On Sunday, 27 October 2019 07:47:50 UTC, wrote:
On Saturday, 26 October 2019 21:29:50 UTC+1, polygonum_on_google wrote:

I think the UV ones have been phased out, largely due to the impact of UV on the dental staff.

They were using blue light 30 years ago. In those days it was
produced by filtering the light from a quartz halogen projector
lamp before sending it down an optical fibre light pipe.

Nowadays I imagine blue LEDs would be the preferred light source.

John

LEDs are, most certainly, the choice. Gets the exact wavelength required and can easily be run from a battery.