FB700-10 In Stock

The ThorLabs FB700-10 is a soft-coated bandpass filter that effectively transmits a particular wavelength band of light while also rejecting any other radiation that is unwanted at the same time. The FB700-10 is enclosed in a durable black ring that is made of anodized aluminum and has an arrow to indicate the design propagation direction, making handling easier and improving the blocking optical density by limiting scattering.

The FB700-10 is constructed similarly to a thin film Fabry-Perot Interferometer using vacuum deposition techniques. It is made up of two distinct stacks, divided by a spacers layer with an even number of components. These reflecting stacks are made up of alternating layers of high and low refractive index materials, resulting in a reflectance greater than 99.99%. The central wavelength and bandwidth of the filter can be adjusted by changing the thickness of the spacer layer and/or the number of reflecting layers. The FB700-10 is optimized for use at a 0° angle of incidence (AOI) due to its Fabry-Perot design. The transmission band can be shifted in wavelength and may be reduced when used with other AOIs.

The FB700-10 has a narrow spectral range of blocked light on either side of the bandpass region, and an additional blocking component is added to compensate for this. Depending on the filter's requirements, this component can be either all dielectric or metal-dielectric. While this component eliminates any unwanted out-of-band radiation, it also reduces the overall transmission throughput of the FB700-10. This filter is compatible with various filter mounts and wheels, and retaining rings are required to mount the filters into an internally-threaded lens tube since the mounts are not threaded. It is not recommended to remove the filter from the mount, as the filter consists of several layers of glass held together with epoxy and the mounting ring, and these glass layers protect the dielectric coating from the atmosphere. Constant exposure to the air can erode the filter's ability to effectively block out particles over time. This can significantly decrease its transmission efficiency. Also, due to the gradual breakdown of the dielectric coating caused by water vapor, the FB700-10 has a typical lifetime of two years.