Essential knowledge (contd): Multifocal and progressive lenses including: appropriate formulae when performing calculations related to multifocal and progressive lenses calculation of fused segment and thickness allowance for manufacturing determining addition powers determining powers from radii determining the prismatic effect of multifocal and progressive lenses differences between bifocals, trifocals progressives, and their methods of manufacturing differences between fused and solid multifocals differentiating styles and types of progressive lenses the range of multifocal and progressive lenses available Ophthalmic prism including: effects of ophthalmic prism upon the eyes, and the need for ophthalmic prism in prescriptions solving by both calculation and graphical methods, a variety of prism problems the relationship between lens power, decentration and prism the use of a tangent scale to measure ophthalmic prism Relevant Australian Standards Scope of metal and plastic frame material including heating, manipulation, adjusting, handling and repair Spherical lenses including: concepts of vergence and demonstration of its use in optical calculations how to construct diagrams to illustrate image formation using simple ray-tracing techniques refractive effects of a lens as the sum of its two surface powers refractive properties of spherical lens surfaces The properties of lens The use of impact resistant protective lenses Types of ophthalmic lenses and spectacle frames and their performance characteristics Vacuum coatings including: absorptive (tinted) coatings handling, cleaning and care of coatings manufacturing processes multiple layer AR coatings single AR coating surface reflections and ghost images |