Abstract. A method is proposed to increase the size of enlightenment area defined as the ratio of the radius for the optical element surface, where the reflection is less than a certain value, to the element radius. The increase is achieved due to the use of a circular diaphragm, located between the evaporator and the substrate, which shields a part of the evaporated molecular flow and redistributes it over a specified por-tion on surface of the optical element. It is shown that the size of the enlightenment area increases by 17% when a single-layer antireflection coating with refractive index ni = 1,35 is formed on the surface of large-curvature optical element (radius R = 10 mm) made of a material with the refractive index nm = 1,52. Analysis of factors influencing the size of the enlightenment area is carried out for the case when a circular diaphragm is used, and distribution of the reflection coefficient of single-layer antireflection coating over the surface of large-curvature optical element is demonstrated. 

Keywords: anti-reflective coating, area of enlightenment, large-curvature optical detail, diaphragm

References:

1. Gubanova L.A., Khoang Long Tkhan', Do Tay Tan, Scientific and Technical Journal of Information Technologies, Mechanics and Optics, 2015, no. 2(15), pp. 234–240. (in Russ.)
2. Gubanova L.A., Khoang T.L. Journal of Instrument Engineering, 2016, no. 10(59), pp. 860–866. (in Russ.)
3. Gubanova L.A. Gradientnye interferentsionnye sistemy (Gradient Interferential Systems), Doctor’s thesis, St. Petersburg, 2008, 243 р. (in Russ.)
4. Gubanova L.A., Putilin E.S. Journal of Optical Technology, 2008, no. 4(75), pp. 278–281.
5. Dmitrenko V.A. Tekhnologiya polucheniya tonkoplenochnykh pokrytiy s peremennym otrazheniem (Technology of Receiving Thin-Film Coverings with Variable Reflection), Candidate’s thesis, St. Petersburg, 2003, 153 р. (in Russ.)
6. Tomofuji T., Okada N., Hiraki S., Murakami A., Nagatsuka J. Optical Interference Coatings, OSA Technical Digest Series, 2001, Art. MD2.
7. Putilin E.S. Gubanova L.A. Opticheskie pokrytiya (Optical Coating), St. Petersburg, 2016, 268 р. (in Russ.)
8. Baumeister P.W. Optical Coating Technology, SPIE Press monograph, 2004, 840 p.
9. Kuzin A.A., Zablotskiy A.V., Baturin A.S., Lapshin D.A., Melent'ev P.N., Balykin V.I. Nanosistemi, Nanomateriali, Nanotehnologii, 2009, no. 1(7), pp. 163–168. (in Russ.)
10. Petukhov V.Yu., Gumarov G.G. Ionno-luchevye metody polucheniya tonkikh plenok (Ion-Beam Methods of Receiving Thin Films), Kazan', 2010, 87 р. (in Russ.)
11. Borisenko V.E., Vorob'eva A.I. Nanoelektronika (Nanoelectronics), Minsk, 2003, Part 2, 77 р. (in Russ.)
12. Macleod H.A. Thin-Film Optical Filters, Boca Raton, FL, CRC Press, 2010, 800 p.
13. Herzig H.P. Micro-Optics: Elements, Systems and Applications, CRC Press, 1997, 600 р.
14. Holland L. Vacuum Deposition of Thin-Films, Chapman and Hall, London, 1966.
15. Gubanova L.A. Journal of Optical Technology, 2008, no. 4(75), pp. 87–91. (in Russ.)