Precision replication of all types of optical surfaces—scientific and technological basis for the radical transformation of modern optical production

Abstract

Subject of study. The developments and proposed innovations of the Scientific and Production Association “State Institute of Applied Optics” in the field of advancement of precision replication technology of all types of optical surfaces (planar, spherical, aspheric, and freeform) aimed at ensuring the possibility of series and mass production of the so-called combined optical elements (COEs) and the large-scale fabrication of objectives operating in a wide spectral range for various purposes based on these elements are discussed. Aim of study. This study is aimed at the introduction of new proposals for the radical transformation of modern optical production based on advanced precision replication technology of all types of optical surfaces of lenses and mirrors to the Russian and foreign scientific and technological community and the executives and process engineers of optical production facilities. Method. The technology for shaping the working surfaces of optical elements of all types (lenses, mirrors, and prisms) is based on precision replication of their working surfaces using highly precise and certified master details in relatively thin polymer layers on substrates made of glass or other optical materials. The use of cold-curing resins, predominantly photopolymerizable compositions, is advisable. Main results. We demonstrate that a radical solution to the problem of establishing the series and mass production of optical elements with working surfaces of any type can be based on the precision replication technology using cold-curable polymer materials. The COEs obtained using this method comprise a glass base with one or two relatively thin polymer layers that have outer surfaces of a specified shape. Using low-shrinkage cold-curing polymer materials ensures the absence of thermal deformations of the COEs and their high reproducibility in each batch. Such elements have high mechanical, thermal, and optical properties of glass optics, and the cost of their series production is manyfold lower. We established that (when the technological regimen is followed) the replicated surfaces are identical to the working surface of the original master detail in terms of surface shape (N, ΔN), surface finish class (P), and roughness parameters (Rz, Ra). Moreover, the storability and resistance to environmental factors of the COEs are practically equal to those of their purely glass counterparts, which is confirmed by the results of multiple complex tests of different COE types over a period of several years. A hierarchic system of master details comprising reference, control, and working matrices is proposed. The reference matrices must always be produced in pairs of convex and concave matrices (similar to spherical test plates). Practical significance. Owing to a rapid increase in the demand in optoelectronic instrumentation engineering for objectives for different applications in a wide spectral range (smartphones, tablets, digital cameras, video projectors, analytical instruments, thermal imaging equipment, video surveillance and security systems, and spaceborne optical surveillance instruments), there has been an urgent need for a significant increase in the production capacity and cost reduction of the manufacturing of basic optical elements. Precision replication technologies provide the fundamental and practical possibility for solving this problem.