Spherical Plano Lenses, Mirrors, Windows – Faster with Improved Quality with Diamond-pallet Grinding

Published: January 5, 2023

A shorter lead time is perhaps the third most important criterion (two others are capabilities and price) when it comes to ordering custom optics products, such as mirrors, windows, blanks, lenses (also spherical plano lenses) and prisms. In some market situations, such as we observe in 2021 and 2022, the lead time prevails over price.

Solaris Optics, a manufacturer of precision optics elements, finds shortening lead time as one of priority development areas, next to quality and technical capabilities. In the following article we refer to findings from our recent investment in new grinding capabilities.

New Grinding Technique for Improved Quality

With technical capabilities, quality and lead time development as the main goals, Solaris embarked on an investment project aimed at development of R&D infrastructure, back in 2019. The project assumed purchases of various equipment, including one-sided automated grinders along with a set of diamond pallets. The project resulted in several R&D projects and developments in Solaris Optics, as described in detail in our earlier publications, such as Subsurface Damages Reduction for Precise Optics Manufacturing or Raster Mode to Expand Capabilities of Magnetorheological Finishing.

In regards to automated grinding with diamond palettes, Solaris Optics engineers assumed that adding the method to company manufacturing portfolio will allow to speed up optical grinding and polishing phases. The shorter process time shall be possible by higher efficiency of grinding, but also by keeping the subsurface damages minimized, which shall allow to reduce the polishing time needed to reach the required surface quality of optical elements.

The machine was turned into use in 2021 and quickly proved the reduction of sub-surface damages.
Then it was further tested to understand how the new process can affect the overall manufacturing speed. As explained in the aforementioned article it was expected that “the main benefits for clients include shorter lead times and lower costs with improved final product quality (i.e. less scatter, better durability).” After about 1.5 years after implementation we can announce some conclusions from the investment.

Spherical Plano Lenses – Surface Process Time Down by 40%

Our technology team tested and compared production times of 11 different optical products using a traditional process and a new one, which included the new grinding method. The tested products were of various sizes, materials and types, such as spherical plano lenses, mirror substrates, optical windows and filters. Materials included e.g. borosilicate crown glass, crown type Soda lime glass, Quarz and filter glass.
With the new technique the team managed to significantly speed up the grinding times, whereas the overall gain on grinding + polishing time was reduced by over 42% on average (37% to almost 50%), with many dependencies between product characteristics and processing time uncovered. The exercise proved not only the efficiency of grinding with diamond-based pallets, but also that, there is shorter polishing time needed due to reduction of sub-surface damages at the earlier stage.

Higher Speed, Quality and Increased Competitiveness

The investment in automated grinding with diamond palettes proved successful in the assumed goals, i.e. shortening lead times and improving product quality. Apart from the tested product types, i.e. windows, mirror substrates, filters and sphetical plano lenses, the technology process and it’s gains are applicable also to other precision plano optical elements as well as to prisms.
The new production machinery enables further improvement of Solaris Optics competitiveness and the existing clients already benefit from the advantages. In the future Solaris plans to complement the technique with spherical grinding possibilities.

Should you be interested to cooperate with Solaris Optics, please do not hesitate to contact us.
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The diamond grinding investment is a part of a project titled Development of R&D infrastructure of Solaris Optics S.A. as a way to implement innovation, realized by Solaris Optics with financial support from the European Regional Development Fund under the Regional Operational Program of the Mazowieckie Voivodeship for 2014-2020, Sub-measure 1.2. Research and development activities of enterprises.