instrument developed at the All-Russian Research Institute of Optical and Physical Measurements. It utilized a Contrastech Mars 4100-904100-90 multi-element measuring transducer (China) and a computer with integrated laser beam spatial distribution identifi cation software. Experiments demonstrated that the identifi cation measures are highly sensitive to changes in the spatial distribution of laser beam intensity and can be a useful tool for real-time tuning of laser sources.

The problems of metrological assurance for measuring the refractive index of solid optical materials (silicon, germanium, etc.) used in the infrared range of the spectrum (infrared materials) are considered. The refractive index of optical materials in the infrared wavelength range must be known with high accuracy when developing optics for thermal imagers, night vision devices, etc. Currently, the tasks of developing domestic instruments for measuring the refractive index in the infrared region of the spectrum and analyzing measurement errors are relevant. The scheme of the developed infrared refractometer based on a goniometer is presented. Using this refractometer, the method of the minimum deviation for refractive index of infrared materials measurements in automatic mode is implemented. The error of measuring the refractive index of infrared materials by the method of minimum deviation using a developed infrared refractometer based on a goniometer is analyzed, considering the infl uence of measurement errors of the prism angle, beam deviation angle, radiation wavelength and temperature. The infl uence of diffraction on the measurement error of the deviation angles of infrared radiation is considered. The total error of refractive index measurements in the ranges 3–5 and 8–12 microns for germanium and silicon was estimated, which was 4.1·10^–5 and 2.5·10^–5, respectively. The results obtained are important for developing requirements for the components of the State Primary Standard of the Refractive Index Unit GET 138-2021 when improving it in order to expand the wavelength range to the middle and far infrared ranges.

The development of fi ber-optic communication and data transmission systems gives rise to a number of new challenges, among which information protection against unauthorized access is of particular relevance. In response to this need, quantum cryptography has emerged – optical cryptographic systems with quantum key distribution. Such systems protect communication channels by encrypting data with a one-time secret key. The theoretical foundation guaranteeing secure key transmission relies on the Heisenberg uncertainty principle and the no-cloning theorem for quantum states of elementary particles. However, real-world quantum cryptography systems exhibit vulnerabilities stemming from imperfections in their components. Single photon detectors and single photon sources are critical elements of quantum key distribution systems. This work analyses the main types of attacks on quantum cryptography equipment and identifi es the key parameters of single photon sources and single photon detectors.

Knowledge of their actual values can be crucial for proving a system’s resilience against attacks. Additionally, the paper describes the equipment and methods used to study single-photon sources. The study also describes the method and results of investigating the quantum effi ciency and false trigger probabilities of gated single-photon detectors with fi ber input. The described measurement methods are harmonized with the recommendations of the European Telecommunications Standards Institute. Together, the described measurement techniques and setups enable the assessment of single photon source and detector parameters during expert evaluation of quantum cryptography system vulnerabilities. The paper concludes with a call for the establishment of a reference database to support metrological assurance of key parameters for single photon sources and receivers, in order to advance quantum cryptography systems

The results of creating a system for metrological traceability of the results of measurements of the meteorological optical range by transmissionmeters and nephelometers to the state primary standard in the Russian Federation are presented. To solve the problems of realization, maintenance and dissemination of the unit of luminous transmittance to meteorological optical range meters by the transmissometer method, a specialized spectrophotometric facility equipped with a set of large-diameter (140 mm) standard neutral light filters has been developed and created. The created facility is included in the State primary standard of units of color coordinates, chromaticity coordinates, and luminous transmittance, GET 81-2023. Meteorological optical range characterizes the visibility range in the atmosphere, due to the absorption and scattering of optical radiation. The value of meteorological optical range is directly related to the luminous transmittance of atmospheric air. 

Thus, the unity of measurements of meteorological optical range must be ensured by the traceability of the meters of the luminous transmittance coeffi cient of atmospheric air to the State Primary Standard. The facility realizes the unit of luminous transmittance in the absolute value range from 0.027 to 0.993 with combined standard uncertainty of 0.00042. Large-diameter standard fi lters allow to disseminate the unit of luminous transmittance to transmissometers intended to measure the luminous transmittance of atmospheric air in natural conditions and realize the scale of meteorological optical range. The nephelometric measurement method and the dissemination of the unit of meteorological optical range to nephelometers are described. The created facility heads the State Verifi cation Scheme and ensures traceability to GET 81-2023 of meteorological optical range measuring instruments used in meteorology, air travel safety systems, shipping, and road management.

The results of research on an experimental sample of a quantum matrix sensor created using hybrid technologies and designed to solve low-photon problems are presented. Hybrid technologies combine the functionality of vacuum electron-optical converters and silicon matrix photosensitive devices. Electron-optical converters provide a high brightness gain of optical radiation with a low noise level, and matrix photosensitive devices provide a high level of processing of the spatial brightness distribution of optical radiation. Combining these capabilities allows photonics tools to advance into the low-photon fi eld. Hybrid quantum matrix sensors allow measurements to be performed in the photon counting mode, i.e., to measure the parameters of objects from which a countable number of photons enter the sensor. This signifi cantly expands the possibilities of photonics in medicine, biology, astronomy, remote sensing of the Earth, quantum communications, etc.

Optical nanosensors convert changes in the properties of nano-objects placed in the test medium and interacting with the molecules being analyzed into analytically useful information. This information includes the characteristics of light emission and their changes due to various optical effects (absorption, fl uorescence, elastic and Raman light scattering, etc.). The main advantages of optical nanosensors are the simplicity and rapidity of analysis, low cost, and the ability to be used directly at the sampling site. The use of optical nanosensors opens up new possibilities in clinical laboratory diagnostics, including personalized medicine, food and food raw material monitoring, and environmental monitoring. The operating principles of nanosensors based on dynamic light scattering are considered. New approaches for nanosensor design developed at All Russian Scientifi c and Research Institute for Optical and Physical Measurements (VNIIOFI) are described. These approaches reduce the size of nanoparticle aggregates with increasing analyte concentration (sensor for an antibiotic in milk and water) or utilize the combined use of static and dynamic light scattering (a sensor for a fungal pathogen). The operation principles of nanosensors based on fl uorescence effects are presented. A nanosensor developed for glutathione (a compound that plays an important role in protecting the body from oxidative stress) is presented. This nanosensor utilizes the analyte-induced reduction of quenched fl uorescence in quantum dots. Prospects for the application of the obtained results and the further development of optical nanosensors are discussed.

Ensuring the uniformity of measurements of pulsed electromagnetic factor parameters is critical for improving the reliability of interference immunity testing of aviation, rocket and space equipment, and information and communication technology equipment. This article provides an overview of electromagnetic pulse measurement instruments used in the Russian Federation, indicating their types and main metrological characteristics. Traceability of these measurement instruments to state primary standards of units of pulsed electric and magnetic field strengths, high pulsed electric voltage, and pulsed current is ensured. A comparative analysis of the state of metrological support for pulsed electromagnetic fields, currents, and voltages in Russia and abroad is conducted. The paper formulates key areas for improving the reference base for the metrological support of prospective types of pulsed electromagnetic field measurement instruments. The choice of a pyramidal TEM-cell (GTEM-cell) as a field-generating system of standard facilities for reproducing long-duration pulsed electric and magnetic fields with rise times in the tens of picosecond range is justified. Its geometric parameters and structural elements are calculated, and the amplitude-time range and uncertainty of unit reproduction are estimated. Standardizing the dynamic performance error of measuring instruments in the picosecond range has been identified as a prospective direction for further research in ensuring the uniformity of pulsed electromagnetic field measurements.

The metrological support for physicochemical measurements of the compositions of materials containing rare and rare-earth metals is considered. Special attention is paid to the role of standard samples of the composition of substances and materials in ensuring the uniformity of measurements in spectral studies.

A methodology for the development of reference materials using State primary standard for units of mass (molar) fraction and mass (molar) concentration of components in liquid and solid substances and materials based on spectral methods GET 196-2023 equipment is described. As a result of the work, 16 standard samples of the composition of rare and rare-earth metals of the approved type have been developed, and their metrological characteristics are given. The high accuracy of measurements of the characteristics of reference materials provided by the use of GET 196-2023 is shown. Metrological support for analytical control of rare and rare-earth metals is of great practical importance for the development of industry, scientific research, and product quality assurance. Therefore, the results of this work are relevant for ensuring the traceability of physical and chemical measurements in various fields of science and technology, including metallurgy and chemical industries, medicine, environmental monitoring, electronics and information technology, the energy sector, the defense industry, the aerospace industry, and others.