Your requirements. Our expertise.
At bk Interferenzoptik, we offer standard products and custom optical coatings tailored to your requirements and built for industrial use. From single pieces to large production runs.
Find the right optical solution with us
Looking for a filter, a special coating or help with an optical service? We will discuss your application and work with you to find a solution that meets your requirements.
A short description of your idea is a good starting point. If you already have specifications or drawings, please attach them to your email.
Contact us directly
Whether you have an initial idea or a detailed specification, we will personally help with your product or service enquiry.
Simply give us a call or send us an email.
Checklist for your enquiry
Our glossary explains the key terms for optical filters and coatings: Explore the glossary.
Spectral selection
- Center wavelength (CWL): ... nm / ± Tolerances (from +5 nm to −5 nm)
- Desired wavelength in nm at the center of the passband.
- Full width at half maximum (FWHM): ... nm / ± Tolerances (from +5 nm to −5 nm)
- Desired bandwidth in nm, measured at 50% of the maximum transmission.
- Transmission: ≥ or ≤ ... %
- Desired limit in %: ≥ for “at least” or ≤ for “at most”. Transmission describes the fraction of light that passes through the filter.
Detector & blocking
- Detector sensitivity: from ... nm to ... nm
- Wavelength range in which your detector is sensitive.
- Blocking range: from ... nm to ... nm
- Wavelength range in which unwanted light should be suppressed.
- Blocking depth: 10−3, 10−4 or 10−5
- Desired maximum residual transmission in the blocking range. A smaller value means stronger suppression.
Geometry & installation
- Angle of incidence: ... degrees (°)
- Angle of the light beam to the surface normal in degrees (°). An angle of 0° means the light strikes the filter perpendicularly.
- Maximum thickness: ... mm
- Maximum permitted filter thickness in mm.
- Dimensions: Ø ... mm or ▭︎ ... × ... in mm
- Round: diameter Ø in mm. Rectangular: length × width in mm.
- Clear aperture (CA): Ø ... mm
- Optically usable area of the filter: desired clear diameter Ø in mm.
Quantity & supporting information
- Required quantity: ... pcs.
- Desired quantity; an initial estimate is also helpful.
- Additional requirements & preferences
- Describe your application and any additional requirements or preferences in your own words.
- Optional attachments
- You can attach drawings, existing specifications or measurement curves to your email as PDF, JPG or PNG files.