What is flatness / RWE classification?

Wavefront distortion can degrade image quality by reducing contrast or compromising resolution. In several microscopy applications, reducing wavefront distortion is critical to achieving the microscopy method.

IDEX Health & Science offers an extensive and industry-leading range of Semrock brand catalog filters for a variety of applications with specific Flatness / RWE needs. The Flatness Classifications listed in the table below provide an intuitive approach to selecting products of appropriate flatness for a given application.

In determining suitable flatness need for a given application, the most important parameter is often the diameter of the beam striking the dichroic beamsplitter surface. The table below shows the Semrock optical filters best suited to the application, for maximum diameter values. For more specific information, and for other beam diameter value and microscopy examples, the Technical Note and White Paper on this topic [1, 2] provide additional information on RWE, TWE, and microscopy methods, as well as guidance from a system designer’s perspective.

[1] Technical Note: Choosing Dichroic Beamsplitters with Flatness/RWE Appropriate to the Microscopy Method

[2] White Paper: Maximizing the Performance of Advanced Microscopes by Controlling Wavefront Error Using Optical Filters