Cutting‑edge optical technologies

1. Design

Lobre mainly uses ZEMAX OpticStudio software for the design of optical systems.

For the optomechanical part, we primarily employ SOLIDWORKS CAD software.

2. Lens Generation

The generation of lenses and optical components takes place through cutting and shaping of optical glass with various machines, such as rounding machines and CNC twin‑spindle machining centres fitted with air bearings to reduce vibration effects.

These machines allow the production of objects with very tight mechanical tolerances, typically within one hundredth of a millimetre.

Lobre also has a new SatisLoh 5‑axis multifunction machining centre capable of generating highly precise spherical, aspherical, toroidal and cylindrical elements in a large size (up to 300 mm in diameter). This machine also enables the creation of free‑form optical glass objects and is equipped with an internal CMM measurement system.

3. Polishing

Traditional Polishing:

This process requires considerable skill and craftsmanship to achieve extremely low surface roughness and high flatness.

Indeed, traditional pitch‑lap polishing is a manual technique capable of delivering high‑precision optics, carried out by lapping with hand‑cast semi‑malleable pitch and grooved to retain a fine abrasive mixture. More specifically, this method involves pressing the optical piece against the pitch lap on a single‑flip polishing machine.

This polishing method makes it possible to produce components with excellent finishes; however, the process is much longer and less predictable than CNC‑controlled polishing.

Numerical Control Polishing [CNC]:

Since the 1990s, Lobre has made significant investments in innovative CNC machines capable of uniformly and very precisely polishing various optical components. This marked a turning point in significantly improving the quality of the manufactured components.

4. Centring

The centring phase is the penultimate step in the process: its purpose is to ensure that the optical axis is perfectly aligned with the rest of the optical component. For this reason, the lens is initially produced slightly oversized and, during centring, its edge is precisely reshaped.

Lobre has the latest generation CNC centring machines capable of:

• redefining the edge of the lens,
• applying protective bevels,
• handling the creation of free-form glass components.

Centring accuracy can be guaranteed, depending on the type of component, up to 10 Arc seconds.

5. Coating

Lobre has been performing coatings in-house for over 50 years. In recent years, we have invested significantly in this department, which is now located in a facility equipped with two cascading ISO Class 7 cleanrooms, staffed by 4/5 dedicated personnel.

Within our coating department, in addition to standard recipes, we carry out thin-film coating engineering projects, i.e., the service of designing and optimising custom coating recipes, etc.

Lobre’s coating activity falls under the techniques known as Physical Vapour Deposition (PVD): this is a well-established and developed technique that permits thin (and other) films to be deposited under vacuum, often achieved by atomic growth on a specifically prepared/masked substrate (the object to be treated).

In practice, this atomic deposition process allows for the controlled evaporation of a target material, which is then transported from the solid source in vapour form through a vacuum environment (10⁻⁶) to the substrate where it condenses.

The generation of coatings using Electron Beam PVD takes place through the evaporation of metals/materials that compose the coating layer with extreme precision. The transport from the sources, called Targets, to the parts to be coated occurs via vapour or plasma (i.e., an ionised gas at low pressure generated by several ion guns (e-guns) used simultaneously, supported by a very powerful Plasma source).

The use of a high-power Plasma source together with multiple ion guns for evaporation allows for the creation of precise, compact, and durable layers. In particular, the advantage of this technology is that the evaporated atoms have an energy distribution mainly dependent on the temperature of the source, thereby reducing the number of high-energy atoms that could damage the product/substrate.

6. Assembly

The assembly of various systems takes place in laminar‑flow hoods or in an ISO 7‑class cleanroom.

We also have a darkroom available for conducting assembly tests and analyses in the absence of stray light in order to optimise the delicate assembly phase.

7. Quality Control

The final phase in the production process involves the final evaluation of all the technical factors that may characterise each individual component or system produced at Lobre. For every component, all the parameters and tolerances required by the technical drawing are recorded: specifically, everything is meticulously measured in the inspection room, where state‑of‑the‑art equipment enables us to certify the achievement of the standards required by the client.

This next‑generation equipment includes:

• Optotech OWI 150 interferometers with Zygo MetroPro™ and OWI XT INVERS, with Zygo MX™,
• Agilent Cary 5000 spectrophotometers with UMA system, Shimadzu and Filmmetrics F10ARC,
• Zygo ZeGage Pro HD optical profiler and roughness meter,
• Spherometers,
• Trioptics Opticentric™ with Optisurf™ and Optispheric™ to verify optical centration and to evaluate the performance of industrial lens‑and‑objective assemblies or optical systems (EFL control, MTF).

In particular, the Trioptics Optisurf™ equipment enables a very in‑depth performance analysis, verifying for each single surface of a system its positioning/tilt within the assembled system (System performance evaluation).

Moreover, thanks to a highly sophisticated custom‑developed ERP system, we are able to monitor and record all the information relating to the optical components and systems produced at Lobre throughout their production cycle, from the origin of raw materials through to final delivery to the client. This allows us to guarantee full traceability and to provide comprehensive reporting on all parameters checked during production and in the final quality‑control phase.