"Ultraviolet C light with a wavelength of 222 nanometers"
https://www.hiroshima-u.ac.jp/en/news/60119
"The light, which contains the carrier and a mixture of selected signals in the UV range, stimulates the biological material in the Somatoscope to the point that the specimens give off their own light. (Rife referred to this as luminescence.) This is the key to the ultra-high resolution that has been achieved by Gaston Naessens."
"the illumination source is actually stimulating the specimen to the point it generates its own light. The light itself expands as it moves outward and because the specimen itself is generating the light, the physical restrictions encountered by regular optical microscopes do not apply."
http://whale.to/v/naessens.html
"Rife noted that the different frequencies of light caused certain microorganisms to illuminate (light up) in their own resonant colors."
https://rifedigital.com/the-original-rife-microscope/
"By converting the specimen into a light source, Gaston Naessens has converted the magnification problem from one of resolution to that of light detection!"
https://principia-scientific.com/super-microscopes-and-suppressed-cancer-treatments/
"Royal Rife discovered the unique spectroscopic signature of each cancer virus. Then he used the color wavelength (spectroscopic signature) to make them visible under the virus microscope (Universal Microscope).
The science behind this is resonant frequency in light wavelengths. The individual beam or light ray hits the virus and the virus resonates or vibrates making it visible under the special microscope."
http://www.make100healthy.com/royal-rife-and-bob-beck-can-their-electro-medicine-defeat-cancer-2/