Notch Filter


He Rui optics' notch filter, also known as a band-stop filter or negative filter, is a specialized optical component designed to transmit most wavelengths while attenuating light within a specific wavelength range to a very low level. These filters find wide applications in medical, scientific, and industrial fields, such as effectively attenuating excitation light or stray light to improve the signal-to-background ratio, enhancing image quality and measurement precision.

There are two types of neutral density filters: reflective and absorbent. Reflective neutral density filters consist of a metal coating on a glass substrate, which primarily reflects light back to the source. Absorptive neutral density filters use a glass substrate to absorb a certain percentage of light.Reflective filters use the principle of thin-film interference to transmit part of the light while reflecting the rest, which can easily cause stray light and reduce experimental accuracy. Absorptive filters, on the other hand, involve the material itself or the material doped with certain elements absorbing specific wavelengths of light, while having little to no effect on other wavelengths.Neutral density filters are widely used in applications where light control is necessary, such as photography, laser equipment, optical instruments, and more. They help users better control exposure times, aperture sizes, and achieve certain special effects without overexposure due to excessive light

Materialoptical glass
ShapeRound,Square or Special shape
Diameter&Tolerance1-400±0.1mm
Thickness&Tolerance0.1-3±0.05mm
Transmission As per your need
Flatness1λ or better
Surface quality60/40 or better

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Can be customized according to your requirements




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