# Metrological Analysis of Integrating Sphere Photometers for LED Luminous Flux Measurement

A comparative metrological analysis using mathematical models of three integrating sphere photometer schemes, for LED luminous flux measurement, was held. Each model takes into account the main design parameters of the photometer, typical values of which are used in the calculations.

# The Theory of Forming the Illumination Field on the Inner Surface of an Integrating Sphere of Photometer for Luminous Flux Measurement of the LEDs

Simplified mathematical models of the formation of the illumination field on the inner surface of the spherical photometer for three common schemes of constructive placement of the LED were proposed. The models are based on a combination of the method of successive reflections with the integration of illumination of rings around elementary segment symmetrically illuminated by LED. Each model takes into account the main design parameters of the photometer, which affect the level of light reflectance of the inner coating, and spatial orientation of the indicatrix of LED sources.

# Metrological Characteristics of a Diffuse Emitter Based on the Integrating Sphere with Light-Emitting Diodes

The aim of this work is developing, with the help of the developed numerical method, analyzing the impact of the main elements of DV on its metrological characteristics and development on this basis, recommendations for designing next-generation high-precision IS. To identify the main parameters of a spherical surface that affect on formed brightness field.

# The Numerical Method of Analysis of the Diffuse Emitter Intensity Based on the Integrating Sphere

This paper develops a novel numerical method for the analysis of the diffuse transmitter based on the integrating sphere, which allows evaluating the parameters of the field formed by the emitter brightness taking into account the effects of micro- and macrostructure and its sources of radiation. The method is based on the geometrical ray propagation laws in the space, their specular and diffuse reflection on surface of the sphere and its elements such as the hump, pit, fence, patch.

# 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.

# Metrological analysis of the diffuse light source of variable brightness based on conjugate integrating spheres

The paper highlights theoretical analysis of accuracy of the diffuse light source of variable brightness based on conjugate integrating spheres. We develop the calculation procedure of its accuracy when the design parameters are modified. In addition, we give some recommendations on designing the diffusive light source to provide necessary stability of brightness in the output aperture.

# The approaches, means and metrological assurance of calibrationof the standard radiators

We consider the approaches and means of calibration of the standard radiators for precision photometric equipment. Moreover, we develop the engineering approaches and recommendations on choosing the primary elements of the equipment.

# Diffuse light source with variable radiance for calibration of precise digital video systems

This study provides insights into a new scheme for measuring radiant characteristics and calibration of precise digital video systems, based on the original diffuse light source with variable radiance. This source provides better metrological characteristics of the calibration of new generation of digital spacebased video systems of high definition. We also analyze the types of the inner surface coating of the source. Different variants of light sources were reviewed and just miniature tungsten halogen lamps