+1/-1 order phase masks

Easy and cost-effective fabrication of Bragg gratings

Ibsen’s +1/-1 order principle phase masks ensure quality and facilitate production in the telecommunications, sensor, and laser industries. In the production of fiber and waveguide Bragg gratings, the phase mask is illuminated by a laser. Self-interference between the diffracted first orders produces the required pitch in the fiber or waveguide.

Any deviation from the desired grating structure in the Phase mask is transferred directly to the fiber or waveguide. It is therefore imperative that the Phase mask pitch is accurate, uniform, and defect-free. Through scientific principles and constants of nature, our fabrication process ensures absolute pitch accuracy. In addition, geometric principles in our production equipment ensure strict uniformity, eliminating e-beam drawbacks such as stitching errors and field distortion.

Other important features of our line of +1/-1 order Phase masks are:

Key benefits

  • Phase mask pitches for all fiber/waveguide applications, down to 260 nm period and through the 1310 and 1550 nm wavelength ranges

  • Period accuracy and uniformity better than 0.01 nm

  • Highly suppressed residual zero order (typical: 0-2%)

  • Optimized for illumination from 193 nm to 1065 nm

  • Illumination can be CW, pulsed and even femtosecond

  • Inherently free of stitching errors

  • Continuous linear chirp available

  • Multiple period phase masks are possible

  • Tilted gratings are possible

  • Phase shifts are possible

  • Phase mask parameters are individually specified – including unique part number – on each phase mask

Ibsen Photonics telecom gratings

Important applications

  • FBGs for telecommunications

  • FBGs for structural health monitoring

  • FBGs for civil engineering

  • FBGs for shape sensing

  • FBGs for environmental monitoring

  • FBGs for fiber lasers

  • Waveguide gratings

Product overview

Ibsen Phase masks are cost-effectively fabricated one-off with customized parameters as defined by the customer. Request a quote below!

+1/-1 order principle

Using the +1/-1 order principle, the phase mask is optimized to diffract light equally and maximally into the plus first and minus first orders. Self-interference between these two orders creates an interference pattern with half the pitch of the phase mask pitch. As the diagram illustrates, a +1/-1 order phase mask can generate additional unwanted orders. Ibsen phase masks have highly suppressed zero order noise. The main advantage of this +1/-1 order principle (relative to the 0/-1 order principle) is its ease of use with normally incident illumination.

Documentation

Product range and specifications

ParameterSpecification
Grating periods260 nm - 2650 nm
Illumination wavelengths193 nm - 1065 nm
MaterialUV grade fused silica
Period accuracy+/- 0.01 nm
Period uniformity+/- 0.01 nm
Chirp rates0 - 30 nm/cm
Standard grating sizes10 mm x 10 mm
25 mm x 10 mm
50 mm x 10 mm
100 mm x 10 mm
Guaranteed 0. order suppression<3% (lower spec optional)
Typical 0. order suppression0-2 %
0. order uniformity
Grating length 10 mm+/- 0.5 %
Grating length 25 mm+/- 0.75 %
Grating length 50 mm+/- 1.0 %
Grating length 100 mm+/- 1.5 %

Ibsen as your grating manufacturer

At Ibsen Photonics, we recognize that the optical grating is a mission-critical component in your device or instrument – where performance and reliability are non-negotiable.

As an ISO 9001 and 13485 certified manufacturer, we bring decades of expertise in both prototyping and high-volume production of transmission gratings. Our focus is unwavering: to deliver superior, consistent quality.

Our commitment is backed by robust, proven designs, 100% metrology on diffraction efficiency, and comprehensive outgoing inspection. The result? Over hundreds of thousands of gratings deployed in the field – without a single reliability failure or return.

We maintain stable supply chains through long-standing partnerships with qualified sub-suppliers and offer flexible delivery models tailored to OEM needs, including frame orders and Kanban agreements.

Partnering with Ibsen means you can rely on a trusted, experienced grating supplier – so you can stay focused on advancing your core technology.

Advantages working with Ibsen:

  • Specialists in both prototyping and scalable, volume manufacturing

  • Advanced design capabilities and close communication with our customers

  • ISO 9001 and 13485 certified with decades of experience

  • High and consistent quality assurance

  • Stable supply chain with flexible supply options

  • Enabling you to focus on your core business

Which phase mask to use?

For further information or to request a quotation please contact us.

Ask the experts

Do you want to discuss your phase mask project with one of our experts? Please fill out the form, and we will contact you as soon as possible.

Get a price

Want to know the price of any of our phase masks or services?
Just request a quotation and type in your special requirements, if you have any.