Optical Finishing

The term “finishing” in the optical industry can be a broad term used to express the final manufacturing processes used to provide a finished, or completed optic ready to be used in the final application.

Most often, a finished optic is either a polished component or a coated component. Machined or molded blanks are often not considered the final finished component as without the further polishing or rather polishing and coating processes typically blanks are not functional enough as is for the majority of end use applications.

We also provide a wide variety of finished stock optics in our online store. Everything from colored filter glass and witness samples to test plate mirror blanks and both laser mirrors and debris shields.

As a vertically integrated manufacturer of optics we have been providing a variety of lens finishing services for close to 50 years now. Contact us anytime to discuss the needs of your next project.

Learn more about both our custom polishing as well as our thin film coating finishing services below.

Thin Film Coating

ULC provides a broad range of optical coating services, ranging from anti-reflection and protected or enhanced metal mirrors consisting of 1-9 layers, to dielectric polarizers and beam splitters consisting of 60+ layers. These coatings can be applied as a finishing service to optics up to 23″ in diameter, having various shapes and sizes, with either plano or curved surfaces. Prior to coating, all optics are either cleaned in one of our automated ultrasonic cleaning systems or hand washed in our class 1000 cleaning and inspection room.

Our coating chambers are equipped with electronic beam guns as well as both resistive and ion sources utilized in IAD coatings. The entire deposition process is computer controlled to ensure repeatability, while the layer thickness is precisely achieved through a combination of crystal or optical monitoring. All of our coating chambers are additionally equipped with cryogenic pumps to minimize the risk of contamination.

To verify spectral performance, our spectrophotometers have various attachments enabling measuring of a witness sample in transmission and reflection with S or P linear polarized light, as well as unpolarized light. We also utilize in-house abrasion, adhesion, high/low temperature, humidity and salt fog capabilities for further testing options. Coatings can also be tested to a variety of military or ISO specifications onsite with our regularly calibrated equipment, with standards and apparatus having NIST traceability.

When our military customers need a coating that can survive an atypical or harsh environment, they come to ULC. Our home grown techniques, coupled with the latest technology and our extremely talented coating team, help us achieve and prove that our coatings are some of the best in the world.

View the reflectance curves below for a look at our standard coating offerings.

Reflectance Curves for AR Coatings
Reflectance Curves for Standard Metal Coatings @ 45 Degrees AOI
Reflectance Curves for Standard Metal Coatings @ 8 Degrees AOI


Our key to providing you with precision begins with our employees. Our highly trained opticians and operators are polishing components in any quantity you need. Our cutting edge machinery and investment in technologies allows our operators to provide you with components up to 18 inches in diameter, with additional lens finishing capabilities that can provide surface flatness to 1/20 wave P-V @ 632.8nm, with parallelism < 1 arc second. Our surface roughness quality can also be extremely low angstrom—so ask us about your next low angstrom project.

Some of our customers require additional finishing services beyond the more standard top and bottom surface polishing, such as polished edges and bevels. ULC has stepped up as a leading lens finishing manufacturer to meet that challenge developing custom equipment and processes to keep costs as low as possible for these types of projects. When we focus on continuous improvement, our customers win in the end.

Our newest capability includes our MRF finishing, a newer technology that involves polishing slurry being magnetically controlled in real time—the finished product meeting or exceeding specifications. Read more about the benefits of the Magneto-Rheological Finishing (MRF) process.

To ensure each product meets customer specifications, components are tested using state-of-the-art interferometers, polarimeters, autocollimators and many other optical gaging instruments where appropriate. Check out our quality information to learn more.

To get started with us on your next project, please fill out the form below. We will reply as soon as possible.