Abstract. The paper deals with the problems of development and designing of microprojection system of mixed and augmented reality designed so that an observer could see the information of the microdisplay and the surrounding space as the background at the same time. The combiner on planar waveguides screens based on the composite structure of the prism elements was developed. In this work different results of the simulation with the TracePro software are considered and also the main problems encountered in the development of such systems are considered. IntroductionIn the last decade in patent literature and articles a lot of information about the input image systems in the observer's eye from the reflective microdisplays can be found. Such systems consist of the image generator (most often it's the microdisplay with the illumination system if the display is not selfluminous), the lens that forms an image at infinity and the combiner which creates the required field of view and ensures the formation of images in the form of a raster-character information on the retina at the background of the surrounding space [1]. Field of application of such systems is quite wide: civil and military avionics, training systems, automobile production, etc.The present work is devoted to the development of new methods of calculation and design of microprojection systems of mixed and augmented reality.Among the patent literature the most common method to provide the operation of the combiner is the use of holographic optical elements. However, the reflectivity of the holographic combiners strongly depends on the incidence angle and wavelength, thus limiting the development, primarily color displays [2]. Moreover, most software can not realize the full and correct operation with holographic elements, because there are no exact calculation models and algorithms for solving the ray tracing from the object plane to the image plane. The relevance of the work related to the solution of these problems and is dedicated to the development of calculation models of microprojection display systems.