Oculus Photonics has teamed up with Santa Barbara Imaging to create some new solutions for ultraviolet microscopy in the longwave UV band (365nm wavelength range). Here is an image of the 2X UV microscope system (5.28mm by 2.97mm field of view) imaging the back of a $20 bill:
The color image on the left shows one of the yellow-colored “20” text on the back of a $20 bill. The image below is the same text imaged at 365nm.
This is a pair of images of an index finger fingertip in the color visible band and at 365nm:
The microscope has applications for industrial inspection and forensics when the material being imaged is semitransparent in the visible band. The UV rays tend to be more heavily absorbed and scattered off surfaces, which throws them into greater contrast.