Our colleagues in Italy have designed and patented UV lamps
The lamp emits either 100% Narrowband UVB or a mix of Narrowband UVB and Broadband UVA so the lamp is able to increase vitamin D and it will also give you some colour. (The reason you turn brown in the Sun is because the UVA is oxidizing your melanin. Melanin is the pigment that is produced by the melanocytes.) It's the same reason that when you cut an apple in half and expose it to oxygen it turns brown!
It is important though for the skin that UVA is always combined with UVB because UVB is what generates the melanin and translocates (shifts) that melanin to the apex of the nucleus. The melanin migrates to create a sheild over the DNA absorbing the reactive oxygen species generated by the UVA and acting as a free radical sponge.
Here is the link to lamp: https://shop.evolutamente.it/it/home/150-lampada-uv-uv-lamp-elioslamp-mars.html?fbclid=IwAR1lGzaP-JK-v14CkPgX3utrf099c8XWI-Ijh4AC-OHd-sPNY5N77krtWk8
Let us know how you like them.
Your team @ EMR-TEK