Even a tiny particle will cause failure of the coating. Therefore, all of our filters are manufactured in the cleanroom that occupies up to 2000 square meters. Cleanroom is the fundamental for a making a good quality filter.

KUPO Dichroic Filter: Facilities Cleanroom

Coating Chambers

Our coating chamber is 1.7 meter height and diameter 1.5 meter inside.The coating thin-films are formed by evaporating the coating materials in a vacuumed chamber. With Ion Assistant Deposition (IAD), the thin-films will firmly attach to the glass substrates with great density.

The glass substrates are placed in the planetary rotating trays on the same horizontal level. This helps the evaporated coating materials evenly attach to the glass substrates which guarantees consistency of optical specification.

KUPO Dichroic Filter: Facilities Coating Chambers


Cleaning is also a critical process during manufacturing. All substrates are cleaned by ultrasonic cleaning machine to ensure coating thin-films firmly attach to them. Filter will be cleaned again after coated in order to ensure the clean surface while delivery.

KUPO Dichroic Filter: Facilities Cleaning



With great cutting capability, we are able to provide the filters in various shapes. The original sheet is a large plate with diameter 450mm. By using precision linear cutting or more precise laser cutting, we are able to provide filters in any size, any shape.

KUPO Dichroic Filter: Facilities Cutting


A spectrometer is necessary to ensure the optical specification meeting the requirement. All coated filter will be inspected by the spectrometer before being shipped to our customer or put in stock. The filters will be scanned again before shipment in order to deliver the right product to customers.

KUPO Dichroic Filter: Facilities Spectrometer

Surface Inspection

Customers who apply the filter in a precise instrument usually require filter with great surface quality. To prevent the severe surface issue, we use precise inspection instrument to mark out the unacceptable scratch and dig, and make the filter delivery conform to the specification.

KUPO Dichroic Filter: Facilities Surface Inspection