LEDs for Deep UV Imaging

As a result of our work with lanthanide imaging, I’ve acquired an interest in excitation sources in the deep UV (DUV; around 280 nm). When we started a few years ago, the only options were arc lamps.  Now there are a number of companies that produce DUV LEDs with decent emission powers. I haven’t yet tried any of these, though I plan to soon; I’m posting this list in case someone else is looking for suppliers.

Thorlabs makes a mounted LED that provides 25 mW at 280 nm.  Other suppliers of component LEDs (i.e. you supply the power source and mounting) are:

5 thoughts on “LEDs for Deep UV Imaging

    • Well, we don’t image in the UV; we excite visible luminescence with the UV excitation and then image that. Most cameras have pretty poor UV sensitivity, but special cameras for UV imaging are available, if you want to do that. Also glass is not transparent to DUV light, so you need to use special (quartz and fluorite) optics.

      • So it would be futile to couple a DUV light (or even a UV light) to the epi port of a upright microscope, right? How could you then use the UV LED light as a source: simply illuminate your sample from the side with an appropriate fiber? How do you create an even distribution of light in this case (not just from one side)?

        • You are correct. Most microscope objectives (even Fluor ones) won’t transmit wavelengths shorter than about 340 nm. Ordinary glass stops transmitting at about 320 nm. In some previous work we used transmitted light illumination for exciting in the deep UV. To do so, we replaced the condenser optics with quartz lenses. We’ve also experimented with LED epi-illumination by making an objective mounted ring illuminator of LEDs; this gives pretty uniform illumination but we haven’t yet tested it carefully. I should do a post on that.

Comments are closed.