Dichroic Beam Turner on output of 250 W Research Lamp Housing
These beam turners turn the output beam from an Oriel® Light Source 90° in any direction without affecting the collimation. Fig.1 shows an example. You can reflect the entire lamp output or only a selected portion of the UV and VIS spectrum. This is useful for applications where the IR is troublesome, particularly with our high wattage quartz tungsten halogen and arc sources. Beam Turners are made up of two components: the mirror and mirror holder. The components are sold separately so you can interchange the mirrors.
We offer two types of beam turning mirrors: full reflectors and dichroics. The full reflectors are coated with an AlMgF2 coating optimized to increase reflectivity in the ultraviolet. They are useful from 200 nm to 30 µm. See Fig. 2 for a reflectance curve. Use them when broadband output is needed.The dichroic mirrors are designed for high reflectance and polarization insensitivity over a limited spectral range in the UV and/or VIS. They pass most of the unwanted IR radiation to an absorbing assembly behind them, but do not remove all of it (see Fig. 2 for a reflectance curve). We have found that enough infrared is removed to make some irradiation studies practical without further filtering. If further filtering is required, use our Liquid Filters for Light Sources to remove infrared intensity.
Our 500 to 1000 W arc and quartz tungsten halogen sources produce high intensity IR radiation, which may crack bandpass filters and damage fiber bundles. Dichroic mirrors protect optical accessories from the damaging IR. Use the beam turner at the condenser output, and the optical accessory at the beam turner output.
Most of the IR is transmitted through the dichroic mirror and absorbed by the mirror housing. A heat sink dissipates the heat.
The mirror holders have male and female-flanged apertures. The male end fits to the output of an Oriel Lamp Housing condenser. Three sizes are available to accommodate the three sizes of condensers. Match the mirror holder to your condenser series size. The female end accepts lens holders, shutters, or other male-flanged components.
The outside of the mirror housing, particularly the fins of the heat sink, become very hot, especially when used with our high wattage sources. Personnel should use caution when working around these sources.