EU hybrid diffractive/refractive lenses
Increased demand for high-performance glass optics has created a trend toward miniaturisation with enhanced function integration and imaging quality. Most EU small- and medium-sized enterprises (SMEs) do not have the infrastructure required to deliver tailor-made optical systems with unparalleled performance and quality. Combining SME expertise can help realise the development of innovative photonics devices previously not possible. The EU-funded project NGOPTICS is working on the development of next-generation hybrid diffractive glass optics with diffractive and refractive components. Scientists will produce a curved glass lens with a diffractive structure added on top of the refractive (curved) surface through the use of precision glass moulding. The identified applications are a novel optical device for measurement of thin-film thickness and a high-quality laser objective for an infrared (IR) laser telescope. Scientists initially focused on definition of the demonstrators, evaluation of mould materials, and development of tools and processing techniques. For the measurement device, the demonstrator is based on the separation of light into different wavelengths. Researchers evaluated the use of different numbers of lenses, materials and geometries. Without diffractive optics, an IR laser telescope requires four spherical lenses. Exploiting diffractive optics enables the use of one spherical lens and one non-spherical or aspheric lens with a diffractive optical element to decrease wave error and increase efficiency. Scientists have explored the moulds for the demonstrators and developed two standardised mould and die concepts. Processing is now focused on development of diamond cutting tools and ultra-fine grinding wheels for the demonstrator manufacturing processes. Hybrid glass optics currently do not exist. NGOPTICS are developing the necessary materials and processing methods to enable EU SMEs to easily and efficiently manufacture two demonstrators of these ground-breaking photonics technologies.
